TY - JOUR
T1 - Ridge-regression algorithm for gravity inversion of fault structures with variable density
AU - Chakravarthi, Vishnubhotla
AU - Sundararajan, Narasimman
N1 - Funding Information:
The authors record their sincere thanks to the assistant editor, Dr. Yonghe Sun, and the associate editors, Drs. Peirce and Dhananjay Ravat, for their very constructive suggestions and encouragement. The reviewers are acknowledged for their very useful suggestions to improve the presentation. Dr. V. P. Dimri, director, National Geophysical Research Institute, is sincerely thanked for according permission to publish this paper. The first author (VC) acknowledges the Council of Scientific and Industrial Research, Government of India, for granting financial assistance under the Young Scientist project. We also thank Drs. R. Srinivasan and T. R. K. Chetty for their constructive suggestions.
PY - 2004
Y1 - 2004
N2 - We derive an analytical expression for gravity anomalies of an inclined fault with density contrast decreasing parabolically with depth. The effect of the regional background, particularly the interference from neighboring sources of a fault structure, is ascribed by a polynomial equation. We have developed an inversion technique employing the ridge-regression iterative algorithm to infer the shape parameters of the fault structure, in addition to the effect of regional background. We demonstrate the validity of the proposed technique by inverting a gravity anomaly of a theoretical model, both with and without adding a regional background. The technique is insensitive to the effect of regional background. Two density-depth models of the Godavari subbasin in India are used in our interpretation of the gravity anomalies of the Ahiri-Cherla master fault. The interpreted results of a parabolic density model are found to be more geologically reasonable in comparison with the constant density model. The variations of the misfit function of the theoretical and observed gravity anomalies, the damping factor, and the shape parameters of the fault against the iteration number indicate the reliability of the interpretation.
AB - We derive an analytical expression for gravity anomalies of an inclined fault with density contrast decreasing parabolically with depth. The effect of the regional background, particularly the interference from neighboring sources of a fault structure, is ascribed by a polynomial equation. We have developed an inversion technique employing the ridge-regression iterative algorithm to infer the shape parameters of the fault structure, in addition to the effect of regional background. We demonstrate the validity of the proposed technique by inverting a gravity anomaly of a theoretical model, both with and without adding a regional background. The technique is insensitive to the effect of regional background. Two density-depth models of the Godavari subbasin in India are used in our interpretation of the gravity anomalies of the Ahiri-Cherla master fault. The interpreted results of a parabolic density model are found to be more geologically reasonable in comparison with the constant density model. The variations of the misfit function of the theoretical and observed gravity anomalies, the damping factor, and the shape parameters of the fault against the iteration number indicate the reliability of the interpretation.
UR - http://www.scopus.com/inward/record.url?scp=12144260810&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=12144260810&partnerID=8YFLogxK
U2 - 10.1190/1.1836814
DO - 10.1190/1.1836814
M3 - Article
AN - SCOPUS:12144260810
SN - 0016-8033
VL - 69
SP - 1394
EP - 1404
JO - Geophysics
JF - Geophysics
IS - 6
ER -