Published:January 01, 1995
1995. "Bredasdorp Basin", Sequence Stratigraphy in Offshore South African Divergent Basins: An Atlas on Exploration for Cretaceous Lowstand Traps by Soekor (Pty) Ltd., L. F. Brown, Jr., J. M. Benson, G. J. Brink, S. Doherty, A. Jollands, E. H. A. Jungslager, J. H. G. Keenan, A. Muntingh, N. J. S. van Wyk, G. J. Brink, N. J. S. van Wyk, L. F. Brown, Jr., K. R Barton, K. J Bate, S. R Carney, A. A. Fraser, N. Fraser, H. J. Gouws, M. G. Guest, K. A. Kitchin, H. W. Pferdekämper, J. Turner, V. H. Valicenti, G. W. J. Beamish, D. S. Broad, P. J. Buck, P. L. A. Burden, C. P. N. Davies, J. Fouché, C. E. Gilbert, K. Hodges, J. J. Maier, S. P. Petrie, S. H. Robson, J. Roux, G. J. Smit, J. Turner, V. H. Valicenti, D. Van Der Spuy, T. Webb, S. J. Winters, H. T. Buhrmann, R. D. P. Noble, P. J. Strauss
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Bredasdorp Basin covers approximately 18,000 km 2 beneath the Indian Ocean along the southern coast of South Africa, southwest of Mossel Bay (Figures 1, 71). The basin is filled with Upper Jurassic and Lower Cretaceous (lower Neocomian) synrift continental and marine strata and postrift Cretaceous and Cenozoic divergent margin rocks, as illustrated in Figures 9, 10, and 72. The basin is bounded on the west and southwest by the Agulhas Arch and on the northeast by the Infanta Arch. The Bredasdorp Basin opens southeastward to connect with the Southern Outeniqua Basin, which is terminated on the southeast by the Agulhas-Falkland Fracture Zone (Figure 73). Reactivated rift faults are prominent along the margin of the Agulhas Arch, and minor faults define the northeastern margin of the Infanta Arch.
The first exploratory borehole drilled in the Bredasdorp Basin during 1970 by Soekor (Pty) Ltd. was located on the northern flank of the basin. The initial test encountered subcommercial gas and condensate in lower shoreface sandstones within the drift succession. This first wildcat borehole did not intersect synrift reservoirs beneath the drift onset unconformity. A second borehole, drilled on the northern flank of the basin in 1972, intersected porous synrift coastal marine sandstones just below drift onset unconformity 1At1 (126 Ma). Postrift reservoirs in the second wildcat were absent, but the borehole intersected rich, immature source rocks of Aptian age.
During the 1970s, Soekor's exploration continued to focus principally on the synrift succession containing shallow marine sandstones just below the drift onset unconformity
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Sequence Stratigraphy in Offshore South African Divergent Basins: An Atlas on Exploration for Cretaceous Lowstand Traps by Soekor (Pty) Ltd.
“Sequence Stratigraphy in Offshore South African Divergent Basins” is the result of an offshore exploration and drilling program by Soekor (Pty) Ltd in the Republic of South Africa beginning in 1987. Seismic stratigraphic data and borehole information were incorporated and released in what was one of the first detailed and comprehensive published examples of the new field of sequence stratigraphy. The project was conducted over a South African offshore area of 175,000 km2, in the Pletmos, Bredasdorp, and Orange basins, which are examples of divergent basins associated with the breakup of Gondwana. Thirty-four third-order Cretaceous sequences between 126 and 67 Ma were recognized and correlated. The book is published in an oversized 11” × 24” landscape format, which works well for the numerous seismic lines and cross sections in this heavily illustrated volume. Each basin is examined in detail, including discussion of the tectonic, paleogeographic, and depositional settings, and the sequence stratigraphy based in large part on regional seismic interpretation. The application of the sequence stratigraphic interpretations to generation of petroleum prospects and evaluation of drilling results is the end result, provided in a manner that is far more open and enlightening than is the case for typical petroleum industry publications.