Abstract

Over 160 horizontal wells with highly variable results have been drilled in the Uteland Butte play of the Uinta Basin. The best wells have produced more than 300K barrels in the first 12 months of production, with conservative EUR’s above a million barrels per well. Conversely, the poorest Uteland Butte wells have initial production rates of less than 10K barrels in the first year and will never recoup their drilling costs. Pore pressure, oil viscosity, well length and well completion are recognized as important controls on well productivity. Less understood but of equal importance is the variability in reservoir types across the Uteland Butte play. The Uteland Butte can be divided into sub-plays by district using the dominant pore systems in each area. In this presentation I show how the Uteland Butte play can be defined four distinct sub-plays within the Uinta Basin; 1) Intergranular dominated porosity, 2) Intercrystalline-pore dominated dolomite, 3) Mixed intercrystalline-organic porosity, and 4) Organic porosity. By recognizing the important differences these pore systems exert on best development practices and then accurately mapping them across the basin, operators, interest owners and regulatory agencies can more efficiently plan operations and fully exploit what is likely Utah’s largest oil reservoir.

BIO

I was born and raised in the geologic center of the universe, the Uinta Basin.  Choosing a college was difficult and I tried out USU, BYU and the U of U, eventually earning a BS and MS in geology from BYU and an MBA from the U.  Since graduating, I have worked for BP America (Houston), Questar (Salt Lake), SM Energy (Billings), Newfield (Houston), and am now at Wasatch Energy in Provo, mostly working the Uinta Basin plays where we are currently drilling 20,000 ft deep wells.  It’s fun.  I am at present the AAPG Visiting Geoscientist coordinator for the Rockies, the UGA president, on the boards of the UGS and AAPG RMS and served on the board for the Montana Geological Society for four years, including as president.  I married a girl from the Klamath ophiolite, and together we have five children, none of whom like rocks but will go down the occasional slot canyon with me.