Open AccessElectrical resistivity model of the crust and upper mantle from a magnetotelluric survey through the central Pyrenees
Author(s) -
Pous Jaume,
Ledo Juanjo,
Marcuello Alex,
Daignières Marc
Publication year - 1995
Publication title -
geophysical journal international
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.302
H-Index - 168
eISSN - 1365-246X
pISSN - 0956-540X
DOI - 10.1111/j.1365-246x.1995.tb06436.x
Subject(s) - magnetotellurics , geology , crust , seismology , subduction , structural basin , fault (geology) , partial melting , mantle (geology) , tectonics , geophysics , electrical resistivity and conductivity , geomorphology , electrical engineering , engineering
SUMMARY An MT profile which roughly coincides with the south side of the ECORS‐Pyrenees deep reflection seismic profile was made from the North Pyrenean zone through the central Pyrenees and Ebro basin. The periods recorded ranged from 0.0128s to 2000s. Analysis of MT data shows a 2‐D conductive structure. The strike direction of the structure is E‐W, parallel to the Pyrenean chain. Interpretation of the data includes geomagnetic transfer functions and is constrained by some relevant geometric crustal features observed in seismic data. Accordingly, a 2‐D resistivity cross‐section has been obtained. The most striking results are: (1) detection of subvertical conductors in the upper crust coinciding with major fault zones; (2) detection of a deep, high‐conductivity zone at the contact between the Iberian and the European plates, (3) the fact that the European plate is thicker and more resistive than the Iberian one. Interpretation of the deep high conductivities suggests the existence of partial melting in the Pyrenees related to the subduction of the Iberian plate beneath Europe.