基于组合模型的薄互层瞬时属性特征研究  

Study on the instantaneous attributes characteristics of thin interbed based on combination model

作　　者：张刘[1] 李琼[1,2] 姚文[1] 罗方兵 李沆 

机构地区：[1]成都理工大学地球物理学院,四川成都610059 [2]成都理工大学地球探测与信息技术教育部重点实验室,四川成都610059

出　　处：《油气地球物理》2015年第3期50-57,共8页Petroleum Geophysics

基　　金：国家自然科学基金(41274129);国家科技重大专项(2011ZX05035)联合资助

摘　　要：针对楔状、递变型、不同砂地比及反射系数相差较大等薄互层模型,通过正演模拟,结合复数道,详细分析了瞬时振幅、瞬时频率等属性特征。研究发现,不同模型对应不同的瞬时属性特征。楔状模型,当0<t<T/2时,瞬时振幅随时间厚度增大而增大,当T/2<t<T时,呈负相关;当0<t<3T/4时,瞬时频率与厚度负相关。不同砂地比模型,瞬时振幅值随砂地比增大而增大,但在同一砂地比下,不同内部组合,瞬时属性也会有差异。等厚递变型模型的瞬时属性值偏向反射系数大的一侧,且瞬时频率倾斜程度更大。当反射系数由少变多,且极性变化时,瞬时属性特征也会越来越复杂。通过正演模拟可以定性分析不同薄互层瞬时特征,为薄互层地质解释提供理论依据。Aimed at the different thin interbed models, such as wedge, graded, different sand ratio models and the models which have reflection coefficients with large difference, the seismic response characteristics and the instantaneous attributes, such as instantaneous amplitude and instantaneous frequency, are analyzed in details by forward modeling and complex trace analysis. The result show that the different models have different instantaneous attribute characteristics. For the wedge model, the instantaneous amplitude increases with the increase of time thickness when it is from zero to T/2, but there is a negative correlation when T/2<t<T, the instantaneous frequency decreases with the increase of time thickness it is from zero to 3T/4. For the different sand ratio models, the instantaneous amplitude value increases with the increase of sand ratio, but the instantaneous attributes also have differences for different internal combination in the same sand ratio. For the isopachous graded model, the instantaneous attribute value will lean to the big reflection coefficient, and the tilt degree of instantaneous frequency is larger. The instantaneous attributes characteristics also will become more and more complicated when the reflection coefficients become more and more and the polarities are changed. The instantaneous attribute characteristics of different thin interbed models could be analyzed by forward modeling,and the theoretical basis are provided for the thin interbed geologic interpretation.

关 键 词：薄互层 正演模拟 复数道分析 瞬时振幅 瞬时频率 

分 类 号：P618.130.8[天文地球—矿床学]