What are the most active crude oil-producing regions in the United States? The Permian Basin and Eagle Ford Shale, according to the U.S. Energy Information Administration's rig counts. Among more than 1,500 oil rigs in operation around the nation as of early November, more than 560 were in the Permian Basin and more than 200 were in the Eagle Ford Shale. By comparison, about 190 rigs were operating in the Bakken Shale. And at third quarter's end, the Permian Basin and Eagle Ford Shale housed 7,787 and 3,541 wells, respectively, while 2,062 wells were located in the Williston Basin, which...