Stratigraphic sections of the Phosphoria Formation in Montana, 1947-48 Phosphoria Formation Swanson, Roger Warren 1914- creator author. Geological Survey (U.S.) issuing body. United States Bureau of Reclamation, sponsoring body. U.S. Atomic Energy Commission sponsoring body. text bibliography dcu 1953 monographic eng remote 1 online resource (31 pages) : illustrations, map. by R.W. Swanson [and three others]. "This report concerns work done partly OB behalf of the U. 8. Bureau of Reclamation and partly on behalf of the and partly on behalf of the U.S. Atomic Energy Commission and is published with the permission of the Commission." Includes bibliographical references (page 3). n-us-mt Phosphoria Formation Geology, Stratigraphic Permian Phosphate rock Montana Geology, Stratigraphic Permian Geologic Period Phosphate rock Montana From 230 to 280 million years ago fast I 19.4/2:209 I 19.4/2:209 Stratigraphic sections of the Phosphoria Formation in Montana, 1947-48 (OCoLC)5143272 Geological Survey circular ; 209 https://purl.fdlp.gov/GPO/gpo108916 OCLCE 160311 20190122121019.0 in00004011149 eng