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arXiv · 1602.03262

Interface-Flattening Transform for EM Field Modeling in Tilted, Cylindrically-Stratified Geophysical Media

Kamalesh Sainath·Fernando L. Teixeira
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Abstract

We propose and investigate an "interface-flattening" transformation, hinging upon Transformation Optics (T.O.) techniques, to facilitate the rigorous analysis of electromagnetic (EM) fields radiated by sources embedded in tilted, cylindrically-layered geophysical media. Our method addresses the major challenge in such problems of appropriately approximating the domain boundaries in the computational model while, in a full-wave manner, predicting the effects of tilting in the layers. When incorporated into standard pseudo-analytical algorithms, moreover, the proposed method is quite robust, as it is not limited by absorption, anisotropy, and/or eccentering profile of the cylindrical geophysical formations, nor is it limited by the radiation frequency. These attributes of the proposed method are in contrast to past analysis methods for tilted-layer media that often place limitations on the source and medium characteristics. Through analytical derivations as well as a preliminary numerical investigation, we analyze and discuss the method's strengths and limitations.

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Kamalesh Sainath, Fernando L. Teixeira. 2016-02-16. Interface-Flattening Transform for EM Field Modeling in Tilted, Cylindrically-Stratified Geophysical Media. https://doi.org/10.1109/lawp.2014.2379677

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