The phase-sensitive radio-echo sounder (pRES) is a powerful new instrument that can measure the depth of internal layers and the glacier bed to millimetre accuracy. We use a stationary 16-antenna pRES array on Store Glacier in West Greenland to measure the three-dimensional orientation of dipping internal reflectors, extending the capabilities of pRES beyond conventional depth sounding. This novel ...

Many Arctic marine-terminating glaciers have undergone rapid retreats in recent decades. Seasonal and year-to-year variations in terminus position act on all tidewater glaciers, but the key controls on those changes vary from region to region. Here, we examined seasonal and decadal changes in termini positions of seven tidewater glaciers in the inner part of Hornsund, the southernmost fjord of ...

A better understanding of past extent and dynamics of the Greenland Ice Sheet (GrIS) is required to provide context for present-day observations, to constrain numerical climate models and to predict future scenarios of ice-sheet response to recent climatic change. The presence of a grounded GrIS on the NE Greenland shelf during the Last Glacial Maximum (LGM) is supported by high-resolution seismic ...

To understand the processes involved in phase mixing during deformation and the resulting changes in rheological behavior, we conducted torsion experiments on samples of iron‐rich olivine plus orthopyroxene. The experiments were conducted at a temperature, T, of 1200°C and a confining pressure, P, of 300 MPa using a gas‐medium deformation apparatus. Samples composed of olivine plus 26% orthopyroxene ...

In order to study the mutual effect of deformation and mineral reactions, we have conducted shear experiments on fine-grained plagioclase-pyroxene assemblages in a Griggs-type solid-medium deformation apparatus. Experiments were performed at a constant shear strain rate of 10⁻⁵ s⁻¹, a confining pressure of 1 GPa and temperatures of 800, 850 and 900 °C. While the peak stress of ...

The Sasa Pb-Zn-Ag deposit belongs to the group of distal base metal skarn deposits. The deposit is located within the Serbo-Macedonian massif, a metamorphosed crystalline terrain of Precambrian to Paleozoic age. The mineralization, hosted by Paleozoic marbles, shows a strong lithological control. It is spatially and temporally associated with the calc-alkaline to shoshonitic post-collisional magmatism ...

Information from former ice sheets may provide important context for understanding the response of today’s ice sheets to forcing mechanisms. Here we present a reconstruction of the last deglaciation of marine sectors of the Eurasian Ice Sheet, emphasising how the retreat of the Norwegian Channel and the Barents Sea ice streams led to separation of the British-Irish and Fennoscandian ice sheets at ...

The dominance of isotropic hummocky cross‐stratification, recording deposition solely by oscillatory flows, in many ancient storm‐dominated shoreface–shelf successions is enigmatic. Based on conventional sedimentological investigations, this study shows that storm deposits in three different and stratigraphically separated siliciclastic sediment wedges within the Lower Cretaceous succession in ...

Methane expulsion from the world ocean floor is a broadly observed phenomenon known to be episodic. Yet the processes that modulate seepage remain elusive. In the Arctic offshore west Svalbard, for instance, seepage at 200–400 m water depth may be explained by ocean temperature‐controlled gas hydrate instabilities at the shelf break, but additional processes are required to explain seepage in ...