摘要
地震波在地下介质中传播时,由于地下介质的吸收衰减作用,地震波的部分弹性能量不可逆转的转化为热能而发生耗散,使得地震波的能量发生衰减,相位产生畸变,降低了地震资料的分辨率和信噪比。为了实现对地震波的吸收衰减进行补偿,国内外许多学者在这方面做了大量的研究工作。笔者简单介绍了地震波的衰减机制和影响地震波衰减的主要因素,重点概括了各种地震波衰减补偿的研究方法,如反Q滤波方法、时频分析方法和反Q偏移方法,分析了各种补偿方法的优缺点。最后用黏声波逆时偏移方法对地震波衰减进行了补偿,并预测了地震波衰减补偿研究的发展趋势。
The energy in seismic waves will be absorbed when the waves travel in the earth,because the medium in the earth is viscoe?lastic.There are many kinds of energy absorption,such as geometric spreading,intrinsic attenuation, transmission losses,and energy conversion.Such energy absorptions will decrease the signal?to?noise ratio and the resolution of seismic data.In order to realize the ener?gy compensation,many scholars both in China and abroad have tried their best to do a lot of work. In this paper,the seismic attenuation mechanism and the main factors affecting the seismic wave absorption were reviewed.Several kinds of methods of energy compensation for seismic absorption attenuation including inverse Q filtering ,time?frequency analysis and inverse Q migration were emphasized.An a?nalysis shows that these methods have their own advantages and disadvantages.The authors implement the viscoacoustic wave equation for the forward and backward wave propagation to correct the attenuation effects in reverse time migration.A numerical test demonstrates that the attenuation effects in reverse time migration can be properly compensated and the attenuation compensation can enhance the high?wavenumber components in complex geological structures.Finally,the development trend of seismic wave energy compensation is forecasted.
出处
《物探与化探》
CAS
CSCD
2015年第3期456-465,共10页
Geophysical and Geochemical Exploration
基金
国家自然科学基金项目(41204086)
国家科技重大专项项目(2011ZX05006-002)
关键词
吸收衰减
品质因子
能量补偿
反Q滤波
时频分析
反Q偏移
absorption attenuation
quality factor
energy compensation
inverse Q filter
time-frequency analysis
inverse Q migration
