Painter Reservoir Field--Giant in Wyoming Thrust Belt

Abstract

Painter Reservoir field is the largest of several recent Nugget Sandstone hydrocarbon discoveries in the Wyoming Thrust Belt province. The field is located in Uinta County, Wyoming, 5 mi (8 km) northeast of the town of Evanston and on trend with the Clear Creek and Ryckman Creek accumulations, 5 and 10 mi (8 and 16 km), respectively, northeast, which are also productive from the Nugget. The field discovery, Chevron-Federal 22-6A, was drilled in mid-1977 on a seismic anticlinal structure. The Nugget Sandstone was entered at 9,728 ft (2,918 m), and 1,355 ft (407 m) was penetrated to the total depth of 11,083 ft (3,325 m). After extensive testing, potential of the well on October 22, 1977, was 410 bbl of oil per day and 859 Mcf of gas per day on 15/64-in. choke, flowing tubing pressure 1,275 psi (8,791 kPa). Flow rates as high as 1,500 bbl of oil per day were recorded on larger chokes. Gravity of the oil is 48.4° API. Active development began immediately and is still in progress. Field limits and structural configuration are not yet fully decided, but seismic and drilling data indicate an overturned fold associated with the hanging wall of the Absaroka thrust. Present drilling has established an oil and gas column of over 1,000 ft (300 m). The producing Nugget is a cross-bedded, quartz sandstone over 850 ft (255 m) thick with an average porosity of 14.1% and permeability ranging from 0 to 1,000 md. Analysis of the oil suggests a Cretaceous source.