青海祁连地区三叠纪泥页岩地球化学特征及储集条件

青海省祁连地区三叠系分布广泛，含气暗色泥页岩系和碳酸盐岩发育。通过北祁连、南祁连地区的路线地质调查、钻探施工、样品测试和资料搜集对三叠系页岩地化特征、储层条件进行研究，结果表明：青海省祁连地区上三叠统厚度较大，有机质丰度多数属于低-中等，部分属于高-特高等，有机质类型以II1、II2型为主，部分地段有III型，有机质成熟度均达到低成熟-成熟阶段，具备形成页岩油气的地质条件。页岩中石英、斜长石、方解石等脆性矿物含量相对较高，岩性较致密，储集空间为孔隙和裂缝，属裂缝孔隙型储层，有利于后期改造。研究认为，青海省祁连地区三叠系具备较好的页岩气勘查前景。

An analysis of reservoir conditions and geochemical characteristics of the Triassic shale gas in Qilian region, Qinghai Province

Triassic strata with dark shale and carbonate rocks are widely distributed in Qilian region of Qinghai Province. In this paper, the route geology was surveyed, drilling was conducted, samples from North Qilian and Muli areas were analyzed, and data collected from south Qilian basin and north Qilian basin were collected. The results show that the thickness of Triassic is large. Most of the organic matters belong to low-medium abundance, with a small part belonging to relatively high- high abundance. The types of organic matters are mainly type II1 and II2, with a small part being type III. The maturity of organic matters have reached low mature - mature stage, within the maturity range favorable for the shale gas generation. The values of quartz, plagioclase mineral calcite and other brittle minerals of dark shale are relatively high. The space types of shale reservoirs mainly include two types of pores and cracks. In brief, Qilian Triassic shale shows good conditions for hydrocarbon source and has good exploration prospect.