New evidence for geologically instantaneous emplacement of earliest Jurassic Central Atlantic magmatic province basalts on the North American margin

Research Article| September 01, 2000 New evidence for geologically instantaneous emplacement of earliest Jurassic Central Atlantic magmatic province basalts on the North American margin W.E. Hames; W.E. Hames 1Department of Geology and Geography, Auburn University, Auburn, Alabama 36849, USA Search for other works by this author on: GSW Google Scholar P.R. Renne; P.R. Renne 2Berkeley Geochronology Center, 2455 Ridge Road, Berkeley, California 94709, USA, and Department of Earth and Planetary Science, University of California, Berkeley, California 94720, USA Search for other works by this author on: GSW Google Scholar C. Ruppel C. Ruppel 3School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, Georgia 30332-0340, USA Search for other works by this author on: GSW Google Scholar Geology (2000) 28 (9): 859–862. https://doi.org/10.1130/0091-7613(2000)28<859:NEFGIE>2.0.CO;2 Article history received: 13 Mar 2000 rev-recd: 19 Jun 2000 accepted: 29 Jun 2000 first online: 02 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share MailTo Twitter LinkedIn Tools Icon Tools Get Permissions Search Site Citation W.E. Hames, P.R. Renne, C. Ruppel; New evidence for geologically instantaneous emplacement of earliest Jurassic Central Atlantic magmatic province basalts on the North American margin. Geology 2000;; 28 (9): 859–862. doi: https://doi.org/10.1130/0091-7613(2000)28<859:NEFGIE>2.0.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 SocietyGeology Search Advanced Search Abstract Dikes in the southeastern United States represent a major component of the Central Atlantic magmatic province and record kinematics of Pangean breakup near the critical, predrift junction of three major continental masses. Until now, the age of these dikes had not been determined with the same precision as those of Central Atlantic magmatic province basalts on other parts of the circum-Atlantic margin. Our new results for three dike samples from the South Carolina Piedmont yield plateau ages of 198.8 ± 2.2, 199.5 ± 1.8, and 199.7 ± 1.5 Ma. For comparison, we present new age determinations of the benchmark Watchung flows I and III of the Newark basin: 201.0 ± 2.1 and 198.8 ± 2.0 Ma, respectively. Collectively, these data suggest that basaltic volcanism responsible for the dikes, flows, and sills of eastern North America occurred within ∼1 m.y. of 200 Ma. The timing, brief duration, and extent of the Central Atlantic magmatism imply that it may have been causally related to Triassic-Jurassic mass extinctions. The distribution and timing of this magmatism and the absence of regional uplift or an identifiable hotspot track lead us to favor strong lithospheric control on the origin of the Central Atlantic magmatic province, consistent with the modern generation of plume incubation or edge-driven convection models. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.