不同地震属性的方位各向异性分析及裂缝预测  

Azimuthal anisotropy analysis of different seismic attributes and fracture prediction

作　　者：王洪求[1,2] 杨午阳[1] 谢春辉[1] 郑多明[3] 王海龙[1] 张喜梅[1] 蒋春玲[1] 

机构地区：[1]中国石油勘探开发研究院西北分院,甘肃兰州730020 [2]CNPC油藏描述重点实验室,甘肃兰州730020 [3]中国石油塔里木油田分公司勘探开发研究院,新疆库尔勒841000

出　　处：《石油地球物理勘探》2014年第5期925-931,820-821,共7页Oil Geophysical Prospecting

基　　金："十二.五"国家科技重大专项(2011ZX05004-003)资助

摘　　要：通过对塔里木盆地热瓦普区块宽方位地震资料分析认为,在方位角划分时应尽可能多地利用远炮检距信息,有利于提高裂缝预测精度。通过计算和分析不同地震属性的各向异性表明:旅行时差相对于旅行时,其各向异性受上覆地层的影响更小,较真实地反映目的层裂缝发育情况;振幅的各向异性预测裂缝的规律性较好,且与区域断裂分布特征吻合程度高;AVO梯度的各向异性预测裂缝精度高于常规属性,且在串珠位置(即缝洞发育处)裂缝发育,与实际地质情况吻合。对旅行时差、振幅、AVO梯度等有利属性的各向异性结果进行融合,可提高裂缝预测精度,有利于指导高产井的部署。Through analysis of wide azimuth seismic data in Rewapu area,we understand that far-offset information helps fracture prediction improvement when dividing azimuth.Based on calculation and analysis of anisotropy about different attributes,interval traveltime anisotropy could weaken impact on the overlying strata relative to traveltime anisotropy,and it can represent real fracture characteristics of the target.Amplitude anisotropy reveals better fracture distribution,and complies greatly with fault characteristics.AVO gradientanisotropy has higher accuracy than that of amplitude anisotropy in fracture prediction.This kind of fractures is always developed at bead-like seismic reflection with caves.Fusion of beneficial attributes such as interval traveltime anisotropy,amplitude anisotropy,and AVO gradient can improve fracture prediction.

关 键 词：方位角 裂缝预测 旅行时 AVO梯度 各向异性 

分 类 号：P631[天文地球—地质矿产勘探]