黔西南地区龙潭组页岩气储层特征

Longtan Formation Shale Gas Reservoir Features in Southwestern Guizhou

随着南方海相页岩气开发的突破,黔西南地区煤系泥页岩研究工作迫在眉睫。通过系统实验测试分析,以黔西南地区二叠系龙潭组页岩为主要研究目标,对该区页岩气成藏条件进行分析研究。结果表明,黔西南地区龙潭组含煤地层自北西向南东逐渐由陆相、海陆交互相演变为海相沉积,其内发育多段富含有机质泥页岩。有机质丰度相对较高,为0.60%～22.30%,平均4.37%;储层矿物成分以黏土矿物为主,为9.83%～95.23%,平均48.56%;等温吸附测试结果显示,龙潭组泥页岩最大吸附量为6.13m^3/t,含气潜力好。综上所示,基于黔西南地区泥页岩储层特征并结合构造保存条件分析,认为关岭岗乌—花江、普安地瓜—青山、兴仁巴铃—安龙龙山为页岩气成藏的有利区。本研究成果同时也可为中国南方地区龙潭组页岩气勘探提供借鉴。

Since the breakthrough in South China marine facies shale gas exploitation,so that the study on coal measures argillutite in the southwestern Guizhou is extremely urgent.Through systematic experimental test analysis,taking the Permian Longtan Formation shale in the area as the main subject investigated carried out analytic study on shale gas reservoiring condition.The result has shown that the Longtan Formation coal-bearing strata have a variation trend from northwest to southeast gradually varied from terrestrial facies,alternating marine-terrestrial facies to marine facies,and developed multiple organic matter rich argillutite.Their organic matter abundance is 0.60%～22.30%,average 4.37%,thus relatively high.The mineral composition of reservoir is mainly clay minerals,account for 9.83%～95.23%,average 48.56%.The results from isothermal adsorption test have shown that the maximum adsorptive capacity of argillutite is 6.13m 3/t with excellent gas-bearing potential.Based on above,analyzed the argillutite reservoir characteristics and structural preservation condition have considered that the Gangwu-Huajiang area in Guanling,Digua-Qingshan area in Puan,and Baling-Anlong Longshan area in Xingren are all favorable areas for shale gas reservoiring.The study can provide ample references for Longtan Formation shale gas exploration in South China.