The Influence of Topography on Subaqueous Sediment Gravity Flows and the Resultant Deposits: Examples From Deep-water Systems in Offshore Morocco and Offshore Trinidad

Abstract

Submarine topography has a fundamental control on the movement of sediment gravity flows as well as the distribution, morphology, and internal heterogeneity of resultant overlying, healing-phase, deep-water reservoirs. Some of the most complex deep-water topography is generated through both destructive and constructive mass transport processes. A series of forward numerical models of sedimentary processes using Sedflux software have been constructed over high resolution mass transport complexes (MTCs) top paleobathymetric surfaces mapped from 3D seismic data in offshore western Morocco and offshore eastern Trinidad. The MTC along Morocco's margin is characterized by large, extant rafted blocks and a flow-perpendicular fabric. The MTC along Trinidad's margin is characterized by muddier, plastic flows and isolated extrusive diapiric buttresses. In addition, Morocco's margin is a dry, northern latitude margin that lacks major river inputs, while Trinidad's margin is an equatorial, wet climate that is fed by the Orinoco River and delta. These models quantitatively delineate the interaction of healing-phase gravity flows on the tops of two very different topographies and provide insights into healing-phase reservoir distribution and stratigraphic trap development. Slopes roughness, curvatures, and surface shapes are measured and quantified relative to input points to quantify depositional surface character. A variety of sediment gravity flow types have been input and the resultant interval assessed for thickness and distribution relative to key topography parameters. Mathematical relationships are to be analyzed and compared with seismic data interpretation of healing-phase interval character, toward an improved model of gravity sedimentation and topography interactions.

AAPG Datapages/Search and Discovery Article #90291 ©2017 AAPG Annual Convention and Exhibition, Houston, Texas, April 2-5, 2017