ELECTRICAL-RESISTIVITY MODEL OF THE CRUST AND UPPER-MANTLE FROM A MAGNETOTELLURIC SURVEY THROUGH THE CENTRAL PYRENEES

被引:39
作者
POUS, J [1 ]
LEDO, J [1 ]
MARCUELLO, A [1 ]
DAIGNIERES, M [1 ]
机构
[1] UNIV MONTPELLIER 2,URA CNRS,F-34060 MONTPELLIER,FRANCE
关键词
ELECTRICAL RESISTIVITY; EBRO BASIN; LITHOSPHERE; MAGNETOTELLURICS; PYRENEES;
D O I
10.1111/j.1365-246X.1995.tb06436.x
中图分类号
P3 [地球物理学]; P59 [地球化学];
学科分类号
0708 ; 070902 ;
摘要
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 0.0128 s to 2000 s, 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.
引用
收藏
页码:750 / 762
页数:13
相关论文
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