利用潜在产气效率指数预测柿庄区块煤层气开发有利区

Using Potential Gas Production Efficiency Index to Predict Favorable Areas for Coalbed Methane Development in Shizhuang Block, Qinshui Basin

沁水盆地柿庄区块处于煤层气开发早期阶段,对煤储集层进行精细研究并预测开发有利区是下一步井位部署的重要依据。通过分析柿庄区块3号煤层特征,提出一套新的煤储集层定量表征方法,即选取含气量、厚度、渗透率、吸附时间作为表征参数,利用储气地质潜力、产气地质潜力和潜在产气效率指数分别反映煤储集层的资源丰度、产气潜力和潜在产气效率,并根据潜在产气效率指数进行煤层气开发有利区预测。研究表明,柿庄区块3号煤层资源丰度高,开发潜力大;区块的东部和中南部潜在产气效率指数较高,煤层气开发最为有利。该预测结果与现场煤层气井排采效果吻合度高,说明利用潜在产气效率指数预测煤层气开发有利区具有较高的可信度和可行性,对优选煤层气开发有利区具有重要的应用价值。

Coalbed methane(CBM)development in Shizhuang block of Qinshui basin is in the early stage,so detailed study on coal seams and prediction of favorable development areas should be very important for further well placement.Based on the analysis of No.3coal seam features in Shizhang block,a new set of quantitative characterization methods for CBM reservoirs is presented,that is to select gas content,thickness,permeability and adsorption time as characterization parameters,use coal reservoir gas potential,geological gas production potential and potential gas production efficiency index to reflect resource abundance,gas production potential and potential gas production efficiency,respectively,and predict favorable areas for CBM development based on the potential gas production efficiency index.The study shows that No.3coal seam in Shizhuang block has high resource abundance and great development potential.The potential gas production efficiency indexes are relatively high in the east and middle?south parts of the block,which should be the favorable areas for CBM development.The prediction results well match with the field pumping and producing efficiency,indicating that the method using potential gas production efficiency index to predict favorable CBM areas are reliable and feasible,which has great significance for favorable CBM area optimization.