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贵州下石炭统旧司组作为页岩气新区新层系勘探重点,近年来虽开展了大量的页岩气地质调查工作,但勘探效果甚微.本文在大量露头、钻井和测试分析资料的基础上,对其页岩空间展布特征、地球化学特征、页岩气储集特征和含气性特征进行详细分析,发现旧司组主要沉积于台盆和泻湖环境,黔西南地区干酪根类型主要为Ⅱ1和Ⅱ2型,在黔南地区主要为Ⅰ型,TOC主要分布于1％ ～ 2％.Ro值主要分布于1％～2.5％,区内热液矿物或温泉的影响不具区域性.页岩中石英含量多＞40％.旧司组下段页岩孔隙以宏孔为主,上段页岩孔隙呈中、宏孔并存.孔隙度主要分布2.0％～10.0％,储集性能中等.黔南地区目标层含气性良好,以吸附气为主.黔西南地区目标层以游离气为主,其含气性受断裂和目标层所处应力状态控制.在此分析基础上,结合勘探实践经验,采用综合信息叠合法初步优选出:望谟—紫云—罗甸、罗甸—克度和蟠龙—勺米3个有利勘探区,有利区面积约为1 448 km2.“,”The Lower Carboniferous Jiusi Formation in Guizhou Province is one of the key study areas for the exploration of shale gas in the new area and new strata.A large amount of the survey work had been carried out in it,however little progress had been achieved.In this work,we evaluated the geological characteristics of the Lower Carboniferous Jiusi shale (eg.the distribution,geochemical characteristics,reservoir properties of the shale and the total gas content of the core samples) on the basis of outcrops data,core samples and laboratory analysis.h can be concluded that the Jiusi Formation is deposited in the lagoon and interplattorm basin environment.The organic matter of the black shale is typed as kerogen Ⅱ1 and Ⅱ2 in the southwest of Guizhou Province,and typed as kerogen Ⅰ in the south of Guizhou Province.The total organic content of this samples are changing from 1％ to 2％.Ro is in the range of 1％ ～2.5％.The influence of the thermal anomaly,which is caused by the hydrothermal mineral and hot spring,is likely to have a local influence but not common in the hole region.The percentage composition of quartz is bigger than 40％.The reservoir space is in the form of huge hole and middle-huge hole in the lower and upper strata of Jiusi Formation respectively.The porosity of the shale is range from 2.0％ ～ 10.0％.The gas bearing capacity is good in the south of Guizhou Province.The gas is in the absorbing state in the key layer.In the southwest,the gas is in the free state,which is controlled by the fault and ground stress.Meanwhile,three sweet spots are recognized by intersecting multiple factors in one map on the basis of above work and practical experience.The three sweet spots are located in the region of Wangmo-Ziyun-Luodian,Luodian-Kedu and Panlong-Shaomi respectively.The total area of them is more than 1 448 km2.