ALBERT

Description: Der Ausbau Erneuerbarer Energien bedarf eines breiten Engagements lokaler Ak­teure. Kommunen mangelt es jedoch häufig an ausreichenden Ressourcen und die Rolle von Beratungs­stellen und Vermittlern wird daher immer wichtiger.

Description: Eine Teilung des deutschen Marktgebietes würde die Marktwerte erneuerbarer Energien beeinflussen. Wind und Photovoltaik (PV) im Süden Deutschlands würden an Wert gewinnen, während Erneuerbare im Norden Erlöse einbüßen würden. Bei einer auch zukünftig stärkeren Konzentration von erneuerbaren Energien im Norden bedeutet dies insgesamt einen höheren Förderbedarf für PV – Wind wäre trotz niedriger Marktwerte in den meisten Regionen wirtschaftlich. Wenn eine regionale Steuerung erreicht werden soll, müsste die auszuzahlende Förderung für neue PV-Anlagen anhand des zonenübergreifenden Referenzmarktwertes berechnet werden. Durchschnittliche Börsenstrompreise würden durch eine Gebotszonenteilung im Süden Deutschlands leicht angehoben und im Norden gesenkt, die Effekte auf Endkundenpreise und damit verbundene Anreize zur Standortwahl von Industrieunternehmen sind allerdings als gering einzuschätzen.

Description: Ethiopia is highly vulnerable to climate change, the impacts of which can be felt across different sectors. In particular forests are threatened by rising temperatures, shifting precipitation patterns and extreme weather events. Human activities like deforestation and land-use change further exacerbate climate impacts, increasing the risk of wildfires and reducing the potential of forests for carbon sequestration. However, forests and trees are of major importance for ecosystems and local communities, providing plant and animal habitat, protection against soil erosion, provision of sufficient water resources, wood for fuel and construction, and various non-timber products. In addition, climate change is increasingly impacting water resources through prolonged and more frequent droughts, leading to water scarcity, crop failures and food insecurity for millions of people in Ethiopia. At the same time, erratic and heavy precipitation events lead to increased instances of flooding and soil erosion, further compromising water availability and quality. In a similar way, soils are impacted by climate change, with temperature increases and shifting precipitation patterns leading to soil degradation and reduced soil fertility, making it harder for smallholder farmers to pursue agriculture as a livelihood. Forests and trees are particularly threatened by climate change. At the same time, they are key in both climate change mitigation and adaptation efforts. Against this background, this policy brief discusses the potential of forests and trees in addressing climate change, specifically looking at natural forest regeneration as a mitigation strategy and at agroforestry as an adaptation strategy, highlighting the unique potential of forests and trees to achieve a dual benefit for climate action. Although these strategies are considered in greater detail, it should be noted that there is no single best mitigation or adaptation strategy, but rather different mutually complementing strategies. Mitigation describes efforts to reduce greenhouse gas emissions as well as measures to enhance greenhouse gas sinks. Forest and tree-based mitigation options can be classified as efforts to maintain the remaining forest cover (reduce deforestation and degradation), and measures to increase forest cover (natural regeneration and reforestation) (Nabuurs et al., 2007). We briefly describe each strategy but focus on natural regeneration later on.

Description: Die Energiewende sorgt für einen Paradigmenwechsel von einem grundlastbasierten zu einem flexiblen Stromsystem. Die zentralen Treiber für den zunehmenden Flexibilitätsbedarf sind die Stromerzeugung durch Wind und Sonne sowie die weiterhin bestehende unflexible Stromnachfrage, die gedeckt werden muss. Die vorliegende Studie analysiert, wie im Zeitverlauf bis zum Jahr 2045 der Flexibilitätsbedarf zunimmt und wie die Betriebsweisen der verschiedenen Technologien sich anpassen können. In der Studie wird auf das Energiesystemmodell REMod zurückgegriffen, mit dem eine Analyse über die intersektorale Flexibilität bis zum Jahr 2045 möglich ist. Für kurzfristige Flexibilität können in dieser Betrachtung zum Beispiel Batterien sowie Stromimporte und -exporte eingesetzt werden. Durch die Sektorenkopplung kann bei der Wärmebereitstellung in Gebäuden ebenfalls ein erheblich angepasstes Lastmanagement erfolgen. Ein höherer Anteil an Flexibilität kann jedoch durch Stromaufnahme in Elektrolyseanlagen und die Nutzung von Power-to-X-Kraftstoffen erfolgen. So können während längerer Dunkelflauten flexible Backup-Gasturbinen eingesetzt werden, um die Versorgungssicherheit zu gewährleisten. Um die notwendige Integration der Flexibilitäts-Technologien in den verschiedenen Märkten (insbesondere Strommarkt) und Sektoren voranzutreiben, müssen technische Voraussetzung, Marktregeln sowie Regulatorik in Bezug auf Bau und Betrieb so angepasst werden, dass die Technologien ihr Flexibilitätspotential bestmöglich ausspielen können.

Description: Mit steigendem Anteil fluktuierender Erneuerbarer Energien im Stromsystem steigt auch der Bedarf an steuerbaren Kapazitäten, die Stromangebot und -nachfrage ausgleichen können, so genannte Flexibilitätstechnologien. In dieser Analyse wird der Nutzen von zehn verschiedenen Technologien, die Flexibilität bereitstellen können, für das deutsche Stromsystem im Jahr 2030 ermittelt. Die Nutzenanalyse macht deutlich, dass die Verschiebung von großen Energiemengen über einen längeren Zeitraum (saisonaler Ausgleich) den höchsten spezifischen Nutzen erreicht. Eine Schlüsseltechnologie für das Jahr 2030 sind daher Langzeitspeicher mit großen Speichervolumen, zum Beispiel in Form von Wasserstoff-Kavernenspeichern. Das Fehlen einer hierfür geeigneten Technologie würde zu hohen Effizienzverlusten führen. Die zweite Schlüsseltechnologie ist die steuerbare Leistung von Power-to-Heat1 in Wärmenetzen der allgemeinen Versorgung, die für den täglichen Ausgleich zwischen Nachfrage und erneuerbarer Erzeugung eingesetzt wird. Hier können allerdings auch andere nachfrageseitige Flexibilitäten eine ähnliche Funktion für das Stromsystem übernehmen. Die Analyse zeigt auch, dass die Erschließung der hier betrachteten Flexibilitätstechnologien, zum Beispiel durch den Abbau von regulatorischen Hemmnissen, bis zum Jahr 2030 für das Stromsystem von hoher Relevanz ist. Auch über die angenommenen Potentialgrenzen hinaus bieten insbesondere nachfrageseitige Flexibilitätstechnologien noch einen positiven Nutzen. Eine technologieoffene, marktbasierte Lösung zur Einbindung dieser Flexibilitäten könnte die unterschiedlichen Charakteristika, Nutzenniveaus sowie sich ändernde Rahmenbedingungen effizient berücksichtigen.

Description: Im Kopernikus-Projekt Ariadne wurden zufällig ausgewählte Bürgerinnen und Bürger aus ganz Deutschland in einem Forschungs- und Lernprozess zur Verkehrs- und Stromwende beteiligt. Dieser Lernprozess eröffnete neue Begegnungs- und Reflexionsräume, in denen Forschende und Bürger:innen über verschiedene Politikoptionen zur Energie- und Verkehrswende diskutieren konnten.

Description: Wohngebäude sind für 11 % der Treibhausgasemissionen in Deutschland direkt verantwortlich und für bis zu 40 %, wenn Stromverbrauch mit einbezogen wird. Um die Klimaziele gemäß dem Bundes-Klimaschutzgesetz zu erreichen, ist ein höheres Ambitionsniveau der klimapolitischen Maßnahmen in diesem Sektor erforderlich. Dieser Bericht analysiert die Governance der Evaluierungsprozesse von Maßnahmen im deutschen Gebäudesektor. Wir analysieren die Rollen der beteiligten Akteure, das institutionelle Gefüge sowie die angewandten Metriken und Methoden der Evaluierungen.

Description: Residential buildings directly contribute 11% to local greenhouse gas emissions and up to 40% of total emissions when accounting for energy use for electricity generation. In order to achieve the climate targets in line with the Federal Climate Protection Act, increased ambition level of climate policy instruments is required in this sector. In this research, we are interested in the governance of this sector and the role of evaluation: the government-mandated processes used to evaluate policy in terms of the actors, organisations and ministries involved in executing and coordinating these processes; and the metrics and methods as well as the scope and granularity of evaluations.

Description: Die Entscheidung für den Austausch oder Ersatz eines Heizsystems ist eine, die für mehr als ein Jahrzehnt getroffen wird. Oftmals berücksichtigen Verbraucherinnen und Verbraucher dabei vor allem die einmal anfallende Einbau-Investition. Die Kosten über den gesamten Lebenszyklus sind deutlich schwerer zu ermitteln und unsicher, daher werden sie häufig zu wenig in die finanzielle Überlegung mit einbezogen. In einer neuen Analyse haben Ariadne-Forschende berechnet, wie hoch unterm Strich die Kosten für verschiedene Heiztechniken in bestehenden Wohngebäuden über einen Zeitraum von 20 Jahren angesichts zukünftiger Energieträgerpreise sowie der zu erwartenden CO2-Preisentwicklung sind.

Description: There has long been a debate about climate-damaging subsidies in the German transport sector, and the financial restrictions resulting from the Federal Constitutional Court’s budget judgement at the end of 2023 have intensified the debate. This dossier is the first to convert the level of subsidies in the transport sector into negative CO2 prices to present a scientific categorisation of their significance for climate policy. The concept of implicit negative CO2 prices shows the extent to which subsidies implicitly reward citizens for emitting a tonne of CO2, rather than paying for the emissions.

Description: Subventionen im Verkehr, wie das Diesel- oder Dienstwagenprivileg, bedeuten negative CO2-Preise in Höhe von minus 70 bis zu minus 690 Euro pro Tonne CO2 und schwächen die Wirkungsweise der CO2-Bepreisung als wichtiges Instrument der Klimapolitik. Das zeigen Forschende des vom Bundesministerium für Bildung und Forschung (BMBF) geförderten Kopernikus-Projekts Ariadne in einer neuen Studie. Die Ariadne-Berechnungen unterstreichen, dass Deutschlands derzeitiges Steuer- und Abgabesystem im Verkehrssektor noch stark auf die Nutzung fossiler Energieträger ausgerichtet ist und so die Erreichung der deutschen Klimaziele erschwert.

Description: As part of the Earth4All project, collaborators have submitted this paper to delve further into the steps to be taken to widely transform our conventional agricultural system to provide food security and improve ecological resilience in a rapidly changing global climate. This article analyses the potential positive effects on soil ecology and crop yield of a global-scale transition to regenerative agriculture, while also considering social spreading dynamics that determine the adoption of such practices by farmers. The authors argue that the transition to a global regenerative agricultural system cannot be achieved without considering the deeper societal processes driving the effective dissemination and adoption of the change. Furthermore, the surrounding factors and conditions such as farmers’ political and institutional embeddedness, public opinion, the economic situation and the climate conditions they face within their region or community, as potential barriers hindering the transition, have to be taken into account. Therefore, it is not only the farmers’ responsibility to drive the change but also the politicians, institutions, companies and individual actors’ one which, all together, will support such transition processes.

Description: Um die ambitionierten Klimaschutzziele zu erreichen, braucht Deutschland effektive Instrumente und Maßnahmen auf nationaler, bundesstaatlicher und kommunaler Ebene. Der Erfolg dieser Politik wird maßgeblich davon abhängen, ob es gelingt, eine breite gesellschaftliche Akzeptanz und Unterstützung für diese Maßnahmen auf den entsprechenden Ebenen zu erreichen. Die Haltung der Bevölkerung wird jedoch in der Regel auf nationaler Ebene über Umfragen gemessen, die geographische Unterschiede dabei auf den subnationalen Ebenen außer Acht lassen. Im Rahmen dieser Analyse schätzen wir die durchschnittliche Bevölkerungszustimmung zu 26 Klimaschutzmaßnahmen in den Sektoren Wärme, Transport und Energie auf Bundesland-, Landkreis- und kommunaler Ebene zwischen 2017 und 2021 mittels eines mehrstufigen Regressions- und Poststratifizierungsmodells. Die Schätzungen basieren auf zwei bundesweit repräsentativen Panel-Umfragen, dem Sozialen Nachhaltigkeitsbarometer und dem Ariadne Wärme-& Wohnen-Panel. Durch die Analyse werden erhebliche regionale Unterschiede in der Zustimmung von Klimaschutzmaßnahmen in der deutschen Bevölkerung sichtbar. Die Befürwortung einzelner Klimaschutzmaßnahmen variiert teilweise um bis zu 60 Prozentpunkte zwischen den untersuchten geographischen Einheiten. In der Gesamtbetrachtung der räumlichen Disparitäten zeichnen sich bedeutsame Unterschiede zwischen Stadt- und Landbevölkerung sowie West- und Ostdeutschland ab. Im zeitlichen Verlauf haben sich dabei die Einstellungen gegenüber einzelnen Maßnahmen, wie beispielsweise dem Ausbau von Wind- und Solarkraftanlagen, angenähert, während die öffentliche Meinung zu anderen energiepolitischen Instrumenten, wie dem Kohleausstieg, im Laufe der Jahre polarisieren. Mittels einer zusätzlich durchgeführten räumlichen Panelanalyse können wir zudem zeigen, dass sich die Veränderungen von bestimmten Kontextfaktoren auf die Zustimmung von Klimaschutzmaßnahmen auf kommunaler Ebene auswirken. So finden wir einen positiven Zusammenhang zwischen der Befürwortung des Ausbaus von Wind- und Solarkraftanlagen und dem tatsächlichen Zubau an Solar- und Windkapazitäten in diesen Regionen. Ferner wird die Haltung gegenüber klimapolitischen Maßnahmen stark von räumlichen Diffusionseffekten, d.h. der Ausbreitung von Einstellungen im sozialen Umfeld, bestimmt, wie der Einfluss von Meinungsänderungen in einer Region auf deren Nachbarregionen veranschaulicht. Die in diesem Bericht und auf dem interaktiven Online-Dashboard zur Verfügung gestellten Schätzungen der Zustimmung zu Klimaschutzmaßnahmen, stellen eine wichtige Informationsgrundlage für politische Entscheidungsträger:innen dar, um den gesellschaftlichen Herausforderungen bei der Umsetzung von Klimaschutzmaßnahmen effektiv zu begegnen. Alle generierten Daten sind im Online-Dashboard „Lokale Klimaschutzeinstellungen in Deutschland“ unter https://hertie-school-ariadne.shinyapps.io/LocalAttitudesDashboard/ einsehbar.

