Middle Eocene Ostracoda from the Tadkeshwar Lignite Mine, Cambay Basin, Gujarat

Abstract

Previous work on the fauna and flora of the Cambay shale underlying as well as inter-bedded within the lignite seams of Vastan lignite mine, Gujarat allows the shale to be assigned a Lower Eocene age. However, there is no record of occurrence of any fossil from the sedimentary beds succeeding the shale-lignite sequence that might fix upper age limit of the Cambay shale. We record a characteristic Middle Eocene ostracod assemblage from the Nummulitic marl/limestone, immediately overlying the shale-lignite sequence from the Tadkeshwar lignite mine close to the Vastan lignite mine. The assemblage comprises 22 species, many of which widely occur in the Middle Eocene beds of Kachchh, Rajasthan and adjacent areas of Pakistan.

Pyrolysis Results of Shales from the South Cambay Basin, India: Implications for Gas Generation Potential

“…The Tadkeshwar Formation begins with grey clay-bed which is overlain by the carbonaceous clay-bed, which, in turn, is conformably overlain by a fivemeter-thick lignite seam, a marker bed (Singh, 2012). Based on relative stratigraphic position, depositional environment and occurrence of paleo-fauna of the lignite sequences, it has been considered analogous to the Cambay Formation ( (Singh et al, 2012;2012 b;Sahni et al, 2006;Nagori et al, 2013;Rust et al, 2010). The predominance of mud rich sediments together with lignites and siderites in the Tadkeshwar and Rajpardi mines suggest deposition in low energy near shore coastal setting (Rust et al, 2010).…”

“…The shale samples have been collected from the open cast mines, namely Tadkeshwar and Rajpardi in Surat, Bharuch districts, respectively (Fig.1). The fossil biotas recovered from the sedimentary sequences exposed in these mines suggest an analogy of Cambay shales for these shale horizons (Singh et al, 2012 a;2012b;Sahni et al, 2006;Nagori et al, 2013). Cambay shale is an established prolific hydrocarbon source rock in the basin.…”

“…Rock-Eval pyrolysis is one of the most basic organic geochemical methods to study these parameters. In the present study, the interbedded shale formations within the middle Eocene lignite sequences, referred to as Cambay Formation, (Nagori et al, 2013), of the Tadkeshwar and Rajpardi mines in Surat and Bharuch districts, respectively, have been sampled to study the organic matter properties using Rock-Eval pyrolysis. The sedimentary sequences exposed in the mines show the shales to be high in Total Organic Carbon (TOC) content, ranging between 0.2% to 47.3%.…”

Early Eocene equatorial vegetation and depositional environment: Biomarker and palynological evidences from a lignite-bearing sequence of Cambay Basin, western India

“…The luxuriant vegetation resulted into the deposition of brown coal or lignite successions along the northwestern margins of the Indian plate. Equivalent Early Palaeogene coal seams have been reported from Trans-Indus Range in Pakistan (Nagori et al, 2013). In India these Palaeogene lignite-bearing horizons are exposed in several mine sections from Jammu and Kasmir (Kalakot coalfields), in the north to Gujarat (lignite mines of Kutch and Cambay Basin), in the west via Rajasthan (lignite mines of Rajasthan Basin) and Meghalaya in NE ( Fig.…”

“…Presently, large scale mining activities on the Palaeogene lignite successions in Cambay and its adjacent Kutch Basin for the production of thermal power give an opportunity to focus on these subsurface strata. Among them Vastan, Tadkeswar and Rajpardi lignite mines in Cambay Basin and Matanomadh and Panandhro lignite mines of Kutch Basin have been studied extensively for providing valuable information about the age and contemporary flora and fauna (Dutta et al, 2009(Dutta et al, , 2011aNagori et al, 2013;Rana et al, 2004;Samant and Phadtare, 1997;Samant and Tapaswi, 2001;Saraswati et al, 2014) (Fig. 2).…”