Sediment Dispersal Patterns Within Linked Mini Basins: From Analysis of the Interplay Between Clastic Sedimentation and Salt Tectonics in the Lower Congo Basin, Deepwater Angola

Katerina Garyfalou and David Johnstone
PGS Reservoir, Maidenhead, United Kingdom

We present an integrated approach to the study of sediment dispersal patterns within salt induced mini-basins, utilizing a merged 3D seismic dataset and well data from the deepwater region in the Lower Congo Basin, Angola.

An investigation into the mini-basins in this region has shown that the high topographic relief on the palaeo-seafloor had a profound influence on both the type and distribution of the depositional systems infilling the basin. The mini basins were filled by a variety of sediment gravity flow deposits including channel systems, mass transport deposits and hemipelagic material, all of which have a distinct seismic facies. These seismic facies have been classified and used to understand the complex interplay which exists both within, and between, the linked mini basins. The work has shown that the movement of the salt reconfigures the morphology of the receiving basin and also acts as one of the main trigger mechanisms for mass wasting events, which in themselves modify the morphology of the receiving basin.

By understanding the structural evolution of this region we can show how this affects the type and the distribution of mass transport deposits observed within the mini basins. The affect that these deposits have on the subsequent sediment deposition, is key to understanding the distribution of potential reservoir units.

AAPG International Conference and Exhibition, Cape Town, South Africa 2008 © AAPG Search and Discovery