GeoEast处理系统在准南复杂高陡构造地区的应用

GeoEast seismic data processing in complex steep structure areas,Junggar Basin

霍玛吐背斜带下组合构造圈闭的落实程度是该区勘探突破的关键。以往地震资料由于受到表层复杂地震地质条件影响,干扰波极为发育,静校正问题严重,制约着地震资料在时间域和深度域的准确成像。地震成果在构造的主体部位波场复杂、资料信噪比较低,断裂解释存在多解性,圈闭特征及高点位置难以准确落实。为此,针对南缘高陡构造地区复杂剧变的近地表结构特点,在野外调查点资料的约束下,结合GeoEast处理系统的折射波野外静校正与井控初至波剩余静校正技术,基本解决了山前剧变地区复杂的静校正问题,形成了相对成熟的在时间域提高复杂高陡地区资料信噪比的技术流程。面对复杂多样的各类干扰波,利用GeoEast处理系统的叠前四维去噪等特色技术中的叠前分频多域去噪模块,在时间域大幅度提高了叠前道集资料信噪比,并为在该区开展叠前深度偏移精细速度建模提供了高品质的基础资料,提高了深度域成像精度。

Complex near-surface conditions in the steep structure area of Huomatu cause strong interferences and serious statics problems on seismic data,which harms seismic data imaging in the time and depth domains.Complicated wave field and low SNR make fault interpretation very difficult.Onaccount of the complex characteristics of near-surface in highly-steep and complicated structure in the area,we use the refraction static corrections and well-control first-break residual static corrections provided by GeoEast to solve complex statics problems in piedmonts and improve seismic data SNR in the time domain.For complex interferences, we adopt pre-stack frequency-dependant multi-domain denoising approach and pre-stack random noise removal to improve SNR of pre-stack gathers in the time domain.This high quality data is very helpful for pre-stack depth migration velocity modeling.Finally the data imaging by pre-stack depth migration is greatly improved in the depth domain,which provides a good basis for trap interpretation.