ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Publication Date: 2013-10-17
    Description: New sediment cores were recovered from two sites in the central part of Lake Iznik with the overall aim of reconstructing past environmental conditions of the Marmara region. The composite profile presented here, IZN09/LC2&LC3, encompasses the late Pleistocene to Holocene transition (c. 36 ka cal BP) which is the longest lacustrine record in this region obtained to date. A lithostratigraphical and geochronological framework builds the basis to establish a composite section for first inferences on the paleo Lake Iznik. The recovered sedimentary record was divided into five stratigraphic units which can be correlated between the different coring locations. The proposed age-depth model is based on eleven 14C dates (eight radiocarbon-dated levels) and two tephra layers, supported by three OSL ages. The modeled age distribution of the Ca/Ti ratio and magnetic susceptibility express variations in the carbonate accumulation in balance with clastic sediment input. Starting from the end of MIS 3 with high clastic input, Lake Iznik passed through a low lake-level during the Last Glacial Maximum (LGM), delineated by a sublitoral sedimentary facies, and reduced sedimentation rates. After c. 18 ka cal BP, the onset of primary carbonate deposition might be linked to meltwater inflow into the lake as well as onset of lake productivity. From this time onward, there is a gradual increase in carbonate accumulation punctuated by the occurrence of an iron-sulfidic layer which coincides with the Younger Dryas event. At the early Holocene, the lake presents a minimum level as reflected by the maximum carbonate production, followed by a lake level rise at c. 9 ka cal BP which reached a level similar to the modern situation.
    Type: http://purl.org/escidoc/metadata/ves/publication-types/article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    facet.materialart.
    Unknown
    In:  Geophysical Research Abstracts, Vol. 6, 00846 ; Year: 2004
    Publication Date: 2013-10-16
    Type: http://purl.org/eprint/type/ConferencePaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Publication Date: 2017-02-20
    Type: http://purl.org/escidoc/metadata/ves/publication-types/article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Publication Date: 2018-08-22
    Type: http://purl.org/escidoc/metadata/ves/publication-types/article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    facet.materialart.
    Unknown
    In:  25th International Meeting on Organic Geochemistry - IMOG (Interlaken, Switzerland 2011) ; Year: 2011
    Publication Date: 2013-10-17
    Type: http://purl.org/eprint/type/ConferencePaper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    ISSN: 1432-1157
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences
    Notes: Abstract  The Gulf of Saros is an Upper Miocene transtensional basin in NW Anatolia, formed by the interaction between the North Anatolian Fault and the N-S extensional tectonic régime of the Aegean. The present configuration of the basin evolved mainly during the Plio-Quaternary under the increased activity of the North Anatolian Fault. During the late Miocene-late Quaternary, no sedimentation took place on the shelves. After this long hiatus, an important change in tectonic style about 0.2 Ma BP allowed sedimentation to resume in the gulf.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Publication Date: 2014-10-07
    Description: In this paper we provide an overview of new knowledge on oxygen depletion (hypoxia) and related phenomena in aquatic systems resulting from the EU-FP7 project HYPOX (“In situ monitoring of oxygen depletion in hypoxic ecosystems of coastal and open seas, and landlocked water bodies”, www.hypox.net). In view of the anticipated oxygen loss in aquatic systems due to eutrophication and climate change, HYPOX was set up to improve capacities to monitor hypoxia as well as to understand its causes and consequences. Temporal dynamics and spatial patterns of hypoxia were analyzed in field studies in various aquatic environments, including the Baltic Sea, the Black Sea, Scottish and Scandinavian fjords, Ionian Sea lagoons and embayments, and Swiss lakes. Examples of episodic and rapid (hours) occurrences of hypoxia, as well as seasonal changes in bottom-water oxygenation in stratified systems, are discussed. Geologically driven hypoxia caused by gas seepage is demonstrated. Using novel technologies, temporal and spatial patterns of watercolumn oxygenation, from basin-scale seasonal patterns to meter-scale sub-micromolar oxygen distributions, were resolved. Existing multidecadal monitoring data were used to demonstrate the imprint of climate change and eutrophication on long-term oxygen distributions. Organic and inorganic proxies were used to extend investigations on past oxygen conditions to centennial and even longer timescales that cannot be resolved by monitoring. The effects of hypoxia on faunal communities and biogeochemical processes were also addressed in the project. An investigation of benthic fauna is presented as an example of hypoxia-devastated benthic communities that slowly recover upon a reduction in eutrophication in a system where naturally occurring hypoxia overlaps with anthropogenic hypoxia. Biogeochemical investigations reveal that oxygen intrusions have a strong effect on