Description: Wie schon 2021 hat der Gebäudesektor auch im vergangenen Jahr die erlaubten Emissionen gemäß Bundes-Klimaschutzgesetz überschritten. Die Fernwärme kann einen Beitrag leisten, um die Trendwende hin zur angestrebten Klimaneutralität zu schaffen. Klar ist aber auch, dass die Wärmenetze der Zukunft deutlich flexibler und effizienter werden müssen, etwa um aus erneuerbaren Quellen oder Abwärme von Rechenzentren gewonnene Wärme nutzen zu können. Angesichts der hohen Lebensdauer der Wärmenetze von etwa 50 bis 60 Jahren ist ein Umbau dieser Netze auf die Erfordernisse der Wärmewende besonders kritisch. Allerding müssen für eine erfolgreiche Anpassung verschiedene Ebenen ineinandergreifen: Die kommunale Wärmewende, die Transformation der Netze sowie die Digitalisierung der Verbrauchsmessungen. Ergebnis der Ariadne-Analyse ist, dass für die erforderlichen Umrüstungen der Netze ein massives Finanzierungsproblem besteht. So bleiben Fernwärmenetzbetreiber auf etwa 90% der Investitionskosten sitzen. Durch eine Nahverdichtung der Fernwärmeanschlüsse könnten die Kosten verringert werden. Weiterhin bietet die Nachrüstung der Wärmezähler für die Fernauslesbarkeit bis Ende 2026 die Möglichkeit, Maßnahmen zu kombinieren, etwa den Austausch der Hausstation und den hydraulischen Abgleich. Eine koordinierte Einbeziehung der handelnden Akteure könnte daher zur Trendwende im Wärmesektor beitragen.

Description: Die Dekarbonisierung des Verkehrs- und Stromsystems ist ein weitreichender Transformationsprozess, der erhebliche Veränderungen für die Menschen mit sich bringt. Er kann nur als gesamtgesellschaftliche Aufgabe gelingen, die aus Betroffenen Beteiligte macht und Interessen sowie Vorstellungen von Bürgerinnen und Bürgern berücksichtigt. Wirksame Beteiligung im Forschungs- und Politikprozess sind bei der Verkehrs- und Stromwende deshalb unabdingbar. Unterschiedliche Formate, wie Befragungen und Deliberation erlauben es, die Einstellungen aus einem Querschnitt der Gesellschaft zu Politikoptionen zu untersuchen und Betroffene somit an der Entwicklung dieser partizipieren zu lassen. In dieser Analyse untersuchen wir in zwei parallel durchgeführten Befragungen im Rahmen der Ariadne Bürgerdeliberation und einer repräsentativen Panelbefragung die Haltung der Bürger:innen gegenüber verschiedenen Politikoptionen in den Bereichen Verkehr und Strom. Das Ziel war hierbei durch die vergleichende Betrachtung besser zu verstehen, welche Optionen gesellschaftlich mitgetragen werden (und welche nicht) und aus welchen Gründen. Die Verbindung beider Zugänge bietet eine umfassende Perspektive auf die gesellschaftliche Trägerschaft der Energie- und Verkehrswende. Die Bürgerinnen und Bürger sprachen sich in beiden Bereichen – Strom und Verkehr – für möglichst gerechte und effektive politische Optionen aus. Die Mehrheit der Befragten ist bereit, Veränderungen mitzutragen, wenn gewährleistet wird, dass alle Menschen und vulnerable Gruppen Zugang zu bezahlbarer Mobilität und Energieversorgung haben. Dies spiegelt sich in der Wahrnehmung von Stärken der verschiedenen Optionen und dem Wunsch, das Beste aus den Welten und Pfaden zu kombinieren. Für die Energie- und Verkehrswende insgesamt zeigen die Bürger:innensichten die Wichtigkeit einer Politik auf, die sich sowohl an sozialen als auch ökologischen Auswirkungen orientiert. Der klimafreundliche Umbau des Energiesystems wird von einer breiten gesellschaftlichen Mehrheit in Deutschland getragen und die Menschen sind bereit, sich bei der Umsetzung aktiv zu engagieren. Bei der Frage der Art der Gestaltung wird von den 2 Bürger:innen mehrheitlich eine dezentrale Energieversorgungsstruktur bevorzugt. Damit sind jedoch sowohl Hoffnungen als auch Sorgen verbunden. In der Verkehrswende ist den Menschen eine faire Teilhabe an Mobilität wichtig, dass also die verschiedenen Mobilitätsbedürfnisse diverser gesellschaftlicher Gruppen berücksichtigt werden. Neben der sozialen Gerechtigkeit spielt in der Verkehrswende auch die Klimawirkung – also die Effektivität von Maßnahmen – eine zentrale Rolle für die gesellschaftliche Trägerschaft. Trotz verbleibendem Diskussionsbedarf der beteiligten Bürger:innen zu konkreten Umsetzungsfragen zeigen die Ergebnisse die Bereitschaft sich mit den Auswirkungen politischer Optionen auseinanderzusetzen und dadurch Wandel nicht primär als Bedrohung und Sorge, sondern als Chance auf ein inklusiveres und attraktiveres Zusammenleben zu sehen. Eine Voraussetzung für einen wissenschaftlich informierten Lernprozess ist, das Wissen zu Politikoptionen und deren Auswirkungen für die breite Gesellschaft zugänglich und erfahrbar zu machen. Sowohl wissenschaftlich fundierte Informationsangebote als auch verständigungsorientierte Diskussionen sind effektive Formate, um dies zu ermöglichen. Letztlich lebt auch dieser Lernprozess von der Bereitschaft eigene Annahmen zu hinterfragen und sich für neue bzw. andere Argumente zu öffnen, die einem bisher als wenig relevant oder kaum nachvollziehbar erschienen. Zudem unterstreicht diese Analyse, dass in wissenschaftlich gut informierten Prozessen Bürger:innensichten eine wertvolle Ressource und Chance für eine besser gesellschaftlich abgestimmte und damit tragfähigere Klimapolitik darstellen. Aus Bürger:innensicht sollten diverse Wertvorstellungen, Bedürfnisse und Interessen bei der Umsetzung der Transformationen Eingang finden. Deswegen braucht es nach Meinung der Autorinnen und Autoren dieser Analyse einen Weg, wie die Politik über diese informiert wird – eine vielversprechende Möglichkeit hierfür ist die Befähigung von Bürger:innen zur politischen Mitbestimmung durch ein möglichst heterogenes Spektrum an Beteiligungsformen. Aus dieser Sicht stellt der Einbezug von Bürger:innensichten eine Chance für eine tragfähigere, an den Bedürfnissen der Bürger:innen orientierte

Description: Eine kohärente Klimaaußenpolitik (KAP) Deutschlands ist essentiell für das Gelingen sowohl der nationalen und europäischen Energiewende als auch für die effektive Unterstützung ambitionierter Klimapolitik außerhalb der Europäischen Union. Ziel dieses Ariadne- Hintergrundpapiers ist es, einen Diskussionsbeitrag zur Strukturierung der Debatte um die Eckpunkte und Optionen zur Ausarbeitung und Weiterentwicklung der deutschen KAP-Strategie zu leisten. Dazu werden vier Kategorien relevanter Ziele unterschieden. Diese reichen von klassischen klimapolitischen Zielen über industriepolitische sowie sicherheits- und handelspolitische Ziele hin zu breiteren außenpolitischen Zielen. Für jedes Ziel müssen entsprechende Mittel identifiziert werden, mit denen es erreicht werden kann, und Barrieren, die ihm im Weg stehen und entsprechend bedacht werden müssen. Für die Charakterisierung und Analyse verschiedener Mittel werden fünf Kategorien vorgeschlagen. Eine zentrale, aber in der Bewertung konzeptionell und empirisch herausfordernde Kategorie ist dabei das Transformationspotenzial einer Maßnahme. Im Fall von Zielkonflikten und begrenzten Ressourcen müssen Ziele priorisiert werden. Wir skizzieren dafür einen analytischen Rahmen und diskutieren illustrativ mögliche Optionen zur strategischen Gesamtausrichtung. Diese umfassen zum einen KAP-Gesamtstrategien von Staaten gegenüber allen anderen Ländern, und zum anderen Strategien für spezifische Staaten (z.B. die deutsche Strategie für den Umgang mit Indien oder Südafrika). Dabei können Strategien in einem Kontinuum von maximaler Priorisierung von Klimazielen (Klimapolitik First) bis hin zur nachrangigen Behandlung (Klimapolitik als Mittel zum Zweck) verortet und entsprechend ausgestaltet werden. Neben den Inhalten der Strategie werden Fragen der Organisation und Koordination in der Entwicklung und Implementierung der KAP-Strategie in den Blick genommen und die nächsten Schritte diskutiert. Eine erfolgreiche KAP-Strategie sollte dabei von Beginn an zwischen zentralen Stakeholdern im In- und Ausland in jeweils geeigneten Formaten erarbeitet, implementiert und im Sinne eines Lernprozesses fortlaufend angepasst werden. Eine KAP sollte sich in die breitere Außen- und Sicherheitspolitik Deutschlands einfügen, da relevante Politikfelder auf verschiedenen Ebenen eng miteinander verbunden sind. Bei der Erarbeitung der neuen KAP-Strategie der Bundesregierung sollte dazu insbesondere auf Kohärenz zur deutschen Sicherheits- und der Chinastrategie geachtet werden. 2 Grundlage der Strategieentwicklung ist die Klärung möglicher Ziele und Mittel der deutschen KAP und ihrer Wechselwirkungen miteinander. Eine KAP-Strategie muss durch Analysen zu Umsetzbarkeit und Kosten, politischen Wi-derständen und Zielkonflikten informiert sein und die normativen Vorgaben der deut-schen Außenpolitik berücksichtigen.

Description: Die Energiemärkte sind seit Beginn des Angriffskriegs auf die Ukraine sehr angespannt. Gleichzeitig besteht mit Blick auf die notwendige Erreichung von Klimaneutralität bereits ein großer Transformationsbedarf mit potenziell großen ökonomischen Wirkungen. Um abzuschätzen, welche zusätzlichen ökonomischen Folgen der mittel- bis langfristige Wegfall Russlands als Lieferant fossiler Energieträger bei gleichzeitigem Festhalten an den Klimazielen hat, wird das Szenario Energiesouveränität mit dem Szenario Technologiemix verglichen.

Description: In Kapitel 5 unseres englischsprachigen Reports (Zwar et al. 2023) gehen wir vor dem Hintergrund unserer vergleichenden empirischen Analyse von Klimainstitutionen gezielt auf die anstehende Klimaschutznovelle in Deutschland ein (die Reform des Bundes- Klimaschutzgesetzes (KSG)). Dieses Dokument ist die Übersetzung des für die deutsche Debatte besonders relevanten Kapitels.

Description: Countries around the world have set increasingly ambitious targets to reduce greenhouse gas emissions and mitigate climate change. To deliver on these targets, policymakers have (i) implemented new policy instruments, (ii) increased the stringency of existing policy instruments, and (iii) created ‘climate institutions’. A substantial body of literature is devoted to the first two phenomena. Yet we know little about climate institutions, including the different types of institutions countries create and how they affect the development and stringency of climate policy (Dubash 2021; Dubash et al. 2021). This report therefore seeks to answer three research questions. First, what are climate institutions and how can we characterise them across countries? Second, what effects do climate institutions have on climate policymaking? Third, based on these findings, what lessons can we draw about the landscape of German climate institutions and what options exist for institutional reform? To address these questions, we propose a definition of climate institutions and develop a conceptual framework for analysing and comparing their effects on climate policymaking in four countries: Germany, the United Kingdom, Sweden, and Australia. We then draw on this framework and our comparative analysis to identify potentially promising reforms for German climate governance, especially in light of the proposed changes to the German climate law (the Bundes-Klimaschutzgesetz, or KSG).

