Sequences in the Cratonic Interior of North America

Research Article| February 01, 1963 Sequences in the Cratonic Interior of North America L. L SLOSS L. L SLOSS Dept. Geology, Northwestern University, Evanston, Ill Search for other works by this author on: GSW Google Scholar Author and Article Information L. L SLOSS Dept. Geology, Northwestern University, Evanston, Ill Publisher: Geological Society of America Received: 13 Nov 1961 First Online: 02 Mar 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 Copyright © 1963, The Geological Society of America, Inc. Copyright is not claimed on any material prepared by U.S. government employees within the scope of their employment. GSA Bulletin (1963) 74 (2): 93–114. https://doi.org/10.1130/0016-7606(1963)7493:SITCIO2.0.CO;2 Article history Received: 13 Nov 1961 First Online: 02 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation L. L SLOSS; Sequences in the Cratonic Interior of North America. GSA Bulletin 1963;; 74 (2): 93–114. doi: https://doi.org/10.1130/0016-7606(1963)7493:SITCIO2.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGSA Bulletin Search Advanced Search Abstract The concept of major rock-stratigraphic units of interregional scope was introduced in 1948 (Longwell, 1949). It is now possible to restate the concept and to define more explicitly the sequences delimited by interregional unconformities in the continental interior of North America.The sedimentary record of the North American craton from late Precambrian to present is characterized by six major unconformities. These interregional unconformities subdivide the cratonic stratigraphic column into six sequences—major rock-stratigraphic units (of higher than group, megagroup, or supergroup rank) which can be identified, where preserved, in all cratonic interior areas. At the cratonic margins the bounding unconformities tend to disappear in continuous successions, and the cratonic sequences are replaced by others controlled by events in the marginal basins and eugeosynclinal borders.Although the time values of the unconformities vary widely because of differences in degree of nondeposition and amount of erosion, the approximate dates of the regressional maxima represented are: (1) very late Precambrian, (2) early Middle Ordovician, (3) early Middle Devonian, (4) "post-Elvira" Mississippian, (5) early Middle Jurassic, and (6) late Paleocene. A seventh major regression is now in progress. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.