S变换在低幅度构造识别中的应用——以准噶尔盆地腹部陆10—陆6井区为例

摘要

In the Lu10-Lu 6 well area in hinderland of Junggar Basin,the recognition of low-amplitude structure is the main task to seek low structural-lithologic reservoir,which is similar to Luliang Oilfield.The Hutubihe Formation,one of the major reservoirs in the study area,developed braided river sand bodies,its seismic event has poor lateral continuity,and there are few wells that unevenly distributed in this area,so it is difficult to trace horizons of low-amplitude structure precisely.The time-frequency analysis technique of S-transformation is used to establish the time-frequency response model of seismic cycle in S domain.Based on the joint calibration of two-dimensional spectrum and sedimentary cycle of single well,the isochronous sedimentary framework of the entire work area is built up.Finally,according to accurate horizon tracing which is controlled by the isochronous sedimentary framework,six low-amplitude structural traps are found,the total area is 221 km2,and two wells are optimized.The real drilling result proves the validity and practicability.%类似于陆梁油田的低幅度构造识别是准噶尔盆地腹部陆10—陆6井区的首要任务。该区的主力油层之一呼图壁河组多发育辫状河河道砂,其地震剖面同相轴横向连续性差,加之该区钻井少且分布不均,因此低幅度构造的层位精细等时追踪较为困难。针对这一难题,利用S变换时频分析特征,建立了典型沉积旋回体的地震旋回特征模型以及S域的时频响应特征模型,通过二维谱与单井沉积旋回联合标定,建立了整个工区精细的等时沉积格架。在高分辨率层序地层等时格架控制下进行杂乱地震反射特征的低幅度构造精细追踪,最终发现低幅度构造圈闭6个,叠合面积达221km2,综合评价优选上钻2口井位。经实钻分析,证明了该技术的有效性和实用性。