Description: In diesem Papier untersuchen wir erstmalig die zukünftige direkte Kostenbelastung, die Haushalten durch unterschiedlich ansteigende Preise auf CO2-Emissionen in den Bereichen Wärme und Verkehr bis zum Jahr 2050 in Deutschland entstehen könnte. Wir stellen dazu einen methodischen Ansatz vor, in dem wir ein Energiesystemmodell mit Haushaltsdaten verknüpfen und mögliche Technologieanpassungen, wie ein Heizungswechsel oder Umstieg auf ein Elektroauto, der Haushalte unter Verwendung von Machine Learning-Methoden berücksichtigen. Um die Verbreitung verschiedener Heizenergieträger und Kraftstofftypen für Fahrzeuge sowie entsprechende Technologiewechsel der Haushalte für die Zukunft vorhersagen zu können, treffen wir einige vereinfachende Annahmen, wie uneingeschränkte Kapitalverfügbarkeit und perfekte Voraussicht der CO2-Preisentwicklung der Haushalte. Unter diesen Annahmen zeigen unsere Analysen, • dass sowohl niedrige als auch hohe CO2-Preispfade zunächst größtenteils regressiv wirken, also einkommensschwache Haushalte anteilig an ihrem Einkommen bemessen stärker belasten als einkommensstarke Haushalte. Durch unsere Vorhersagen ist jedoch eine schnelle Technologieanpassung in den einkommensschwächsten Haushalten zu beobachten, sodass die regressive Wirkung im Zeitverlauf abnimmt. • Während bei hohen CO2-Preisen im Jahr 2050 Haushalte im Mittel kaum noch CO2 emittieren, gibt es unter einem niedrigen CO2-Preispfad im Jahr 2050 noch einige, insbesondere einkommensstarke, Haushalte, die noch nicht emissionsfrei heizen und/oder Auto fahren. • Die vollständige Rückverteilung der Einnahmen aus dem CO2-Preis in Form einer Pro-Kopf-Pauschale kann sowohl unter dem niedrigen als auch unter dem hohen Preispfad bereits kurzfristig die regressive Verteilungswirkung in eine progressive Verteilungswirkung umkehren. Unsere Ergebnisse zeichnen gerade für einkommensschwache Haushalte ein recht optimistisches Bild, was zum Teil durch die einschränkenden Modellannahmen erklärt werden kann. Durch diese Annahmen wird insgesamt deutlich, dass • eine klare Kommunikation der Politik über die zukünftige CO2-Preis-Entwicklung notwendig ist, um Haushalten Sicherheiten für effiziente Investitionsentscheidungen zu bieten. • Darüber hinaus dürften stärkere, gezielte Unterstützungen für einkommensschwache Haushalte zur Überwindung von Liquiditätsbeschränkungen notwendig werden, um eine Transformation hin zu emissionsarmen Technologien sozial gerecht zu ermöglichen.

Description: Der Ausbau der Erneuerbaren Energien (EE) ist eines der Kernelemente auf dem Weg zur Klimaneutralität. Mit dem Osterpaket der derzeitigen Bundesregierung wurde eine Reihe von Gesetzen erlassen, die den Ausbau voranbringen sollen, indem neben deutlich höheren Ausschreibungen für Windenergie und Freiflächen- Photovoltaik (PV) beziehungsweise wirtschaftlichen Anreizen für Dachflächen-PV auch Genehmigungsverfahren beschleunigt und Flächen bereitgestellt werden. Zusätzlich zu offenen Fragen der technisch- ökonomischen Potenziale kommen Fragen der Akzeptanz auf Seiten der Bürgerinnen und Bürger: Was sind sie bereit mitzutragen und welche Änderungen im gesetzlichen Rahmen braucht es, um weitere gesellschaftliche Potenziale zu heben? Auch die Bundesregierung betont die Bedeutung von Akzeptanz und Teilhabe der Menschen beim Ausbau der Erneuerbaren Energien und greift Ansätze in ihrer Photovoltaik- sowie Wind-an- Land-Strategie auf. Das vorliegende Ariadne-Kurzdossier verbindet verschiedene Perspektiven, die für den Ausbau der Erneuerbaren Energien eine erhebliche Rolle spielen: Flächenpotenziale und Gestaltungsmöglichkeiten der räumlichen Steuerung des Zubaus und Rückwirkungen auf das Übertragungsnetz sowie Fragen der gesellschaftlichen Akzeptanz. Es soll bewertet werden, inwieweit die bundesweiten Ausbauziele des Erneuerbaren-Energie-Gesetzes (EEG) 2023 so umsetzbar sind, dass sie aus Bürgersicht tragfähig sind. Bürgersicht bezieht sich hierbei sowohl auf die Ergebnisse des Deliberationsprozesses mit Bürgerinnen und Bürgern im Rahmen des Projekts Ariadne (Treichel et al., 2022) als auch auf die Resultate von bundesweiten Befragungsstudien des Sozialen Nachhaltigkeitsbarometers der Energie- und Verkehrswende (SNB, Wolf et al., 2022; Wolf et al., 2021). Dabei gehen wir technologiespezifisch in der Bewertung vor und stellen dar, wie diese Bundesziele regional umgesetzt werden können, und was Bürger:innen in Deutschland über die Maßnahmen zur Erreichung der Ausbauziele denken. Dazu werden die Erkenntnisse aus den Dialogformaten mit Bürger:innen beschrieben sowie die sozio-politische und lokale Akzeptanz von Erneuerbare-Energien- Technologien auf Basis des Sozialen Nachhaltigkeitsbarometers (SNB) untersucht. Anschließend werden die einzelnen Technologien, ihre Potenziale in der Fläche sowie rechtliche Fragen in den Blick genommen. Abschließend wird ein Ariadne-Bürger-Szenario vorgestellt, welches sowohl die neuen EE-Ausbauziele, die Flächenpotenziale der Bundesländer als auch Akzeptanzfragen der Ariadne- Bürgerdeliberation mit aufnimmt.

Description: Global warming can still be limited to 1.5°C by 2100 with low overshoot while ensuring that the poor are not hit hardest by climate policies and climate impacts. This is achieved by immediately introducing broad carbon pricing together with re-distributive policies using carbon pricing revenues and further measures to reduce energy consumption, accelerate technological transitions, and transform the land sector. The results from multiple integrated assessment models show that a combination of producer and consumer-oriented measures can work together to rapidly reduce emissions. They also show that re-distributive policies buffer the impact on poor households while allowing them to reap the benefit of avoided climate impacts in the longer term. This demonstrates that a global net zero transition done right not only safeguards the climate but also protects against worsening global inequality. The comprehensive results on 1.5°C pathways in line with the Paris Agreement are synthesised in this report of the European research project NAVIGATE. The new report published at COP28 provides a blueprint for achieving a rapid, fair and efficient transformation to net zero emissions.

Description: Workshop: goal and set-up This document presents the main takeaways and insights from a workshop organised by the Ariadne Project in Brussels on 6 December 2023. Following up on the workshop we conducted last year on the evolution of EU-ETS prices through 2030 and beyond, in this year’s event we wanted to take a closer look at the functioning of the Market Stability Reserve (MSR) - also with a view on its upcoming review in 2026. The focus of the modelbased discussion was the years until 2030, but we also considered effects post 2030 in the discussion if they impacted MSR behaviour in this decade. The workshop convened experts from six organisations that operate carbon market models – academic institutions as well as carbon market analysts

Description: Bei der Energiewende auf dem Weg zur Emissionsneutralität gilt es vor allem, CO2-Emissionen so weit wie möglich zu vermeiden – durch eine zügige Umstellung auf Erneuerbare Energien, innovative klimaneutrale Produktionsverfahren etc. Für eine Netto-Null in der Emissionsbilanz reicht das allein jedoch nicht aus, denn in manchen Bereichen lassen sich Emissionen nicht oder nur sehr schwer vermeiden, zum Beispiel bei bestimmten Industrieprozessen oder in der Landwirtschaft. In dieser Analyse werden in Erweiterung des Ariadne-Szenarienreports (Luderer et al., 2021) die vielschichtigen Wechselbeziehungen zwischen Vermeidungsoptionen und CO2-Entnahmepotenzialen beleuchtet und Handlungsspielräume abgesteckt. Diese Analyse gibt Orientierungspunkte, unter welchen Bedingungen lokal in Deutschland Treibhausgasneutralität erreicht werden könnte. Es zeigt sich, dass nur die Ausnutzung aller verfügbaren Optionen, sowohl bei der Vermeidung von Restemissionen als auch bei der Entnahme von CO2 aus der Atmosphäre, Spielräume eröffnet, die gegen das hohe Risiko, dass nicht alle ambitionierten Annahmen in den Szenarien auch eintreffen werden, absichert.

Description: Zusammenfassung 1. Einleitung 2. Nach Energiewende verbleibende Restemissionen bestimmen den Bedarf an CO2-Entnahme in Deutschland in 2045 3. Angebot an CO2-Entnahme in Deutschland bis 2045 4. Diskussion der Ergebnisse Anhang Literaturangaben

Description: Die nationale und europäische CO2- Bepreisung weist ein wachsendes Einnahmenpotenzial auf (12,5 Milliarden EUR in 2021, insgesamt 178-227 Milliarden EUR bis zum Jahr 2030). Die Mittel werden dem Klima- und Transformationsfonds zugeführt und sind zweckgebunden für Maßnahmen mit energie- und klimapolitischem Bezug. ▶ Diese Einnahmen können dazu beitragen, die Kosten der Klimapolitik für einkommensschwache Haushalte abzufedern, öffentliche und private Klimaschutzinvestitionen zu erhöhen, Wettbewerbsnachteile für energieintensive Unternehmen auszugleichen und die gesellschaftliche Akzeptanz der CO 2-Bepreisung tendenziell zu stärken. ▶ Es werden folgende fünf Optionen betrachtet: Auszahlung eines Klimageldes, Senkung der Stromsteuer, Senkung von Einkommensteuern, gezielte Kompensation von Härtefällen sowie Förderprogramme. Die Optionen werden anhand ihrer volkswirtschaftlichen Effekte (Arbeits- und Investitionsanreize), Emissionswirkung, Verteilungswirkung, Verwaltungsaufwand, Effizienz und gesellschaftlichen Akzeptanz bewertet. ▶ Maßnahmen zur Entlastung von Bürgerinnen und Bürgern sind verteilungspolitisch vorteilhaft, da sie Haushalte mit geringem Einkommen relativ stärker entlasten. Zudem können sie leicht hochskaliert werden. Dadurch könnten politische Aushandlungsprozesse rund um Be- und Entlastungen befriedet und die Akzeptanz der CO2-Bepreisung in der Bevölkerung erhöht werden. ▶ Die Verwendung der Einnahmen für Förderprogramme und öffentliche Investitionen kann zu zusätzlichen Emissionsminderungen führen. Damit können Klimaziele mit einem geringeren CO2-Preisniveau erreicht werden. Gleichzeitig reizen hohe CO2- Preise jedoch auch private Investitionen an, sodass die Notwendigkeit staatlicher Förderprogramme sinkt (und höhere Rückerstattungen zum Ausgleich der Belastung durch den CO 2-Preis erforderlich werden). Die Finanzierung von Förderprogrammen sollte daher grundsätzlich in dem Rahmen erfolgen, wie sie notwendig und sinnvoll ist, und sich nicht nach dem Umfang der Einnahmen aus der CO 2-Bepreisung richten. Andernfalls erhöht sich das Risiko einer Unteroder Überfinanzierung von öffentlichen Ausgaben und Förderprogrammen. ▶ Die Bevölkerung ist bislang skeptisch gegenüber der CO2-Bepreisung, insbesondere bezüglich der wahrgenommenen Lenkungs- und Verteilungswirkung. Die CO2-Bepreisung wird mitunter als Finanzierungsinstrument für Staatseinnahmen gesehen. Förderprogrammen wird dagegen tendenziell eine höhere EfZUSAMMENFASSUNG 1fektivität zur Senkung von Emissionen unterstellt. Die Akzeptanz der CO 2-Bepreisung wie auch der Mittelverwendung hängt jedoch ebenso maßgeblich vom Informationsstand, Diskussionsprozessen und persönlichen Erfahrungen ab. Daraus folgt, dass die Transparenz im Hinblick auf die Verwendung der Einnahmen aus der CO 2-Bepreisung erhöht werden sollte. Unter anderem können Informationskampagnen helfen, ein besseres Verständnis für Wirkung und Nutzen von CO 2-Preisen und Entlastungsmaßnahmen zu vermitteln

Description: 15.000 Haushalte und mehr als 100 Fragen rund um Wärme und Wohnen in Deutschland: Im Herbst 2022 fand die zweite Erhebung des Ariadne Wärme- & Wohnen-Panels statt, das in bislang einzigartiger Weise Informationen zum Gebäudebestand und dem Endenergiebedarf mit detaillierten Angaben zu den sozioökonomischen Charakteristika der Haushalte verknüpft. Der Schwerpunkt der zweiten Panelerhebung lag auf den Auswirkungen der durch den Angriff Russlands auf die Ukraine verursachten Energiekrise auf die privaten Haushalte. Gefragt danach, wie stark die Teilnehmenden von den steigenden Energiepreisen betroffen sind und welche Maßnahmen sie dagegen ergreifen gaben so zum Beispiel lediglich 28 % der Teilnehmenden an, ihren Heizenergieverbrauch im Winter 2022/2023 stark oder sehr stark reduzieren zu wollen. Ein besonders bemerkenswertes Ergebnis ist in diesem Zusammenhang, dass nur etwa 21 % der Antwortenden angaben, die eigens für diesen Zweck entwickelte Informationskampagne der Bundesregierung mit dem Titel „80 Millionen gemeinsam für den Energiewechsel“ wahrgenommen zu haben. Eine überwältigende Mehrheit von etwa 88 % der Befragten hatte dagegen von der für Herbst 2022 geplanten, letztlich aber nie eingeführten Gasumlage gehört. Für die aktuelle Debatte um das faktische Verbot des Einbaus neuer fossil befeuerter Heizkessel höchst relevant ist das Ergebnis, dass ein Einbauverbot für Gaskessel lediglich von rund 28 % der Befragten begrüßt würde. Weiterhin interessant ist, dass 70 % der Eigentümer aus der Stichprobe die steigenden Preise im Bauhauptgewerbe als größten Hinderungsgrund für energetische Modernisierungen ansehen. Dahinter folgt als zweitwichtigstes Hindernis für die Umsetzung der Wärmewende in den eigenen vier Wänden die Unsicherheit über die Preisentwicklung verschiedener Energieträger.

