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Electrical Conductance Map for Saurashtra Region, Gujarat, India


Affiliations
1 Indian Institute of Geomagnetism, Panvel, Navi Mumbai 410 218, India
 

In the present study, we have deployed 35 fluxgate magnetometers and 20 long-period magnetotelluric sites to derive the electrical conductivity distribution of Saurashtra region, Gujarat, India. Geomagnetic field variations (X-north–south, Y-east–west and Z-vertically downward components) recorded at the above sites are investigated to obtain single-station vertical field transfer functions. Maps of induction arrows suggest that the offshore basins are more conducting than inland basins of the region. Thin sheet modelling of the induction features suggests that the anomalous behaviour is strongly influenced by the offshore and shelf edge sedimentary basins that contain thick depo centres of Mesozoic sediments. Jamnagar, Ulva and Mesozoic sedimentary basins on land are also reflected as high conductivity anomalies that could be related to the presence of carbonate/shale sediments. Release of carbon (in the form of thin films) due to thermal activity of Reunion hotspot on carbonate rich sediments may give rise to high conductivity anomalies.

Keywords

Carbon Films, Induction Arrows, Thermal Activity, Thin Sheet Modelling.
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  • Electrical Conductance Map for Saurashtra Region, Gujarat, India

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Authors

P. V. Vijaya Kumar
Indian Institute of Geomagnetism, Panvel, Navi Mumbai 410 218, India
P. B. V. Subba Rao
Indian Institute of Geomagnetism, Panvel, Navi Mumbai 410 218, India
A. K. Singh
Indian Institute of Geomagnetism, Panvel, Navi Mumbai 410 218, India
C. K. Rao
Indian Institute of Geomagnetism, Panvel, Navi Mumbai 410 218, India

Abstract


In the present study, we have deployed 35 fluxgate magnetometers and 20 long-period magnetotelluric sites to derive the electrical conductivity distribution of Saurashtra region, Gujarat, India. Geomagnetic field variations (X-north–south, Y-east–west and Z-vertically downward components) recorded at the above sites are investigated to obtain single-station vertical field transfer functions. Maps of induction arrows suggest that the offshore basins are more conducting than inland basins of the region. Thin sheet modelling of the induction features suggests that the anomalous behaviour is strongly influenced by the offshore and shelf edge sedimentary basins that contain thick depo centres of Mesozoic sediments. Jamnagar, Ulva and Mesozoic sedimentary basins on land are also reflected as high conductivity anomalies that could be related to the presence of carbonate/shale sediments. Release of carbon (in the form of thin films) due to thermal activity of Reunion hotspot on carbonate rich sediments may give rise to high conductivity anomalies.

Keywords


Carbon Films, Induction Arrows, Thermal Activity, Thin Sheet Modelling.

References





DOI: https://doi.org/10.18520/cs%2Fv114%2Fi10%2F2175-2181