Scientists have identified the source of methane in the waters of the Laptev Sea: the concentration of the substance is associated with the destabilization of the permafrost at their bottom and the release of ancient gas reserves.
We carried out isotopic measurements, which clearly indicated that the concentration of methane in the waters of the Laptev Sea is increasing mainly as a result of the release of ancient reserves of this gas, hidden under the permafrost layer at the bottom of the ocean. This indicates the possible beginning of the disintegration of this soil layer and the existence of a large reservoir of gas, which can be abruptly ejected into the atmosphere.
The discovery of such emissions forced scientists to debate where these emissions come from and whether they are all related to the destabilization of ancient permafrost and clathrate deposits.
The authors of the work believe that the release of methane indicates a possible disintegration of the soil layer. There may be a volumetric gas reservoir under the permafrost. With the destruction of the soil layer, all the methane will be abruptly released into the atmosphere. Not so long ago, similar events took place at the bottom of the Barents Sea.
The group of researchers analyzed the isotopic ratios of carbon and three different forms of dissolved methane in the waters of the East Siberian Arctic shelf: they serve as indicators of conditions in the source of gas formation and subsequent diagenetic processes – the transformation of loose sediments into sedimentary rocks.
These measurements showed that, in all cases, the concentration of carbon-14 in methane molecules was close to zero in the vicinity of the alleged gas sources at the bottom of the Laptev Sea and gradually increased with distance from them.
Further research will lead to more accurate conclusions.