黔西南晴隆页岩气勘探潜力研究——以石炭系旧司组为例

Study on shale gas exploration potential of Qinglong area in Southwest Guizhou: taking Carboniferous Chiussu Formation as an example

黔西南晴隆地区页岩气勘探具有一定潜力,利用新一轮地震资料及已钻井、野外露头等地质资料,开展地震反射层的地质属性定义、区域断裂系统研究、构造特征研究、圈闭描述及有利目标预测等工作,明确了晴隆地区石炭系旧司组页岩层纵横向展布情况,建立了区域断裂格架,发现2个有利背斜构造,指出页岩气勘探有利目标。综合分析认为:黔西南晴隆地区石炭系旧司组页岩层具有良好的深水盆地沉积环境;地震资料上页岩层呈明显的2～3个强相位、连续性较好的波峰反射特征,在横向上延展范围较广、可连续追踪;页岩层受区域断裂影响较小;发育多个背斜构造可形成有利圈闭,如碧痕营背斜、安谷背斜等大型圈闭;晴隆地区页岩气勘探具有较大潜力。

Qinglong area of southwest Guizhou has great potential in shale-gas exploration.According to a new round of seismic data and geological data of drilled wells and outcrops,it was carried out studies on the geological attribute definition of seismic reflection layers,the regional fracture system,the tectonic characteristics,the trap description,the prediction of favorable targeted layers,and so on.It was clearly identified the vertical and horizontal distribution of Carboniferous Chiussu Formation in Qinglong area and the grid of regional fracture was built.And then it was found two favorable anticline structures.Thus,it was pointed out the targeted area for shale gas exploration.The results of comprehensive analysis indicated that there is favorable depositional environment of deep-water basin in Chiussu shale layers of Qinglong area.The seismic dada showed that the sale layers have obvious reflection characteristics of 2 or 3 peak-waves with strong phase and better continuity,which has a wide range of extension and can be tracked continuously.The effect of regional fracture on shale is relatively small.Multiple anticline structures developed can form favorable traps,such as large-scale traps of Bihenying and Angu anticlines.Therefore,there is great potential in shale-gas exploration of Qinglong area.