Sub-sea Arctic methane and gas hydrate reservoirs are expected to be severely impacted by ocean temperature increase and sea-level rise. Our understanding of the gas emission phenomenon in the Arctic is however partial, especially in deep environments where the access is difficult and hydro-acoustic surveys are sporadic. Here, we report on the first continuous pore-pressure and temperature measurements ...

Despite more than a century of investigation, the relationship between basement rocks throughout the Svalbard Archipelago is still a mystery. Though these rocks display similar geochronological ages, they show significantly different metamorphic grades and structures. Thus far, Svalbard was believed to be composed of three terranes of rocks formed hundreds–thousands of kilometers apart and accreted ...

During expedition MARIA S. MERIAN MSM57/2 to the Svalbard margin offshore Prins Karls Forland, the seafloor drill rig MARUM‐MeBo70 was used to assess the landward termination of the gas hydrate system in water depths between 340 and 446 m. The study region shows abundant seafloor gas vents, clustered at a water depth of ∼400 m. The sedimentary environment within the upper 100 m below seafloor (mbsf) ...

The Caledonian evolution of the low–medium grade Balsfjord Series (Troms, Northern Norway) is characterized by four sets of deformation structures that developed progressively during burial and exhumation from underneath the high-grade Nakkedal and Tromsø nappe complexes. The Balsfjord Series commonly displays top-to-the SSE–SE directed movement during the development of the main metamorphic fabric ...

Fossil benthic foraminifera are used to trace past methane release linked to climate change. However, it is still debated whether isotopic signatures of living foraminifera from methane-charged sediments refect incorporation of methane-derived carbon. A deeper understanding of isotopic signatures of living benthic foraminifera from methane-rich environments will help to improve reconstructions of ...

Displacement rates of mountain slope deformations that can affect entire valley mountain flanks are often measured spatially distributed in‐situ without spatial significance. The spatially explicit measurement and recording of time series of slope deformations is a challenge, as the unstable slopes are often disintegrated into several subdomains, which move with different deformation rates. The ...

The Vestnesa Ridge is a NW-SE trending, ~ 100 km-long, 1–2 km-thick contourite sediment section located in the Arctic Ocean, west of Svalbard, at 79°N. Pockmarks align along the ridge summit at water depths of ~ 1200 m; they are ~ 700 m in diameter and ~ 10 m deep relative to the surrounding seafloor. Observations of methane seepage in this area have been reported since 2008. Here we summarize and ...

Seafloor seepage sites along the Vestnesa Ridge off west-Svalbard have been, for decades, a natural laboratory for the studies of fluid flow and gas hydrate dynamics at passive continental margins. The lack of ground truth evidence for fluid composition and gas hydrate abundance deep in the sediment sequence however prohibits us from further assessing the current model of pockmark evolution from the ...

PalaeoArc (Processes and Palaeo-Environmental Changes in the Arctic: From Past to Present) is an international network research programme, the aim of which is to understand and explain the climatically induced environmental changes in the Arctic that have taken place throughout the Quaternary and continue in the present-day (see http://www.palaeoarc.no/). This network builds on and extends the ...

Anoxic marine sediments contribute a significant amount of dissolved iron (Fe²⁺) to the ocean which is crucial for the global carbon cycle. Here, we investigate iron cycling in four Arctic cold seeps where sediments are anoxic and sulfidic due to the high rates of methane-fueled sulfate reduction. We estimated Fe²⁺ diffusive fluxes towards the oxic sediment layer to be in the ...