Tullow Oil announced Friday that the Enyenra-4A appraisal well, in the Deepwater Tano license offshore Ghana, has successfully encountered oil in very good quality sandstone reservoirs.
The Africa-focused firm also reported that good evidence of communication with the Owo-1 discovery wells and the Enyenra appraisal wells confirms the significant extent of the Enyenra light oil field.
Located just under 4.5 miles (7 kilometers) south west of Enyenra-2A and almost 13 miles (21 kilometers) south of the Enyenra-3A well which defined the northern end of the Enyenra oil field, the Enyenra-4A well was drilled to define the southern extent of the field.
Results of drilling, wireline logs, samples of reservoir fluids and pressure data show that Enyenra-4A has intersected 105 feet (32 meters) of net oil pay. Pressure data from the oil leg has demonstrated that the oil is in static communication with the oil seen in the other wells in the field and indicates a continuous oil column of approximately 1,970 feet (600 meters).
The Ocean Olympia drillship drilled Enyenra-4A to a total depth of 13,695 feet (4,174 meters) in water depths of 6,160 feet (1,878 meters). Wireline logging has been completed and injectivity tests are under way to provide important data for the design of the water injection system.
On completion of operations, the well will be suspended for later use. The drillship will return at a later date to the Deepwater Tano block to perform a drill stem test on the oil zone in the Ntomme-2A well.
Tullow (49.95 percent) operates the Deepwater Tano license and is partnered by Kosmos Energy (18.00 percent), Anadarko Petroleum (18.00 percent), Sabre (4.05 percent) and the Ghana National Petroleum Corporation (10 percent carried interest).
“This bold step out is an excellent result which is further enhanced by the quality and thickness of the reservoirs found at this downdip location,” said Tullow Exploration Director Angus McCoss.
“Proving a 600-meter oil column over a distance of 21 kilometers with three appraisal wells is a significant achievement which was only possible through the use of highly refined geophysical techniques. The appraisal of the Enyenra field will now continue with the monitoring of the pressure gauges deployed in several wells to determine the level of dynamic connectivity within the system and to further refine the estimates of oil in place.”
