塔里木盆地顺北区块二叠系井漏复杂的分析及对策

Analysis and countermeasures for complex Permian well leakagein the Shunbei block of Tarim Basin

顺北区块钻井项目施工中,二叠系的井漏复杂情况较多,漏失量大,易发生再次或多次漏失,严重时导致井壁垮塌掉块卡钻,致使井下复杂情况高发,给钻井工程带来损失,影响了该区块的勘探开发速度。二叠系火成岩发育,地层裂缝发育,地层破裂,钻井时井下复杂主要表现为漏失。针对此问题开展了顺北地区二叠系井漏复杂分析,结合顺北区块施工项目的实际情况以及二叠系地层特点,分析了该区块的二叠系钻进难点,总结了随钻堵漏技术具体的施工措施和不同漏速下的堵漏方案.经过实践验证,该综合防漏堵漏对策能有效减少井漏复杂,提高堵漏效率。

In the Shunbei block drilling work,there are many wells with complicate circulation loss in the Permian formation,such as large amount of leakage,second or multiple leakage.In some worse cases,it leads to collapse of the borehole and bit sticking,causing frequent down hole difficulties,bringing losses to the drilling project,and inhibiting the speed of exploration and development of the block.The down hole complex conditions exhibit mainly in the manner of leakage due to development of Permian igneous rock and strata fracture.In order to solve this problem,analysis of the complex Permian well leakage in the Shunbei area was carried out,and the Permian drilling difficulty in the area was analyzed in the light of the actual drilling situation in the Shunbei block and the characteristics of the Permian strata.This paper summarizes the concrete plugging-while-drilling measures and plugging schemes for leakage at different rates.Field results have proven that this comprehensive leak plugging strategy can effectively reduce complex leakage and improve the leak plugging efficiency.