HEDLEY, RICHARD and JOHN WARBURTON, LASMO PLC, 101 Bishopsgate, London, EC2M 3XH, England

Abstract: The Structural Evolution of the Tafelney Plateau, Offshore Morocco

The Tafelney Plateau is a 120km wide, pronounced bathymetric high, off the West Coast of Morocco. The high is the surface topographic expression of an underlying structural arch that has a tectonic history involving Mesozoic extension, Late Cretaceous inversion and finally Late Tertiary doming.

To the east of the Tafelney Plateau, the High Atlas Basin was inverted at the end of the Cretaceous, resulting in widespread development of large inversion anticlines along reactivated Mesozoic extensional faults. The effects of the inversion are clearly evident along the shelf margin in the near-shore area. Beyond the shelf they become masked by normal faults associated with the development of the Atlantic Passive Margin and by the presence of numerous salt diapirs and allochthonous salt layers extruded/intruded into stratigraphically younger sequences.

Late Tertiary regional doming of the Tafelney Plateau folded the Jurassic to Late Tertiary section into a broad E-W trending arch that shows many similar features to the nearby Conception Bank. Here, the sedimentary section above oceanic crust is folded into a broad N-S orientated anticline with a wavelength of 150km. Conception Bank forms the northern part of the Canary Island Volcanic Chain and is widely believed to owe its origin to underlying mantle hot-spot activity. Folding appears to be Neogene-Quaternary in age, which is consistent with the main phase of volcanic activity in the Canary Island archipelago.

AAPG Search and Discovery Article #90923@1999 International Conference and Exhibition, Birmingham, England