Hatton Bank (northwest U.K.) continental margin structure

Autor: Martin Harold Phillips Bott, S. R. Fowler, A.N. Bowen, G.D. Spence, Mathias Joppen, Joanna Morgan, Penny Barton, C. Prestcott, Graham K. Westbrook, Robert S. White
Rok vydání: 1987
Předmět:
Zdroj: Geophysical Journal International. 89:265-272
ISSN: 1365-246X
0956-540X
DOI: 10.1111/j.1365-246x.1987.tb04418.x
Popis: Summary. The continent-ocean transition near Hatton Bank was studied using a dense grid of single-ship and two-ship multichannel seismic (mcs) profiles. Extensive oceanward dipping reflectors in a sequence of igneous rocks are developed in the upper crust across the entire margin. At the landward (shallowest) end the dipping reflectors overlie continental crust, while at the seaward end they are formed above oceanic crust. Beneath the central and lower part of the margin is a mid-crustal layer approximately 5 km thick that could be either stretched and thinned continental crust or maybe newly formed igneous crust generated at the same time as the dipping reflector sequence. Beneath this mid-crustal layer and above a well defined seismic Moho which rises from 27 km (continental end) to 15 km (oceanic end) across the margin, the present lower crust comprises a 10-15 km thick lens of material with a seismic velocity of 7.3 to 7.4 kds. We interpret the present lower crustal lens as underplated igneous rocks left after extraction of the extruded basaltic lavas. A considerable quantity of new material has been added to the crust under the rifted margin. The present Moho is a new boundary formed during creation of the margin and cannot, therefore, be used to determine the amount of thinning.
Databáze: OpenAIRE
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