The company’s entry into the North Dakota portion of the Williston Basin has had a promising start with oil and gas shows at the Harstad 1-15H well.
Samson said yesterday that top of the target zone, the Bluell Formation, was intersected at 10,126ft and both oil and gas shows were recorded.
A 5½-inch casing string has been run to 10,102ft and has been cemented. Harstad 1-15H is currently drilling ahead at 10,322ft.
Samson, which is not the operator, said the oil show was described as a visible oil stain, exhibiting a fast-blooming cut and a bright yellow residual ring, while the gas show peaked at 194 units over a background of five units.
“Both shows are indicating that the Bluell, is as expected, oil saturated,” said managing director Terry Barr.
Samson’s working interest in the well is 34.5%. Due to ownership differences across the leased area, the company said its total working interest in the prospect is 41%.
Forward operations from this point would be to continue to drill the horizontal section, which is planned for 5000ft, according to Samson.
Harstad 1-15H is targeting the oil-productive Bluell Formation, which is developed in the oil field using horizontal completions.
In the Williston Basin, wells are often drilled vertically to target zones, then extended horizontally for more than 1000m through the formations. Horizontal wells are now very common in the Williston Basin and have a track record of significantly boosting oil production in this province.
The Williston stretches across parts of the US states of North Dakota, South Dakota and Montana, and across the Canadian border into Saskatchewan and Manitoba.
Annual oil production from the US portion of the basin alone is currently about 68MMbbl.
It has risen significantly in recent years, almost entirely because of field extensions and new reservoir discoveries in old fields.
This has been driven largely by improved drilling and fracture stimulation technologies and use of 3D seismic data.
At the end of 2005, the US Department of Energy estimated North Dakota’s proved reserves at 418MMbbl and Montana’s at 427MMbbl.
In Montana, the Williston landscape is mostly rolling prairies, in North Dakota it is mainly very flat farmland. The basin offers relatively easy access to drilling locations and an oil-friendly local culture, according to the three Australian companies operating in the region – Samson, Emerald Oil & Gas and Sundance Energy.
How Green was my canyon
Meanwhile in Wyoming, successful test results and gas flows from the Baxter Shale have been recorded at the Samson-operated Green Canyon 29-2 well in the Green River Basin.
Green Canyon farm-in partner Fall River yesterday said the program involved the re-entry of an existing well, which was cased through the Baxter Shale, perforating selected intervals and subjecting them to fracture stimulation.
It said the Green Canyon 29-2 well tested a gross interval of 305 feet (92.9m) out of a total 3400ft Baxter shale interval.
Samson said initial flow rates through the casing are estimated at 100,000 cubic feet of gas per day plus 48 barrels of load water per day through a one-inch choke.
The company described the results as “encouraging” and said it expected flow rates would increase on the well as the load water is recovered, although “it was too early to estimate flow rates”.
Samson is wholly funding the cost of the test well, which is a re-entry of an existing well and designed to demonstrate the commercial potential.
Fall River is earning a 15% working interest in the Green Canyon leases, which will be completed following its contribution of 25% of the cost of the next Baxter well in the area.
