Premium
Role of deep crustal fluids in the genesis of intraplate earthquakes in the Kachchh region, northwestern India
Author(s) -
Pavan Kumar G.,
Mahesh P.,
Nagar Mehul,
Mahender E.,
Kumar Virendhar,
Mohan Kapil,
Ravi Kumar M.
Publication year - 2017
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1002/2017gl072936
Subject(s) - geology , intraplate earthquake , crust , seismology , magnetotellurics , rift , fault (geology) , mantle (geology) , volcanism , geophysics , petrology , tectonics , electrical resistivity and conductivity , engineering , electrical engineering
Fluids play a prominent role in the genesis of earthquakes, particularly in intraplate settings. In this study, we present evidence for a highly heterogeneous nature of electrical conductivity in the crust and uppermost mantle beneath the Kachchh rift basin of northwestern India, which is host to large, deadly intraplate earthquakes. We interpret our results of high conductive zones inferred from magnetotelluric and 3‐D local earthquake tomography investigations in terms of a fluid reservoir in the upper mantle. The South Wagad Fault (SWF) imaged as a near‐vertical north dipping low resistivity zone traversing the entire crust and an elongated south dipping conductor demarcating the North Wagad Fault (NWF) serve as conduits for fluid flow from the reservoir to the middle to lower crustal depths. Importantly, the epicentral zone of the 2001 main shock is characterized as a fluid saturated zone at the rooting of NWF onto the SWF.