致密砂岩储集层裂缝综合录井识别技术研究

Study on the comprehensive mud logging identifying techniques for the tight sandstone reservoir fracture

四川盆地油气勘探结果表明,盆地油气储集层普遍为致密砂岩非常规储集层,有效性主要取决于孔、洞、缝发育程度,因此在油气钻井中如何识别致密储集层的孔、洞、缝并确定其所在井段尤其重要。针对综合录井仪的0.1m钻时及相关参数的资料采集技术要求,通过对大量录井数据资料的统计和演算,建立起储集层裂缝发育程度及裂缝发育位置的3种储集层裂缝识别模型,即直接识别模型、地层可钻性(A值)识别模型、钻时回归(RWSR)值识别模型。系统阐述了致密砂岩储集层裂缝综合录井识别技术方法原理,详细介绍了致密砂岩储集层裂缝识别的3个模型在实际生产中的应用情况。该技术方法的研究在国内尚属首次,为油气勘探中储集层评价提供了一个新的方法和手段,可最大限度地发挥现代录井技术在油气勘探开发过程中的作用。

Oil and gas exploration results from Sichuan Basin indicated its oil and gas reservoirs generally were dense type of unconventional reservoirs, their efficiencies mainly depended on aperture, cavity and seam growth extent, so, how to identify aperture, cavity and seam from the tight reservoirs and determine the intervals were very important. In view of mud logging unit with the 0.1 m drilling time and data acquisition specification requirements for the correlation parameters, through making statistics and calculation to a vast sum of mud logging data, three reservoir fracture identification models were set up, which determined reservoir fracture development extent and fracture development position, that is, direct identification model, formation drillability (value A) identification model and drilling time regression value (RWSR) identification model. The paper systematically expounded the principles of mud logging identification technique methods for the tight sandstone reservoir fracture, summed up three models for identifying the tight sandstone reservoir fractures, and gave a brief introduction for the applied situation of this technique in actual production. It was the first study of these domestic technical methods and provided a new method and means for the reservoir evaluation during oil and gas exploration, therefore, bringing modern mud logging techniques into full play during oil-gas exploration and development.