Partners in the Duyung Production Sharing Contract (PSC) in the West Natuna basin offshore Indonesia, which contains the Mako gas field, have agreed the upcoming drilling program.
Partners in the Duyung PSC are Empyrean Energy, Conrad Petroleum, and Coro Energy.
According to the partners’ statement on Monday, the campaign will comprise two wells, one exploration well designed to test the Tambak prospect beneath the central area of the Mako gas field, and one appraisal well designed to appraise the intra-Muda sandstone reservoir in the southern area of the Mako field.
The drilling campaign is anticipated to start in September 2019, with each well taking approximately 33 days to drill and test. The gross cost of the program is expected to be approximately $17 million to the partners on a fully tested basis, including rig mobilization and de-mobilization.
As part of the deal to acquire its 15% interest in the PSC, Coro Energy will be contributing $10.5 million to the total cost of the drilling campaign with the balance to be covered by the partners pro rata to their respective interests. Empyrean has an 8.5% interest in the PSC.
Two-well campaign
The Tambak prospect is an inverted anticlinal structure located beneath the main Mako gas field in the central area of the field. The prospect contains approximately 250 Bcf of prospective resources in the mid-case and is risked at a 45% chance of success. The well will be drilled to a total depth of approximately 1,370 meters true vertical depth sub-sea (TVDSS), with a testing suite planned for both the intra-Muda Mako reservoir level as well as the Lower Gabus prospective target horizons.
The second well in the program is an appraisal well which is designed to intersect the intra-Muda reservoir at approximately 380 meters TVDSS. A full evaluation suite including coring, wireline logging and open hole testing of the reservoir section is planned. The well will provide an important calibration point for the southern area of the field and is planned to demonstrate further contingent resource, which in turn will support the gas marketing efforts. An independent review by Gaffney Cline & Associates ascribed gross 2C resources of 276 Bcf (48.78 MMboe) of recoverable dry gas in the Mako field with gross 3C resources of 392 Bcf (69.3 MMboe) representing additional field upside.
Empyrean CEO, Tom Kelly , commented “Empyrean looks forward to this exciting drilling program that is designed to both appraise the existing Mako Gas Discovery as well as testing the deeper Tambak exploration prospect. This program is a crucial step in the Plan of Development for Mako and paves the way for completion of gas sales negotiations as well as potentially increasing resources at Mako and possibly below the Mako discovery.”