As of June 2020, it is believed that Heritage Oil plc was still seeking partners for the Rukwa Basin licence that includes the Ruwa South block. The contract covers 4,395 sq km over the Ruwa Graben, Western Branch of the East African Rift System. Heritage is the sole participant in the licence.  Heritage had plan to drill its first new-field wildcat well in November 2018. The Hammerkop prospect will target a mean resource of 300 MMbo. Heritage Oil has identified in eight prospects that are analogous to the Ugandan discoveries based on a legacy 2,300 km of 2D seismic survey and a 600 km infill 2D seismic survey for a total unrisked mean prospective resources of 800 MMbl and 2.2 Tcf.   On 27 June 2016, scientific journals informed that a consortium formed by Helium One and two universities in the UK had discovered 54 Bbbl of helium in the southern part of the Rukwa Graben (within the Rukwa South Licence). The helium (and nitrogen) gas was sampled at surface, bubbling out of the ground. Researchers believe that the discovered helium field is a game changer for the future security of societyâs helium needs. Helium One informed previously that the helium was trapped in 27 leads defined by 2D seismic and supported by data from two legacy hydrocarbon exploration wells (see Background Information).   Background Information  Earlier exploration activity within the Rukwa Graben was conducted by Amoco in the mid-1980s with the acquisition of about 2,300 km of 2D seismic data and the drilling of two wells in 1987, Ivuna 1 (TD 2,316 m) and Galula 1 (TD 1,524 m). Both wells were plugged and abandoned as dry.  The Rukwa Production Sharing Agreement (including both Rukwa North and Rukwa South tracts) was awarded to Heritage between October and November 2011. The first exploration period was to last for four years.  Heritage completed reprocessing the legacy 2D seismic data and performed additional well data studies between 2012 and 2013.  The company acquired and processed 600 km of 2D (OBC and land) seismic data targeting the basin margins. Initial interpretation indicated that the main prospective region was located in the Rukwa South area, therefore in January 2014 Heritage relinquished the Rukwa North tract.  Rukwa Graben Geology  The Rukwa Basin is part of the East African Rift System, Western Branch. Bordered by strike-slip faults that are connected to those of Lake Tanganyika, the Rukwa is approximately 350 km long in a northwest-southeast direction and 30-60 km wide. It is partly covered by Lake Rukwa, a very shallow lake (up to 5 m deep), fed by the Songwe and Momba rivers from the south, the Kayu and Rungwe rivers from the north and the Lukwati River from the east. Three major stratigraphic units have been recognized, from oldest to youngest: the Karoo Supergroup (Permian-Triassic), the Red Sandstone Group (Jurassic-Cretaceous) and the Lake Beds (Late Miocene-Recent). The three units crop out along the margins of the sub-basin or are exposed in stream cuts. The recent rifting commenced around eight million years ago and the oldest rift-related deposits contain Upper Miocene palynomorphs and mammalian fossils.
Tanzania (East African Rift System, Western Branch) Rukwa Basin op. by HERITAGE (100%), Heritage Oil Plc Believed still seeking partners for the Rukwa Basin licence