The inversion of subsurface geological structures is a crucial approach for gaining insights into the internal composition of the earth. In this paper, we propose a novel inversion method combining the nonsingular indirect boundary element method (IBEM) with the multistrategy particle swarm optimization (MSPSO) algorithm, tailored for accurately inverting 3D subsurface cavities. Leveraging the semi‐analytical nature of IBEM offers advantages such as dimensionality reduction, automatic fulfillment of radiation conditions at infinity, and high computational accuracy. Furthermore, to augment global optimization and local search capabilities, an MSPSO algorithm is introduced. Employing multiple optimization strategies enhances particle diversity, accelerates algorithm convergence, and mitigates the risk of local optima. Through the consideration of subsurface cavities with varying parameters, this method quickly identifies the approximate location of the cavity within a wide search range. The final results demonstrate that the proposed method can simultaneously and accurately invert the 3D spatial position, size, and orientation of the cavity.

中文翻译：

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应用于三维次表面腔反演的非奇异间接边界元法和多策略粒子群优化算法


地下地质结构的反演是深入了解地球内部成分的重要方法。在本文中，我们提出了一种新的反演方法，将非奇异间接边界元法 （IBEM） 与多策略粒子群优化 （MSPSO） 算法相结合，专为精确反演 3D 地下空腔而设计。利用 IBEM 的半分析特性，可以带来降维、自动满足无穷远处的辐射条件以及高计算精度等优势。此外，为了增强全局优化和本地搜索功能，引入了 MSPSO 算法。采用多种优化策略可以提高粒子多样性，加速算法收敛，并降低局部最优的风险。通过考虑具有不同参数的地下空腔，该方法在较宽的搜索范围内快速识别空腔的大致位置。最终结果表明，所提方法可以同时准确地反转空腔的三维空间位置、大小和方向。