Description: In the 10 Must Knows from Biodiversity Science 45 scientists present facts about biodiversity in a well-founded and generally intelligible way. They analyse the complex systems of the earth by highlighting ten key areas, each of which, in turn, is inextricably linked to all the others. And they show ways to stop the continued loss of species diversity and ecosystems, and to promote biodiversity. The underlying aim is to provide policy-makers and society with scientifically validated assessments of the latest knowledge to facilitate improved policy decisions and action at local, regional, national and global levels, in order to conserve the diversity of life – biodiversity. These are the 10MustKnows 2022: 1. Achieving climate and biodiversity protection together 2. Strengthening planetary health 3. Considering hidden biodiversity 4. Promoting biocultural habitats 5. Using forests sustainably 6. Transforming agriculture 7. Protecting land and resources 8. Expanding transnational infrastructure and education for sustainability 9. Ensuring access and open use of research data 10. Setting biodiversity-friendly incentives

Description: Dieses Papier beschreibt Empfehlungen zur Weiterentwicklung des nationalen Brennstoff-Emissionshandelsgesetzes (BEHG) – und wie ein reibungsfreier Übergang zur europäischen Ebene gestaltet werden kann. Bei der Einführung und Ausgestaltung eines EU-Emissionshandelssystem für Gebäude und Straßenverkehr (EU ETS-II) bestehen derzeit noch diverse Unsicherheiten. Unabhängig von den Entscheidungen auf europäischer Ebene identifizieren wir jedoch vier No-Regret Maßnahmen zur Weiterentwicklung des BEHG, die in allen Fällen förderlich sind: Zeitliches Vorziehen und Anhebung des Preiskorridors plus Versteigerung: Die Einführung eines Preiskorridors und die Versteigerung von Zertifikaten sollte auf das Jahr 2023 vorgezogen werden. Zudem sollte der Preiskorridor angehoben und verbreitert werden, um den neuen nationalen Klimazielen Rechnung zu tragen. BEHG Emissionsmengen analog zu Sektorzielen: Die EU-Kommission hat im Fit-for-55 Paket eine Erhöhung des deutschen ESR-Ziels auf 50% vorgeschlagen, was auch ungefähr den nationalen Zielen im Rahmen des Klimaschutzgesetzes (KSG) von 2021 entspricht. Um zu einem früheren Zeitpunkt Verbindlichkeit zu schaffen, sollten daher die BEHG-Emissionsmengen aus den KSG Sektorzielen abgeleitet werden. Direkte Pro-Kopf-Rückerstattung: Für den zu erwartenden Fall deutlich steigender CO2-Preise sollte die Bundesregierung schon vor 2023 die institutionellen Voraussetzungen für die Umsetzung des Klimagelds wie im Koalitionsvertrag beschrieben schaffen. Nationaler CO2-Mindestpreis: Bis spätestens 2025 sollte ein Mindestpreis zur eventuellen Ergänzung eines EU ETS-II vorbereitet und ggf. implementiert werden. Dadurch kann im Fall anfänglich niedriger Preise im EU ETS-II garantiert werden, dass der CO2-Preis in Deutschland weiterhin kontinuierlich ansteigt. Neben diesen Maßnahmen auf nationaler Ebene, sollte sich die Bundesregierung in den Fit-for-55 Verhandlungen einsetzen (1) für die Flexibilität zwischen EU ETS und ESR sowie (2) für ein graduelles Linking zwischen ETS-I und ETS-II. Mit beiden Maßnahmen können die sehr hohen Preisunterscheide reduziert und die Effizienz der Klimapolitik erhöht werden.

Description: Zusammenfassung 1. Einleitung 2. Zwei Unsicherheiten 3. Eckpunkte und No-Regret Optionen 4. Implikationen für die Fit-for-55 Verhandlungen

Description: Dieses Kurzdossier analysiert die Auswirkungen der Energiekrise auf die Transformation des deutschen Energiesystems zur Klimaneutralität 2045 sowie Strategien zur Beseitigung der Abhängigkeit Deutschlands von russischen Erdgasimporten.

Description: Im Sommer 2021 wurde zur Etablierung des Wärme- & Wohnen-Panels des Kopernikus-Projekts Ariadne die erste von drei jährlichen Erhebungen unter ca. 15.000 Haushalten durchgeführt. Die wiederholte systematische Befragung derselben Haushalte gestattet eine fundierte Evaluierung der Effektivität klimapolitischer Maßnahmen im Wärmesektor, da dabei erstmals Informationen zum Gebäudebestand und dem Endenergiebedarf mit detaillierten Angaben zu den sozioökonomischen Charakteristika der Haushalte verknüpft werden. Darüber hinaus werden die Präferenzen der Haushalte hinsichtlich verschiedener Klimaschutzinstrumente im Gebäudesektor ermittelt, wie zum Beispiel das Einbauverbot von Ölheizungen oder die Förderung von energieeffizienten Heizungsanlagen. Mit dem Wärme- & Wohnen-Panel wird eine einzigartige Datengrundlage geschaffen, die für die Evaluierung dieser Klimaschutzinstrumente unverzichtbar ist. Neben einer umfassenden Abfrage der Gebäudecharakteristika und Heiztechnik, auf Grundlage derer der Energiebedarf der Haushalte berechnet werden kann, lag der Schwerpunkt der ersten Erhebungswelle auf den energetischen Modernisierungstätigkeiten privater Haushalte sowie auf der Bewertung und Akzeptanz von Klimaschutzinstrumenten im Gebäudesektor. Des Weiteren wurde die Akzeptanz verschiedener Aufteilungsvarianten der Kostenbelastung der CO2- Bepreisung auf Mietende und Vermietende untersucht. Zu den bedeutendsten Ergebnissen gehört die geringe Informiertheit der an der Befragung Teilnehmenden über die CO 2-Bepreisung, ein Klimaschutzinstrument, dessen Effektivität wesentlich davon abhängt, wie gut die Bürgerinnen und Bürger darüber informiert sind. Mit einem Anteil von 46,7% gibt jedoch ein großer Teil aller Befragten an, sich eher nicht informiert zu fühlen, 13% fühlen sich gar überhaupt nicht informiert. Sehr gut informiert fühlt sich nur ein sehr geringer Teil von 3,4% der Befragten. Eine Aufteilung der Kostenbelastung der CO2- Bepreisung gemäß Bausubstanz, bei der der Kostenanteil, den Vermietende tragen, umso niedriger ist, je höher die Energieeffizienz eines Gebäudes ist, genießt jeweils die höchste Zustimmung unter den befragten Mietenden und Vermietenden. Einer hälftigen Kostenaufteilung zwischen Mietenden und Vermietenden wird von diesen beiden Gruppen zu jeweils rund 40% zugestimmt, während die vollständige Kostenübernahme durch Mietende oder Vermietende durch die jeweils Kostentragenden abgelehnt wird.

Description: Lange et al. (2020) used global climate models and global hydrological models to project how global warming might change the exposure of land and population to droughts around the world. A summary of that study including results at the global and national level is provided in the associated global ISIpedia article. Here we present additional results at the national and grid level for Turkey. Important limitations of these country-specific results are discussed in the last section of this report.

Description: Die Kommission hat ihr “Fit For 55” Paket vorgelegt, welches das 55%-Reduktionsziel für 2030 wie folgt auf die Sektoren aufteilt: Die Sektoren im bestehenden EU-Emissionshandelssystem (ETS), also hauptsächlich Strom und Industrie, sollen ihre Emissionen um 61% gegenüber 2005 mindern. Alle anderen Sektoren fallen unter die Effort Sharing Regulation (ESR) und sollen ihre Emissionen um 40% gegenüber 2005 mindern. In diesem Papier analysieren wir die notwendigen CO2-Preise zur Zielerreichung unter der Annahme, dass eine Bepreisung von CO2 das einzige Instrument der Emissionsminderung ist. Werden weitere Politikinstrumente eingesetzt, zum Beispiel Technologiestandards, dann können zwar die CO2-Preise abgesenkt und die Verteilung der Vermeidungskosten auf Haushalte und Unternehmen verändert werden; jedoch kann das Niveau der gesamtwirtschaftlichen Vermeidungskosten nur dann vermindert werden, wenn die zusätzlichen Politikinstrumente bestehende Marktversagen verringern und dabei nicht mehr neue Ineffizienzen schaffen. Die notwendigen CO2-Preise im Jahre 2030 erreichen dabei 275 EUR/t in den ESR-Sektoren (Bandbreite: 210-405 EUR/t). Diese Preise sind mehr als doppelt so hoch wie die für das ETS-Ziel notwendigen CO2-Preise (130 EUR/t, Bandbreite 95-210 EUR/t). Allerdings wird die Höhe der notwendigen CO2-Preise maßgeblich davon beeinflusst, a) wie die Emissionsminderungen zwischen ETS und ESR aufgeteilt werden, b) wie schnell der Markthochlauf emissionsfreier Technologien – insbesondere der Elektromobilität – realisiert wird und wie schnell Wind- und Solarstrom ausgebaut, sowie die notwendigen Flexibilitäten im Stromsystem durch Netzausbau, Speicher und Lastmanagement bereitgestellt werden können. Für den Fall, dass der ETS 50% der zusätzlichen Minderungen des ESR übernimmt, gleichen sich beide Preise stark an: 190 EUR/t im ETS und 195 EUR/t in der ESR. Für die Politikinstrumente ergeben sich zwei Schlussfolgerungen: Ein höherer Vermeidungsbeitrag der ETS-Sektoren könnte die CO2-Preise angleichen, und somit das 2030-Ziel kostengünstiger erreichen. Allerdings könnte eine solche Aufteilung auch zu sehr hohen ESR-CO2-Preisen zu einem späteren Zeitpunkt führen, falls kurzfristig niedrigere CO2-Preise in den ESR-Sektoren den Markthochlauf emissionsfreier Technologien ausbremsen. Dies wird aber nur dann der Fall sein, wenn der langfristige Pfad der CO2-Preise von den Investoren als nicht glaubwürdig wahrgenommen wird. Die Kostenersparnisse hängen sowohl von den Erwartungen der Investoren als auch davon ab, welche zusätzlichen Maßnahmen noch auf europäischer und nationaler Ebene implementiert werden, die die Glaubwürdigkeit der langfristigen Zielerreichung stärken. Die große Bandbreite der notwendigen CO2-Preise je nach Annahmen zum Markthochlauf zeigt die Bedeutung von komplementärem Infrastrukturausbau und Technologiepolitik. So könnten beispielsweise der Ausbau der Ladeinfrastruktur und Investitionsanreize den Markthochlauf emissionsfreier Technologien fördern. Solche Maßnahmen – wie sie auch im Fit-for-55 Paket der EU Kommision vorgesehen sind – können bestehende Marktversagen korrigieren und so den notwendigen CO2-Preis senken sowie die Sicherheit der Klimazielerreichung erhöhen. Allerdings gehen diese Maßnahmen oftmals mit versteckten Kosten einher, und ein sozialer Ausgleich ist zudem schwerer möglich, da keine Einnahmen aus der CO2-Bepreisung zur Verfügung stehen.

Description: In order to better understand the role of fluids during subduction and subsequent exhumation, we have investigated whole-rock and mineral chemistry (major and trace elements) and Li, B as well as O, Sr, Nd, Pb isotopes on selected continuous drill-core profiles through contrasting lithological boundaries from the Chinese Continental Scientific Drilling Program (CCSD) in Sulu, China. Four carefully selected sample sets have been chosen to investigate geochemical changes as a result of fluid mobilization during dehydration, peak metamorphism, and exhumation of deeply subducted continental crust. Our data reveal that while O and Sr-Nd-Pb isotopic compositions remain more or less unchanged, significant Li and/or B isotope fractionations occur between different lithologies that are in close contact during various metamorphic stages. Samples that are supposed to represent prograde dehydration as indicated by veins formed at high pressures (HP) are characterized by element patterns of highly fluid-mobile elements in the veins that are complementary to those of the host eclogite. A second sample set represents a UHP metamorphic crustal eclogite that is separated from a garnet peridotite by a thin transitional interface. Garnet peridotite and eclogite are characterized by a 〉10% difference in MgO, which, together with the presence of abundant hydroxyl-bearing minerals and compositionally different clinopyroxene grains demonstrate that both rocks have been derived from different sources that have been tectonically juxtaposed during subduction, and that hydrous silicate-rich fluids have been added from the subducting slab to the mantle. Two additional sample sets, comprising retrograde amphibolite and relatively fresh eclogite, demonstrate that besides external fluids, internal fluids can be responsible for the formation of amphibolite. Li and B concentrations and isotopic compositions point to losses and isotopic fractionation during progressive dehydration. On the other hand, fluids with isotopically heavier Li and B are added during retrogression. On a small scale, mantle-derived rocks may be significantly metasomatized by fluids derived from the subducted slab. Our study indicates that during high-grade metamorphism, Li and B may show different patterns of enrichment and of isotopic fractionation.

Description: The Itajaí Basin located in the southern border of the Luís Alves Microplate is considered as a peripheral foreland basin related to the Dom Feliciano Belt. It presents an excellent record of the Ediacaran period, and its upper parts display the best Brazilian example of Precambrian turbiditic deposits. The basal succession of Itajaí Group is represented by sandstones and conglomerates (Baú Formation) deposited in alluvial and deltaic-fan systems. The marine upper sequences correspond to the Ribeirão Carvalho (channelized and non-channelized proximal silty-argillaceous rhythmic turbidites), Ribeirão Neisse (arkosic sandstones and siltites), and Ribeirão do Bode (distal silty turbidites) formations. The Apiúna Formation felsic volcanic rocks crosscut the sedimentary succession. The Cambrian Subida leucosyenogranite represents the last felsic magmatic activity to affect the Itajaí Basin. The Brusque Group and the Florianópolis Batholith are proposed as source areas for the sediments of the upper sequence. For the lower continental units the source areas are the Santa Catarina, São Miguel and Camboriú complexes. The lack of any oceanic crust in the Itajaí Basin suggests that the marine units were deposited in a restricted, internal sea. The sedimentation started around 600 Ma and ended before 560 Ma as indicated by the emplacement of rhyolitic domes. The Itajaí Basin is temporally and tectonically correlated with the Camaquã Basin in Rio Grande do Sul and the Arroyo del Soldado/Piriápolis Basin in Uruguay. It also has several tectono-sedimentary characteristics in common with the African-equivalent Nama Basin.

