ALBERT

Description: All coleoid hatchlings have a special complex of glandular cells situated at the mantle tip, which store a hatching enzyme that is released at the close of embryonic development; it locally dissolves the chorion membrane and any surrounding envelopes, thus producing a hatch opening. In most coleoids the hatchling also uses auxiliary equipment and actions to effectively extract itself from the egg case. This article considers the co-aptation between parental (egg cases) and filial contributions (hatching gland etc) in different coleoid groups.

Description: In many subaerial hydrothermal ore deposits arsenian pyrite is an important host for Au, however, arsenian pyrite is rare on the modern seafloor. During a recent survey for submarine hydrothermal mineralization in the western Woodlark Basin volcanic breccias containing abundant arsenian pyrite were dredged from the flanks of a volcanic seamount in a water depth of 2000 m. This area is particularly interesting because it is located at the transition from continental splitting to oceanic spreading where enhanced heat flow and deep crustal faults may fertilize mineralization. The sulfidic breccia is essentially monomictic and matrix-supported containing altered dacitic clasts. Mineralogical investigation of the breccia reveals silicification and sulfidation as the main alteration types. Quartz occurs in fragments and also constitutes the breccia matrix attesting to silicification as a significant alteration process. Pyrite is the dominant ore mineral with only minor amounts of Fe-oxyhydroxide and goethite. Bulk geochemistry shows a slight enrichment of Au (0.12 ppm) in association with elements such as As-Ag-Hg-Zn-Pb-Sb, key elements indicative of a low sulfidation environment. Three generations of pyrite are recognized on the basis of morphology. Arsenic-free, early framboidal pyrite (py1) is overgrown by arsenian colloform (py2) or massive pyrite (py3) containing up to 3.93 wt% As. Arsenic speciation in the pyrite is in the form of As1- and As3+. The presence of arsenian pyrite in hydrothermal breccias at this seamount indicates the potential for Au mineralization in the area.

Description: The stratigraphic section “Kellwasser-Tal” is the type locality of the Late Devonian Kellwasser Horizons. The locality, which was already badly preserved shortly after its discovery in the middle of the 19 th century by F.A. Roemer, has recently been re-opened and widened. The newly created section ranges from the upper Frasnian to the Lower Carboniferous “Kulm-Kieselschiefer”. Although some parts of the outcrop are highly tectonised it is nonetheless possible to reconstruct the sedimentary sequence. The Kellwasser Horizons, connected to one of the five most severe mass-extinction events in Earth History (Kellwasser Crisis), can now be studied again in detail. Conodonts sampled by O.H. Walliser (Göttingen) in the 1980s as well as new samples were investigated with respect to conodont biostratigraphy and microfacies. The type locality is situated in the European Geopark Harz-Braunschweiger Land-Ostfalen and should be protected as a geosite. Das Profil Kellwasser-Tal (NW-Harz) ist die Typlokalität der oberdevonischen Kellwasser-Horizonte. Die Lokalität, schon bald nach ihrer Entdeckung durch F.A. Roemer Mitte des 19. Jahrhunderts verfallen, ist maschinell erneut freigelegt worden. Es liegt nun ein zusammenhängendes Profil vom höheren Frasnium bis in die Kulm-Kieselschiefer des Unterkarbons vor. Obwohl Teile des Aufschlusses tektonisch sehr stark beansprucht sind, ist die Rekonstruktion der sedimentären Abfolge möglich. Die beiden Kellwasser-Horizonte, zwei isochrone, global nachweisbare Litho-Einheiten (,,Kellwasser-Kalke“), sind wieder gut aufgeschlossen. Sie bezeugen eines der fünf größten Aussterbe-Ereignisse der Erdgeschichte (Kellwasser-Krise). Im Zusammenhang mit den Geländeaktivitäten ist Sammlungsmaterial (Conodontenfaunen, An- und Dünnschliffe) aufgearbeitet worden, so dass der gegenwärtige Bearbeitungsstand der Lokalität dargestellt werden kann. Grundlage der stratigrafischen Bearbeitung waren insbesondere Conodontenproben, welche unter Leitung von O.H. Walliser (Göttingen) in den 1980er Jahren gesammelt wurden. Zusätzliches, in den letzten Jahren entnommenes Material (Conodonten- und sedimentologisch-fazielle Proben) ließ sich mit den Banknummern von Walliser korrelieren. Diese Typlokalität ist Teil des Europäischen Geoparks Harz-Braunschweiger Land-Ostfalen und sollte als Geotop geschützt und erhalten bleiben.

Description: The long-term climate cooling during Campanian - Maastrichtian times is not well understood to date, especially because of the uncertainty introduced by low temporal resolution of biostratigraphy and the pronounced provincialism between tropical and temperate taxa. Two new high-resolution carbon isotope records derived from the boreal shelf-sea section at Lägerdorf-Kronsmoor-Hemmoor, northern Germany and the tropical Pacific at Deep Sea Drilling Project Site 305, Shatsky Rise, reduce these uncertainties. The records can be correlated with an accuracy not achieved by biostratigraphic methods so far. Distinct carbon isotope events in the late Campanian and the early Maastrichtian can be identified at both localities suggesting to represent global carbon cycle perturbations. Especially, the negative carbon isotope excursion in the early Maastrichtian, a pronounced feature of open-ocean records from the Pacific and Southern oceans, is recognized for the first time at a shelf-sea locality related to the North Atlantic Ocean. Furthermore, two short-term positive excursions are identified as superimposed signals to this event. The improved stratigraphy provides the unique opportunity to recognize leads and lags between the carbon cycle and ocean circulation of different marine settings and ecosystems, leading to a better understanding of their causes and effects.

Description: Cyanobacterial community composition was studied along a salinity gradient from the saline Spring Fuliya towards the water column of Lake Kinneret. The samples included a gradient of salinities ranging from 4270 mg Cl L-1 (Saline Spring) to 239 mg Cl L-1 (Lake Kinneret). Denaturing gradient gel electrophoresis (DGGE) and cloning of the 16 S rRNA gene, as well as cloning and sequencing of the psbA gene, were used to characterize cyanobacterial community composition. Despite the differences in salinity, similar cyanobacterial communities were observed in the lake and the saline spring, the only exception being the highest salinity sample (4270 mg Cl L-1). Both, DGGE patterns and results of the clone libraries revealed the dominance of cyanobacteria with colonial Gloeocapsa and unicellular Synechococcus as the closest known cultured relatives, independently of the salinity. These results suggest that cyanobacterial populations inhabiting this freshwater lake and its saline sources can adapt to a wide range of salinities.