Along-Strike Sediment Transport is an Underappreciated Control on the Pleistocene Sedimentary Record Offshore East Coast Trinidad
We describe the Pleistocene source to sink marine depositional systems of Trinidad using a sequence stratigraphic framework to characterize the progradation and/or retrogradation of the margin through time. We use ∼ 9000 km2 of 3D seismic data and 10, 000 km of 2D seismic data, combined with well penetrations and bathymetry data to examine the role of dip parallel versus strike parallel sediment transport systems. Attribute extractions on the seafloor and key horizons, as well as regional transects traversing the margin, allow us to identify and study the properties of sediment transport pathways including submarine channel systems. We propose that during sea level high stand conditions, along-strike sediment transport systems which are driven by the north directed Guyana Current, dominate the shelf environment and are responsible for the movement of sediment from the South American margin in the south, to the Columbus Basin shelf and subsequently into the Darien, Barbados and Tobago Basins to the north. During low stand sea level conditions the margin is dominated by downdip transport of sediments from the Columbus Basin shelf to the deep basin, through a series of downdip oriented channels which range from ∼ 0.5 to 4 km in width and are concentrated in synclinal axes that are approximately parallel to depositional dip. An understanding of the controls on changing patterns of sediment distribution along a margin has implications for predicting the location of prospective reservoirs horizons in deep marine basins.
AAPG Datapages/Search and Discovery Article #90189 © 2014 AAPG Annual Convention and Exhibition, Houston, Texas, USA, April 6–9, 2014