CAJ | 학술논문

浅层高分辨率地震勘探是城市活断层探测手段中最有效、最可靠的方法之一,但是由于隐伏活断层勘探时存在着勘探深度浅、地层的属性差异小以及环境噪声大等因素,导致地震勘探数据信噪比低、反射信号弱等问题,严重影响地震数据的采集、处理和解释.采用一阶应力-速度方程的高阶交错网格有限差分方法, 结合完全匹配层(PML)的边界处理方法和通量校正(FCT)法消除频散的技术手段,对活断层模型地震勘探进行正演模拟,清晰直观地表现了断层处的细微差别,有助于地震勘探中对信号的分析与理解.结果表明,这些处理手段结合波动方程有限差分算法,能够有效实现薄层、弱反射的隐伏活断层模型的波场正演模拟,可有效识别隐伏活断层的断层倾角、断距、规模、跨越范围、断层深度以及断裂带影响范围,为分析这些参数对地震记录的影响提供有力帮助,同时结合实测地震数据的处理、解释,为防灾减灾提供具体有力的判据.
천층고분변솔지진감탐시성시활단층탐측수단중최유효、최가고적방법지일,단시유우은복활단층감탐시존재착감탐심도천、지층적속성차이소이급배경조성대등인소,도치지진감탐수거신조비저、반사신호약등문제,엄중영향지진수거적채집、처리화해석.채용일계응력-속도방정적고계교착망격유한차분방법, 결합완전필배층(PML)적변계처리방법화통량교정(FCT)법소제빈산적기술수단,대활단층모형지진감탐진행정연모의,청석직관지표현료단층처적세미차별,유조우지진감탐중대신호적분석여리해.결과표명,저사처리수단결합파동방정유한차분산법,능구유효실현박층、약반사적은복활단층모형적파장정연모의,가유효식별은복활단층적단층경각、단거、규모、과월범위、단층심도이급단렬대영향범위,위분석저사삼수대지진기록적영향제공유력방조,동시결합실측지진수거적처리、해석,위방재감재제공구체유력적판거.
The shallow high-resolution seismic prospecting is one of the effective and reliable methods in urban active fault detection. For the shallowness of the object stratum, the tiny difference between the seismic attribute of strata and the ambient noise, it is hard to process and interpret seismic data. In this paper, the staggered-grid high-order difference method of one-order elastic wave equations, which are expressed with velocity and stress applying the flux-corrected transport(FCT) method with a perfectly matched layer (PML) absorbing boundary condition, are used to obtain the synthetic common-shot profile for shallow fault model. The simulated results of fault model show that this method is accurate and distinct. This seismic modeling method is helpful for approximately estimating the location, the depth and the scope of the fault from the synthetic profile during survey, and improving the efficiency of seismic prospecting and the precision and resolution of seismic data processing and interpretation.