可控震源组合方向对地震采集资料的影响分析

Influence of Vibrator's Combined Direction on Seismic Acquisition Data

随着各富油凹陷勘探开发程度的提高,针对复杂断块、地层岩性圈闭、低幅度构造、薄储层等油气藏的勘探已进入了精细勘探阶段,因而,对新采集地震资料的成像精度要求也越来越高。目前国内可控震源勘探均采用多台组合的形式施工,这种方法从理论上来说对地震采集的资料是有一定影响的,组合产生的时差问题会影响地质体的成像精度。通过模型正演及实际的野外地震采集资料分析发现,可控震源组合方向对静校正及地质体成像精度有较大影响,若多台震源组合,采用平行排列组合的方式所产生的误差变化相对简单,规律性较强,是一种相对较好的组合方式。可控震源组合也影响静校正量的精度,一般来说组合基距越小静校正量精度越高。

Along with the exploration and development of oil-rich depressions up-grading to a higher level,the exploration,amid at complex fault-block,lithologic trap,low amplitude structure and thin reservoir,has entered a stage of detailed exploration.Thus,precision requirement of new acquisition seismic data imaging is also getting higher and higher.Up to now,seismic data acquisition in China most uses the array with multiple vibrators.This method will influence the precision of seismic imaging.In this paper,forward modeling and actual field seismic acquisition data analysis showed that vibrators combination had greater impact on the direction of static correction and imaging accuracy of geological bodies.More than one source combination,arranged parallel to the combination,produced relatively simple error change and strong regularity.This is a relatively good combination.Vibrator portfolio also affects the accuracy of statics.Generally speaking,the smaller the array length,the higher the accuracy of statics.