Talos Energy Inc. said it completed the Zama-3 appraisal well, the final appraisal well to define the Zama discovery on Block 7 offshore Mexico’s Sureste basin. Talos operates Block 7 in a consortium with Sierra Oil & Gas, a Wintershall DEA company, and Premier Oil.
The Zama-2 and Zama-2 ST1 appraisal penetrations, both drilled during this year’s first half, met or exceeded the consortium's expectations (OGJ Online, Apr. 16, 2019). The Zama-3 well was drilled 1½ miles south of the Zama-1 to test the southern extent of the reservoir, Talos said.
The Zama-3 well was drilled downdip of the Zama-1 well and penetrated the oil-water contact in the southern portion of the field, consistent with the geophysical flat spot seen throughout the downdip edge of the reservoir.
The well logged 1,000 ft of gross TVD sand and 748 ft of gross TVD pay-bearing section, consistent with expectations. Zone 3 exceeded expectations with a net-to-gross ratio of 85-90%. Zones 3 and 4 comprise most of the Zama resource potential.
Talos and partners are evaluating data and samples collected from four penetrations of the Zama reservoir, including 1,450 ft of whole core, fluid samples from 30 separate reservoir points, 180 pressure points, 25 logging runs, and two extended flow tests.
Based on the preliminary information, Talos expects an updated evaluation will fall in the upper half of the previously provided pre-appraisal guidance of 400-800 million boe.
Talos and partners are advancing front-end engineering and design work streams as well as unitization discussions with Petroleos Mexicanos with the goal of making a final investment decision on the project in 2020, pending required government approvals.