Hilary Clement Olson¹, John E. Damuth², Peter Thompson³, Graham Moss¹

(1) The University of Texas at Austin, Austin, TX
(2) University of Texas at Arlington, Arlington, TX
(3) Computational Biochronology, Plano, TX

ABSTRACT: Latest Quaternary Studies of Downslope Transport within a Stratigraphic Framework, Gulf of Mexico Intraslope Basins Area

Latest Quaternary sediments from over 90 piston cores in the Gulf of Mexico Intraslope Basins Region were analyzed to study the timing and sourcing of downslope transport during the most recent glacial and the current interglacial intervals. Stratigraphic control based on the G. menardii zonation of Ericson and Wollin (1968), planktonic foraminiferal markers and a pervasive ash bed coincident with the top of the "X" zone enables the comparison of depositional processes within a temporal framework between intraslope basins. Analysis of depositional processes within this stratigraphic framework suggests that the majority of downslope transport occurs during the glacial period ("Y" zone) of the studied interval, including sandy turbidites, sandy debris flows, muddy debris flows, and slumps. Furthermore, foraminiferal faunas document that some turbidites and mass-transport deposits of the "Y" zone are sourced from previously deposited interglacial sediments because they contain the planktonic foraminifera, G. flexuosa. The limited amount of downslope transport noted during the current interglacial ("Z" zone) consists of muddy mass-transport deposits.

AAPG Search and Discovery Article #90906©2001 AAPG Annual Convention, Denver, Colorado