Ultra Petroleum Corp. Announces Field Update.

VANCOUVER, B.C.--(BUSINESS WIRE)--July 9,1998--Production casing has been run to a depth of 12,085 ft. at the Stud Horse Butte 3-23 well in Jonah Field. Top of the overpressure was encountered at 9,310 ft. and logs indicate an above average Jonah Field well. Halliburton (NYSE:HAL) and Ultra Petroleum Corp. (VSE:UP) are designing a completion program for this well to be initiated by month end.

Halliburton, as operator for Ultra, will move the rig next to the SHB 9-24 location, which will be the second of seven wells planned for the current Halliburton/Ultra Stud Horse Butte project.

In the Mesa project, Halliburton and Ultra are drilling below 6,500 ft. at the Stewart Point 3-28 well in partnership with Western Gas Resources (NYSE:WGR). This is the second of six earning wells in the Mesa Project, located on the northern plunge of the Pinedale anticline approximately 24 miles NNW of Jonah Field.

During the next two weeks, the following completions are planned:

-- A stage one frac at the Lovatt Draw well in partnership with Green

River Petroleum (ASE:GRP) and Western.

-- A stage two Overbalanced Perf at the War Bonnet 9-23 in partnership

with Arrowhead (VSE:AOW) and Western.

-- A stage four frac at the Lizard Head 11-28 in partnership with Colt

Energy (ASE:COE) and Western.

-- Two fracs (stages 8 and 9) at the Mesa 15-8, in partnership with

Western.

All of these wells are located north of Jonah Field and were drilled through overpressured sandstones that exhibit similar characteristics to the multiple reservoir sands in the Jonah Field.

The Vancouver Stock Exchange has not reviewed and is not responsible for the contents of this news release.

Contact: Mark Jarvis 609 West Hastings Street, Suite 1100, Vancouver, B.C., Canada V6B 4W4 Tel: [phone]. Toll Free: 800/688-5651. Facsimile: 604/688-4712. http://www.ultrapetroleum.com. e-mail: [e-mail].

    CONTACT: Ultra Petroleum Corp.
              Mark Jarvis, 604/669-0964
              www.ultrapetroleum.com