Controlled Source Magnetotellurics with Vector Measurement Using Electric and Magnetic Sources

전기장 또는 자기장 송신원을 이용한 벡터 CSMT

The horizontal magnetic dipole as well as electrical dipole was adopted as a source to compute one-dimensional electromagnetic field behavior in controlled source magnetotellurics. he Cagniard impedances due to horizontal magnetic dipole source, especially phases, showed better frequency characteristics than those due to electric one. The magnetic dipole is inferior to the electric dipole in the point of relatively weak transmitting power at low frequency. But considering high resistivity charateristics of Korean geology, the magnetic dipole source is recommended for the survey up to depth of 500 m. A vector CSMT was introduced to get more reliable data in the area of two- or three-dimensional structures. A software and interpretation technique using polarization ellipses were developed. The technique was tested by synthetic data, which provided theoretical basis of the methodology. Although CSMT has inevitable limitation of investigation depth due to practically possible source-receiver separation, we proposed to use the technique developed in this paper where MT is not available, for example, in extremely noisy area or for shallow target.