For drilling the deep fractured carbonate conglomerate reservoir of the third section of Shahejie Formation in Daxing exploration zone of Langgu Sag, drilling mud losses can not be avoided, because of the lack of reservoir sensitivity information and the low pressure gradient of main producing formation. Considering Xing 9 reservoir geological characteristics and the drilling experience in recent years, some measures were taken to prevent drilling fluid leaking, as optimizing well scheme, strengthening the integration of seismic material and geological analysis while drilling, predicting fracture distribution before and after drilling, choosing suitable drilling fluid system according to different geological conditions, and controlling the slurry solid content. This method led to the success of overall drilling 10 wells, with drilling period down to an average of 105 days, and the average single well daily gas production more than 50,000 cubic meters, which indicated the studied method could protect fractured reservoirs and rapidly build up productivity. The successful application proved that the combination of geological and drilling process analysis is critical to solve complex geological problems in this area. Experiences were accumulated of drilling fractured conglomerate gas wells.%廊固凹陷大兴探区沙三段深层多套裂缝性碳酸盐岩砾岩体缺乏储层敏感性资料,主产层压力系数低,评价钻探中钻井液漏失等复杂情况时有发生.结合兴9气藏地质特征及近年来的钻井经验,提出采取优化井身结构、加强地震地质结合随钻跟踪,做好裂缝段钻前预测和钻后检测、根据不同目的层段的地质状况采用相应钻井液体系并做好防漏堵漏措施等措施来实现储层保护.现场应用10口井,钻井周期平均降至105 d,单井平均日产气5x10<'4>m<'3>以上,达到了保护裂缝储层、快速评价建产的目的.该方法的成功应用表明,地质随钻分析相结合是解决裂缝性砾岩气井钻探复杂地质问题的关键.
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