Carbon and oxygen isotope systematics of a Paleoproterozoic cap-carbonate sequence from the Sausar Group, Central India Sarada Prasad Mohanty a, ⁎, Arijit Barik a,1 , Sushant Sarangi a , Anindya Sarkar b a Department of Applied Geology, Indian School of Mines, Dhanbad 826004, India b Department of Geology and Geophysics, Indian Institute of Technology, Kharagpur 721302, India abstract article info Article history: Received 13 August 2014 Received in revised form 20 October 2014 Accepted 28 October 2014 Available online 6 November 2014 Keywords: Paleoproterozoic Glaciation Chemostratigraphy Sausar Group India Well-preserved sedimentological features of the Paleoproterozoic age Sausar Group of central India indicate glaciogenic origin for the diamictite in the lower part of the unit. Deglaciation was responsible for a marine transgression and the deposition of proximal glaciomarine facies and a cap-carbonate, followed by fine clastics with manganese ore. Analyses of δ 13 C and δ 18 O contents in the carbonate unit overlying the diamictite, together with Sr and Ba contents and REE data, indicate the preservation of primary geochemical signatures. The average δ 13 C carb content ranges between -3.1‰ and +0.1‰ V-PDB, having peak negative δ 13 C excursions of up to -7.4‰ V-PDB, similar to Paleoproterozoic and Neoproterozoic cap-carbonates elsewhere. High Sr and Ba contents indicate the presence of aragonite and barite precursors, similar to well-studied Neoproterozoic cap- carbonates. A single continuous carbonate unit shows δ 13 C excursions from -4.4 to +2.6‰ V-PDB. The lithological association and chemostratigraphy are comparable with the carbonate–tillite association of the Huronian Supergroup of Canada, the Snowy Pass Supergroup of the USA, the Transvaal Supergroup of South Africa, and the Turee Creek Group of Australia. © 2014 Elsevier B.V. All rights reserved. 1. Introduction Glaciogenic deposits, both modern and ancient, have been stud- ied in detail for 50 years, leading to the recognition of criteria for distinguishing glacial deposits from sediments deposited by other processes (e.g., Aalto, 1971; Young, 1976; Boulton and Deynoux, 1981). A study of the lithological and tectonic evolution of Precambrian glacial deposits and associated sediments has led to the successful correlation of different continental blocks and the reconstruction of Pre- cambrian continental assemblages (Ojakangas, 1988; Young, 1988; Cheney, 1996; Aspler and Chiarenzelli, 1998). Thin dolostone horizons (cap-carbonates), which occur above glacial diamictites and show dis- tinct sedimentological, biological, and textural features, are increasingly used for global correlation and understanding the evolution of the atmosphere and biosphere during the Precambrian (Kaufman and Knoll, 1995; Karhu and Holland, 1996; Bau et al., 1999; Kirschvink et al., 2000; Anbar and Knoll, 2002; Aharon, 2005; Jaffrés et al., 2007; Sekine et al., 2011; Tang et al., 2011). In contrast to the many reported occurrences of Neoproterozoic gla- cial units and cap-carbonates, Paleoproterozoic glaciations are reported from only a few localities in North America (Young and Nesbitt, 1985), Europe (Marmo and Ojakangas, 1984; Strand and Laajoki, 1993), South Africa (Eriksson et al., 1995; Evans et al., 1997), and Australia (Trendall, 1976; Martin, 1999), and cap-carbonates are reported from only a few areas like the Espanola Formation of the Huronian Super- group (Bekker et al., 2005), the Duitschland and Boshoek/Makganyene formations of the Transvaal Supergroup of South Africa (Bekker et al., 2001), and the Meteorite Bore Member of the Turee Creek Group (Martin, 1999; Lindsay and Brasier, 2002). Evidence for Precambrian glaciations in Peninsular India was suspected from the many occurrences of matrix-supported conglomer- ates. Although, many such occurrences lacked either crucial physical features (striations/dropstones) or geochemical proxies of glaciation, evidence of glaciation in the Paleoproterozoic rocks of the Sausar Group of Central India was recorded from the association of diamictites and dropstones in carbonates (Mohanty et al., 2005; Mohanty, 2006). The purpose of the present study is to determine the stable isotope stratigraphy of the cap-carbonate unit of the Sausar Group, and to provide geochemical data for chemostratigraphic correlation of the Paleoproterozoic glaciogenic rocks. 2. Regional geology of the Sausar Group The Precambrian terrains of Peninsular India have in their central part a distinct EW-trending morpho-tectonic unit, the Satpura Mountain Belt, which separates the Bundelkhand block in the north from the Bastar- Dharwar cratons to the south (Fig. 1A). The Sausar Group on the southern flank of the Satpura Mountain Belt comprises metavolcanics and Palaeogeography, Palaeoclimatology, Palaeoecology 417 (2015) 195–209 ⁎ Corresponding author. Tel.: +91 9431122457. E-mail address: mohantysp@yahoo.com (S.P. Mohanty). 1 Present Address: Geological Survey of India, Bhubaneswar. http://dx.doi.org/10.1016/j.palaeo.2014.10.036 0031-0182/© 2014 Elsevier B.V. All rights reserved. Contents lists available at ScienceDirect Palaeogeography, Palaeoclimatology, Palaeoecology journal homepage: www.elsevier.com/locate/palaeo