Open AccessDeep crustal geoelectric structure beneath the Northumberland Basin
Author(s) -
Beamish David
Publication year - 1986
Publication title -
geophysical journal of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.302
H-Index - 168
eISSN - 1365-246X
pISSN - 0016-8009
DOI - 10.1111/j.1365-246x.1986.tb04374.x
Subject(s) - geology , magnetotellurics , structural basin , seismology , inversion (geology) , submarine pipeline , geophysics , geomorphology , electrical resistivity and conductivity , oceanography , electrical engineering , engineering
Summary. In terms of lateral variations in conductivity structure, the southern Southern Uplands and Northumberland Basin are characterized by a region of attenuated vertical magnetic fields with small spatial gradients reflecting the presence of a substantial conducting zone. Five magnetotelluric data sets from the region have been analysed to provide accurate and unbiased estimates of the impedance tensor. The response data are used to investigate the deep geoelectric crustal structure of the region. Three appropriate sets of response data have been subjected to two construction algorithms for 1‐D inversion. The geoelectric profiles recovered identify a deep crustal conducting zone underlying the Northumberland Basin. The zone, modelled as a layered structure, dips steeply from mid‐crustal depths underneath the Northumberland Basin to lower crustal depths to the NW. The structure thus correlates, in location and geometry, with a deep crustal reflecting wedge detected offshore by a deep seismic reflection profile.