Description: Most studies dealing with material properties of sandstones are based on a small data set. The present study utilizes petrographical and petrophysical data from 22 selected sandstones and ~300 sandstones from the literature to estimate/predict the material and weathering behaviour of characteristic sandstones. Composition and fabric properties were determined from detailed thin section analyses. Statistical methods applied consist of data distributions with whisker plots and linear regression with confidence regions for the petrophysical and weathering properties. To identify similarities between individual sandstones and to define groups of specific sandstone types, principal component and cluster analyses were applied. The results confirm an interaction between the composition, depositional environment, stratigraphic association and diagenesis, which leads to a particular material behaviour of sandstones. Three different types of pore radii distributions are observed, whereby each is derived from different pore space modifications during diagenesis and is associated with specific sandstone types: (1) bimodal with a maximum in capillary and micropores, (2) unimodal unequal with a maximum in smaller capillary pores and (3) unimodal equable with a maximum in larger capillary pores. Each distribution shows specific dependencies to water absorption, salt loading and hygric dilatation. The strength–porosity relationship shows dependence on the content of unstable lithic fragments, grain contact and type of pore radii distribution, cementation and degree of alteration. Sandstones showing a maximum of capillary pores and micropores (bimodal) exhibit a distinct hygric dilatation and low salt resistance. These sandstones are highly immature sublitharenites–litharenites, characterized by altered unstable rock fragments, which show pointed-elongated grain contacts, and some pseudomatrix. Quartz arenites and sublitharenites–litharenites which are strongly compacted and cemented, show unimodal unequal pore radii distributions, low porosity, high strength and a high salt resistance. The presence of swellable clay minerals in sublitharenites–litharenites leads to a medium to high hygric dilatation, whereas quartz arenites show little hygric dilatation. Sandstones with unimodal equal pore radii distribution mostly belong to weakly compacted and cemented mature quartz arenites. These are characterized by high water absorption and high porosity, low to medium strength and a low salt resistance. The data compiled in this study are used to create a sandstone quality catalogue. Since material properties are dependent on many different parameters of influence, the transition between different lithotypes is fluent.

Description: The lattice-preferred orientation (LPOs) of two late-Variscan granitoids, the Meissen monzonite and the Podlesí dyke granite, were determined from high-resolution time-of-flight neutron diffraction patterns gained at the diffractometer SKAT in Dubna, Russia. The results demonstrate that the method is suitable for the LPO analysis of polyphase, relatively coarse-grained (0.1–6 mm) rocks. The Meissen monzonite has a prominent shape-preferred orientation (SPO) of the non-equidimensional minerals feldspar, mica and amphibole, whereas SPO of the Podlesí granite is unapparent at the hand-specimen scale. The neutron diffraction data revealed distinct LPOs in both granitoids. The LPO of the non-equidimensional minerals feldspar, mica and amphibole developed mainly during magmatic flow. In the case of the Meissen monzonite, the magmatic flow was superimposed by regional shear tectonics, which, however, had no significant effect on the LPOs. In both samples, quartz shows a weak but distinct LPO, which is atypical for plastic deformation and different in the syn-kinematic Meissen monzonite and the post-kinematic Podlesí granite. We suggest that, first of all, the quartz LPO of the Meissen monzonite is the result of oriented growth in an anisotropic stress field. The quartz LPO of the Podlesí granite, which more or less resembles a deformational LPO in the flattening field of the local strain field, developed during magmatic flow, whereby the rhombohedral faces of the quartz crystals adhered to the (010) faces of aligned albite and to the (001) faces of zinnwaldite. Due to shape anisotropy of their attachments, the quartz crystals were passively aligned by magmatic flow. Thus, magmatic flow and oriented crystal growth are the major LPO-forming processes in both granitoids. For the Meissen monzonite, the solid-state flow was too weak to cause significant crystallographic re-orientation of the minerals aligned by magmatic flow. Finally, the significance of our results for the evaluation of the regional tectonic environment during magma emplacement is discussed. The discussion on the regional implications of the more methodologically oriented results provides the basis for future, more regionally aimed studies in view of the fabric characteristics of such plutons and their developing mechanisms.

Description: The Eastern Sierras Pampeanas were structured by three main events: the Ediacaran to early Cambrian (580–510 Ma) Pampean, the late Cambrian–Ordovician (500–440 Ma) Famatinian and the Devonian-Carboniferous (400–350 Ma) Achalian orogenies. Geochronological and Sm–Nd isotopic evidence combined with petrological and structural features allow to speculate for a major rift event (Ediacaran) dividing into two Mesoproterozoic major crustal blocks (source of the Grenvillian age peaks in the metaclastic rocks).This event would be coeval with the development of arc magmatism along the eastern margin of the eastern block. Closure of this eastern margin led to a Cambrian active margin (Sierra Norte arc) along the western margin of the eastern block in which magmatism reworked the same crustal block. Consumption of a ridge segment (input of OIB signature mafic magmas) which controlled granulite-facies metamorphism led to a final collision (Pampean orogeny) with the western Mesoprotrozoic block. Sm–Nd results for the metamorphic basement suggest that the TDM age interval of 1.8–1.7 Ga, which is associated with the less radiogenic values of εNd(540) (−6 to −8), can be considered as the mean average crustal composition for the Eastern Sierras Pampeanas. Increasing metamorphic grade in rocks with similar detrital sources and metamorphic ages like in the Sierras de Córdoba is associated with a younger TDM age and a more positive εNd(540) value. Pampean pre-540 Ma granitoids form two clusters, one with TDM ages between 2.0 and 1.75 Ga and another between 1.6 and 1.5 Ga. Pampean post-540 Ma granitoids exhibit more homogenous TDM ages ranging from 2.0 to 1.75 Ga. Ordovician re-activation of active margin along the western part of the block that collided in the Cambrian led to arc magmatism (Famatinian orogeny) and related ensialic back-arc basin in which high-grade metamorphism is related to mid-crustal felsic plutonism and mafic magmatism with significant contamination of continental crust. TDM values for the Ordovician Famatinian granitoids define a main interval of 1.8–1.6, except for the Ordovician TTG suites of the Sierras de Córdoba, which show younger TDM ages ranging from 1.3 to 1.0 Ga. In Devonian times (Achalian orogeny), a new subduction regime installed west of the Eastern Sierras Pampeanas. Devonian magmatism in the Sierras exhibit process of mixing/assimilation of depleted mantle signature melts and continental crust. Achalian magmatism exhibits more radiogenic εNd(540) values that range between 0.5 and −4 and TDM ages younger than 1.3 Ga. In pre-Devonian times, crustal reworking is dominant, whereas processes during Devonian times involved different geochemical and isotopic signatures that reflect a major input of juvenile magmatism.

Description: The expansion processes that develop in building stones upon changes of moisture content may be an important contributing factor for their deteriorations. Until recently, few data could be found in the literature concerning this parameter and weathering processes. Moreover, the processes that may be responsible for the moisture related expansion of natural building stones are not yet completely understood. To further elucidate this process, extensive mineralogical, petrophysical and fabric investigations were performed on eight German sandstones in order to obtain more information regarding the weathering process and its dependence on the rock fabric. The analysed sandstones show a wide range of pore size distributions and porosities. A positive correlation with the fabric and the pore space can be found for all studied petrophysical parameters. The intensity of the expansion and related swelling pressure cannot be attributed only to the swelling of clay minerals. The investigations suggest that the micropores and the resulting disjoining pressure during wet/dry cycles also play an important role. The results obtained suggest that the mechanism is related to the presence of liquid water within the porous material.

Description: The profitable production of dimension stone mainly depends on the extractable block size. The regularity and volume of the blocks are of critical importance, and are controlled by the three-dimensional pattern of the discontinuity system. Therefore, optimization of block size has to be the aim when quarrying for natural stone. This is mainly connected to the quantification of joints and fractures, i.e., their spacing and orientation. The problem of finding unfractured blocks within arbitrarily oriented and distributed planes can be solved effectively by a numerical algorithm. The main effects of joint orientations on block sizes and shapes will be presented in this article. Quantification of unfractured blocks with the aim of optimization is illustrated by detailed studies on several quarries. The algorithm used in this study can be applied as a powerful tool in the planning of a quarry and the future exploitation of dimension stone. Application of the described approach is demonstrated on practical examples of quarrying natural stones, namely, sandstone, granite, rhyolite, etc. Block quarrying can be optimized by using the new 3D-BlockExpert approach. The quantification of unfractured rock masses is also shown to contribute to a more ecological protection and the sustainable use of natural resources.

Description: Damages to natural building stones induced by the action of frost are considered to be of great importance. Commonly, the frost resistance of building stones is checked by standardised freeze–thaw tests before using. Corresponding tests normally involve 30–50 freeze–thaw action cycles. In order to verify the significance of such measurements, we performed long-term tests on four selected rocks over 1,400 freeze–thaw action cycles. Additionally, numerous petrophysical parameters were analysed to compare the behaviour of rocks in the weathering tests according to the current explanatory models of stress formation by growing ice crystals in the pore space. The long-term tests yield more information about the real frost sensibility of the rocks. A clear deterioration cannot be determined in most cases until 50 weathering cycles have been completed. In the freeze–thaw tests, the samples are also stressed by changing temperature and moisture, indicating that different decay mechanisms can interfere with each other. Thus, thermohygric and moisture expansion are important damage processes.

Description: Owing to its long building history, different types of building stones comprised the construction of the Cologne Cathedral. Severe damage is observed on the different stones, e.g., sandstones, carbonate, and volcanic rocks, especially when the different stone materials neighbor the medieval “Drachenfels trachyte” from the “Siebengebirge”. The question arises, “Is the insufficient compatibility of the implemented building materials causatively related to the strong decay of the Drachenfels trachyte?” The present investigations focus on the petrography and mineralogical composition of eight different stones from the Cologne Cathedral. Petrophysical data, i.e., phase content, moisture and thermal characteristics as well as strength properties are determined and discussed in correlation to each other, showing that not only in terms of lithology great differences exist, but also the petrophysical properties strongly diverge. The ascertained parameters are discussed in view of the deterioration behavior and decay mechanisms of the different stones. To evaluate the compatibility of original, replacement and modern building materials, the properties of the investigated stones are compared to those of Drachenfels trachyte by means of constraints given in the literature. Besides optical properties, petrophysical criteria are also defined as well as strength values. It could be shown that primarily moisture properties, i.e., capillary and sorptive water uptake, water saturation, drying processes and moisture dilatation can be addressed to the deterioration processes.

Description: The range of substrates that the bone-eating marine worm Osedax is able to consume has important implications for its evolutionary history, especially its potential link to the rise of whales. Once considered a whale specialist, recent work indicates that Osedax consumes a wide range of vertebrate remains, including whale soft tissue and the bones of mammals, birds and fishes. Traces resembling those produced by living Osedax have now been recognized for the first time in Oligocene whale teeth and fish bones from deep-water strata of the Makah, Pysht and Lincoln Creek formations in western Washington State, USA. The specimens were acid etched from concretions, and details of the borehole morphology were investigated using micro-computed tomography. Together with previously published Osedax traces from this area, our results show that by Oligocene time Osedax was able to colonize the same range of vertebrate remains that it consumes today and had a similar diversity of root morphologies. This supports the view that a generalist ability to exploit vertebrate bones may be an ancestral trait of Osedax.

Description: The formation of ring faults yields important implications for understanding the structural and dynamic evolution of collapse calderas and potentially associated ash-flow eruptions. Caldera collapse occurred in 2000 at Miyakejima Island (Japan) in response to a lateral intrusion. Based on geophysical data it is inferred that a set of caldera ring faults was propagating upward. To understand the kinematics of ring-fault propagation, linkage, and interaction, we describe new laboratory sand-box experiments that were analyzed through Digital Image Correlation (DIC) and post-processed using 2D strain analysis. The results help us gain a better understanding of the processes occurring during caldera subsidence at Miyakejima. We show that magma chamber evacuation induces strain localization at the lateral chamber margin in the form of a set of reverse faults that sequentially develops and propagates upwards. Then a set of normal faults initiates from tension fractures at the surface, propagating downwards to link with the reverse faults at depth. With increasing amounts of subsidence, interaction between the reverse- and normal-fault segments results in a deactivation of the reverse faults, while displacement becomes focused on the outer normal faults. Modeling results show that the area of faulting and collapse migrates successively outward, as peak displacement transfers from the inner ring faults to later developed outer ring faults. The final structural architecture of the faults bounding the subsiding piston-like block is hence a consequence of the amount of subsidence, in agreement with other caldera structures observed in nature. The experimental simulations provide an analogy to the observations and seismic records of caldera collapse at Miyakejima volcano, but are also applicable to caldera collapse in general.

Description: Forests in lowland Bolivia suffer from severe deforestation caused by different types of agents and land use activities. We identify three major proximate causes of deforestation. The largest share of deforestation is attributable to the expansion of mechanized agriculture, followed by cattle ranching and small-scale agriculture. We utilize a spatially explicit multinomial logit model to analyze the determinants of each of these proximate causes of deforestation between 1992 and 2004. We substantiate the quantitative insights with a qualitative analysis of historical processes that have shaped land use patterns in the Bolivian lowlands to date. Our results suggest that the expansion of mechanized agriculture occurs mainly in response to good access to export markets, fertile soil, and intermediate rainfall conditions. Increases in small-scale agriculture are mainly associated with a humid climate, fertile soil, and proximity to local markets. Forest conversion into pastures for cattle ranching occurs mostly irrespective of environmental determinants and can mainly be explained by access to local markets. Land use restrictions, such as protected areas, seem to prevent the expansion of mechanized agriculture but have little impact on the expansion of small-scale agriculture and cattle ranching. The analysis of future deforestation trends reveals possible hotspots of future expansion for each proximate cause and specifically highlights the possible opening of new frontiers for deforestation due to mechanized agriculture. Whereas the quantitative analysis effectively elucidates the spatial patterns of recent agricultural expansion, the interpretation of long-term historic drivers reveals that the timing and quantity of forest conversion are often triggered by political interventions and historical legacies.

