MODELING STUDY ON MULTIPLE THIN-PLATE CONDUCTORS BASED ON SURFACE-HOLE TRANSIENT ELECTROMAGNETIC ANOMALY RESPONSES
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摘要:
地-井瞬变电磁法(SHTEM)是指场源在地面激发, 接收线圈在钻井中观测瞬变响应, 用以勘查深部矿产资源的勘探方法. 从等效涡流环方法原理出发, 计算了等效涡流环与Rx之间的互感系数以及感应电压. 通过建立组合薄板导体的数学模型, 计算模拟地下存在多个薄板状良导体组合情况下的起响应叠加场, 以研究组合导体的地-井瞬变电磁异常响应, 并分析这些异常响应的特征及规律. 认为钻孔在距离多个组合薄板状矿体较近的情况下, 通过地-井瞬变电磁测量能够进行分辨.
Abstract:The surface-hole transient electromagnetic method (SHTEM) is used to explore deep mineral resources by which field source is excited on surface and transient responses are observed through receiving coil in borehole. The mutual inductance coefficient and induced voltage between equivalent eddy current ring and Rx are calculated based on the principle of equivalent eddy current ring method. By establishing a mathematic model of multiple thin-plate conductors, the response superimposed field is calculated and simulated under the condition that there are combinations of multiple thin conductive plates underground to study the surface-hole transient electromagnetic anomaly responses of multiple conductors and analyze their characteristics and rules. It is considered that multiple combinations of thin plate orebodies can be distinguished through SHTEM when they are close to the borehole.
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Key words:
- SHTEM /
- multiple conductor /
- conductive plate /
- equivalent eddy current
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