The Younger Dryas (YD) is recognized as a cool period that began and ended abruptly during a time of general warming at the end of the last glacial. New multi-proxy data from a sediment gravity core from Storfjordrenna (western Barents Sea, 253 m water depth) reveals that the onset of the YD occurred as a single short-lived dramatic environment deterioration, whereas the subsequent warming was ...

Neoproterozoic metasedimentary rocks in the foreland domains of the Kaoko–Dom Feliciano–Gariep orogenic system record sedimentation from the breakup of Rodinia to the amalgamation of Gondwana, and thus provide ideal subjects for investigation of the mutual pre-orogenic positions of rifted margins of the African and South American cratonic blocks. U–Pb isotopic dating of zircon in the Brusque Complex ...

The Palaeoproterozoic greenstone belts of Fennoscandia are metamorphosed and deformed volcanic and sedimentary rocks that formed in basins with a high base-metal ore potential. One of these, the Repparfjord Tectonic Window (RTW), is exposed in the Caledonides of northern Norway and contains several sediment-hosted Cu deposits including Nussir and Ulveryggen. The RTW is composed of mafic metavolcanic ...

The last deglaciation, 20,000–10,000 years ago, was a period of global warming and rapidly shrinking ice sheets. It was also climatically unstable and retreats were interrupted by re-advances. Retreat rates and timing relative to climatic changes have therefore been difficult to establish. We here study a suite of 12 marine sediment cores from Storfjorden and Storfjorden Trough, Svalbard. The purpose ...

The presence of a grounded Greenland Ice Sheet on the northeastern part of the Greenland continental shelf during the Last Glacial Maximum is supported by new swath bathymetry and high-resolution seismic data, supplemented with multi-proxy analyses of sediment gravity cores from Store Koldewey Trough. Subglacial till fills the trough, with an overlying drape of maximum 2.5 m thick glacier-proximal ...

In marine rift basins, deep-water clastics (>200 m) in the hanging wall of rift- or basin-bounding fault systems are commonly juxtaposed against crystalline “basement” rocks in the footwall. A distinct feature of such fault systems is therefore the juxtaposition of relatively highly permeable, unconsolidated sediments against relatively low-permeable basement rocks. Due to limited surface exposure ...

Syn-kinematic mineral reactions play an important role for the mechanical properties of polymineralic rocks. Mineral reactions (i.e., nucleation of new phases) may lead to grain size reduction, producing fine-grained polymineralic mixtures, which have a strongly reduced viscosity because of the activation of grain-size-sensitive deformation processes. In order to study the effect of deformation–reaction ...

The focus of this thesis is structural analysis of the Billefjorden Fault Zone astride Billefjorden and Sassenfjorden in Spitsbergen, with the use of seismic interpretation combined/aided by geological and bathymetric maps, field observations and well data. The aim is to describe structures and the tectonic development of the study area. The focus is on large tectonic events from Devonian to ...

The onset and evolution of the middle to late Cenozoic “icehouse” world was influenced by the development of the global ocean circulation linking the Norwegian–Greenland Sea-Arctic Ocean to the Atlantic Ocean. The evolution of the early Neogene to early Quaternary Bjørnøyrenna Drift, located at the SW Barents Sea continental margin, shed new light on this important hydrological event. By analyzing ...

We investigate the uppermost 60 cm of sediment in active pockmarks of a deep-water methane seep site from Vestnesa Ridge offshore NW Svalbard. Using video guided core sampling with a remotely operated vehicle we collected push cores directly from bacterial mats within two active pockmarks, Lunde and Lomvi. Pore water analyses show very shallow sulphate methane transition zones and transport-reaction ...