In the central Iranian Esfahan-Sirjan and Qom basins sedimentation of the Oligo-/Miocene Qom Formation took place on extensive mixed carbonate-siliciclastic ramps. During this time, both basins were positioned at the Eurasian margin of the Tethyan Seaway, which connected the western and eastern regions of the Tethys Ocean at least until the late Burdigalian. During the so-called Terminal Tethyan Event the Tethyan Seaway was then closed due to the collision of the African/Arabian and Iranian/Eurasian plates. Facies analysis of the sedimentary record of both basins indicates paleoenvironments ranging from terrestrial to open marine settings, including mangrove, restricted inner shelf lagoon, seagrass meadow, reefal, and deeper offshore environments. Recognition of eight depositional sequences and elaboration of an integrated biostratigraphic framework (calcareous nannoplankton, planktic and larger benthic foraminifers, gastropods, and pectinids) allow us to construct a basin-spanning stratigraphy. The assignment of the recognized sea-level lowstands to the Ru 3 to Bur 3 lowstands of the global sea-level curve enables a comparison with time-equivalent sections from the Zagros Basin, which was part of the African/Arabian Plate on the opposing southern margin of the Tethyan Seaway. The so calibrated sections display restrictions of the Tethyan Seaway and interruption of the south Iranian gateways between the Qom Basin and the Proto-Indopacific in relation to ongoing plate collision during the early Burdigalian.

Abstract. Das Quartär der Bodensee-Region besteht aus Schottern frühpleistozäner alpiner Flusssysteme (Deckenschotter) sowie aus glazialen und Schmelzwasser-Ablagerungen der mittel- und spätpleistozänen Eiszeiten. Sie belegen den landschaftlichen Wandel von einer Art Rampe aus Vorbergen hin zur heutigen Topographie mit ineinander greifenden, übertieften Becken, sodass sich eine Art Amphitheater ergibt. Die Deckenschotter als älteste Ablagerungen dokumentieren einerseits die Eintiefung der alpinen Flüsse in diversen Terrassenstufen im Sedimentationsgebiet, andererseits durch deutliche Unterschiede im Geröllspektrum die Vergrößerung des Liefergebiets des sich entwickelnden alpinen Rheins. Der älteste Till kommt vor in Kontakt mit Mindel-Deckenschottern, es gibt jedoch keine Hinweise auf eine glaziale Übertiefung in dieser Zeit. Die meisten glazialen und Schmelzwasser-Ablagerungen werden drei großen Vergletscherungen des Rheingletschers zugeordnet. Diese Vorlandvergletscherungen sind mit drei Generationen glazialer Becken verknüpft. Die ältesten Becken sind zur Donau orientiert, die aus der letzten Vereisung entwässern zum Rhein. Diese Reorientierung bewirkte die hervorragende räumliche Auflösung der Sedimente und Formen. Traditionell wurden die Sedimente in einem chronostratigraphischen System aus glazialen und interglazialen Stufen beschrieben. Unsere Ziele in dieser Arbeit sind, eine Aktualisierung des chronostratigraphischen Systems vorzustellen, das neue, beim geologischen Dienst von Baden-Württemberg angewandte, lithostratigraphische Schema zu erklären und die wichtigsten neuen Einheiten kurz zu beschreiben.

