Research project Physical and geothermal properties of Arctic Ocean sediments:

Warming of intermediate waters could trigger the widespread dissociation of marine hydrates on the continental slopes surrounding the Arctic Ocean. The associated release of methane into the water column and atmosphere is an unconstrained source of greenhouse gases, and may play a role in the acidification of Arctic water masses. The physical and geothermal properties of Arctic sediments are primary controls on the thickness of potential gas hydrate bearing sediments (thermal conductivity and geothermal gradient), the quantity of methane trapped within them (porosity) and the rate at which it could be released from the seafloor (permeability). This project was designed to improve our ability to assess the distribution and stability of gas hydrate deposits on the continental slopes of the Arctic by providing quantified assessments of in-situ porosity, permeability, thermal conductivity, and geothermal gradients for sediments along the Eurasian and East Siberian Sea margins of the Arctic Ocean. The project focused largely on the continental slope of the East Siberian Sea, collecting valuable new data from this sector of the Arctic Ocean during the SWERUS-C3 Program (Swedish-Russian-US Arctic Ocean Investigation of Climate-Cryosphere-Carbon Interactions) in 2014.

Figure Caption: Map of the Arctic Ocean illustrating existing terrestrial (green) and marine (yellow) heat flow measurements from the World Heat Flow Databank (accessed in 2016). In this project new data was collected on the East Sibserian shelf and slope (red triangles), and used to constrain the possible extent of the methane hydrae stability zone. Black contour line is the 2000 m isobath. The red line is the cruise track during Leg 1 and 2 of SWERUS-C3. Abbreviations: AR – Alpha Ridge; CAA – Canadian Arctic Archipelago; CB – Canada Basin; GR – Gakkel Ridge; LR – Lomonosov Ridge; MR – Mendeleev Ridge.