Seismic Stratigraphy and Hydrocarbon Prospectivity in the Northern Sector of the North Falkland Basin, South Atlantic

Abstract

Analysis of 2D seismic reflection data north of the Falkland Islands, has delineated a series of discrete basins to the north of the prolific North Falkland Basin, which are termed here as the Northern sector of the North Falkland Basin (NNFB). Six regionally significant seismic reflectors have been interpreted within this data set, dividing the sedimentary fill into six tectono-stratigraphical packages, including: early syn-rift, late syn-rift, transitional phase, early post-rift, middle to late post-rift and an undifferentiated sag phase. Structural interpretation has led to the definition of four north-south orientated depocentres: (1) Eastern Graben, (2) Eastern Graben Splay (3) Western Graben splay and (4) the newly defined Phyllis Graben. A network of NW-SE and NE-SW trending faults controlled the development of these grabens through the syn-rift and into the late post-rift. Hydrocarbon discoveries to the south of this study area (e.g. Sea Lion, Isobel Deep and Liz) confirm a nearby working petroleum system. This study has identified various Direct Hydrocarbon Indicators, such as shallow amplitude brightening events; these may correspond to an extension of this petroleum system and active migration pathways. The main interval of hydrocarbon interest in the northern sector is likely to be vertically amalgamated stratigraphically trapped turbidite fans within the early post-rift interval. This paper also proposes a secondary fluvial structural syn-rift play, which has yet to be tested in this region.

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