Hydrocarbon Potential of the Walvis Basin, Offshore Namibia

Abstract

The Walvis Basin is one of four underexplored offshore passive margin basins in Namibia. These basins were formed during the Early Cretaceous continental break-up and subsequent opening of the South Atlantic Ocean, which started in the south and propagated northward, giving rise to the Orange, Luderitz, Walvis and Namibe Basins. The Orange Basin is the oldest and deepest offshore basin and borders the South African offshore margin to the south, while the Namibe is the youngest of the four basins and borders the Angolan margin to the north. The Namibe Basin has a closer affinity to the Southern Angolan Basins, which is different to the other three basins. There have only been two hydrocarbon discoveries made on the Namibian Margin namely, the Kudu Gas Field in the Orange Basin and the Wingat-1 discovery in the Walvis Basin. The Kudu Gas field is the only commercial discovery in Namibia, discovered in 1974 by Chevron and partners with a total Volume of about 1.3 tcf, which is sourced from the Barremian age Kudu Shales. Wingat-1 well was drilled by HRT Africa and partners in 2012 and a non-commercial discovery was announced in the same year. Wingat-1 was sourced by the Aptian Source Rock which is in the oil generating window within the Walvis Basin. There are three prominent source rocks in the Basin namely, the Cenomanian - Turonian, Aptian and Syn – Rift Source Rocks. The Cenomanian – Turonian is a widely distributed good quality source rock with an average 4% TOC and it is encountered by most wells drilled in the basin. The only potential risk for this source rock is its maturity. The Aptian Source Rock however, is a proven marine oil – prone source within the basin and was penetrated by both HRT’s Murombe and Wingat -1 wells. The Syn-rift section is observed on seismic but has never been penetrated by wells drilled in Namibia. The Walvis Basin area holds massive exploration targets, with good quality reservoirs at the Cenomanian and Santonian level. Several Cenomanian channel systems characterised by both structural and stratigraphic type traps have been mapped (Lower Cretaceous basin floor/slope fan systems)

AAPG Datapages/Search and Discovery Article #90332 © 2018 AAPG International Conference and Exhibition, Cape Town, South Africa, November 4-11, 2018