Seismic characteristics of natural gas hydrate in Muli area, Tianjun County, Qinghai Province

Natural gas hydrate is a new potential energy source distributed widely in epicontinental seabed sediments and continental permafrost. Physical samples of natural gas hydrate were collected for the first time by drilling in the permafrost region of the Qilian Mountain in 2008. An experimental study of the seismic reflection method in Muli area was carried out for the detection of natural gas hydrate in 2010. Based on a comprehensive analysis and interpretation of seismic, well log and geological data, the authors consider preliminarily that reflections formed by natural gas hydrate media along the seismic profile possess characteristics of low velocity and low amplitude as well as high frequency, and that the distribution of natural gas hydrate is associated with the deep fault zone. As for the formation mechanism of gas resources, it is held that the gas moves up along the deep fault and is enriched and closed by the permafrost, and the gas hydrate deposits are formed under the suitable temperature-pressure conditions.