The Greater Etom Area (GEA): A New Phase of Exploration in the South Lokichar Basin, Turkana County, Northern Kenya

Abstract

East Africa is an integral part of the Tullow business. Tullow has been active for over ten years in the onshore rift basins of East Africa, which began with the opening of the Uganda Lake Albert Rift Basin in 2006 following the drilling of Mputa-1. We developed multiple sub-surface evaluation tools and an understanding on how rift success factors can combine during the drilling of the Lake Albert Basin that we then applied to the Tertiary rifts of Kenya. Extensive Full Tensor Gradiometry (FTG), seismic and drilling has taken place over the last five years in Kenya. This has established the South Lokichar basin as a significant oil basin with significant remaining exploration upside. Up until 2015 exploration drilling in the South Lokichar utilized 2D seismic data. The acquisition of 3D seismic in the north and west of the basin has allowed an improved definition of the structural framework and highlighted additional exploration potential. The Etom-2 well spud in November 2015 highlights the value of this 3D seismic in complex structural settings. Etom-1 was planned and drilled on 2D seismic and encountered 10 m of oil pay. Subsequent re-mapping based upon the 3D seismic revealed that the Etom structure was more complicated than originally interpreted and that Etom-1 had drilled into a collapse graben and not tested the structural crest of the field. Etom-2 targeted the up-thrown northern fault block which was not penetrated by the Etom-1 well and encountered 102 m of oil pay. The northern part of the South Lokichar basin is structurally complex and the 3D seismic provided the required detail to highlight that Etom-1 hadn't properly tested the Etom structure. Further mapping of the 3D seismic in the area around Etom-2 has identified multiple follow-up prospects that could be part of a new play domain in the northern part of the South Lokichar Basin. These targets are the focus for Exploration drilling that is due to commence in Q4 2016.

AAPG Datapages/Search and Discovery Article #90267 ©2016 AAPG/SPE Africa Energy and Technology Conference, Nairobi City, Kenya, December 5-7, 2016