Study on CBM Hosting Pattern in Panlong-Gaojiatun Exploration Area,Northern Shaanxi Triassic Coalfield
Shen Xiaolong;Lin Yabing;Jia Zhixin;Key Laboratory of Coal Resources Exploration and Comprehensive Utilization,Ministry of Land and Resources;Shaanxi Coal Geological Exploration and Research Institute Co.Ltd.;
The CBM enrichment pattern has impacted by multiple geological factors. On the basis of the Panlong-Gaojiatun exploration area CBM geological features analysis has discussed CBM enrichment pattern from buried depth,roof lithology and hydrogeology three aspects. The result has shown that the Wayaobu Formation in the study area has three pay grade coal seams namely Nos. 5,3 and 3~(-1). They are mainly thin coal seams with shallower buried depth,average R_(o,max) 0. 78%,stronger hydrocarbon generation capacity.Study area CBM average content is 0. 470m~3/t,slightly lower. The late Triassic Indosinian movement and early Cretaceous Yanshanian movement have made strata uplift and caused CBM dissipation,thus the key factor to bring about low CBM content. Exploration area CBM enrichment is mainly impacted by buried depth and hydrogeological condition. The lower CBM gas saturation has made impact on CBM enrichment from roof lithology inconspicuous.