the microbially mediated redox cycling of elements. Observations and modeling studies of the sediments demonstrate the effect of seasonally changing oxygen conditions on benthic mineralization pathways and fluxes. Data quality and access are crucial in hypoxia research. Technical issues are therefore also addressed, including the availability of suitable sensor technology to resolve the gradual changes in bottom-water oxygen in marine systems that can be expected as a result of climate change. Using cabled observatories as examples, we show how the benefit of continuous oxygen monitoring can be maximized by adopting proper quality control. Finally, we discuss strategies for state-of-the-art data archiving and dissemination in compliance with global standards, and how ocean observations can contribute to global earth observation attempts.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , NonPeerReviewed
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Publication Date: 2019-07-16
    Repository Name: EPIC Alfred Wegener Institut
    Type: Conference , NonPeerReviewed
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Mineralium deposita 22 (1987), S. 163-171 
    ISSN: 1432-1866
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences
    Notes: Abstract The Pancarli Ni-Cu mineralization is located in the metamorphic sequence of the Bitlis massif consisting of biotite gneiss, quartz-feldspar gneiss, amphibolite, and metagranitic rocks. The rocks are probably Precambrian in age and have been affected by regional amphibolite-facies metamorphism and by a later cataclasis. There is also evidence of an earlier eclogite-facies metamorphism. The Ni-Cu mineralization occurs as massive sulfide lenses aligned parallel to the penetrative foliation along various levels. The lenses are up to 3 m in length and 2 m in width. The host rock in the immediate vicinity of the orebodies is generally quartz-feldspar gneiss or more rarely quartz-feldspar gneiss and amphibolite. The mineral paragenesis of the ore consisting of pyrrhotite, pentlandite, and chalcopyrite and the low As and Co contents of the ore indicate an orhomagmatic origin of the mineraliza tion. The textures and chemistry of the spinel minerals in the Pancarli deposit together with Cu/(Cu+Ni) ratio of 0.29 of the ore suggest that the mineralization is genetically related to a basic magma. The only mafic rocks in the area are amphibolites that are characterized by a tholeiitic basaltic chemical composition. However, no imprignation and network ores are present in any of the amphibolite bodies. A model based on the segregation of a sulfide melt fraction from a basaltic magma in a magma chamber has been proposed. The subsequent and independent intrusions of the two fractions into the country rocks account for the absence of the impregnation and network ores in the amphibolites, and explain the similarities in geologic setting of the ore and amphibolites as well as their observed field relationships. Structural and textural features of the ores indicate that they have been subjected to regional metamorphism and the later cataclastic deformation that affected the country rocks. The author believes that the ores probably formed during the Pan-African orogenic development of the Bitlis massif in Late Precambrian time. In their present state, the Pancarli ores exhibit varying degrees of weathering with supergene assemblages.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    ISSN: 1432-1866
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences
    Notes: Abstract Kuroko-type massive sulfide deposits of the Eastern Black Sea province of Turkey are related to the Upper Cretaceous felsic lavas and pyroclastic rocks, and associated with clay and carbonate alteration zones in the footwall and hangingwall lithologies. A complete upward-vertical section of a typical orebody consists of a stringer-disseminated sulfide zone composed mainly of pyrite and chalcopyrite; a massive pyrite zone; a massive yellow ore consisting mainly of chalcopyrite and pyrite; a black ore made up mainly of galena and sphalerite with minor amounts of chalcopyrite, bornite, pyrite and various sulfosalts; and a barite zone. Most of the deposits in the province are associated with gypsum in the footwall or hangingwall. The paragenetic sequence in the massive ore is pyrite, sphalerite, chalcopyrite, bornite, galena and various sulfosalts, with some overlap between the mineral phases. Massive, stringer and disseminated sulfides from eight kuroko-type VMS deposits of the Eastern Black Sea province have a δ 34S range of 0–7 per mil, consistent with the δ 34S range of felsic igneous rocks. Sulfides in the massive ore at Madenköy (4.3–6.1 per mil) differ isotopically from sulfides in the stringer zone (6.3–7.2 per mil) suggesting a slightly increased input of H2S derived from marine sulfate with time. Barite and coarse-grained gypsum have a δ 34S range of 17.7–21.5 per mil, a few per mil higher than the δ 34S value of contemporaneous seawater sulfate. The deposits may, therefore, have formed in restricted basins in which bacterial reduction of sulfate was taking place. Fine-grained, disseminated gypsum at Kutlular and Tunca has δ 34S values (2.6–6.1 per mil) overlapping those of ore sulfides, indicating sulfide oxidation during waning stages of hydrothermal activity.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...