Description: The Mantiqueira Province represents a series of supracrustal segments of the South-American counterpart formed during the Gondwana Supercontinent agglutination. In this crustal domain, the process of escape tectonics played a conspicuous role, generating important NE–N–S-trending lineaments. The oblique component of the motions of the colliding tectonic blocks defined the transpressional character of the main suture zones: Lancinha-Itariri, Cubatão-Arcádia-Areal, Serrinha-Rio Palmital in the Ribeira Belt and Sierra Ballena-Major Gercino in the Dom Feliciano Belt. The process as a whole lasted for ca. 60 Ma, since the initial collision phase until the lateral escape phase predominantly marked by dextral and subordinate sinistral transpressional shear zones. In the Dom Feliciano Belt, southern Brazil and Uruguay, transpressional event at 630–600 Ma is recognized and in the Ribeira Belt, despite less coevally, the transpressional event occurred between 590 and 560 Ma in its northern-central portion and between ca. 625 and 595 Ma in its central-southern portion. The kinematics of several shear zones with simultaneous movement in opposite directions at their terminations is explained by the sinuosity of these lineaments in relation to a predominantly continuous westward compression.

Description: The Sierras Pampeanas in central and north-western Argentina constitute a distinct morphotectonic feature between 27°S and 33°S. The last stage of uplift and deformation in this area are interpreted to be closely related to the Andean flat-slab subduction of the Nazca plate beneath the South American plate. K–Ar fault gouge dating and low-temperature thermochronology along two transects within the Sierra de Comechingones reveal a minimum age for the onset of brittle deformation about 340 Ma, very low exhumation rates since Late Paleozoic time, as well as a total exhumation of about 2.3 km since the Late Cretaceous. New Ar–Ar ages (7.54–1.91 Ma) of volcanic rocks from the San Luis volcanic belt support the eastward propagation of the flat-slab magmatic front, confirming the onset of flat-slab related deformation in this region at 11.2 Ma. Although low-temperature thermochronology does not clearly constrain the signal of the Andean uplift, it is understood that the current structural relief related to the Comechingones range has been achieved after the exhumation of both fault walls (circa 80–70 Ma).

Description: The Palaeogene was the most recent greenhouse period on Earth. Especially for the Late Palaeocene and Early Eocene, several superimposed short-term hyperthermal events have been described, including extremes such as the Palaeocene–Eocene Thermal Maximum. Major faunal and floral turnovers in the marine and terrestrial realms were recorded in association with these events. High-resolution palynological analysis of the early Middle Eocene maar lake sediments at Messel, near Darmstadt, Germany, provides an insight into the dynamics of a climax vegetation during the Middle Eocene greenhouse climate in a time span without significant climatic excursions. Numerical techniques like detrended correspondence analysis and wavelet analysis have been applied to recognize cyclic fluctuations and long-term trends in the vegetation through a time interval of approximately 640 kyr. Based on the numerical zoning of the pollen diagram, three phases in the development of the vegetation may be distinguished. Throughout these phases, the climax vegetation did not change substantially in qualitative composition, but a trend towards noticeably less humid conditions probably in combination with a drop of the water level in the lake may be recognized. A shift in algal population from the freshwater dinoflagellate cyst Messelodinium thielepfeifferae to a dominance of Botryococcus in the uppermost part of the core is interpreted as a response to changes in acidity and nutrient availability within the lake. Time series analyses of pollen assemblages show that variations in the Milankovitch range of eccentricity, obliquity and precession can be distinguished. In addition, fluctuations in the sub-Milankovitch range are indicated. This demonstrates that floral changes during steady depositional conditions in the Middle Eocene of Messel were controlled by orbital forcing.

Description: In the presented case study, ascomycete fungi and green algae on a marble monument were identified by comparisons of the 18S rRNA gene sequences, which were obtained from DNA either from environmental samples or from enrichment cultures. The organisms were found to be responsible for either black or green surface coverings on different areas of the monument surface. Most fungi were related to plant-inhabiting genera, corresponding to a heavy soiling of the marble surface with honeydew. Whereas green algae of the genera Stichococcus, Chloroidium and Apatococcus were found to be dominant in all samples, isolates of two additional genera were recovered only from enrichment cultures. A reference strain of Apatococcus lobatus and an isolate of Prasiolopsis sp. were investigated with respect to putative surface adhesive structures of the cell envelope. The Prasiolopsis cell walls were covered with a thin adhesive exopolysaccharide layer involved in biofilm formation.

Description: Bowing is a well-known phenomenon seen in marbles used as building veneers. This form of rock weathering occurs as a result of external factors such as temperature, humidity, the system for anchoring the marble slabs or the panel dimensions. Under the same external conditions, many factors will determine the degree of deformation including petrography, thermal properties and residual locked stresses. The usual way to solve the problem of bowed marble slabs is to replace them with other materials, such as granites, in which the deformation still exists but is less common. In this study, eight ornamental granites with different mineralogy, grain size, grain shape, porosity and fabric were tested in a laboratory to assess their susceptibility to bowing. Three slabs of granite, each cut with a different orientation, were studied under different conditions of temperature (90 and 120°C) and water saturation (dry and wet) to investigate the influence of these factors together with that of anisotropy. At 90°C, only the granite with the coarsest grain size and low porosity exhibited deformation under wet conditions. At 120°C and wet conditions, three of the granites showed evident signs of bowing. Again, the granite with the coarsest grain size was the most deformed. It was concluded that the wide grain size distribution influences microcracking more than other expected factors, such as the quartz content of the rock. Also, mineral shape-preferred orientation and porosity play an important role in the bowing of the studied granites.

Description: The emplacement of the Mesoproterozoic Götemar Pluton into Paleoproterozoic granitoid host rocks of the Transscandinavian Igneous Belt is re-examined by microfabric analysis, including cathodoluminescence microscopy. Field data on the pluton-host rock system are used to strengthen the model. The Götemar Pluton, situated on the Baltic Shield of SE Sweden, is a horizontally zoned tabular structure that was constructed by the intrusion of successive pulses of magma with different crystal/melt ratios, at an estimated crustal depth of 4–8 km. Initial pluton formation involved magma ascent along a vertical dike, which was arrested at a mechanical discontinuity within the granitoid host rocks; this led to the formation of an initial sill. Subsequent sill stacking and their constant inflation resulted in deformation and reheating of existing magma bodies, which also raised the pluton roof. This multi-stage emplacement scenario is indicated by complex dike relationships and the occurrence of several generations of quartz (Si-metasomatism). The sills were charged by different domains of a heterogeneous magma chamber with varying crystal/melt ratios. Ascent or emplacement of magma with a high crystal/melt ratio is indicated by syn-magmatic deformation of phenocrysts. Complex crystallization fabrics (e.g. oscillatory growth zoning caused by high crystal defect density, overgrowth and replacement features, resorbed and corroded crystal cores, rapakivi structure) are mostly related to processes within the main chamber, that is repeated magma mixing or water influx.

Description: Slates are internationally known as roof and façade-cladding material since prehistoric times. The methods required to mine and manufacture these dimensional stones are relatively simple in comparison to those utilized in granitic dimensional stones. This has led to a worldwide rentable commercialization of slate in the last centuries and also to the development of characteristic cultural landscapes. In Uruguay several slates are mined and used in architecture, especially as façade cladding and floor slabs. The most important slates regarding their production and utilization are the dolomitic slates. These dolomitic slates are associated with the Neoproterozoic thrust and fold belt of the Dom Feliciano belt. Representative samples have been geochemically and petrographically characterized, as well as petrophysically and petromechanically analyzed. The petrophysical and petromechanical properties were investigated in a very systematic way with respect to the new European standards, showing values comparable to those registered for internationally known slates. Detailed structural and deposit analysis were carried out in Uruguay in order to evaluate the dolomitic slate deposits. The slates are linked to calc-silicate strata in a greenschist facies volcano-sedimentary sequence and the deposits are located in the limb of a regional fold, where bedding and cleavage are parallel. The main lithotype is a layered and fine-grained dolomitic slate with a quite diverse palette of colors: light and dark green, gray, dark gray, reddish and black. The mined slate is split into slabs 0.5–2 cm thick. In the past, the average production in Uruguay was around 4,000 tons/year and a historical maximum of 13,000 tons was reached in 1993 (Oyhantçabal et al. in Z dt Ges Geowiss 158(3):417–428, 2007). The oscillations in the regional demand were the cause of several flourishing and decay cycles in the activity, but our investigation shows a considerable volume of indicated resources and therefore a very good potential.

Description: Microstructure‐based finite-element analysis with a microcracking algorithm was used to simulate an actual degradation phenomenon of marble structures, i.e., microcracking. Both microcrack initiation and crack propagation were characterized, as were their dependence on lattice preferred orientation (LPO), grain shape preferred orientation (SPO), grain size, marble composition (calcite and dolomite) and grain‐boundary fracture toughness. Two LPOs were analyzed: a random orientation distribution function and an orientation distribution function with strong directional crystalline texture generated from a March–Dollase distribution. Three SPOs were considered: equiaxed grains; elongated grains and a mixture of equiaxed and elongated grains. Three different grain sizes were considered: fine grains of order 200 μm (only calcitic marble); medium size grains of order 1 mm (calcitic and dolomitic marbles); and large grains of order 2 mm (only dolomitic marble). The fracture surface energy for the grain boundaries, γig, was chosen to be 20 and 40 % of the fracture surface energy of a grain, γxtal, so that both intergranular and transgranular fracture were possible. Studies were performed on these idealized marble microstructures to elucidate the range of microcracking responses. Simulations were performed for both heating and cooling by 50 °C in steps of 1 °C. Microcracking results were correlated with the thermoelastic responses, which are indicators related to degradation. The results indicate that certain combinations of LPO, SPO, grain size, grain‐boundary fracture toughness and marble composition have a significant influence on the thermal-elastic response of marble. Microstructure with the smallest grain size and the highest degree of SPO and LPO had less of a tendency to microcrack. Additionally, with increasing SPO and LPO microcracking becomes more spatially anisotropic. A significant observation for all microstructures was an asymmetry in microcracking upon heating and cooling: more microcracking was observed upon cooling than upon heating. Given an identical microstructure and crystallographic texture, calcite showed larger thermal stresses than dolomite, had an earlier onset of microcracking upon heating and cooling, and a greater microcracked area at a given temperature differential. Thermal expansion coefficients with and without microcracking were also determined.

Description: In Uruguay commercial granite varieties comprise mafic rocks, granitoids, and syenitoids. There is a long tradition in Uruguay, as well as worldwide, of using dimensional stones in architecture and art, specially granitic ones. Some of the present applications of these dimensional stones are as façade cladding, countertops, and outdoor and indoor floor slabs. The color spectrum of the Uruguayan granitic dimensional stones varies from black to light gray, covering a wide variety of red and pink and minor greenish-gray. The décor of these granitic dimensional stones is mainly determined by their fabric, fundamentally the grain size and the color distribution between the different minerals that compose the rocks. In the present research the most important commercial granites were sampled to analyze their petrography and petrophysical properties. A detailed structural analysis has been performed in several deposits, as well as the application of the software 3D Block Expert for modeling the possible raw block size distribution. Other factors controlling the mining viability of the deposits were also studied (e.g., homogeneity/heterogeneity of color and décor) and the possible reserves were calculated.

Description: The old mining city of Guanajuato in middle Mexico preserves one of the most important historical legacies in colonial buildings, the UNESCO declared the city World Heritage Site in 1988. Practically all the colonial constructions were built with natural stones from the neighbourhood, of which stands a greenish to reddish vulcanite, called Loseros Tuff. Although the Loseros Tuff is widely used in historical buildings in the city. It shows significant deterioration and weathering effects, principally in the parts where the tuff shows a coarse grain size. The petrographic, petrophysical, mineralogical and geochemical properties of the Loseros Tuff were analysed in order to determine the causes, effects, behaviour and response to deterioration of this volcanic rock. The results of the investigations suggest that in addition to the parameters like the grain size and the porosity properties, the pore radii distribution is decisive for the effectiveness of porosity and the water transport into the rock. It is recognized that once the liquid water invades the rock the dissolution of the matrix occurs, which is accompanied by a sudden moisture expansion favoured by the newly formed secondary porosity and the high content of expandable clay minerals.

Description: Kurzfassung Die Quantifizierung der Schadstofffrachten an Kontrollebenen ist eine entscheidende Voraussetzung zur Bewertung von Grundwasserschadensfällen und zum Nachweis von Natural Attenuation. Hierzu können zwei verschiedene Erkundungsansätze, die Frachtbestimmung basierend auf der Interpolation von Punktkonzentrationsmessungen sowie Immissionspumpversuche, verwendet werden. Punktkonzentrationsmessungen haben den entscheidenden Nachteil, dass in der Regel nur eine ausreichend große Anzahl sicher stellen kann, dass die gesamte Abstromfahne erfasst wird. Immissionspumpversuche können wiederum relativ hohe Grundwasseraufbereitungs- und Entsorgungskosten verursachen und nur in ausreichend durchlässigen Grundwasserleitern durchgeführt werden. Ein Vergleich der Ergebnisse aus der Anwendung beider Erkundungsansätze kann eine Hilfestellung bei der Konzipierung von Erkundungsmaßnahmen bieten. Daher wurden die Resultate von vier Immissionspumpversuchen mit Messungen in 13, in kurzem Abstand zueinander errichteten, Direct-Push-Messstellen auf dem Gelände eines ehemaligen Gaswerks verglichen. Es konnte festgestellt werden, dass die Vergleichbarkeit der Erkundungsergebnisse je nach Standortsituation stark von der Heterogenität der Verteilung der Schadstoffe im Grundwasserleiter abhängt. Die Studie legt nahe, dass insbesondere bei stark heterogenen Verhältnissen im Grundwasserleiter Immissionspumpversuche bei der Wahl der Erkundungsmethode bevorzugt werden sollten, da die Interpolation von Punktkonzentrationsmessungen selbst im Falle eines relativ engmaschigen Messstellennetzes zu einer großen Erkundungsunsicherheit führen kann.

