“…In spite of a significant interest paid to studying greenhouse gas balance in the atmosphere, the estimates of the main sources of one of the most important greenhouse gases, methane, are rather uncertain [3,16]. In accordance with [12,14], the contribution of methane releases from oil and gas production and transportation is estimated at~40-70 billion m 3 per year, or about 10-20% of the global anthropogenic methane emission.…”