Constraints on the development of Proterozoic basins in central India from 40Ar/39Ar analysis of authigenic glauconitic minerals

Research Article| January 01, 2011 Constraints on the development of Proterozoic basins in central India from 40Ar/39Ar analysis of authigenic glauconitic minerals James E. Conrad; James E. Conrad † 1U.S. Geological Survey, MS-999, Menlo Park, California 94025, USA †E-mail: jconrad@usgs.gov Search for other works by this author on: GSW Google Scholar James R. Hein; James R. Hein 1U.S. Geological Survey, MS-999, Menlo Park, California 94025, USA Search for other works by this author on: GSW Google Scholar Asru K. Chaudhuri; Asru K. Chaudhuri 2Department of Geology, Presidency College, 86/1 College Street, Kolkata 700073, India Search for other works by this author on: GSW Google Scholar Sarbani Patranabis-Deb; Sarbani Patranabis-Deb 3Geological Studies Unit, Indian Statistical Institute, 203 B.T. Road, Kolkata 700108, India Search for other works by this author on: GSW Google Scholar Joydip Mukhopadhyay; Joydip Mukhopadhyay 2Department of Geology, Presidency College, 86/1 College Street, Kolkata 700073, India Search for other works by this author on: GSW Google Scholar Gautam Kumar Deb; Gautam Kumar Deb 4Department of Geology, Durgapur Government College, Durgapur 713214, India Search for other works by this author on: GSW Google Scholar Nicolas J. Beukes Nicolas J. Beukes 5Department of Geology, University of Johannesburg, APK Campus, 2006 Auckland Park, South Africa Search for other works by this author on: GSW Google Scholar Author and Article Information James E. Conrad † 1U.S. Geological Survey, MS-999, Menlo Park, California 94025, USA James R. Hein 1U.S. Geological Survey, MS-999, Menlo Park, California 94025, USA Asru K. Chaudhuri 2Department of Geology, Presidency College, 86/1 College Street, Kolkata 700073, India Sarbani Patranabis-Deb 3Geological Studies Unit, Indian Statistical Institute, 203 B.T. Road, Kolkata 700108, India Joydip Mukhopadhyay 2Department of Geology, Presidency College, 86/1 College Street, Kolkata 700073, India Gautam Kumar Deb 4Department of Geology, Durgapur Government College, Durgapur 713214, India Nicolas J. Beukes 5Department of Geology, University of Johannesburg, APK Campus, 2006 Auckland Park, South Africa †E-mail: jconrad@usgs.gov Publisher: Geological Society of America Received: 01 May 2009 Revision Received: 11 Nov 2009 Accepted: 21 Nov 2009 First Online: 08 Mar 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 © 2011 Geological Society of America GSA Bulletin (2011) 123 (1-2): 158–167. https://doi.org/10.1130/B30083.1 Article history Received: 01 May 2009 Revision Received: 11 Nov 2009 Accepted: 21 Nov 2009 First Online: 08 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation James E. Conrad, James R. Hein, Asru K. Chaudhuri, Sarbani Patranabis-Deb, Joydip Mukhopadhyay, Gautam Kumar Deb, Nicolas J. Beukes; Constraints on the development of Proterozoic basins in central India from 40Ar/39Ar analysis of authigenic glauconitic minerals. GSA Bulletin 2011;; 123 (1-2): 158–167. doi: https://doi.org/10.1130/B30083.1 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 Ages of some key stratigraphic sequences in central Indian Proterozoic basins are based predominantly on lithostratigraphic relationships that have been constrained by only a few radioisotopic dates. To help improve age constraints, single grains of glauconitic minerals taken from sandstone and limestone in two Proterozoic sequences in the Pranhita-Godavari Valley and the Chattisgarh basin were analyzed by the 40Ar/39Ar incremental heating method. Analysis of the age spectra distinguishes between ages that are interpreted to reflect the time of glauconite formation, and anomalous ages that result from inherited argon or postcrystallization heating. The analyses indicate an age of 1686 ± 6 Ma for the Pandikunta Limestone and 1566 ± 6 Ma for the Ramgundam Sandstone, two units in the western belt of Proterozoic sequences in Pranhita-Godavari Valley. Glauconite from the Chanda Limestone, in the upper part of this sequence, contains inherited 40Ar but is interpreted to reflect an age of ca. 1200 Ma. Glauconite from the Somanpalli Group in the eastern belt of the Pranhita-Godavari Valley gives an age of 1620 ± 6 Ma. In the Chattisgarh basin, glauconite from two units gives disturbed ages that suggest a period of regional heating in the Chattisgarh basin at ca. 960–1000 Ma. These new ages indicate that these sequences are 200–400 m.y. older than previously recognized, which has important implications for geochemical studies of Mesoproterozoic ocean redox conditions in addition to providing important constraints on regional tectonics and lithostratigraphy. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.