History of the oil shale industry in the United States Act of 1985 which among other things abolished the United States' Synthetic Liquid Fuels Program. Union finally bowed to continued low oil prices and closed the project in 1991, rather than complete the US$2 billion project. Over several decades, some of the world's largest oil companies (Amoco, Arco, Chevron, Exxon, Gulf, Phillips, Shell, Sohio, Sunoco, Texaco, Union Oil) had spent billions of dollars to start an oil shale industry in the Green River Formation, the world's largest oil shale resource. But in the end, cheap petroleum prices drove oil shale out of business. Even after the oil shale bust, some
S/2004 S 6 dissipate on a timescale of years or months. Notably, an imaging sequence covering an entire orbital period at 4 km resolution taken on November 15, 2004 (soon after 's discovery) failed to recover the object, while it has been seen again later. The lighting conditions in 's part of the orbit were different during these two observations, however, with the discovery being made when the region was strongly backlit by the sun. A suggested resolution of the absence in November is that 's visibility is primarily due to a diffuse cloud of fine dust that is much brighter in forward