By OGJ editors
HOUSTON, Jan. 21 -- Harvest Natural Resources Inc., Houston, is evaluating Cretaceous gas and Eocene oil potential on 60,000 gross (36,000 net) acres in the central Uinta basin between giant Altamont-Bluebell and Monument Butte oil and gas fields.
Harvest plans to commingle and test eight tight Mesaverde intervals at its Bar F 1-20-3-2 well in Duchesne County, Utah. Total depth is 17,566 ft. The company ran hydraulic fracs on the eight intervals and tested selected intervals at rates of 1.5 to 2 MMcfd of gas.
Results so far haven’t determined the commerciality of standalone Mesaverde development but have established the presence of producible gas from a large part of a gross sand interval more than 3,000 ft thick, the presence of overpressure, and evidence of natural fracturing in some intervals.
Harvest said the main technical concern is whether the Mesaverde will have adequate porosity and permeability to produce commercial quantities over a large area.
The company hopes to cut development costs to less than $2.50/Mcf, verify long-term stable production rates and associated reserve potential for a single vertical well, and confirm the areal extent of producible Mesaverde reservoir via appraisal drilling and-or 3D seismic.
When it completes the Mesaverde tests, Harvest plans to test multiple oil-bearing intervals logged in Eocene Lower Green River and Upper Wasatch at 6,000-9,500 ft. Those tests are to involve multiple frac stages and associated flow tests in the first quarter of 2010.
Goal there is to learn whether the oil-bearing zones are capable of commercial production in a stand-alone vertical or horizontal well that would be drilled solely to develop them.
If commercial at Bar F, the formations may be producible over much of the northern part of Harvest’s land position, with development likely on a location by location basis. The Bar F well is 6-8 miles south of Altamont-Bluebell field, where the two formations are main pay zones.
Harvest also participates in an eight-well appraisal-development program, operated by Newfield Exploration Co., Houston, to produce oil and gas from the Green River formation on the southern part of Harvest’s acreage in a northern extension of Monument Butte field. Harvest has 43% working interest.
The companies formed a 320-acre area of mutual interest containing the eight drilling locations. Three wells on production averaged a combined 1,600 b/d of oil and 1.8 MMcfd of gas the last 7 days. Two other wells are drilled, and the other three are to be drilled in January and February 2010.
Results to date exceed predrill expectations for production rates and at $800,000/well are in line with predrill cost estimates, Harvest said. Five to 10 more viable 2010 drilling locations are possible, and Harvest has more acreage to the west and on strike.