这个问题是在反射地震成像速度建模(0公里和10公里之间沉积盆地)。这真的是一个岩石物理问题伪装成一个成像问题。* *我试图所做的简要描述:* *为了执行地震成像(又名地震迁移),我们假设地球是已知的速度结构。这让我们把记录反射振幅在正确的位置在三维空间中给我们的真实表示潜在地质(包括深度、下降和扩展反射系数)。我们可以获得这个横向不同迭代走时层析成像的速度模型相同的数据。我们通常占极地速度各向异性(即不同的速度相同的岩石,当测量平行和垂直于层理面)的形式(Thomsen参数)[1],在对称模型通常被称为创科实业(倾斜横向各向同性)。最终模型由5空间不同参数:-θ(角的结构性下降,假设对称轴垂直于层理)-φ(角结构罢工,假设对称轴垂直于层理)- V0(速度沿着这对称轴)-ε(Thomsen参数描述大角度各向异性的大小),δ(Thomsen参数描述小角各向异性的大小)θ和φ是容易获得直接从地震图像(这是为什么这个过程是迭代的一部分)。V0的初始模型,创建ε,三角洲从稀疏数据和获得进一步的细节之间利用断层控制点。在实践中,ε和δ是假定为线性相关,线性关系是整个数据集(这通常是一个很好的假设)。这让我们解决断层的只是两件事:V0和三角洲。 However, there is an intrinsic non-uniqueness, made worse by noise, in which different combinations of V0 and delta explain the data equally well (i.e. [image gather flatness][2]). **So the motivation for my question is this:** How can I use *a priori* geologic data to guide the solution of this ill-posed inverse problem? I am very skeptical about having the geologic structure guide V0 since my dataset is in an active foreland basin with strong active deltaic deposition. This means that my sediments (structurally deformed progradational sand-shale sequences) are very unconsolidated and compaction (therefore, depth) is the main driver of velocity rather than stratigraphy. In other words, I expect velocity contours to cross structural ones in areas of high dip (and I have evidence of these normal compaction trends from well data). **Which now leads to my question:** Can I use the geologic structure to guide my Thomsen delta (i.e. the degree of anisotropy)? Does it make sense to assume that even though compaction is the main driver for velocity in unconsolidated sediments, stratigraphy is the main driver of anisotropy? Maybe a more useful question: What other measurements or observations would I need to make to validate or reject this assumption? If this assumption makes sense, I can add the additional constraint (as a regularization term) to the tomographic inverse problem such that the solution for delta must (at least somewhat) follow the structural dip (i.e. theta and phi). Thanks! [1]: https://en.wikipedia.org/wiki/Transverse_isotropy#Thomsen_parameters [2]: http://www.subsurfwiki.org/wiki/Gather
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