Open AccessThe Sinking of Rockall Plateau
Author(s) -
Matthews D. H.,
Smith S. G.
Publication year - 1971
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.1971.tb01839.x
Subject(s) - geology , crust , eclogite , continental margin , continental crust , structural basin , sedimentary basin , seismology , sedimentary rock , geodynamics , petrology , geomorphology , tectonics , geochemistry , subduction
Summary Intracontinental sedimentary basins and large blocks at the inactive continental margins have sunk but remained in isostatic equilibrium. Seismic refraction results show that the continental crust has been thinned. How? Solution of this problem is an objective of the Geodynamics project. Two solutions have been suggested: either that the basaltic lower crust inverts to eclogite or that the crust thins by creep of its warm lower parts towards the rifted margin. We have used seismic reflection profiles across Hatton‐Rockall Basin where the sinking history is known from JOIDES drilling to try to choose; inversion to eclogite implies only faulting at the margins of the basin whereas creep implies normal faulting of the upper crust with stretching of the sedimentary cover. Our profiles showed faults only at the edge of the basin but we are unable to be sure that they do not show stretching of the sediments. We can draw no firm conclusion.