低渗透气藏水平井优化部署及地质导向钻进方法研究与实践——以苏里格气田东区南部为例

Optimization and Deployment of Low-Permeability Gas Reservoir Horizontal Well; Study and Practice of Geological Steering Drilling Method——Taking Southern Part of Eastern Block of Sulige Gas Fieldfor Example

水平井开发技术对于低渗透气藏具有提高单井产量和气田开发效益的独特优势。以砂体精细描述及储层评价为重要手段,优选水平井开发有利目标区;针对苏里格气田东区南部上、下古生界储层发育特点,以立体开发、整体开发及大井丛水平井组开发部署结合的方式,进行水平井优化部署;水平井设计根据不同的砂体及有效砂体发育特点,采用平直型、顶穿底型及阶梯型3种水平段轨迹;地质导向以提高储层钻遇率为目标,以入靶跟踪和水平段跟踪调整为核心,形成4种靶点调整和6种轨迹控制的水平井地质导向跟踪技术。研究成果应用于水平井开发中效果良好,获百万方高产井2口,有效储层钻遇率最高达91.6%。

Development technology of horizontal well has unique advantages to improve single-well production of low-permeability gas reservoir and improve overall economic performance of gas fields. Detailed sand body description and reservoir assessment are used as important means to optimize and select favorable target zones for horizontal well development. Aiming at the development characteristics of Upper and Lower Paleozoic reservoirs in the southern part of the eastern block of Sulige Gas Field, the efforts were focused to optimize and deploy horizontal wells on the basis of overall development including a large cluster of horizontal wells. Horizontal well can be designed according to the development characteristics of different sand bodies and efficient sand bodies. Three trajectories of horizontal sections can be adopted--- straight horizontal, from-top-to-bottom horizontal and gradient horizontal. Geological steering should be aimed at improving the drilling success rate of reservoir. Adjustment should be focused on tracing of target and tracing of horizontal section, thus developing a series of horizontal well geological steering tracing technologies, including four technologies for adjustment of target point and six technologies of trajectory control technologies. The study has achieved good results when used for horizontal well development. Two wells produced 1 million cubic meters of gas each while the effective drilling success rate of reservoir was improved 91.6 percent.