College of Earth Sciences, Guilin University of Technology

高密度电法是一种适用性广泛的电阻率勘探方法，拥有多种电极排列装置选择。不同装置由于电极分布方式的差异，在针对不同地质目标和测区环境时往往表现出明显不同的探测能力。为探究各排列装置的特点及其适用情况，推导了2.5D电位的变分问题，采用Delaunay三角化算法实现了非结构化网格剖分，进而实现了有限元正演模拟。结合实践，对常见地质情况进行建模，分别使用温纳α、温纳β、施伦贝谢尔、偶极−偶极4种装置开展正反演对比研究。研究发现：(1) 在探测未知区域单个异常体时，温纳β、施伦贝谢尔2种排列的效果更好；(2) 在探测相邻较近的多个异常体时，应优先采用具有更高水平分辨率的施伦贝谢尔和偶极−偶极排列；(3) 对于低阻破碎带的勘探，温纳β和偶极−偶极排列更为适用；(4) 当地层具有较好分层界限时，4种排列均可体现良好的分层效果。因此，高密度电法勘探实践中应综合考虑不同排列装置的特点，根据具体情况选用合适的多种排列方式进行测量，并对采集数据进行综合对比分析，以获得更为准确的解释结果。

Multi-electrode resistivity method is equipped with various electrode array configurations. Due to their different electrode arrangements, various electrode array configurations tend to exhibit significantly varying detection effects under different survey environments. Hence, to achieve satisfactory detection effects using high-resolution electrical resistivity tomography, it is necessary to explore the strategy for choosing appropriate array configurations targeting different objects in practical work. Given the high applicability of the method, its forward and inversion calculations remain a critical task. Based on the differential equations to be satisfied by the point source potential in a three-dimensional structure, this study derived the variational problem to be satisfied by the 2.5D potential and conducted the unstructured gridding using the Delaunay triangulation algorithm, thus achieving finite-element forward modeling. By combining practical applications, this study designed common geological models and performed forward and inverse calculations using Wenner $alpha $, Wenner $beta $, Schlumberger, and dipole-dipole arrays, analyzing their detection effectiveness in different environments. Key findings are as follows: (1) For the detection of isolated anomalous bodies in an unknown area, the Wenner $beta $ and Schlumberger configurations, determined by considering the accuracy and efficiency, can yield better detection effects. (2) The Schlumberger and dipole-dipole configurations exhibit higher horizontal resolution and can distinguish multiple anomalous bodies nearby. (3) For the detection of low-resistivity fractured zones, the Wenner $beta $ and dipole-dipole configurations enjoy better performance. (4) For strata with distinct boundaries, the Wenner $alpha $, Wenner $beta $, Schlumberger, and dipole-dipole configurations can all yield encouraging detection results. Therefore, for data collection using high-resolution electrical resistivity tomography, it is necessary to choose multiple array configurations and conduct comprehensive comparisons and interpretations of the forward and inverse modeling results.

国家自然科学基金面上项目(42274182)；广西自然科学基金项目(2023GXNSFDA026055)；广西高校中青年教师科研基础能力提升项目(2022KY0251)

赵荣春，吕玉增，张智，等. 基于2.5D有限元的高密度电法不同装置勘探效果研究[J]. 煤田地质与勘探，2024，52(4)：1−9.

ZHAO Rongchun，LYU Yuzeng，ZHANG Zhi，et al. Exploring the detection performance of different array configurations for Multi-electrode resistivity method tomography using a 2.5D finite element method[J]. Coal Geology & Exploration，2024，52(4)：1−9.