利用多属性断裂分析技术识别断层——以牙哈断块潜山为例

Fault and fracture identification with seismic multi-attributes:an example of Yaha fault-block buried hills

利用GeoEast软件重新处理三维地震资料,通过分析三维地震、地质与钻井资料,开展牙哈富油气区带深层寒武系潜山内幕油藏整体再评价。利用相干、曲率等多属性分析定量识别断裂,在此基础上,精细刻画了牙哈逆冲及走滑断裂活动特征,分段剖析了潜山断裂控储机理。得到以下认识:①牙哈大断裂的强烈逆冲与多期构造演化是控制寒武系岩相展布、改善白云岩储集性能、形成牙哈白云岩断块潜山的主控因素。②不同地震属性仅仅反映了不同尺度的断裂,因此在研究过程中要综合利用多属性分析。③受构造演化控制,寒武系储层发育三期裂缝:第一期形成于加里东—早海西期,处于埋藏成岩作用的早期;第二期形成于晚海西期—印支期,处于牙哈构造带整体抬升阶段;第三期形成于燕山中晚期—喜马拉雅早中期。

Combining with geological and drilling data,an overall re-evaluation of deep Cambrian buried hill reservoirs in Yaha rich oil and gas area is carried out based on 3 Dseismic reprocessed by GeoEast System.Fractures are quantitatively identified with coherence and curvature analysis.Then thrust faults and strike-slip faults are characterized,and the reservoir mechanism is discussed.The following understandings are obtained:(1)The early strong thrust of Yaha faults was the main controlling factors that has affected the denudation of fault blocks,affected the reservoir development and hydrocarbon enrichment;(2)Different seismic attributes only reflect fractures of different scales,so multi-attribute analysis should be comprehensively used in the research process;(3)Controlled by tectonic evolution,the Cambrian reservoir development had three stages:the first stage formed in the Caledonian-Early Hercynian period,it is in the early stage of burial diagenesis;the second stage formed in the late Hercynian-Indosinian period,which is in the overall uplifting stage of the Yaha structural belt;the third stage formed in the middle and late Yanshanian-Himalayan early and middle stages.