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http://dx.doi.org/10.5467/JKESS.2007.28.2.227

Electrical Anisotropy of the Okchon Belt Inferred from Magnetotelluric Data  

Lee, Choon-Ki (Department Earth Science Education, Seoul National University)
Lee, Heui-Soon (Department Science Education, Gyeongin National University of Education)
Kwon, Byung-Doo (Department Earth Science Education, Seoul National University)
Cho, In-Ky (Department Geophysics, Kangwon National University)
Oh, Seok-Hoon (Department Geosystem Engineering, Kangwon National University)
Song, Yoon-Ho (Geothermal Resources Group, Korea Institute of Geoscience and Mineral Resources)
Lee, Tae-Jong (Geothermal Resources Group, Korea Institute of Geoscience and Mineral Resources)
Publication Information
Journal of the Korean earth science society / v.28, no.2, 2007 , pp. 227-239 More about this Journal
Abstract
The MT data at the Okchon Belt show peculiar phase responses exceeding $90^{\circ}$. A reasonable explanation is that those responses are due to an electrical anisotropy structure which is composed of a narrow anisotropic block and an anisotropic layer. Considering the dominant anisotropic strikes of the block (NE-trend) and the layer (NW-trend) inferred from the MT data, if existing, the electrical anisotropy in the Okchon Belt was probably produced by the deformations in the pre-Jurassic period, since the NE-trending shearing or thrusting should create alternating bands of metamorphic rocks and fractures with NE-trending. Correlation of the structural strike of 2-D block with the latest EW-trending deformation events demonstrates that the geometrical structure of the anisotropic block was formed by the latest Daebo and Bulgugsa orogeny.
Keywords
electrical anisotropy; magnetotellurics; Okchon Belt; phases exceeding $90^{\circ}$;
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Times Cited By KSCI : 1  (Citation Analysis)
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