This study is focused on mineralogical and chemical characterization of an authigenic carbonate rock (crust) collected at a recently discovered cold seep on the US North Atlantic continental margin. X-ray diffraction (XRD) and scanning electron microscopy (SEM) indicate that the carbonate rock is composed of microcrystalline aragonite cement, white acicular aragonite crystals (AcAr), equant quartz ...

Methane seepage occurs across the western Svalbard margin at water depths ranging from < 300 m, landward from the shelf break, to > 1000 m in regions just a few kilometres from the mid-ocean ridges in the Fram Strait. The mechanisms controlling seepage remain elusive. The Vestnesa sedimentary ridge, located on oceanic crust at a depth of 1000–1700 m, hosts a perennial gas hydrate and associated free ...

Temporal variations in ice sheet flow directly impact the internal structure within ice sheetsthrough englacial deformation. Large-scale changes in the vertical stratigraphy within ice sheets havebeen previously conducted on centennial to millennial timescales; however, intra-annual changes inthe morphology of internal layers have yet to be explored. Over a period of 2 years, we use autonomousphas ...

The Quaternary sedimentary record in the Arctic captures a diverse and evolving range of landscapes reflecting cli-mate changes. Here we study the geological landform assemblage of the Upper Regional Unconformity (URU) in theSW Barents Sea. The aims are (i) to characterize buried geological landforms on a meter-scale resolution, (ii) to un-derstand their link with underlying structures, and (iii) ...

<i>Introduction</i>: As the title of the correspondence by Fossen et al.1 suggests, determining the age of landscape elements of the Earth surface is difficult. We thus welcome the opportunity to clarify our arguments on the contentious themes touched upon by Fredin et al.2 The age of landscapes has been a recurring research topic for the last century. Often, landscape ages can be deduced indirectly ...

The investigation of trough mouth fans (TMFs), important paleoclimatic archives on mid- and high-latitude continental margins, has so far mainly been based on the integration of various types of acoustic data supplemented with short sediments cores. In consequence, sedimentological and chronological data about parts of TMFs deposited prior to the Last Glacial Maximum remains sparse. Here, we re-evaluate ...

Shear experiments were performed in a Griggs-type apparatus at 800 °C and 1.5 GPa, at a strain rate of 2.1 × 10⁻⁵s⁻¹ using different starting materials: (i) Powder (grain size 6–10 μm) of dry Brazil quartz with 0.15 wt% added H₂O, (ii) “dry” Brazil quartz porphyroclasts (grain size ∼100–200 μm), devoid of fluid inclusions embedded in the same fine grained powder, and ...

The Lofoten Ridge is an integral basement horst of the hyperextended continental rift-margin off northern Norway. It is a key area for studying onshore–offshore rift-related faults, and for evaluating tectonic control on landscape development along the North Atlantic margin. This paper combines onshore geomorphological relief/aspect data and fault/fracture analysis with offshore bathymetric and ...

Проанализированы результаты спутникового зондирования с помощью европейского орбитального интерферометра IASI/MetOP-A и алгоритма обработки данных, разработанного в NOAA. Спутниковые измерения для умеренных и высоких широт Северного полушария дают рост скорости концентрации метана от 4–9 ppbv/год (частей на миллиард по объему) в 2010–2013 гг. до 12–17 ppbv/год в 2015–2016 гг. Глобальные оценки на ...

We present ionospheric plasma conditions observed by the EISCAT radars in Tromsø and on Svalbard, covering 68°–81° geomagnetic latitude, during 6–8 September 2017. This is a period when X2.2 and X9.3 X‐ray flares occurred, two interplanetary coronal mass ejections (ICMEs) arrived at the Earth accompanied by enhancements of MeV‐range energetic particle flux in both the solar wind (SEP event) and inner ...