Abstract
Abstract We carried out a magnetotelluric (MT) survey along a profile crossing the Median Tectonic Line (MTL) in western Shikoku, Japan. The MTL is a terrane boundary that formed during the Cretaceous between the Sanbagawa belt, consisting of high pressure/temperature (P/T) metamorphic rocks, and the Ryoke belt of granites and low P/T metamorphic rocks. The MT image shows a zone of remarkably low resistivity, dipping northward at 40°, at the surface coincides with the surface trace of the MTL. The low-resistivity zone probably corresponds to a fluid-filled damaged zone of porous media composed of clay minerals and cracked rocks, formed by repeated faulting of the MTL since Late Cretaceous time. The calculated maximum porosity of the damaged zone is 7.1%, which is clearly higher than that of the non-damaged crystalline rocks.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.