Only recently has the Williston Basin, which gets its name from the City of Williston located on the Missouri River 20 miles east of the Montana-North Dakota border, become of great interest to the exploration departments of the oil industry. This interest in one of the largest and oldest geological basins in North-America was created by discoveries of oil in commercial quantities. A minor discovery was made in February', 1951 near Virden, Manitoba, followed by the discovery' of the Clarence Iverson Well in the vicinity of the Nesson Anticline on the 4th of April, 1951, followed by the discoveries of September, 1951 in the H. O. Bakken Well in the Tioga pool and in December of the same year the Shell Oil Company's discovery at Richey, Montana. The Virden Well is located near the northeastern border of the Williston Basin and Madison production was developed there by the California Standard Company. The Clarence Iverson Well was developed by the Amerada Petroleum Corporation and it produced from the Devonian and Madison.