Open AccessA note on the isostatic compensation and origin of King's Trough
Author(s) -
Louden Keith E.
Publication year - 1983
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.1983.tb01941.x
Subject(s) - geology , trough (economics) , lithosphere , mantle (geology) , plate tectonics , crust , seismology , ridge , gravity anomaly , flank , seafloor spreading , paleontology , tectonics , sociology , oil field , anthropology , economics , macroeconomics
Summary. The spectral analysis of a 550 km long ship‐board gravity and topography profile, across the central part of King's Trough in the north‐eastern Atlantic Ocean, shows that the topography is regionally compensated on lithosphere older than 20Myr. This feature, with its enigmatic trend oblique to that of the mid‐Atlantic ridge, therefore dates from no earlier than the late Oligocene and was formed by intra‐plate activity. Such a constraint to its age agrees with the recent analysis of geological samples taken on the northern flank of the trough close to the position of the profile. It is not consistent with previous suggestions that King's Trough was created either by the rotations of the Iberian plate to form the Pyrenees or by a readjustment in the strike of the mid‐Atlantic ridge. Furthermore, this analysis shows no evidence for either thin crust or high density mantle under the trough. There is no structural evidence to suggest that it formed as part of a compressional boundary.