Molecular composition of the bottom sediments in the Laptev sea outer shelf

Lead Author Elena, Panova
Institution Contact Tomsk, Lenina 30 Tomsk Polytechnic University
Co-Authors Ivan V. Goncharov, Tomsk Polytechnic University, Russia Alexey Ruban, Tomsk Polytechnic University, Russia Andrey Grinko, Tomsk Polytechnic University, Russia Igor Semiletov, Tomsk Polytechnic University, Russia
Theme Theme 1: Vulnerability of Arctic Environments
Session Name 1.1 Climate Change and Environmental Management in the Arctic
Presentation Type Poster
Abstract text The ongoing climate change is apparently manifested in the Arctic region. Permafrost extended there is a huge reservoir of preserved organic matter (OM). In recent years, there is a growing interest to the submarine permafrost containing orders of magnitude greater OM pool than the OM pool of ground permafrost. Therefore, the involvement of submarine permafrost OM pool and coastal ice complex into the modern carbon cycle plays an important role in biogeochemical processes and sedimentation in the Eastern Arctic seas (EAS). The bottom sediments are the main source of methane in EAS, while the rates of methane (CH4) emission are determined by the degree of submarine permafrost degradation and the involvement of OM deep sources, including hydrates and free gas. To understand the transport and OM transformation processes in the land-sea system, including the massive methane emissions from EAS shelf into the water column (and then into the atmosphere), a new approach based on an understanding of the OM nature using its molecular composition studies is required. In that context the question related to the bottom sediments of the Laptev Sea is still poorly known.
This work is aimed at identifying of the biomarkers complex - molecular "fingerprints" of the source organic matter - in the MBA regions characterized by a massive methane release, and outside the seeps (background area), in the areas that are exposed to a coastal erosion and beyond them as well. A performed multi-component OM analysis allows to allocate some typical geochemical features in the distribution of the OM sediments molecular composition on the outer shelf of the Laptev Sea.