The Potomac formation in Virginia Fontaine, William Morris 1835-1913 creator author. Geological Survey (U.S.) issuing body. text bibliography dcu 1896 monographic eng remote 1 online resource (149 pages, II pages of plates) : illustrations, color map. by William Morris Fontaine. Title from title screen (viewed June 23, 2015). Includes bibliographical references and index. n-us-va Geology Virginia Geology, Stratigraphic Cretaceous Cretaceous Geologic Period Geology Geology, Stratigraphic Virginia From 65 to 140 million years ago fast I 19.3:145 I 19.3:145 Potomac formation in Virginia Fontaine, William Morris, 1835-1913. (DLC)gs 05000709 (OCoLC)271926 Bulletin of the United States Geological Survey ; no. 145 https://purl.fdlp.gov/GPO/gpo58574 OCLCE 111115 20211120173126.0 in00003597422 eng