Apr 145 min
Grand Gulf Energy (GGE) identified three new deeper stacked potential helium reservoir targets within the Red Helium Project, supplementing the previously established Mississippian Leadville dolomite and Devonian McCracken sandstone targets. These targets were pinpointed after comprehensive seismic, petrophysical, completion, and production reviews of analogue fields, promising additional resource and gas flow rate potential.
The new targets, which include the Devonian Ouray/Elbert Dolomite, Cambrian Lynch Dolomite, and Cambrian Ignacio Sandstone, offer distinct geological characteristics that enhance the play's prospective value. The Devonian Ouray/Elbert Dolomite, found beneath the McCracken, features good porosity and is historically productive when co-mingled in nearby wells. The Cambrian formations, positioned closer to the granitic basement, are underexplored but show high porosity levels in limited test wells, suggesting substantial untapped potential. The updated well design plans to thoroughly case and perforate the entire basin's stratigraphic section, aiming to maximise extraction from these deeper reservoirs for only a modest additional cost. This strategic approach positions the Red Helium Project to potentially expand its helium resources well beyond the initial estimates of 13.6bcf, derived from the primary Leadville and McCracken formations.
Press Release:
Grand Gulf Energy Ltd is pleased to announce that, following a seismic, petrophysical, completion and production review of analogue helium fields in the region, the Company has identified three highly prospective deeper stacked potential helium reservoir targets that will be tested in future well operations.
The updated well design and engineering (casing and perforating the entire basinal stratigraphic section), will add significant helium upside to the already identified Mississippian Leadville dolomite (10.9 bcf) and Devonian McCracken sandstone (2.7 bcf) targets. In a success case, deeper helium reservoirs will be perforated and tested for modest additional cost.
Managing Director Dane Lance commented:
“We’re thrilled to announce the addition of three under-explored, highly prospective additional deeper targets on top of the primary Leadville and McCracken targets. These targets provide the potential for both extra resource build and gas flowrate upside.
The improved case and perforate well design provides zonal isolation, with the identified zones to be logged as a part of the original well plan, and potentially tested for a modest additional cost.
The addition of the three independent deeper targets, takes the total zones to be tested in future Red Helium project well operations to five, providing exciting upside to the already geologically de risked primary Leadville and McCracken targets which alone target a 12.7 bcf1 helium resource.”
Red Helium Project Area Deeper Proven Pay (sub-Leadville)
Four historic wells (Texas Coal-1, Gulf Unit-2, Redd-1, Crittenden Phillips-1) in the Red Helium project have drilled below the Leadville. All are interpreted as gas filled to base below the Leadville, including the additional deeper helium targets.
The horst region of the Red Helium project has proven gas in the Leadville and McCracken, with the maximum intersection interpreted as gas bearing over a 900 foot gross zone, incorporating all deeper targets. Earp-1 (permitted) is planned as an up-dip twin of Gulf Unit-2 which identified a proven gas reservoir.
Figure 1: Red Helium project area showing structural closure, six historic wells, Jesse-1A and Jesse-2 locations, and the proposed Jesse-3 (up-dip twin to Redd-1) and Earp-1 (up-dip twin to Gulf Unit-2) locations.
The Jesse structure (Redd-1) has proven gas in the Leadville, with gas on logs to the base of the McCracken. The well is interpreted as gas bearing over a 700 foot gross zone, with potential for a deeper gas column up to 1,100 feet to the granitic basement. Jesse-3 (subject to permitting) is planned as an up-dip twin to Redd-1.
Figure 2: Stylised cross-section showing the Jesse-1A discovery well, and the proposed Jesse-3 (up-dip twin to Redd-1) and Earp-1 (up-dip twin to Gulf Unit-2) locations, and the Jesse-1A discovery well and proposed sidetrack.
Proximal Analogue Seismic, Petrophysical Analysis and Production Performance Review
The Company has reviewed the Red Helium area project wells in conjunction with detailed field studies on the Lisbon oil, gas, and helium field (25 miles to the north) and the Doe Canyon helium field (15 miles east).