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Over‐deepened basins exist throughout the Alpine realm. Improving our knowledge on these basins is of high social relevance, since these areas are often well‐populated and they possess, for instance, unusual hydrological settings. Nonetheless, geophysical and sedimentological investigations of over‐deepened basins are rare. We analyse the sedimentary succession of such a basin, the Tannwald Basin, through geological interpretation of seismic reflection profiles. The basin is located approximately 60 km north of the European Alps. It was incised into Tertiary molasse sediments by the Rhine Glacier and later filled by glacial, fluvial, and lacustrine deposits of 250 m thickness. The Leibniz Institute for Applied Geophysics acquired a grid of five high‐resolution seismic reflection lines that imaged till the deepest parts of the Tannwald Basin. The seismic profiles, processed to a pre‐stack depth migration level, allow a detailed geological interpretation that is calibrated with the help of a nearby borehole. We determine the structure and the seismic facies of the sediment succession in the basin and presume the following hypothesis of the evolution of the basin: sub‐glacial erosion comprises the excavation of the over‐deepened basin as well as detachment of large fragments of molasse material. These molasse slabs were deposited within the basin in a layer of basal till that graded upwards in water‐lain till and fine‐grained deposits. During the last two glaciations, the basinal structure became buried by till sequences and glacio‐fluvial sediments.

Abstract. A description and classification of the successions of the new scientific core drillings at Heidelberg is presented. Since 2002 drilling and research activities were ongoing in the Heidelberg Basin (HDB), as a mid-continental sedimentary archive within the Upper Rhine Graben (URG), Germany. The HDB is supposed to host one of the longest continuous successions of Quaternary sediments in Europe, due to continuous subsidence of the basin and sediment input from various sources. The HDB is about half-way between the Alpine source area of the Rhine and the North Sea. Here the Quaternary input is least affected by discontinuities due to climate events as alpine glacier meltdown events or periods of low sea level. Reversely, the low influence of climate leads to a larger tectonic control. The sedimentary succession of more than 500 m is considered as primarily controlled by tectonics, but with incorporated climate signals. For classification purposes, sediment provenance, lithofacies-associations, and the ratio of accommodation space and sediment input are used. Some biostratigraphic markers are also available. We suggest a sedimentary scenario where the overall fluvial environment is twice interrupted by lacustrine intervals. The accommodation space varies too: in one period it expands even beyond the eastern boundary fault of the HDB.

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Probabilistic seismic hazard assessments are primarily based on instrumentally recorded and historically documented earthquakes. For the northern part of the European Alpine Arc, slow crustal deformation results in low earthquake recurrence rates and brings up the necessity to extend our perspective beyond the existing earthquake catalog. The overdeepened basin of Lake Constance (Austria, Germany, and Switzerland), located within the North-Alpine Molasse Basin, is investigated as an ideal (neo-) tectonic archive. The lake is surrounded by major tectonic structures and constrained via the North Alpine Front in the South, the Jura fold-and-thrust belt in the West, and the Hegau-Lake Constance Graben System in the North. Several fault zones reach Lake Constance such as the St. Gallen Fault Zone, a reactivated basement-rooted normal fault, active during several phases from the Permo-Carboniferous to the Mesozoic. To extend the catalog of potentially active fault zones, we compiled an extensive 445 km of multi-channel reflection seismic data in 2017, complementing a moderate-size GI-airgun survey from 2016. The two datasets reveal the complete overdeepened Quaternary trough and its sedimentary infill and the upper part of the Miocene Molasse bedrock. They additionally complement existing seismic vintages that investigated the mass-transport deposit chronology and Mesozoic fault structures. The compilation of 2D seismic data allowed investigating the seismic stratigraphy of the Quaternary infill and its underlying bedrock of Lake Constance, shaped by multiple glaciations. The 2D seismic sections revealed 154 fault indications in the Obersee Basin and 39 fault indications in the Untersee Basin. Their interpretative linkage results in 23 and five major fault planes, respectively. One of the major fault planes, traceable to Cenozoic bedrock, is associated with a prominent offset of the lake bottom on the multibeam bathymetric map. Across this area, high-resolution single channel data was acquired and a transect of five short cores was retrieved displaying significant sediment thickness changes across the seismically mapped fault trace with a surface-rupture related turbidite, all indicating repeated activity of a likely seismogenic strike-slip fault with a normal faulting component. We interpret this fault as northward continuation of the St. Gallen Fault Zone, previously described onshore on 3D seismic data.

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