对于裂缝发育等破碎性地层,在井筒内外压差作用下钻井液极易沿裂缝等天然通道侵入地层,致使近井裂缝发育带孔隙压力增加,引发泥页岩水化膨胀及强度性能下降,导致坍塌压力增加,从而使得井壁垮塌越加严重,搞清破碎性地层垮塌机理至关重要.结合延安气田石盒子和石千峰组裂缝性泥页岩"越提密度、垮塌越严重"井塌处理误区,指出缺乏对裂缝有效封堵是症结所在.为此提出适用于裂缝发育等破碎性地层"封堵为先、抑制水化、合理密度"的防塌技术对策,在此基础上,优选出延安气田强封堵钻井液配方并在现场成功应用,相关技术思路及研究成果可为类似破碎性地层防塌提供参考.

本文首先分析了延安气田钻井过程中存在的主要问题,其次针对问题优选出了一套有利于防漏防塌、保护气层及安全、快速钻井的钻井液技术,以提高延安气田的综合勘探经济效益.

安14平1井是延长石油集团油气勘探公司钻井工程部5001队在延安区块承钻的一口水平井,该井地处典型的鄂尔多斯盆地伊陕斜坡.本文首先分析了安14平1井在施工过程中的难点,其次针对难点分别提出了钻井液技术及井眼轨迹控制技术等工艺措施,并通过这些措施的实施取得了良好的效果,该井的顺利完井为同类油气田钻井施工工作提供了良好的技术参考.

通过一口典型井电测遏阻情况分析,针对引起电测遏阻的地层原因、工程技术措施、钻井液技术措施等原因制定针对性预防措施,降低完井电测遏阻事故发生.

The main controlling factors of chang6 reservoir in Yanchang area are discusses through using the log information,testing and analytical information such as Casting section,scanning electron microscope,grain size analysis and penetration et al.The results show that Chang 6 reservoir belongs middle-low hole and ultralow reservoir.The collection condition get better up and storage space up giving first place to intergranular pore under the late diagenetic stage make over effect.The distribution storing the collection ability pattern up is controlled mainly by spread law of depositing micro-face and the diagenesis.The micro-rift of part growth has the certain effect to improving reservoir property.Reservoir property of underwater distrbutary channel sandstones and debouch bar sandstones is best on plane distribution.And droop over to being controlled on evolution by diagenesis,the compaction and the cementation make reservoir nature be changed into difference obviously,the secondary pole that the dissolution produces improves the reservoir porosity and permeability,forms the effective reservoir.