GENETIC TYPE AND SOURCE OF THE NATURAL GAS IN HUO-MA-TUO ARTICLINE ZONE IN THE SOUTHERN JUNGGAR BASIN

The Huo-Ma-Tuo articline zone in the southern Junggar Basin is a tectonic zone suffered complicated tectonic deformation and evolution. Its geological conditions are very complex and its petroleum accumulation conditions, especially the origin of hydrocarbon have remained controversial. This paper used the three characteristics of the natural gas from the newly discovered hydrocarbon reservoir, i.e. the characteristics of component, carbon isotope and light hydrocarbon, to recognize the genetic type of natural gas and gas source in each articline. The analysis of components shows that the natural gas is an organic wet gas or mainly the humic kerogen cracking gas. Carbon isotope analysis indicates that the natural gas is mainly coal-related gas, including pyrolytic gas and kerogen cracking gas. The light hydrocarbon analysis, however, shows that the natural gas is a typical coal-type gas. Based on these results, it is concluded that the natural gas in Huo-Ma-Tuo articline zone is mainly derived from the Jurassic coal-bearing formation, including pyrolytic and kerogen cracking gases.