3D inversion of large-scale frequency-domain airborne electromagnetic data using unstructured local mesh
3D inversion of large-scale frequency-domain airborne electromagnetic data using unstructured local mesh
复制标题
使用非结构化局部网格对大规模频域机载电磁数据进行 3D 反演
DOI：
10.1190/geo2020-0243.1
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发表时间：
2021-05
期刊：
影响因子：
3.3
通讯作者：
Bin Xiong
中科院分区：
文献类型：
--
作者：
Zhang Bo;Changchun Yin;Yunhe Liu;Xiuyan Ren;Vicas C. Baranwal;Bin Xiong
航空电磁法在矿产勘查、环境与工程研究、地下水调查等领域得到了越来越广泛的应用。然而，与大地电磁法或可控源电磁法等地基电磁法相比，AEM方法通常产生大量数据，这导致非常昂贵的三维电磁反演。我们已经开发了一个新的三维AEM反演方案的基础上有限元方法和非结构化四面体局部网格。这是不同于传统的局部网格方法，传统的方法使用规则的长方体的三维AEM反演，而我们的计划使用不规则的四面体网格，可以很容易地适应地形和复杂的地下结构。此外，由于我们通过从全局模型网格的一部分提取来创建我们的局部网格，因此局部网格和全局网格之间的关系是直接的，因此我们可以很容易地创建全局和局部网格之间的雅可比矩阵的投影，并快速构造用于3D EM反演的全局雅可比矩阵。在基于有限元方法制定边界值问题后，我们通过检查均匀半空间模型的半解析解来验证我们的建模算法的准确性，并通过对挪威Vesterålen收集的合成和调查数据进行反演来测试我们的反演算法。数值实验表明，该方法可以高精度地模拟AEM响应，并从合成数据和实测数据中恢复地下主电阻率结构。
Airborne electromagnetic (AEM) methods have been more and more widely used in mineral exploration, environmental and engineering studies, and ground water investigation. However, compared with ground-based electromagnetic (EM) methods, such as magnetotelluric or controlled-source EM, AEM methods generally produce large amounts of data, which leads to very costly 3D EM inversions. We have developed a new 3D AEM inversion scheme based on the finite-element method and unstructured tetrahedral local meshes. This is different from the traditional local mesh method in that the traditional method uses regular cuboids for 3D AEM inversions, whereas our scheme uses irregular tetrahedral meshes that can easily accommodate the topography and complex underground structure. Moreover, because we create our local mesh by extracting from part of the global model mesh, the relationship between the local and global meshes is straightforward, so we can easily create a projection of the Jacobian matrix between global and local meshes and rapidly construct the global Jacobian matrix for 3D EM inversions. After formulating the boundary value problem based on the finite-element method, we verify the accuracy of our modeling algorithm by checking against the semianalytical solution for a homogeneous half-space model, and we test our inversion algorithm by running inversions on synthetic and survey data collected over Vesterålen, Norway. The numerical experiments demonstrate that our method can model the AEM responses at high accuracy and recover the subsurface main resistivity structures from synthetic and field data.
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基于小波的频域机载电磁数据 3D 反演
影响因子：
2.8
作者：
Yunhe Liu;Colin G. Farquharson;Changchun Yin;Vikas C. Branwal
通讯作者：
Vikas C. Branwal
影响因子：
3.3
作者：
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通讯作者：
Dikun Yang;D. Oldenburg
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影响因子：
3.3
作者：
Changchun Yin;Bo Zhang;Yunhe Liu;Jing Cai
通讯作者：
Jing Cai
DOI：
10.1190/1.2792464
发表时间：
2007
期刊：
Seg Technical Program Expanded Abstracts
影响因子：
--
作者：
L. Cox;M. Zhdanov
通讯作者：
L. Cox;M. Zhdanov
影响因子：
2.6
作者：
E. Auken;A. Christiansen;B. Jacobsen;N. Foged;K. Sørensen
通讯作者：
E. Auken;A. Christiansen;B. Jacobsen;N. Foged;K. Sørensen