Description: The quantification of contaminant mass flow rates at control planes is an essential prerequisite for assessing contaminated sites and for providing evidence of natural attenuation. Two different investigation approaches are usually implemented: mass flow estimation based on interpolation of point scale concentration measurements, and integral pumping tests. Point scale concentration measurements have the crucial disadvantage that in general, only a sufficiently dense monitoring network can ensure that the plume is completely covered. On the other hand, integral pumping tests may require expensive groundwater treatment and disposal and are only applicable in sufficiently conductive aquifers. A comparison of results from the application of both approaches can help with respect to the selection of a subsurface investigation method. A former gasworks site was chosen to compare the results of four integral pumping tests and measurements obtained from 13 direct-push-wells, which were installed at a relatively close spacing. The comparison shows that the correlation of the two methods depends strongly on the heterogeneity of the contaminant distribution within the aquifer. The study suggests that especially in the case of heterogeneous settings, integral pumping tests should be chosen for subsurface investigations, as interpolated point scale concentration measurements, even if densely spaced, can still bear a prohibitively high degree of uncertainty.

Description: The degree of weathering in natural stones on buildings and sculptures has been determined for many years in numerous cases by means of ultrasonic measurements. Conclusions concerning the strength of the rock and the type of weathering can thus be drawn. This relationship has not been established for all rock types. Most of the progress utilizing this method has been made in the analysis of marbles, where an increasing degree of weathering shows lower ultrasonic velocities. In the present study, four Carrara marble samples showing similar rock fabrics, but with respect to weathering exhibit considerable differences are investigated. Porosity varies between 0.2 vol. % and ca. 2.4 vol. %, whereby with increasing porosity the pore radii changes as well. Parallel to this the ultrasonic velocities change in dry samples from about 5.5 to 1.6 km/s, respectively. Model calculations reveal that the velocity reduction is caused by cracks with an extremely small aspect ratio of about 0.005 or even less. After a specific loss of strength, however, solution processes can become active, which modify the microcracks and generate an opposite trend. In the process a strong porosity increase correlates to a relatively small velocity reduction. With the presence of water the Vp porosity weathering relationship experiences a considerable modification. Parallel to the reduction of the ultrasonic velocities, it was determined that the mechanical strength (compressive strength, flexural strength, etc.) as well as the static Young’s modulus is reduced almost equally by a progressive advancement of the weathering front. In one case study dealing with tensile strengths, it was clearly documented how tensile cracks develop and propagate in dependence of the rock fabric. The rock mechanical and ultrasonic velocity data were used for stability assessments applied to the marble statuaries from the Schlossbrücke in Berlin. Stability assessments of the sculpture group 4 reveal that some critical parts must be replaced due to safety reasons.

Description: Fabrics of Cambrian sedimentary dykes formed in Proterozoic granites of the Västervik area (Southeast Sweden) evidence repeated opening/filling and mineralisation/cementation events under varying conditions. Diagnostic features include (1) wall-parallel boundaries between epiclastic fillings and (2) early formed dyke sediments that appear as lithoclasts in subsequently formed sedimentary fillings. The psammitic components mostly consist of well-rounded quartz grains related to a coastal environment and fragments from the granitic host rock. Platy calcitic fragments embedded in the epiclastic matrix originally formed as microveins within already-lithified dyke sediments and the adjacent host rock. Convex downward-pointing, internal sagging structures, together with the preferred orientation of compositional boundaries and long axes of grains/rock fragments parallel to the dyke walls, are interpreted as the result of suction-controlled flow of unconsolidated fillings during episodes of downward dyke growth. Pressure solution of quartz grains are evidence of extensional phases with dyke propagation that were interrupted by phases of horizontal compression normal to the dyke walls. The N–S and NE–SW striking sedimentary dykes formed by opening of a pre-existing joint set during NW–SE oriented rifting during the Cambrian.

Description: Moisture expansion in natural building stones is considered one of the most important factors affecting their weathering and deterioration. The processes that may be responsible for the expansion under determinate relative humidity (hygric dilatation) and water-saturated conditions (hydric dilatation) are generally attributed to the presence of swellable clay minerals. In contrast to this assumption, our investigations show that moisture expansion also takes place in volcanic tuff building stones almost free from clay minerals. To provide a deeper understanding of the processes, swelling and deterioration were performed on 14 volcanic tuffs used as important building stones of different ages, compositions and weathering stages from Mexico, Germany and Hungary. The investigations undertaken include extensive chemical, petrophysical and fabric analyses. The samples show a wide range of effective porosity, microporosity, capillary water absorption, moisture expansion, and CEC values. High moisture expansion does not seem to depend on clay mineral content alone. We also observed that there is no significant effect on dilatation if clay minerals are present but only form a thin coat on the outer shell of bigger pores. Moreover, we identified a correlation between microporosity, average pore radius and moisture expansion. The investigations highlight the fact that moisture expansion cannot only be attributed to swellable clay minerals, and suggest that the presence and accumulation of micropores and their average radius and distribution play an important role for non-clay associated swelling intensity, which can most probably be attributed to the disjoining pressure.

Description: Investigation by Raman spectroscopy of samples from different geological settings shows that the occurrence of TiO2 polymorphs other than rutile can hardly be predicted, and furthermore, the occurrence of anatase is more widespread than previously thought. Metamorphic pressure and temperature, together with whole rock chemistry, control the occurrence of anatase, whereas variation of mineral assemblage characteristics and/or fluid occurrence or composition takes influence on anatase trace element characteristics and re-equilibration of relict rutiles. Evaluation of trace element contents obtained by electron microprobe in anatase, brookite, and rutile shows that these vary significantly between the three TiO2 phases. Therefore, on the one hand, an appropriation to source rock type according to Nb and Cr contents, but as well application of thermometry on the basis of Zr contents, would lead to erroneous results if no phase specification is done beforehand. For the elements Cr, V, Fe, and Nb, variation between the polymorphs is systematic and can be used for discrimination on the basis of a linear discriminant analysis. Using phase group means and coefficients of linear discriminants obtained from a compilation of analyses from samples with well-defined phase information together with prior probabilities of groupings from a natural sample compilation, one is able to calculate phase grouping probabilities of any TiO2 analysis containing at least the critical elements Cr, V, Fe, and Nb. An application of this calculation shows that for the appropriation to the phase rutile, a correct-classification rate of 99.5% is obtained. Hence, phase specification by trace elements proves to be a valuable tool besides Raman spectroscopy.

Description: A new U–Pb SHRIMP age of 551 ± 4 Ma on a mylonitic porphyry that intruded into the Sierra Ballena Shear Zone (Southernmost Dom Feliciano Belt, Uruguay) and a review of relevant published data make possible a more refined correlation and reconstruction of Brasiliano/Pan-African transpressional events. Paleogeographic reconstruction, kinematics and timing of events indicate a connection between the shear systems of the Dom Feliciano and Kaoko Belts at 580–550 Ma. Sinistral transpression recorded in shear zones accommodates deformation subsequent to collision between the Congo and Río de la Plata Cratons. The correlation is strengthened by the similarity of magmatic and metamorphic ages in the Coastal Terrane of the Kaoko Belt and the Punta del Este Terrane of the Dom Feliciano Belt. This post-collisional sinistral transpression brought these units near to their final position in Gondwana and explains the different evolution at 550–530 Ma. While in the Kaoko Belt, an extensional episode resulted in exhumation as a consequence of collision in the Damara Belt, in the Dom Feliciano Belt, sinistral transpression occurred associated with the closure of the southern Adamastor Ocean due to Kalahari-Río de la Plata collision.

Description: This study documents the chemical and textural responses of zircon in the Elba igneous complex, with particular reference to the 7- to 7.8-Ma-old Monte Capanne pluton in relation to its coeval volcanic counterpart (Capraia), using BSE imaging and quantitative electron microprobe analyses. The Monte Capanne pluton displays multiple field and geochemical evidence for magma mixing. The samples we have investigated (including monzogranitic, mafic enclave and dyke samples) display similar zircon textures and are associated with an extremely large range of trace and minor element (Hf, Y, HREE, Th, U) compositions, which contrast with relatively simple textures and zoning patterns in zircons from a Capraia dacite. We have used a relatively simple textural classification (patchy zoning, homogenous cores, oscillatory zoning and unzoned zircon) as the basis for discussing the chemical composition and chemical variation within zircons from the Monte Capanne pluton. Based on these data and other works (Dini et al. 2004 in Lithos 78:101–118, 2004) , it is inferred that mixing between metaluminous and peraluminous melts occurred early in the evolution of the Monte Capanne magma chamber. In particular, mixing was responsible for the development of the patchy-zoning texture in the zircon cores, which was associated with reactions between other accessory phases (including monazite, apatite, allanite), which we infer to have significantly affected the Th distribution in zircon. Zircons from the MC pluton displaying “homogeneous cores” have chemical affinities with zircons in the coeval Capraia volcanic system, consistent with the participation of a Capraia-like mantle end-member during mixing. Further zircon growth in the MC pluton produced the oscillatory zoning texture, which records both long-term (crystal fractionation) and transient (recharge with both silicic and mafic magmas) events in a hybrid magma chamber. It is inferred that Hf and the Th/U ratio cannot be used alone to infer magmatic processes due to their dependency on temperature, nor are they a diagnostic feature of xenocrystic grains. This study shows that zircon chemistry coupled with detailed textural analysis can provide a powerful tool to elucidate the complex evolution of a magma system.

Description: The bowing of natural stone panels is especially known for marble slabs. The bowing of granite is mainly known from tombstones in subtropical humid climate. Field inspections in combination with laboratory investigations with respect to the thermal expansion and the bowing potential was performed on two different granitoids (Cezlak granodiorite and Flossenbürg granite) which differ in the composition and rock fabrics. In addition, to describe and explain the effect of bowing of granitoid facade panels, neutron time-of-flight diffraction was applied to determine residual macro- and microstrain. The measurements were combined with investigations of the crystallographic preferred orientation of quartz and biotite. Both samples show a significant bowing as a function of panel thickness and destination temperature. In comparison to marbles the effect of bowing is more pronounced in granitoids at temperatures of 120°C. The bowing as well as the thermal expansion of the Cezlak sample is also anisotropic with respect to the rock fabrics. A quantitative estimate was performed based on the observed textures. The effect of the locked-in stresses may also have a control on the bowing together with the thermal stresses related to the different volume expansion of the rock-forming minerals.

Description: Multi-isotope study including whole-rock Nd–Sr, single zircon Hf, and SIMS δ18O analyses of zircons sheds light on magma sources in the northernmost Arabian–Nubian Shield (ANS) during ~820–570 Ma. Reconnaissance initial Nd and Sr isotope data for the older rocks (~820–740 Ma) reaffirms previous estimates that early crustal evolution in this part of the shield involved some crustal contamination by pre-ANS material. Prominent isotope provinciality is displayed by post-collisional calc-alkaline and alkaline igneous rocks of ~635–570 Ma across a NW-SE transect across basement of the Sinai Peninsula (Egypt) and southern Israel. Silicic rocks of the NW-region are characterized by lower εNd(T)–εHf(T) and higher Sri and δ18O compared with rocks of the SE-region, and the transition between the regions is gradual. Within each region isotope ratios are independent of the extent of magma fractionation, and zircon cores and rims yield similar δ18O values. Comparison with southern segments of the ANS shows that the source for most ~635–570 Ma rocks can be modeled as the isotopically aged lower-intermediate crust in the ANS core (SE-region) and its northern, more contaminated ANS margins (NW-region). Nevertheless, Nd–Sr isotope enrichment of the lithospheric mantle is indicated by some basic magmas of the NW-region displaying the most enriched Nd–Sr isotope compositions. Comparison of Nd and Hf depleted mantle model ages for rocks of the SE-region may indicate that crustal formation events in the ANS geographical core took place at 1.1–1.2 Ga and were followed by crustal differentiation starting at ~0.9 Ga.

Description: Oligoclase and labradorite crystals have been experimentally replaced by albite in an aqueous sodium silicate solution at 600°C and 2 kbars. The replacement is pseudomorphic and is characterised by a sharp chemical interface which progresses through the feldspar while preserving the crystallographic orientation. Reaction rims of albite, up to 50 μm thick, can be readily achieved within 14 days. Re-equilibration of plagioclase in an 18O-enriched sodium- and silica-bearing solution results in oxygen isotope redistribution within the feldspar framework structure. The observed characteristics of the reaction products are similar to naturally albitised plagioclase and are indicative of an interface-coupled dissolution–reprecipitation mechanism. Chemical analyses demonstrate that the albitisation is accompanied by the mobilisation of major, minor and trace elements also including elements such as Al and Ti which are commonly regarded as immobile during hydrothermal alteration. The results contribute to developing our understanding of the close association between large-scale albitisation and secondary ore mineralisation which is common in nature.

Description: The Sierra de San Luis forms the southern tip of the Eastern Sierras Pampeanas in central Argentina. Two narrow belts of low-grade phyllites and quartz arenites, i.e. the San Luis Formation, have accommodated part of the strain-related differential exhumation of the medium- to high-grade metamorphic domains that constitute to the basement complex of the sierra. Eleven phyllite samples were subjected to the K/Ar fine-fraction dating technique. Results are interpreted in relation to the Kübler index of the illites, which indicate epimetamorphic conditions for the majority of the samples. Obtained ages between 330 and 290 Ma cover a period of compressional tectonics in the late Mississippian (Visean/Serpukhovian boundary) followed by the subsidence during the formation of the Paganzo Basin in the provinces of La Rioja and San Luis. These tectonic movements are coincident with the Toco orogeny in northern Chile and southern Bolivia. This suggests that the older K/Ar ages document the compressional stage and that younger ages record the cooling of the basement during the subsequent extensional uplift of the basement.

