川西致密砂岩气藏新的矿场评价标准和评价方法

文章根据川西致密砂岩气藏的损害特征和现场100多口井的测试资料的统计分析表明，储层表现出自身的损害特点，其常规的矿场评价指标和标准不一定完全适合非常规的致密碎屑岩气藏的情况，针对川西致密砂岩气藏损害特征，提出新的气藏损害的评价标准，同时根据致密砂岩气藏油层损害的要求和评价标准的需要，建立起新的描述裂缝-孔隙性砂岩气藏损害评价的数学模型，该模型在原来裂缝-孔隙性砂岩渗流模型的基础上考虑裂缝与基块之间窜流表皮系数对渗流物影响。将该矿场评价标准和评价方法应用于川西致密砂岩储层的损害评价中取得很好的效果，这不仅对于川西致密砂岩的油层损害评价有现实意义。而且对裂缝-孔隙油气藏的试井解释和损害评价都具有重要的指导意义。

NEW FIELD EVALUATION CRITERION AND METHOD FOR TIGHT SANDSTONE GAS RESERVOIRS IN WEST SICHUAN

Based on the damage characteristics of the tight sandstone gas reservoirs in west Sichuan and the statistical analysis of the testing data from more than 100 wells,it is shown that the reservoirs ar e of the characteristics of self damage and the conventional field evaluation n orms and criteria are not completely sure to suit to the unconventional tight fr agmental gas reservoirs.In view of the damage characteristics of the tight sands tone gas reservoirs in West Sichuan,a new criterion for evaluating gas reservoi r damage is proposed.In the light of the requirements of the tight sandstone g as reservoir damage and the evaluation criterion,a new mathematical model for de scribing the porous fractured sandstone gas reservoir damage evaluation is set u p.In this model,the effect of the channeling skin factor between the fracture an d matrix on the percolation flow is considered on the basis of the original perc olation flow model for fractured porous sandstone.By applying this field evaluat ion criterion and method to the damage evaluation of the tight sandstone reservo irs in West Sichuan,a good result has been obtained,which not only has a practic al significance for evaluating the tight sandstone reservoir damage evaluation b ut also has an important directive function both in the well test interpretation of the fractured porous oil and gas reservoirs and their damage evaluation.