The genesis of Methane in Weire 2 Well of Gushi Depression, Weihe Basin, Shaanxi Province, and its significance

The successful methane ignitions of Weire 2 well in Gushi Depression of Weihe Basin have drawn people's attention to the prospect of oil and gas resources in Weihe Basin again. Such analytical indices as natural gas components and methane carbon isotope of Weire 2 Well and its adjacent seven wells show that there are two kinds of genesis, i.e., Neogene biogenetic gas of Zhangjiapo Formation in the shallow part and Cenozoic coal pyrolysis gas in the middle and deep part. The indices also show that the associated CO2 is of organic origin. Geological analysis suggests that Gushi depression in Weihe Basin has a promising future of Cenozoic biogenetic gas, and pre-Cenozoic coal measures are important potential source rocks in Weihe Basin, which also provide source basis for further oil and gas survey in this area.