Tullow Oil has announced updates on several onshore projects in Kenya, including the Expir-1 exploration, Engomo-1 exploration, the Ngamia and Amosing appraisal wells, as well as the South Lokichar Basin 3D seismic.
The Epir-1 exploration well is located in block 10BB in the North Kerio Basin, a separate sub-basin from that tested by the Kodos-1 well, 25 km to the southwest. While not a discovery, the well encountered oil and wet gas shows over a 100-m interval of non-reservoir quality rocks, demonstrating a working petroleum system in this lacustrine sub-basin. Further exploration activities will be considered in the North Kerio Basin following analysis and integration of data collected from the well.
The Weatherford 804 rig drilled the Epir-1 well to a final depth of 3,057 m. The well will be plugged and abandoned, after which the rig will move to the Ekales-2 location in the South Lokichar Basin. There, the rig will conduct appraisal of the discovery made by the Ekales-1 well. The well will target reservoirs in a separate fault block to the east of the discovery well, further away from the basin-bounding fault.
“The Epir-1 wildcat well proved the existence of a working oil system in the North Kerio Basin, encouraging us to consider further exploration activities,” Exploration Director Angus McCoss said.
On the Engomo-1 well, SMP Drilling’s new SMP-106 rig has commenced drilling operations. This well is the first test of the prospective North Turkana Basin in Kenya Block 10BA. This onshore prospect is to the west of Lake Turkana, where numerous naturally occurring oil slicks and seeps have been observed. A result is expected in early March 2015.
Tullow also has completed drilling the Ngamia-5, Ngamia-6 and Amosing-3 appraisal wells, using the PR Marriott 46 rig. Both Ngamia wells were drilled from the Ngamia-1 discovery well pad. Ngamia-5 was drilled to a final depth of 2,317 m and was deviated approximately 500 m northeast of Ngamia-1, encountering 160-200 m of net oil pay. Ngamia-6 was drilled to a final depth of 2,480 m and was deviated approximately 800 m north of Ngamia-1, encountering up to 135 m of net oil pay. Both wells have been suspended and remain available for use in an extended well test program that will commence in Q2 2015.
The Amosing-3 well in Block 10BB continued the successful appraisal of the Amosing oil field. The well was drilled approximately 1 km northwest of the Amosing-1 discovery well and encountered more than 107 m of net oil pay in good-quality reservoir sands. The well reached a final depth of 2,403 m and has been suspended for use in future appraisal and development activities. The PR Marriott 46 rig will now be moved to continue the appraisal of the Ngamia field, drilling the Ngamia-7 well to test the field’s eastern flank.
Acquisition of the large 951-sq-km 3D seismic survey has completed over the series of significant oil discoveries in the western basin-bounding fault play of the South Lokichar Basin. The fast-track processed data is already being used in the south of the basin, while the remainder of the survey will be available for seismic interpretation by the end of Q1 2015. Initial evaluation of the 3D seismic data indicates significantly improved structural and stratigraphic definition, and additional prospect not evident on the previous 2D seismic data. In addition, the partnership has acquired over 1,100 m of core samples from the South Lokichar Basin wells, and an ongoing program of detailed core analysis will provide results from Q1 2015 onwards to measure oil saturation and assess recovery factors of the reservoir sands.
“Continued success in the appraisal of the Ngamia and Amosing oil fields is highly encouraging as we continue with development studies for the South Lokichar Basin,” Mr McCoss said.
Tullow Operates Blocks 10BB, 13T and 10BA with 50% equity and is partnered by Africa Oil Corp, also with 50%.