Description: A review of the lithostratigraphic units in the Río de la Plata Craton and of new and previously published geochronological, isotopic and geophysical data is presented. Sm–Nd TDM model ages between 2.6 and 2.2 Ga characterize the Piedra Alta Terrane of this craton. Crystallization ages between 2.2 and 2.1 Ga for the metamorphic protoliths and 2.1–2.0 Ga for the post-orogenic granitoids indicate juvenile crust, followed by a short period of crustal recycling. Cratonization of this terrane occurred during the late Paleoproterozoic. Younger overprinting is not observed, suggesting it had a thick and strong lithosphere in the Neoproterozoic. A similar scenario is indicated for the Tandilia Belt of Argentina. Sm–Nd TDM model ages for the Nico Pérez Terrane show two main events of crustal growth (3.0–2.6 and 2.3–1.6 Ga). The crystallization ages on zircon ranges between 3.1 and 0.57 Ga, which is evidence for long-lived crustal reworking. The age for cratonization is still uncertain. In the Taquarembó Block, which is considered the prolongation of the Nico Pérez Terrane in southern Brazil, a similar scenario can be observed. These differences together with contrasting geophysical signatures support the redefinition of the Río de la Plata Craton comprising only the Piedra Alta Terrane and the Tandilia Belt. The Sarandí del Yí Shear Zone is regarded as the eastern margin of this Craton.

Description: The volcaniclastic Tepoztlán Formation (TF) represents an important rock record to unravel the early evolution of the Transmexican Volcanic Belt (TMVB). Here, a depositional model together with a chronostratigraphy of this Formation is presented, based on detailed field observations together with new geochronological, paleomagnetic, and petrological data. The TF consists predominantly of deposits from pyroclastic density currents and extensive epiclastic products such as tuffaceous sandstones, conglomerates and breccias, originating from fluvial and mass flow processes, respectively. Within these sediments fall deposits and lavas are sparsely intercalated. The clastic material is almost exclusively of volcanic origin, ranging in composition from andesite to rhyolite. Thick gravity-driven deposits and large-scale alluvial fan environments document the buildup of steep volcanic edifices. K-Ar and Ar-Ar dates, in addition to eight magnetostratigraphic sections and lithological correlations served to construct a chronostratigraphy for the entire Tepoztlán Formation. Correlation of the 577 m composite magnetostratigraphic section with the Cande and Kent (1995) Geomagnetic Polarity Time Scale (GPTS) suggests that this section represents the time intervall 22.8–18.8 Ma (6Bn.1n-5Er; Aquitanian-Burdigalian, Lower Miocene). This correlation implies a deposition of the TF predating the extensive effusive activity in the TMVB at 12 Ma and is therefore interpreted to represent its initial phase with predominantly explosive activity. Additionally, three subdivisions of the TF were established, according to the dominant mode of deposition: (1) the fluvial dominated Malinalco Member (22.8–22.2 Ma), (2) the volcanic dominated San Andrés Member (22.2–21.3 Ma) and (3) the mass flow dominated Tepozteco Member (21.3–18.8 Ma).

Description: The Sierra Ballena Shear Zone (SBSZ) is part of a high-strain transcurrent system that divides the Neoproterozoic Dom Feliciano Belt of South America into two different domains. The basement on both sides of the SBSZ shows a deformation stage preceding that of the transcurrent deformation recognized as a high temperature mylonitic foliation associated with migmatization. Grain boundary migration and fluid-assisted grain boundary diffusion enhanced by partial melting were the main deformation mechanisms associated with this foliation. Age estimate of this episode is 〉658 Ma. The second stage corresponds to the start of transpressional deformation and the nucleation and development of the SBSZ. During this stage, pure shear dominates the deformation, and is characterized by the development of conjugate dextral and sinistral shear zones and the emplacement of syntectonic granites. This event dates to 658–600 Ma based on the age of these intrusions. The third stage was a second transpressional event at about 586 to 〈560 Ma that was associated with the emplacement of porphyry dikes and granites that show evidence of flattening. Deformation in the SBSZ took place, during the late stages, under regional low-grade conditions, as indicated by the metamorphic paragenesis in the supracrustals of the country rocks. Granitic mylonites show plastic deformation of quartz and brittle behavior of feldspar. A transition from magmatic to solid-state microstructures is also frequently observed in syntectonic granites. Mylonitic porphyries and quartz mylonites resulted from the deformation of alkaline porphyries and quartz veins emplaced in the shear zone. Quartz veins reflect the release of silica associated with the breakdown of feldspar to white mica during the evolution of the granitic mylonites to phyllonites, which resulted in shear zone weakening. Quartz microstructures characteristic of the transition between regime 2 and regime 3, grain boundary migration and incipient recrystallization in feldspar indicate deformation under lower amphibolite to upper greenschist conditions (550–400°C). On the other hand, the mylonitic porphyries display evidence of feldspar recrystallization suggesting magmatic or high-T solid-state deformation during cooling of the dikes.

Description: Movement within the Earth’s upper crust is commonly accommodated by faults or shear zones, ranging in scale from micro-displacements to regional tectonic lineaments. Since faults are active on different time scales and can be repeatedly reactivated, their displacement chronology is difficult to reconstruct. This study represents a multi-geochronological approach to unravel the evolution of an intracontinental fault zone locality along the Danube Fault, central Europe. At the investigated fault locality, ancient motion has produced a cataclastic deformation zone in which the cataclastic material was subjected to hydrothermal alteration and K-feldspar was almost completely replaced by illite and other phyllosilicates. Five different geochronological techniques (zircon Pb-evaporation, K–Ar and Rb–Sr illite, apatite fission track and fluorite (U-Th)/He) have been applied to explore the temporal fault activity. The upper time limit for initiation of faulting is constrained by the crystallization age of the primary rock type (known as “Kristallgranit”) at 325 ± 7 Ma, whereas the K–Ar and Rb–Sr ages of two illite fractions 〈2 μm (266–255 Ma) are interpreted to date fluid infiltration events during the final stage of the cataclastic deformation period. During this time, the “Kristallgranit” was already at or near the Earth’s surface as indicated by the sedimentary record and thermal modelling results of apatite fission track data. (U–Th)/He thermochronology of two single fluorite grains from a fluorite–quartz vein within the fault zone yield Cretaceous ages that clearly postdate their Late-Variscan mineralization age. We propose that later reactivation of the fault caused loss of helium in the fluorites. This assertion is supported by geological evidence, i.e. offsets of Jurassic and Cretaceous sediments along the fault and apatite fission track thermal modelling results are consistent with the prevalence of elevated temperatures (50–80°C) in the fault zone during the Cretaceous.

Description: The application of the SHRIMP U/Pb dating technique to zircon and monazite of different rock types of the Sierras de Córdoba provides an important insight into the metamorphic history of the basement domains. Additional constraints on the Pampean metamorphic episode were gained by Pb/Pb stepwise leaching (PbSL) experiments on two titanite and garnet separates. Results indicate that the metamorphic history recorded by Crd-free gneisses (M2) started in the latest Neoproterozoic/earliest Cambrian (553 and 543 Ma) followed by the M4 metamorphism at ~530 Ma that is documented in the diatexites. Zircon ages of 492 Ma in the San Carlos Massif correlate partly with rather low Th/U ratios (〈0.1) suggesting their growth by metamorphic fluids. This age is even younger than the PbSL titanite ages of 506 Ma. It is suggested that the fluid alteration relates to the beginning of the Famatinien metamorphic cycle in the neighbouring Sierra de San Luis and has not affected the titanite ages. The PTt evolution can be correlated with the plate tectonic processes responsible for the formation of the Pampean orogene, i.e., the accretion of the Pampean basement to the Río de La Plata craton (M2) and the later collision of the Western Pampean basement with the Pampean basement.

Description: Indicator kriging (IK) is a spatial interpolation technique aimed at estimating the conditional cumulative distribution function (ccdf) of a variable at an unsampled location. Obtained results form a discrete approximation to this ccdf, and its corresponding discrete probability density function (cpdf) should be a vector, where each component gives the probability of an occurrence of a class. Therefore, this vector must have positive components summing up to one, like in a composition in the simplex. This suggests a simplicial approach to IK, based on the algebraic-geometric structure of this sample space: simplicial IK actually works with log-odds. Interpolated log-odds can afterwards be easily re-expressed as the desired cpdf or ccdf. An alternative but equivalent approach may also be based on log-likelihoods. Both versions of the method avoid by construction all conventional IK standard drawbacks: estimates are always within the (0,1) interval and present no order-relation problems (either with kriging or co-kriging). Even the modeling of indicator structural functions is clarified.

Description: A complete theoretical presentation of the Continuum-mechanical, Anisotropic Flow model, based on an anisotropic Flow Enhancement factor (CAFFE model) is given. The CAFFE model is an application of the theory of mixtures with continuous diversity for the case of large polar ice masses in which induced anisotropy occurs. The anisotropic response of the polycrystalline ice is described by a generalization of Glen’s flow law, based on a scalar anisotropic enhancement factor. The enhancement factor depends on the orientation mass density, which is closely related to the orientation distribution function and describes the distribution of grain orientations (fabric). Fabric evolution is governed by the orientation mass balance, which depends on four distinct effects, interpreted as local rigid body rotation, grain rotation, rotation recrystallization (polygonization) and grain boundary migration (migration recrystallization), respectively. It is proven that the flow law of the CAFFE model is truly anisotropic despite the collinearity between the stress deviator and stretching tensors.

Description: New 40Ar/39Ar and published 14C ages constrain voluminous mafic volcanism of the Kamchatka back-arc to Miocene (3–6 Ma) and Late Pleistocene to Holocene (〈1 Ma) times. Trace elements and isotopic compositions show that older rocks derived from a depleted mantle through subduction fluid-flux melting (〉20%). Younger rocks form in a back arc by lower melting degrees involving enriched mantle components. The arc front and Central Kamchatka Depression are also underlain by plateau lavas and shield volcanoes of Late Pleistocene age. The focus of these voluminous eruptions thus migrated in time and may be the result of a high fluid flux in a setting where the Emperor seamount subducts and the slab steepens during rollback during terrain accretions. The northern termination of Holocene volcanism locates the edge of the subducting Pacific plate below Kamchatka, a “slab-edge-effect” is not observed in the back arc region.

Description: Aspidochirote holothurian ossicles were discovered in Upper Ordovician-aged Öjlemyr cherts from Gotland, Sweden. The well-preserved material allows definitive assignment to the family Synallactidae, a deep-sea sea cucumber group that is distributed worldwide today. The new taxon Tribrachiodemas ordovicicus gen. et sp. nov. is described, representing the oldest member of the Aspidochirotida. The further fossil record of Synallactidae and evolutionary implications are also discussed.

Description: The configurational heat capacity, shear modulus and shear viscosity of a series of Na2O–Fe2O3–Al2O3–SiO2 melts have been determined as a function of composition. A change in composition dependence of each of the physical properties is observed as Na2O/(Na2O + Al2O3) is decreased, and the peralkaline melts become peraluminous and a new charge-balanced Al-structure appears in the melts. Of special interest are the frequency dependent (1 mHz–1 Hz) measurements of the shear modulus. These forced oscillation measurements determine the lifetimes of Si–O bonds and Na–O bonds in the melt. The lifetime of the Al–O bonds could not, however, be resolved from the mechanical spectrum. Therefore, it appears that the lifetime of Al–O bonds in these melts is similar to that of Si–O bonds with the Al–O relaxation peak being subsumed by the Si–O relaxation peak. The appearance of a new Al-structure in the peraluminous melts also cannot be resolved from the mechanical spectra, although a change in elastic shear modulus is determined as a function of composition. The structural shear-relaxation time of some of these melts is not that which is predicted by the Maxwell equation, but up to 1.5 orders of magnitude faster. Although the configurational heat capacity, density and shear modulus of the melts show a change in trend as a function of composition at the boundary between peralkaline and peraluminous, the deviation in relaxation time from the Maxwell equation occurs in the peralkaline regime. The measured relaxation times for both the very peralkaline melts and the peraluminous melts are identical with the calculated Maxwell relaxation time. As the Maxwell equation was created to describe the timescale of flow of a mono-structure material, a deviation from the prediction would indicate that the structure of the melt is too complex to be described by this simple flow equation. One possibility is that Al-rich channels form and then disappear with decreasing Si/Al, and that the flow is dominated by the lifetime of Si–O bonds in the Al-poor peralkaline melts, and by the lifetime of Al–O bonds in the relatively Si-poor peralkaline and peraluminous melts with a complex flow mechanism occurring in the mid-compositions. This anomalous deviation from the calculated relaxation time appears to be independent of the change in structure expected to occur at the peralkaline/peraluminous boundary due to the lack of charge-balancing cations for the Al-tetrahedra.

Description: It is well-known that sediment composition strongly depends on grain size. A number of studies have tried to quantify this relationship focusing on the sand fraction, but only very limited data exists covering wider grain size ranges. Geologists have a clear conceptual model of the relation between grain size and sediment petrograpic composition, typically displayed in evolution diagrams. We chose a classical model covering grain sizes from fine gravel to clay, and distinguishing five types of grains (rock fragments, poly- and mono crystalline quartz, feldspar and mica/clay). A compositional linear process is fitted here to a digitized version of this model, by (i) applying classical regression to the set of all pairwise log-ratios of the 5-part composition against grain size, and (ii) looking for the compositions that best approximate the set of estimated parameters, one acting as slope and one as intercept. The method is useful even in the presence of several missing values. The linear fit suggests that the relative influence of the processes controlling the relationship between grain size and sediment composition is constant along most of the grain size spectrum.