南祁连盆地侏罗系聚煤规律及煤层气分布特征研究

Coal Accumulation and Distribution Characteristics of Coalbed Methane of Jurassic in Southern Qilian Basin

通过大量钻井岩心观察及样品测试分析,对南祁连盆地侏罗系地层煤层聚集规律及煤层气分布特征进行研究,认为南祁连盆地侏罗系含煤地层主要为木里组和江仓组,发育辫状河、辫状河三角洲和湖泊3种沉积体系。辫状河三角洲平原泥炭沼泽是最有利的聚煤场所。随煤层厚度增大,瓦斯含量及瓦斯中CH4的含量增加,由浅至深依次分为二氧化碳-氮气带;氮气-沼气带和沼气带。哈达-柴达尔地区和江仓-聚乎更-雪霍立一线,为2个瓦斯气中心带。

Though lots of dill cores and sample analysis,to study the coal accumulation and distribution characteristics of the coalbed methane of Jurassic in southern Qilian basin. It shows that the major coalbearing strata are Muli formation and Jiangcang formation,it has three kind of depositional systems: braided river,braided river delta and lake. The most important place of coal accumulation is braided river delta plain peat swamp. With the growth of the coal seam thickness,gas and CH4 in the gas content is increasing. It is carbon dioxide-nitrogen zone,nitrogen-biogas zone and biogas zone. Hada-Chaidaer and Cangjiang-Juhugeng-Xuehuoshan are two gas center zones.