ReconAfrica is preparing to drill the Kavango West 2A appraisal well after natural gas and potential liquids flowed to the surface from a second zone at its Kavango West 1X discovery in northeastern Namibia, advancing the project from testing whether hydrocarbons can flow to determining the reservoir’s extent and connectivity.
The company said on Monday that vertical production testing at Kavango West 1X, or KW1X, has been completed after the uppermost zone of the Huttenberg formation flowed natural gas and potential liquids to surface immediately after perforation and before acid stimulation.
The result follows the previously announced flow of hydrocarbons to surface from the upper Elandshoek formation, meaning two of six zones of interest identified in KW1X have now demonstrated the ability to flow hydrocarbons to surface.
ReconAfrica is developing the discovery with BW Energy, which holds a 20% working interest, and the National Petroleum Corporation of Namibia, Namcor, which has a 10% carried working interest.
Horizontal test next at KW1X
The next stage will involve drilling an open-hole horizontal section of up to 1 000 metres through the upper Huttenberg formation to establish a representative flow rate and provide further information about the reservoir.
ReconAfrica said the vertical testing programme was designed primarily to establish whether hydrocarbons in the identified reservoir zones could flow to the surface, rather than to determine commercial flow rates.
Flow rates from the Huttenberg test were not measured because of previously disclosed equipment limitations, leaving the planned horizontal test as an important next step in determining how the discovery could perform under a well configuration better suited to the fractured carbonate reservoir.
The company said it has addressed the equipment issue for the horizontal programme by procuring additional equipment and changing the surface operations service provider.
Production samples containing natural gas and potential liquids have also been collected and sent to laboratories in the United States for compositional analysis, with results expected in the coming weeks.
ReconAfrica selected the Huttenberg formation for the first horizontal test after identifying 75 metres of pay from the original well-log analysis, matrix porosity between large natural fractures and the flow of gas and potential liquids to the surface.
The formation is also about 600 metres shallower than the Elandshoek, allowing the Jarvie-1 rig to target a longer horizontal section. An additional horizontal test in the upper Elandshoek remains an option.
ReconAfrica president and chief executive Brian Reinsborough said achieving hydrocarbon flow from the Huttenberg had met the primary objective of the vertical production testing programme.
“We are excited to report another critical milestone of the KW1X production test, which is achieving our primary objective of proving the flow of hydrocarbons to surface, this time from the uppermost zone of the Huttenberg formation,” he said.
“The vertical cased-hole phase of testing at KW1X is now complete and with the significant data and technical information gathered from this test, we have a high level of confidence moving forward with an open-hole horizontal production test in the Huttenberg formation.”
Kavango West 2A appraisal well being prepared.
While work continues at KW1X, ReconAfrica is advancing permitting and preparations for the Kavango West 2A, or KW2A, appraisal well, which is intended to test how far the reservoir extends and whether it is connected across the structure.
Once the KW1X horizontal production test is complete, ReconAfrica and its partners plan to move to KW2A, drill a horizontal well, and conduct another open-hole horizontal production test.
The appraisal well therefore represents the next stage in evaluating the Kavango West discovery after KW1X established the presence of hydrocarbons and subsequent production testing demonstrated that hydrocarbons from two zones could reach the surface.
ReconAfrica said confirming the KW1X results through a horizontal flow-rate test would provide information needed to support potential resource and reserve bookings and, eventually, a final investment decision.
“Confirming the KW1X results with a flow rate test on a horizontal sidetrack as soon as possible will ultimately support resource and reserve bookings and a final investment decision on this emerging Damara Fold Belt Play,” Reinsborough said.
The company said KW1X could also have implications beyond the individual discovery, with 22 structures mapped from existing seismic data across PEL 73 and the potential to identify additional structures through further seismic work.
Rig remains at Kavango West
The Jarvie-1 rig remains at the KW1X location and will be used to drill the planned horizontal sidetrack. Routine maintenance is underway while ReconAfrica waits for additional testing equipment to be shipped from the United States and for the necessary permit amendments before drilling resumes.
The company has procured two high-pressure pumps, a swabbing unit and supporting equipment for the next testing phase, while H2OIL has been contracted to conduct surface operations and provide additional equipment, including an appropriately sized separator. Halliburton will continue providing downhole equipment and services.
The horizontal test will be designed to intersect the natural fracture system within the reservoir over a substantially greater distance than the vertical well, allowing ReconAfrica to establish a flow rate and gather additional information on the discovery’s potential productivity.
The results will then determine the technical context for drilling the KW2A appraisal well as ReconAfrica, BW Energy and Namcor move from establishing hydrocarbon flow at KW1X to assessing the size and connectivity of the Kavango West discovery.
