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The Münchberg Massif in northeastern Bavaria, Germany is an allochthonous metamorphic nappe complex within the Saxothuringian Zone of the Variscan orogen. From top to bottom it consists of four major units: Hangend-Serie, Liegend-Serie, Randamphibolit-Serie and Prasinit-Phyllit-Serie, which show an inverted metamorphic gradient of eclogite- to amphibolite-facies (top) to greenschist-facies (bottom) and are separated from each other by thrust faults. New geochemical and U-Pb zircon data indicate that the four units host metasedimentary and meta-igneous rocks, which were formed at different time and in distinct geotectonic settings during the evolution of the Saxothuringian terrane between 550 and 370 Ma. Mafic and felsic protoliths of the Hangend-Serie result from a bimodal magmatism in an evolved oceanic to continental magmatic arc setting at about 550 Ma. These rocks represent relics of the Cadomian magmatic arc, which formed a cordillera at the northern margin of Gondwana during the Neoproterozoic. The Liegend-Serie hosts slivers of granitic orthogneisses, emplaced during magmatic events at c. 505 and 480 Ma, and Early Palaeozoic paragneisses, with our samples deposited at ≤ 483 Ma. Ortho- and paragneisses were affected by an amphibolite-facies metamorphic overprint at c. 380 Ma. Granite emplacement and sediment deposition can be related to the separation of the Avalonia microterrane from the northern Gondwana margin. Amphibolite protoliths of the Randamphibolit-Serie emplaced at c. 400 Ma. They show N-MORB to E-MORB signatures, pointing to their formation along an oceanic spreading centre within the Rheic ocean. Mafic igneous rocks in the Prasinit-Phyllit-Serie emplaced at nearly the same time (407–401 Ma), but their calc-alkaline to tholeiitic character rather suggests formation in an intra-oceanic island arc/back arc system. This convergent margin lasted for about 30 Ma until the Late Devonian, as is suggested by a maximum deposition age of 371 Ma of associated phyllites, and by metamorphic Ar-Ar ages of 374–368 Ma. The timing of the different magmatic and sedimentary events in the Münchberg Massif and their plate tectonic settings are similar to those estimated for other Variscan nappe complexes throughout Europe, comprising the French Massif Central and NW Spain. This similarity indicates that the Münchberg Massif forms part of an European-wide suture zone, along which rock units of different origin were assembled in a complex way during the Variscan Orogeny. [ABSTRACT FROM AUTHOR]

Scientific Drilling through the ice shelfs of Antarctica is essential to understand ice sheet dynamics, the transition from greenhouse to ice-house in the Eocene to Oligocene, and the breakup of the Gondwana continent. The Alfred-Wegener-Institute, Helmholtz Centre for Polar and Marine Research (AWI) and the Federal Institute for Geosciences and Natural Resources (BGR) jointly conduct a pre-site survey in order to identify potential drilling locations in the vicinity of the German Neumayer III station. There, a sequence of >1000m thick sediments of potentially Late Mesozoic to Quaternary age has been identified on top of the presumed synor post-rift volcanic Explora Wedge between the ice shelf calving line and some 40 km inland under the Eckström Ice Shelf. During a first survey in the Antarctic season 2016/17 eleven high resolution vibro-seismic profiles with a total length of 285 km were obtained (Kuhn et al. 2018, this volume). Based on this data set and additional profiles recorded during the season 2017/18 several locations for sampling of surface sediment were identified. Sampling of the seafloor by retrieving short cores of the oldest and youngest sediments through Hot Water Drill holes was carried out in late December 2017 to late January 2018. As next steps, AWI and BGR agreed to finance a further campaign for additional sampling and oceanographic pre-site studies to be carried out in the following Antarctic season 2018/19. Under the LASCAR and PAIS umbrella we will re-establish a D-ANDRILL group to coordinate these related national projects. An international workshop is then planned to bring together researchers with interest in scientific drilling and to discuss and develop a drilling proposal. We particularly like to encourage scientists from the German polar research community based at universities and other research institutions to contribute to this project. [ABSTRACT FROM AUTHOR]

During the last seasons and ongoing, pre-site seismic surveys have taken place in the Ekströmisen region of Dronning Maud Land, with the primary goal of building a stratigraphic age framework of the under-ice-shelf sediments. These sediments overlie the Explora Wedge, a syn- or post-rift volcanic deposit. Expected ages range from Late Mesozoic to Quaternary. From new vibroseismic profiles, we selected sites for short core seafloor sampling through Hot Water Drill (HWD) holes of the oldest and of the youngest sediment sequences to confine their age time span. There is further potential for drilling deeper sediment cores with the support of international partner. Deep drilling should recover the sediments overlying the Explora Escarpment, in order to discover the nature of the Explora Wedge. We expect the overlying sediment sequences to reveal the history of polar amplification and climate changes in this part of Antarctica, the build-up of the East Antarctic Ice Sheet during past warmer climates, and its Cenozoic and future variability. Having HWD holes through the shelf ice and sampling the sea floor will provide the unique opportunity for further piggy back experiments consisting of multi-disciplinary nature. Experiments and measuring setup for oceanography, sea and ice shelf physics, geophysics, geology, hydrography, biogeochemistry could be planned to characterise the ocean-icesediment interactions, processes and ecosystem observations. The deployment of Autonomous Underwater Vehicles (AUV) either through a HWD hole or launched from a ship or from the fast ice with the power to operate and measure in the sub-ice shelf cavern may become reality during future campaigns. [ABSTRACT FROM AUTHOR]