The Deepwater Channels Migration and Evolution Under the Inference of Bottom Current in Offshore Mozambique, East Africa

Abstract

Channels are the most important reservoirs for deepwater oil and gas exploration. The channels have different characters with the inference of bottom current in offshore Mozambique. Here we use an integrated subsurface dataset, including high-resolution (~30 Hz) three-dimensional seismic-reflection data and well logs, to interpret the stratigraphic architecture and the evolution of a Miocene deepwater channel complex. The channel complex can be separated into three channel belts, each of them is about 2-5 km wide and hundreds of meters thick. Asymmetrical levee-overbank wedges bound the channel belt; the northern levee-overbank is much larger than the southern. The channel belts appear to migrate from north to south. Vigorous south-to-north-directed deepwater bottom currents might have influenced subsequent channel-belt evolution by dispersing relatively fine-grained portions both from sediment-gravity flows and the bottom currents to the northern levee-overbank wedge. The relatively large northern levee-overbank wedge might have promoted unidirectional channel-element migration to the south. The Mozambique continental margin therefore offers a unique opportunity to study the stratigraphic evolution of deepwater channels under the inference of bottom current. Moreover, active bottom-current processes potentially have a significant impact on reservoir architecture (channel-element stacking patterns) and quality (net-to-gross) in deepwater Mozambique and analogous settings.

AAPG Datapages/Search and Discovery Article #90350 © 2019 AAPG Annual Convention and Exhibition, San Antonio, Texas, May 19-22, 2019