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Sublette County, Wyoming; 1947


This is really cool stuff.


In 1947 Superior Oil Company of California (founded in 1921, later Mobil Oil) undertook a rank wildcat in Sublette County, Wyoming, near Pinedale and in the Green River Basin along Pacific Creek; the well took two years to TD.

The wildcat was based on new, two dimensional seismic technology showing a very large, deep seated anticline.


The Pacific Creek Deep Unit Test No 1. was drilled to a vertical depth of 20,251 feet (Rocky Mountain record) after setting 7 inch casing, its fourth string of protective casing, to 19,267 feet. That string weighed 297 tons and set a record never before achieved for hook load capacity in North America.

The well was logged by Schlumberger 10 different times. A total of 19 different drill stem tests were run and the well was perforated 10 times and swab tested before being plugged and abandoned on August 18, 1949. The last DST run below the 7 inch shoe to total depth in the Frontier Formation showed BHP to be 13,350 PSI and had bottom hole temperatures of 325 degrees F.

The well was drilled in two stages; the first rig, owned and operated by Dyer and Rice Drilling Co. drilled to 9,881 feet vertical depth to test the Mesaverde Formation sequence and the well was then temporary abandoned.

Stage 2 of the well was drilled by a Superior owned rig with Ideal components and, at the time, was the biggest land rig in North America.

This Superior rig had, at the time, the biggest mud circulating system in the world with 3 power plants generating almost 2000 HP. 150 foot high, standard derrick, below, that supposedly had hook load capacity of nearly 800,000 pounds.

Superior Oil, Pacific Creek Deep Unit No. 1; 1947. All black and white photos by John Collier (1913-1992) and part of the Standard Oil of New Jersey Collection

In 1978 Rainbow Resources drilled a 23,081 foot dry hole on the same Pacific Creek anticline, in the same Superior Pacific Creek Deep Unit, to test the Madison Formation and it too was a dry hole.

The Green River Basin contains the great Jonah Field on the Pinedale Anticline that is the largest gas field in all of Wyoming and at one time was the sixth largest in the United States. There are, or were, before the shale oil and gas industries ruined gas prices, a number of horizontal wells being drilled in the Pinedale area just a few years ago.


I did a 3 month stint in Wyoming as a kid, in the Green River Basin. That rock was so hard that sometimes in an 8 hour tower we'd never even made a connection. You could eat scrambled eggs off any part of that drilling rig, even the floors, because we had it hospital like clean. To keep us hands busy the tool pusher made us take care of his stinking garden behind his trailer, and prune flowers around his front porch. He was a tough sumbitch and plum anal about his rig; it must have been repainted 30 times. If you looked sideways at that dude he'd throw a wire brush and a scraper at you and tell you he did not want to see you for the next 3 days. "If it ain't moving, clean it," he'd holler.

Big brown trout live in Pacific Creek and in the Green River around Superiors old exploration efforts; they rise for summer bugs and can be pretty accommodating about it all. If you can avoid dumb Californians visiting Jackson Hole it's possible to find quiet water with spectacular views of the Tetons.


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