Processing and 1D inversion of magnetotelluric data from Dubti area in Tendaho geothermal field, Ethiopia

Abstract

Electromagnetic methods are one of the most effective geophysical methods in geothermal exploration. They enable imaging the subsurface conductivity. Magnetotelluric (MT) and transient electromagnetic methods (TEM) are the most successful methods in identifying geothermal resources prior to drilling. The MT method uses the natural source of the electromagnetic field to screen out the resistivity structure down to a depth of several kilometers, whereas TEM uses an artificial source field to image the near-surface resistivity variations down to a depth of around one kilometre. Data collected by these methods are processed. The processed data are used for a 1D Occam inversion to create a resistivity model. This report discusses the processing and inversion of magnetotelluric (MT) data from the Dubti area in Tendaho geothermal field, NE-Ethiopia. TEM soundings from the Krýsuvík area in SW-Iceland are used as an example of the processing and inversion of transient electromagnetic data.