多方位非零偏三分量垂直地震剖面方法在阿姆河右岸裂缝检测中的应用  

Application of Multiple Azimuth 3-component Nonzero-offset VSP Methods in Fracture Detection on the Right Bank of Amudarya Basin

作　　者：吕功训 刘合年 邓常念 陈仁金 

机构地区：[1]中石油阿姆河天然气勘探开发(北京)有限公司,北京100011

出　　处：《石油天然气学报》2014年第7期47-51,64,共6页Journal of Oil and Gas Technology

基　　金：国家科技重大专项(2011ZX05059)

摘　　要：非零偏三分量垂直地震剖面(VSP)记录中普遍存在着由下行纵波转换而来的下行透射横波,其携带着所经过地层的裂缝信息,可以用来检测储层裂缝。在横波分裂理论和前人研究的基础上,提出了基于多方位非零偏三分量VSP资料研究储层裂缝的方法。该方法分为3个步骤:一是通过2次水平旋转和上、下行波波场分离等预处理,获得研究裂缝所需的高质量下行横波;二是进行横波分裂处理,利用能量比法和互相关法获得独立的快、慢横波记录和裂缝发育方位;三是最终获得八方位裂缝发育方位和快、慢横波时差,根据地质统计学原理评估裂缝发育方向,快、慢横波时差估算裂缝密度。土库曼斯坦阿姆河右岸W1井八方位三分量VSP资料储层裂缝检测结果与成像测井结果总体上一致,验证了该方法的可靠性。Downgoing transmission S-wave converted from downgoing P-wave was generally presented in nonzero-offset 3-component VSP records,they carried fracture information of transient formation,and could be used to detect reservoir fractures.On the basis of Swave splitting theory and predecessors'researches,the method was proposed for studying reservoir fractures based on multi-azimuth nonzero-offset 3-component VSP data.The method contained three steps:the first was obtaining high-quality downgoing S-wave according to 2horizontal coordinate rotations and wave field separation of upgoing and downgoing waves;the second was S-wave splitting processing,independent fast and slow S-wave record and fracture azimuth were obtained by using the energy ratio method and the cross-correlation method;the third was eight-azimuth fracture orientation and fast-slow S-wave time difference were finally obtained to estimate fracture development orientation according to theory of geological statistics and estimate fracture density based on fast-slow Swave time difference.Eight-azimuth 3-component VSP fracture detection result of Well W1 on the right bank of Amudarya of Turkmenistan is generally coincident with FMI result,it is proven that the method is reliable.

关 键 词：非零偏VSP 下行转换横波 波场分离 时差 裂缝方向 裂缝密度 

分 类 号：P631.4[天文地球—地质矿产勘探]