Delineation of layer boundaries from smooth models obtained from the geoelectrical sounding data inversion

• Autorzy: Israil M.
• Języki publikacji: EN

Abstrakty

EN

Two techniques have been presented for the delineation of boundaries from smooth models obtained by smooth inversion techniques of geoelectrical sounding data, such as straightforward inversion scheme, Occam’s and Zohdy’s methods. The smooth model consists of a large number of equally spaced layers, wherein the real geological boundaries are missing. The techniques proposed here suppress the geologically irrelevant boundaries and support the real structural boundaries present in the geoelectrical data. In the first technique, solution of linear inverse problem is improved iteratively through weighted minimum norm inverse, the weight being taken from the current solution. The technique is referred as Iterative Straightfor-ward Inversion Scheme. The second method is analytical, based on the application of smoothing filter, referred in the literature as edge-preserving smoothing. A few examples of theoretical magnetotelluric, dc resistivity and field sounding data have been presented to demonstrate the capabilities of the techniques. The methodologies also reduce the conspicuous oscillations in the smooth solutions caused by the con-version of sharp boundaries to the smooth ones.

Słowa kluczowe

EN

iterative straightforward inversion; dc resistivity; magnetotellurics

• Wydawca: Instytut Geofizyki PAN ; Springer
• Czasopismo: Acta Geophysica
• Rocznik: 2006
• Tom: Vol. 54, no. 2
• Strony: 126--141

Twórcy

autor

Israil M.

• Department of Earth Sciences, Indian Institute of Technology Roorkee Roorkee-247667, India,

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