Furthermore, the Company is in the process of reviewing seismic, petrophysical, completion and production information on several proximal analogues, both producing and under development, including the Tocito Dome helium field (90 miles south), and three proximal helium discoveries currently under development: Three Mile Unit (25 miles north-west), Hatch point (30 miles north west) and Tricentrol (25 miles south-west).
Figure 3: Four Corners new helium production and recent helium discoveries under development
Lisbon helium field is a mature field, having produced from both the Leadville and McCracken, with the identified deeper targets often completed and co-mingled with McCracken production. Tocito Dome helium field (90 miles south) originally targeted the Leadville, however initial exploration indicated a relatively tighter reservoir as a function of limited dolomitization/and resulting secondary porosity.
Tocito Dome now primarily targets sub-Leadville geology, with an average porosity of 7%, routinely completing zones below 5% porosity. Red helium project deeper intersections show porosities exceeding 10% in all deeper reservoir targets. Based on analogue field data, the deeper targets can present both as a continuous gas column and separate gas accumulations with inter-formation seals.
Proximity of the deeper formations to the helium source, inter-formation seal/baffle potential, and the helium trapping potential of lower porosity reservoirs, relative to the prolific Leadville, all provide helium concentration upside for the Red Helium deeper formations.
Figure 3: Log section of selected deeper well penetrations in the proximal Red Helium project area, showing exceptional porosity development in the Redd-1 and Gulf Unit-2 McCracken and deeper targets with proven gas.
The average produced helium concentration at Tocito Dome is 7%. The high helium concentrations observed are interpreted to be due to a combination of the above factors, the local helium (pre Cambrian granitic basement) source, and other geologic gas sources and migration pathways.
Three Mile Unit, Hatch Point and Tricentrol all had exceptional helium-charged Leadville reservoirs with commercial gas flow rates and are currently under development. Three Mile Unit and Tricentrol have proven deeper pay below the Leadville. These fields will be the subject of a future update once field studies are finalised.
Red Helium Deeper Target Geology
Figure 4: Paradox Basin stratigraphic column showing helium source rock with primary Leadville/McCracken and deeper targets.
Devonian McCracken Sandstone (Secondary Target) ~380 Ma
Regional proven helium producing fluvio-deltaic sandstone formation. Routinely completed in Lisbon and Tocito Dome and co-mingled, with initial production rates in excess of 1 million cubic feet per day (mmcfd) and several examples exceeding 5 mmcfd. Both Redd-1 and Gulf Unit-2 demonstrate excellent net pay exceeding 30 feet, with porosities exceeding 10%. The Company has a 2.7bcf gross P50 prospective resource in the McCracken.
Devonian Ouray/Elbert Dolomite (Deeper Target) ~360 Ma
Carbonate (dolomite) formation, including breccia and limey shales across a 100 foot gross zone. Productive in a several wells in Lisbon, with porosity on logs in most wells, productivity is unknown as zone is produced co-mingled. Routinely completed in Tocito Dome and co-mingled. Redd-1 and Gulf Unit-2 shows porosity development exceeding 10%.
Cambrian Lynch Dolomite and Cambrian Ignacio Sandstone (Two Deeper Targets) ~520 Ma
Carbonate (dolomite) across a 100 foot gross zone separated by a widespread marine shale to the variable clastics (sandstone), potentially a granite wash, across a 150 foot gross zone which sit directly on the pre-Cambrian weathered/igneous basement helium source. Gas test in Lisbon of 0.5mmcfd pre-stimulation techniques, and likely to be greatly improved with modern stimulation. Produced in the Lisbon field co-mingled with limited isolated production history. Highly under explored in the region with limited penetrations. Gulf Unit-2 has exceptional porosity development exceeding 15%, whilst Redd-1 did not penetrate below the McCracken.