US-focused oil and gas junior Winchester Energy (ASX: WEL) has announced the prospective oil resources of three recently identified prospects at its White Hat Ranch project in the prolific Permian Basin of Texas.
The company first unveiled the prospects to investors at a conference in Western Australia last month. Named El Dorado, Mustang and Spitfire (originally referred to as the Strawn Channel), they were identified through 3D seismic and well control as “compelling drill targets”.
Today, Winchester has declared a cumulative gross prospective resource for the prospects of 7.796 million barrels of oil.
The figure was estimated probabilistically on an unrisked best estimate basis by independent US-based petroleum consultants Mire & Associates, subject to oil and productive reservoir targets being present in the prospects.
Breaking it down, the estimate is comprised of a best estimate oil resource of 1.269 million barrels at El Dorado, 2.037 million barrels at Mustang and 4.49 million barrels at Spitfire.
Winchester has a 100% working interest in El Dorado and a 75% stake in the other two prospects, giving the company a total net prospective resource of 4.87 million barrels of oil.
Winchester based the recoverable barrels per acre-feet for the prospects on the adjacent Sugg oilfield and its White Hat Ranch field’s producing well data.
It also used 3D seismic mapping to calculate the trapping area and well logs to determine the prospective reservoir thickness.
The El Dorado prospect, located in the west of the White Hat Ranch lease, is a large four-way closed structure that has been mapped at multiple levels.
Only the Ellenburger carbonates and the Strawn formation were considered in the determination of prospective resources, with an estimated probability of success for both targets in this prospect being 48%.
Spitfire, further east of El Dorado, is interpreted to be an incised valley fill of Strawn formation sediments composed of sands and carbonates and has an estimated probability of success of 28%.
The Mustang prospect lies further north-east of the other two prospects and is closest to the existing White Hat Ranch wells.
About half a mile from Mustang’s proposed well location lies the White Hat 20#2 well, which has produced more than 30,000 barrels of oil from the Strawn sand in its 17 months of production.
According to Winchester, the results from White Hat 20#2 provide confidence that a stratigraphic trap is present at Mustang.
Vertical drilling of these three prospects is planned in the next six months.
Meanwhile, the company is focused on developing the Strawn formation in its White Hat 39#1L well, which recently produced 1000 barrels of oil over 10 producing days of swabbing and pumping.
Winchester’s stock rose 6.25% to $0.034 on today’s news by afternoon trade.