of the Singhora-Saraipali area, south-eastern Chattisgarh Basin - fieldi

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dominated formation contains intraformational conglomerate beds, exposed at Bamhanpuri (21º35'45.2"N; 83º56'42.3"E). Formation E: It consist of brown shale, and subordinate sandstone and stromatolitic limestone and is best exposed at Beladula (21º34'37.0"N; 82º50'26.7"E) and near Gangori (21º37'00.0"N; 82º52'50.0"E). The brown shale overlies the limestone of formation D through a narrow transition zone of shale-limestone intercalations. Stromatolitic bioherms occur within this calcareous shale, which is best exposed at Pikri (21º35'45.0"N; 82º57'30.0"E). The bioherms are characterised by branching columnar stromatolites. Correlation Our mapping does not reveal any clear evidence for any unconformity, such as major erosional surface, discordance of dip and basal conglomerates within the succession. The sections at Kesratal (21º16'05.9"N; 83º05'33.6"E) and Bhagat Saraipali (21º22'30.6"N; 83º11'23.9"E) along the Sishupal and Gomarda hills, respectively, consists of impersistent granules and pebble (0.5 to 2 cm) layers (15-25 cm thick) at different levels. Those may be indicator of sea level fall and/or episodic storm events(Leithold and Bourgeois, 1984; Sloss, 1984). Such pebble beds within the succession do not imply any major hiatus that can be considered as sequence bounding unconformity. The sedimentary succession in the study area, from formation A to formation E represents a continuous succession without any major hiatus (fig.3). From the present mapping, it has been established that formation A can be physically mapped along the strike into Lohardih Formation as defined in Damdama and adjoining areas (Patranabis-Deb, 2004; Patranabis-Deb and Chaudhuri, 2008), a 9
few kilometres to the north of the Singhora-Saraipali transect. The lithology and lithological organisation of formation A is identical with that of the Lohardih Formation. Formation A grades upward to the mud-dominated succession of formation B, which is physically continuous with the Gomarda Formation of Patranabis-Deb (2004) and Patranabis-Deb and Chaudhuri (2008). The Saraipali and Chhuipali Formations of Das et al. (2003) represent the MDS 1 and MDS 2 respectively, whereas the Bhalukona Formation represents the thick sandstone (SS) in this present study. The high degree of lithological similarity between MDS 1 and MDS 2, and their amalgamation into a single mud dominant succession where the sandstone (SS) pinches out is a compelling argument to group them into a single formation, which we designate as the Gomarda Formation. The Bhalukona Formation (SS) of Das et al. (2003) has been ranked as a member, which occurs as a lens within Gomarda Formation (NACSN, 1983), similar to the Daihan Sandstone Member (Patranabis-Deb and Chaudhuri, 2008). The stratigraphical position, lithological characteristics and the facies assemblages of the formation C are similar to that of the Kansapathar Formation and designated as the Kansapathar Formation. The formations D and E conformably overlie the Kansapathar Formation, and are correlatable with the Charmuria Formation or Sarangarh Formation and Gunderdehi Shale of the Raipur Group respectively. 10
Page 1 and 2: Veiw on the lithostratigraphy of th
Page 3 and 4: Contents Introduction…………
Page 5 and 6: 2002 and Patranabis-Deb & Chaudhuri
Page 7 and 8: evaluate the lithostratigraphy of t
Page 9: Stromatolite bioherms occur in the
Page 14 and 15: References:- Basu, A., Patranabis-D
Page 16: Patranabis-Deb, S. and Chaudhuri, A

of the Singhora-Saraipali area, south-eastern Chattisgarh Basin - fieldi

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