WUMAYING BURIED HILL GAS RESERVOIR GEOLOGICAL AND GEOCHEMICAL CHARACTERS AND ORIGIN ANALYSIS
乌马营潜山天然气藏地质地球化学特征和成藏过程

Wumaying buried hill is a deeply buried one situated in south of Huanghua depression. Commercial gas reservoir originated and stored in Paleozoic was found at the weathering crust on the top of Ordovician when drilling Wushen-1 well. It's natural gas mainly originated from coal-bearing formation of C-P; Carbon isotope analysis, gas drying coefficient and naphthene index show that there is diversity in maturity of different component of the gas and the reverse carbon isotope series of gas, which indicate that the gas from Wushen-1 well is mixed by those in different maturation stages from the same source; Combined with the research on Wumaying paleo-structural restoration and Wushen-1 well fluid-inclusion it is found that Wumaying buried hill gas reservoir shows lately formed features, a result from early gas trap suffering destruction migration and getting mixed with lately generated gases.