青海江仓矿区煤储层特征及煤层气资源评价

Characteristics of Coal Reservoir and Resource Evaluation of Coal-bed Gas in Jiangcang Mine Area of Qinghai Province

青海木里煤田江仓矿区含煤面积大,煤炭资源丰富。结合木里煤田江仓矿区地质情况分析了煤储层特征,在使用吸附法分析矿区煤样晶的基础上,探讨了该区微观空隙结构以及割理对煤层气的影响作用。体积法也被用于计算江仓矿区地质资源量。结论为:①江仓矿区煤厚变化大、总厚度大、煤层间距小,有机组分以镜质组和惰质组为主,壳质组含量很少,这些均有利于煤层气的形成;②研究区储层物性较好,有利于煤层气的赋存及开采;③江仓矿区地质资源量共57.41亿m3,平均资源丰度1.04亿m3/km2。

There exist macro lithotypes of coal in Jiangcang mine area of Mull coal field in Qinghai Province, and it is considered that this place has huge numbers of coal reservoir. According to the geological condition of Jiangcang mine area of Mull coal field,the characteristies of coal reservoir were analysed,the influences of microcosmic pore structure and cleat to coal-bed gas were discussed based on adsorption method applied for the analysis on coal samples in mine area. Volume method was also used to calculate the resources in Jiangcang mine area. The conclusion was drawn that：firstly,the coal thickness is various in Jiangcang mine area,the whole thickness of coal seam is large,and the seam spacing is small. Organic composition of coal is mainly vitrinite and inertinite while exinite content is iow. All of the above are helpful for the formation of coal-bed gas. Secondly,reservoir physical property in searched area is well, and this is helpful for the storage and mining of coal-bed gas. Thlrdly,the resource amount is 5741 million m3 and the average resource abundance is 104 million m3/k㎡.