CSAMT Data Processing with Source Effect and Static Corrections, Application of Occam's Inversion, and Its Application in Geothermal System

6th Asian Physics Symposium

Hamdi, H.^1 ; Qausar, A.M.^1 ; Srigutomo, W.^1

Physics of Earth and Complex System, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Indonesia^1

关键词: Artificial signals;    Electromagnetic soundings;    Geothermal systems;    Resistivity curves;    Resistivity modeling;    Spatial filtering techniques;    Subsurface conditions;    Transmitter and receiver;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/739/1/012057/pdf
DOI  :  10.1088/1742-6596/739/1/012057

来源: IOP

【 摘 要 】

Controlled source audio-frequency magnetotellurics (CSAMT) is a frequency-domain electromagnetic sounding technique which uses a fixed grounded dipole as an artificial signal source. Measurement of CSAMT with finite distance between transmitter and receiver caused a complex wave. The shifted of the electric field due to the static effect caused elevated resistivity curve up or down and affects the result of measurement. The objective of this study was to obtain data that have been corrected for source and static effects as to have the same characteristic as MT data which are assumed to exhibit plane wave properties. Corrected CSAMT data were inverted to reveal subsurface resistivity model. Source effect correction method was applied to eliminate the effect of the signal source and static effect was corrected by using spatial filtering technique. Inversion method that used in this study is the Occam's 2D Inversion. The results of inversion produces smooth models with a small misfit value, it means the model can describe subsurface conditions well. Based on the result of inversion was predicted measurement area is rock that has high permeability values with rich hot fluid.