伊朗南帕斯气田11区块防漏堵漏技术研究

RESEARCH ON LEAK PROTECTION AND PLUGGING TECHNOLOGY IN 11 BLOCK OF SOUTH PARS GAS FIELD,IRAN

井漏的产生必须具备两个基本条件,一是地层中存在能使钻井液流动的漏失通道,如孔隙、裂缝;二是井筒与地层之间存在能使钻井液漏失的正压差。南帕斯气田从上到下是一套以白云岩和灰岩为主的碳酸盐岩地质剖面,在成岩作用与构造运动作用形成的溶孔和裂缝是构成了南帕斯气田地层的主要漏失通道。其漏失压力系数小于1.0,因此使用海水钻井时均有可能发生井漏。文章对伊朗南帕斯气田11区块的邻井漏失案例进行总结,对影响钻探的井漏机理及原因进行分析,提出了钻开漏层前的预防措施,并对不同漏失层位的漏失制定了防漏堵漏对策,对该区块安全勘探开发具有积极意义。

Leakage passage and positive differential pressure between the bore hole and formation are two base conditions which cause lost circulation. South Pars gas field belongs to carbonate rock formation,its leakage pressure coefficient is less than 1. 0,so,the lost circulation is often occurred in South Pars gas field. Based on the leakage cases in 11 block of Iran's south Pars gas field,the mechanism of leakage was summarized,and the leakage causes were analyzed,and the corresponding preventive measures were put forward. These leak protection and plugging measures were used successfully in 11 block of Iran's south Pars gas field,and good effects were obtained.