|Blocks||ER 3B/4B (award pending Govt approval)|
Block 3B/4B, located between 120-250kms offshore western South Africa, covers an area of 17,581km² and lies in water depths ranging from 300-2500m. The 3B/4B licence was previously held by BHP Billiton who acquired a 10,000km² GeoStreamer 3D survey in 2012, which Azinam plans to reprocess. During the same year, Shell acquired a further 8,000km² of 3D to the north of the 3B/4B, which is on strike with the BHP survey. 1,400kms of multi vintage 2D seismic data also spans the licence.
Historically, a considerable number of wells (32) were drilled in the shallow water western margin of South Africa, to the east of 3B/4B. These wells were predominantly targeting the Mid-Cretaceous Aptian source play. Most of these wells encountered gas or gas shows due to the considerable depth of burial of the Aptian source. Oil was found along the margin, within the AJ-1 well, but this oil was typed to a syn-rift lacustrine source unit, and its extent is believed to be localised. Encouragingly, further offshore, in the area surrounding 3B/4B, overburden thicknesses decrease and the more laterally extensive Aptian source is prognosed to be oil prone. This has resulted in a considerable resurgence of industry interest by major players such as Shell, Kosmos, Total and Anadarko.
Substantial quantities of Late Cretaceous sands, sourced by the Orange River, have been encountered in wells offshore South Africa and are a major focus for reservoir investigation. Seismic has allowed these deposits to be identified and indicates significant reservoir potential to be present in the form of turbidites and reworked sands. These can often be trapped within rollover and toe-thrust structures. Carbonate deposits, associated with outer-highs, have also been encountered and are becoming more of a focus for upcoming exploration.
Wolf, formerly Aardwolf, is one of the key prospects on block 3B/4B. It comprises a significant 110km2 4-way structural closure of a Barremian/Aptian aged carbonate build-up. The Moosehead-1 well, drilled by HRT in the Namibian part of the Orange Basin, demonstrated the potential for this Lower Cretaceous carbonate play by penetrating 100m of Barremian limestone deposited above the marginal ridge. In addition to Aardwolf, significant prospects also exist through all stratigraphic levels, from the Barremian to the Maastrichtian, with both structural and stratigraphic trapping types being considered.