Assessments of resources of gas hydrates and characteristics of hydrate reservoirs of the seas of Russia

The article presents the results of a quantitative assessment of the predicted resources of subaqueous gas hydrates within the exclusive economic zone of Russia and Lake Baikal as of 01.01.2024 at three different levels – global, regional and local. The assessments were carried out using the specific density method based on numerical modeling of the gas hydrate stability zone, its mapping and identification of gas hydrates based on the interpretation of a large volume of digital seismic CDP data and the results of marine sediment sampling. A total of 203 gas hydrate accumulations were identified and taken into account in the exclusive economic zone of the Russian Federation within the Barents, Laptev, East Siberian, Bering, Okhotsk, Japan and Black seas. The total volume of gas hydrate reservoirs in the Russian seas and Lake Baikal is estimated at 520 trillion km 3 , where the share of methane in gas hydrates averages just over 10% and the estimated global gas hydrate resource value is more than 147 trillion m 3 . Gas hydrate reservoirs in the seas are confined to the interval of subbottom depths from the seabed to 1250 m in the stratigraphic interval from the Holocene to the Oligocene. The largest number of accumulations are confined to the Pliocene sediments. Gas resources in gas hydrate accumulations vary from 0.1 to 6830 billion m 3 , corresponding in terms of resource size to traditional gas fields from very small (with reserves of less than 1 billion m3 ) to unique (with reserves of more than 300 billion m 3 ).