唐山周围地区地磁短周期变化异常及深部电导率结构

<正> 对地下深部导电率结构的了解有助于认识地下深处的物质成分、状态、结构、温度等.陈伯舫(1974)曾利用地磁台站资料研究过渤海西岸的导电率结构,指出昌黎一带以南地下60km 处有一低电阻层,电导率约为20Ω·m.祁贵仲等(1981)曾收集渤海周围25个地磁台站的地磁短周期变化事件,分析了该区的地磁短周期变化的异常特征,并推断在渤海中部存在(?)地幔高导层的隆起.然而,由于地磁台站较少,台站的空间分布也不均匀,上述研究的结论仅仅是初步的认识.

Thre-dimensional topographic responses in MT using finite diference method

In this paper, the magnetotelluric response to 3-D earth topography was studied using the finite difference method for rectangular cells. Three numerical modeling calculations were carried out; the results indicate that the finite difference method is applicable to the magnetotelluric problem in estimating the 3-D topographic responses.