"U.S. Atomic Energy Commission," . . "Geology, Stratigraphic." . . . . . . . . . . . . . . . . . . . . . . . . . "Uranium and other trace elements in petroleums and rock asphalts" . "Uranium and other trace elements in petroleums and rock asphalts"@en . . . . "Uran." . . "From 345 to 405 million years ago" . . "Geology, Stratigraphic Devonian." . . "Bitumen." . . "Erdöl." . . "Devonian Geologic Period." . . "Geological Survey (U.S.)," . . . . "Uranium ores." . .