川南深层五峰—龙马溪组页岩工程“甜点”地震预测技术  

Seismic Prediction Technology for Engineering“Sweet Spot”of Deep Wufeng-Longmaxi Formation Shale in Southern Sichuan

作　　者：赵爽[1] 李曙光[1] 林正良[2] Zhao Shuang;Li Shuguang;Lin Zhengliang(Research Institute of Exploration and Development,Sinopec Southwest Oil&Gas Company,Chengdu Sichuan 610095,China;Research Institute of Petroleum Geophysical Prospecting Technology,Sinopec,Nanjing Jiangsu 211103,China)

机构地区：[1]中国石化西南油气分公司勘探开发研究院,四川成都610095 [2]中国石化石油物探技术研究院,江苏南京211103

出　　处：《工程地球物理学报》2022年第4期466-473,共8页Chinese Journal of Engineering Geophysics

基　　金：中国石化科技部重点科技项目(编号:P18058-1)。

摘　　要：页岩气是人工改造气藏,好的压裂改造效果是页岩气井获得高产的关键,通过地球物理方法对页岩储层参数进行预测,判断页岩是否为工程“甜点”,是页岩气地球物理研究的重要内容。以地震弹性参数反演为基础,引入E/λ脆性系数表征页岩脆性,利用改进的CPS模型计算页岩正常压实趋势提高地层压力预测精度,基于线性滑动理论地应力预测技术确定地应力方向及水平应力差率,实现页岩储层的脆性、地层压力、地应力预测,形成页岩气工程“甜点”地球物理预测技术系列。在川南深层龙马溪组进行优质岩页工程“甜点”地球物理预测应用,表明脆性较高、地层压力系数高、水平应力变化率小的区域为页岩气工程“甜点”,是压裂改造易于压开、易于形成复杂缝网的优势储层。页岩的工程“甜点”地球物理预测为页岩气的地质—工程一体化研究提供了重要参数,支撑页岩气的综合评价、水平井部署、压裂设计,是页岩气高质量勘探及高效开发的保障。Shale gas is an artificially modified gas reservoir,and a good fracturing effect is the key to its high production.An important content of shale gas geophysical research is to predict shale reservoir parameters by geophysical methods and determine whether shale is an engineering sweet spot.Based on seismic elastic parameter inversion,the E/λbrittleness coefficient is introduced to characterize the brittleness of shale.When calculating the normal compaction trend of shale,the improved CPS model is used to improve the prediction accuracy of formation pressure.Based on the in-situ stress prediction technology of linear sliding theory,the in-situ stress direction and horizontal stress difference rate are determined to realize the prediction of brittleness,formation pressure,the in-situ stress of shale reservoirs and a series of“sweet spots”geophysical prediction technology for shale gas engineering.The“sweet spot”geophysical prediction application of high-quality rock shale engineering in the deep Longmaxi formation in southern Sichuan shows that areas with high brittleness,high formation pressure coefficient,and low horizontal stress change rate are the“sweet spots”of shale gas engineering,which is the dominant fracturing reservoir and liable to open and form complex fracture networks.The engineering“sweet spot”geophysical prediction of shale provides important parameters for the integrated geological-engineering research of shale gas,and supports the comprehensive evaluation of shale gas,horizontal well deployment,and fracturing design.It is a guarantee of high quality exploration and efficient development of shale gas.

关 键 词：工程甜点 地震预测 脆性 地层压力 地应力 

分 类 号：P631.4[天文地球—地质矿产勘探]