Abstract Transient electromagnetic method (TEM) is often used in urban underground space exploration and field geological resource detection. Inversion is the most important step in data interpretation. Because of the volume effect of the TEM, the inversion results are usually multi-solvable. To reduce the multi-solvability of inversion, the constrained inversion of TEM has been studied using the least squares method. The inversion trials were performed using two three-layer theoretical geological models and one four-layer theoretical geological model. The results show that one-dimensional least squares constrained inversion is faster and more effective than unconstrained inversion. The induced electromotive force attenuation curves of the inversion model indicate that the same attenuation curve may be used for different geological conditions. Therefore, constrained inversion using known geological information can more accurately reflect the underground geological information.

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透射电镜一维约束反演研究及在采空区探测中的应用

摘要 瞬态电磁法(TEM)常用于城市地下空间勘探和野外地质资源检测。反演是数据解释中最重要的一步。由于 TEM 的体积效应，反演结果通常是多重可解的。为了降低反演的多重可解性，使用最小二乘法研究了TEM的约束反演。反演试验使用两个三层理论地质模型和一个四层理论地质模型进行。结果表明，一维最小二乘约束反演比无约束反演更快、更有效。反演模型的感应电动势衰减曲线表明，同一衰减曲线可用于不同的地质条件。