Offshore staff
HOUSTON – Talos Energy says the Zama-2 appraisal well in block 7 offshore Mexico has achieved most of the partnership’s objectives.
This is the first of three appraisal wells designed to improve definition of the resource potential in the shallow-water Zama oil discovery.
Zama-2 was drilled in a down-dip location, 1.3 mi (2.1 km) north of theZama-1 discovery well with the primary goals of confirming the geological model and determining the oil-water contact.
The initial phase was completed successfully on Jan. 20, 28 days ahead of schedule and 25% below initially projected costs. The well reached the top of the Zama reservoir at a TVD of around 10,759 ft (3,279 m), with the following highlights:
- A contiguous Zama sandstone interval of 1,676 ft (511 m) of gross TVD sand, materially thicker than the Zama-1 sand slightly thicker than the pre-drill estimates. In addition, the well intersected various other thick, wet sands of a similar age directly beneath the main Zama horizon within the Upper Miocene, with rock properties similar to analogous Upper Miocene sands in the US Gulf of Mexico.
- The well logged roughly 581 ft (177 m) of gross TVD oil pay before reaching the oil-water contact, which is estimated to be at 11,254 ft (3,430 m) TVD, 100 ft (30 m) deeper than anticipated. Talos currently estimates the net-to-gross factor within this pay interval at 68-73%, with rock properties in line with those at the Zama-1 location.
- Pressure data helped confirm the oil-water contact depth, also suggesting that this northern leg of the reservoir is connected to the Zama-1 discovery well. The Zama-2 vertical side track and the Zama-3 well should improve understanding of reservoir connectivity and consistency.
The final aim of this well was to test a deeper exploration prospect in a stratigraphic trap, named Marte. However, the sands encountered were not hydrocarbon bearing, although the information gathered should assist evaluation of the aquifer support of the main Zama reservoir and other possible prospects on the block.
Testing of Marte came in well under budget at around $2.5 million, and Talos added that the full cost of the Zama-2 well will be recoverable once commercial production begins from Zama.
President and CEO Timothy S. Duncan said: “We are staying focused on working with urgency to meet the project timeline to achieve first oil by the second half of 2022.”
Next up will be an up-dip vertical penetration in the Zama reservoir from the main borehole of the Zama-2 well, which will be cored with a drillstem test to follow.
The second appraisal well, Zama-3, will be drilled south of Zama-1 and should help delineate the reservoir continuity and quality in the southern part of the field.
01/24/2019
