1910–1912 Colorado residents stake first oil shale claims.

1912–1916 U.S. Geological Survey reconnaissance team estimates 40 billion barrels of oil recoverable from Green River shale formation.

1917 First oil shale retort (kiln) in Colorado.

1924–1929 U.S. Bureau of Mines produces 3,600 bbl of oil from an experimental retort

1944-1956 Experimental extraction technologies funded by U.S. Synthetic Liquid Fuels Act at Anvil Points; some production

1955–1961 Union Oil of California (Unocal) builds oil shale plant north of Parachute, Colorado. Plant operates for 18 months and produces as much as 800 bpd. Operation is shut down due to operational problems and price uncertainties.

1964–1972 The Oil Shale Company (Tosco), along with partners Sohio and Cleveland-Cliffs, builds and operates the Colony oil shale plant 17 miles north of Parachute, and produce 270,000 bbl by 1972.

Early 1970s Shell conducts in situ steam injection research in oil shale and nacholite located along Piceance Creek, Colorado.

1966–1982 PARAHO Company, in partnership with 17 other companies and the U.S. federal government, operates new Anvil Points facility. Retort problems and high costs force the program
to close.

1974 Federal government agrees to lease two tracts of oil shale lands in Piceance Creek Basin, Colorado. Shell and Ashland Oil join Colony project.

Late 1970s Shell, Ashland Oil, Cleveland-Cliffs and Sohio sell out of Colony Project, leaving Arco and Tosco each with 50 per cent interest.

1980 Congress approves $14 billion for synthetic fuels development. Exxon buys Arco’s interest in Colony project. Exxon and Tosco begin construction of Colony II, which produces 47,000 bpd by 1987. Amoco produces about 1,900 bbl of in situ shale oil.

1982 World oil demand drops dramatically.

1982 On “Black Sunday” (May 2nd), Exxon announces closure of Colony II project, citing higher than expected construction costs and lower demand for oil.

1985 Congress ends funding under Synthetic Liquid Fuels program.

1991 Occidental Petroleum announces closure of project near Rio Blanco. California’s Lawrence Livermore National Laboratory plans to build $20 million experimental oil shale plant at Parachute.

1993 U.S. House of Representatives ends funding of additional oil shale tests to Lawrence Livermore Laboratory.

2000–present Shell conducts in situ heating technology research program at its Mahogany oil shale property.

(adapted from Western Colorado Oil Shale: A Chronology, Shell Oil Company)