South Africa - Inkaba.org

Sequence Stratigraphic Characterisation of Petroleum Reservoirs in
block 11B/12B of the Southern Outeniqua Basin, South Africa
E.Nformi 1 , P. Carey 2 ,
1. University of the Western Cape, South Africa, E-mail: 2801278@uwc.ac.za
2. University of the Western Cape, South Africa, E-mail: pcarey@uwc.ac.za
ABSTRACT
Deep water depositional systems are the one type of system that cannot be easily reached, observed and studied in
the modern environment, in contrast to other siliclastic and carbonate reservoir systems (Weimer and Slatt, 2004).
Going past conventional routes of exploration, this study uses the invaluable tool of sequence stratigraphy to
effectively prognose the huge, vast, unique and unexplored potential of the Southern Outeniqua Basin.
Using standard sequence stratigraphy techniques, including amongst others (seismic analysis/interpretation, cores,
and logs) and the Wheeler diagram, lithology constrains and time relationships between basin margin and basin
axis depositional packages is established.
This established relationship for the deepwater Southern Outeniqua Basin and the landward-adjacent Pletmos
Basin is hereby used in predicting the location of reservoirs in this frontier basin and thus prospectivity in the
undrilled areas by correlation (in time) with the landward-adjacent Pletmos sub-basin.
Seismic, log and core data analyses and interpretation have been used to match shallow water and deepwater
depositional packages thus predict reservoir location in the deepwater Southern Outeniqua basin. A close look at
systems tracts, their geometries and lithologies shows how sequence stratigraphy can be used to foretell reservoir
location and contents (Neal et al., 1993).
Sequence stratigraphy has proven and is proving successful in screening for reservoirs in frontier basins and the
Southern Outeniqua Basin hasn’t proven it wrong nor made the exception.
KEYWORDS: Sequence stratigraphy, Wheeler diagram, frontier basin, depositional package, deepwater
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