基于源波场照明的逆时偏移振幅补偿方法

发布时间：2018-01-30 14:06

本文关键词： 逆时偏移单炮源波场照明均炮源波场照明振幅补偿　出处：《科学技术与工程》2017年31期 　论文类型：期刊论文

【摘要】：逆时偏移作为一种先进的地震成像方法,能够适应横向变速和高陡倾角等复杂地质构造成像。但在对逆掩断层等复杂地质构造进行逆时偏移成像时,由于断层对地震波场的屏蔽效应,导致其下盘地质构造成像振幅很弱。一般采用单炮源波场照明除互相关成像来对深层构造弱振幅成像进行补偿,这种单炮源波场照明补偿方法虽然简单,但在地质构造特别复杂时会导致波场照明空间变化剧烈,从而影响成像振幅的补偿效果,加重了背景假像和噪音。为了克服这一问题,提出均炮源波场照明补偿方法,即用均炮源波场照明除互相关成像来进行弱振幅补偿,均炮源波场照明是指利用某一炮附近邻域内所有单炮源波场照明的均值来代替该炮源波场照明。对于复杂构造,由于均炮源波场照明空间变化较平缓,在进行逆时偏移成像振幅补偿时,背景假像和噪音也能得到很好的压制。根据实际地质构造设计了一个逆掩断层理论模型来验证均炮源波场照明振幅补偿的效果,并和单炮源波场照明振幅补偿进行了对比。
[Abstract]:As an advanced seismic imaging method, reverse time migration can be used for imaging complex geological structures such as lateral velocity change and high steep dip, but it can be used in the imaging of complex geological structures such as thrust faults. Because of the shielding effect of fault to seismic wave field, the amplitude of geologic structure imaging is very weak. In general, the weak amplitude imaging of deep structure is compensated by single gun source wave field illumination and cross-correlation imaging. Although this method of single-gun source wave field illumination compensation is simple, it will lead to drastic changes of wave field illumination space when the geological structure is especially complicated, thus affecting the compensation effect of imaging amplitude. In order to overcome this problem, a compensation method of equal-shot source wave field illumination is proposed, which is to compensate the weak amplitude by using the average gun source wave field illumination and cross-correlation imaging. The average source wave field illumination refers to the use of the mean value of all the single gun source wave field illumination in the neighborhood near a gun to replace the gun source wave field illumination. For complex structures, the illumination space of the uniform gun source wave field changes slowly. In reverse time migration imaging amplitude compensation. Background falsehood and noise can also be suppressed well. According to the actual geological structure, a theoretical model of thrust fault is designed to verify the effect of amplitude compensation of average gun source wave field illumination. And compared with single gun source wave field illumination amplitude compensation.
【作者单位】：防灾科技学院;中石油东方地球物理公司;
【基金】：中国地震局教师科研基金(20150101) 国家自然科学基金(21504014,41674055)资助
【分类号】：P631.4
【正文快照】： 引用格式:杨仁虎,凌云,瞿立建,等.基于源波场照明的逆时偏移振幅补偿方法[J].科学技术与工程,2017,17(31):23—28Yang Renhu,Ling Yun,Qu Lijian,et al.Reverse time migration ampli-tude compensation based on source illumination[J].Science Technologyand Engineering,2

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