Abstract:

The intensive gas hydrate geochemical exploration has been taken in Sanlutian field, Muli, Qinghai. The work area is 10 square kilometers, and sampling density is 16 points per square kilometer, the soil acid-extracted and headspace gas of each point has been analyzed. The explaining of geochemical anomaly focused on the difference of gas hydrate mine and natural gas mine, and also focused on the gas hydrate target forecast. The result shows that comprehensive geochemical anomaly and the thickness of permafrost can effectively differentiate gas hydrate between shallow gases; and the ratio of acid-extracted hydrocarbon and headspace gas heavy hydrocarbon can effectively delineate the gas hydrate target area. Eight gas hydrate wells (DK-1, DK-2, DK-3, DK-7, DK-9, DK12-13, DK11-14, and DK10-17) are in the target area, while all dry wells (DK-4, DK-10, DK10-16, DK10-18, DK7 -20, DK-6, DK6-21, and DK4-24) are in background area.

Key words: intensive gas hydrate geochemical exploration, gas hydrate target, permafrost, Sanlutian Qilian Mountains