微破裂四维向量扫描影像裂缝监测技术在依兰煤层气区块中的应用

Application of Microfissure 4D Vector Scanning Image Fissure Monitoring Technology in Yilan CBM Block

煤层气储层的裂隙系统,总体上非均质性强,渗透率低,对煤层气产能起决定的作用,其低渗特征决定了大部分煤层气井需要进行水力压裂改造。应用微破裂四维影像监测技术,采用多波多分量数据采集和矢量叠加网格扫描的方法,实现压裂裂缝的三维立体显示,使煤层气储层压裂裂隙的解释更加直观,能够有效起到优化压裂方案和衡量压裂效果的作用。依兰煤层气区块首次应用该方法对压裂改造过程实时监测,得到了煤田主应力方向,获取了煤层气井压裂裂缝长度、高度及方位,认识了动态压裂过程中压裂裂缝的扩展规律,建立了煤层气井的压裂裂缝三维形态,对后续压裂设计和施工参数优化起到了一定的指导作用。

The fissure system in CBM reservoir has strong anisotropism and low permeability as a whole, played a decisive role in CBM productivity. Its low permeability features have dictated most CBM wells need to be hydraulic fracturing modified. To use microfissure 4D image monitoring technology, through multi-wave, multi-component data acquisition and vector superimposed grid scanning can realize fracturing fissure 3D stereoscopic display. Thus can make CBM reservoir fracturing fissure interpretation more intuitively, can effectively optimize fracturing scheme and judge fracturing effect. The Yilan CBM block has firstly applied the method carried out real time monitoring of fracturing modification process. Through the application has acquired coalfield principal stress direction, CBM well fracturing fissure length, height and bearing;known fracturing fissure propagation pattern;established 3D configuration of CBM well fracturing fissures. The study has certain guidance function for subsequent fracturing design and operation parameters optimization.