Journal of Geological Society of India (Online archive from Vol 1 to Vol 78)

K. G. Kulkarni ¹, M. A. Ghare ¹

Affiliations
1 Department of Geology and Palaeontology, M.A.C.S. Research Institute, Pune 411004, IN

Abstract

Ichnofacies of rocks of Jurassic sequence of Wagad, Kutch, are identified on the basis of ichnoassemblages, Wagad Sandstone Formation belongs to shallow Cruziana facies; Washtawa Formation to deeper Cruziana facies; Gangta Member (East) to intermediate Cruziana facies and Gangta Member (West) to Zoophycos facies. The stratigraphic distribution of the ichnoasscmblages indicates regression of the sea from Argovian to Lower Cretaceous.

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K. G. Kulkarni ¹, M. A. Ghare ¹

Affiliations
1 Department of Geology and Palaeontology, M.A.C.S. Pune 411 004, IN

Abstract

Of the seventeen ichnoforms, many are dominantly associated either with fodinichnia or pascichnia. Such an association, suggests low to moderate energy conditions and shallow water environment of deposition. Replacement of Curvolithus by Gyrochorte reflect minor oscillations in sea-level. Facies variations are decipbered by studying percentage distribution of repichnia in relation to other ethological groups.

Keywords

Repichnia, Facies Variations, Jurassic, Trace Fossils, Kutch, Gujarat.

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V. D. Borkar ¹, K. G. kulkarni ¹

Affiliations
1 Department of Geology and Palaeontology, M.A.C.S. Research Institute, Law College Road, Pune 411004, IN

Abstract

Planolites beverleyensis (Billings) Pemberton and Frey is being reported from the Bhaduka Limestone. Wadhwan Formation (Cretaceous) of Kathiawar, Gujarat, wherefrom only one trace fossil. viz., Feddenichnus feddeni Chiplonkar and Borkar was reported. Bryozoa from the Bhaduka Limestone ascribe a palaeoenvironment suitable to suspension feeders. However. Planolites along with Feddenichnus suggests palaeoenvironment congenial to infaunal deposit feeders.

Keywords

Bhaduka Formation, Cretaceous, Kathiawar, Trace Fossils, Gujarat.

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K. G. Kulkarni ¹, V. D. Borkar ¹

Affiliations
1 Geology and Palaeontology Group, Agharkar Research Institute, Agarkar Road, Pune-411 004, IN

Abstract

A trace fossil occurring in an unusual and peculiar way was found in the upper Bhander Sandstone (Bhander Group, Vindhyan Supergroup) from near Sagoni, district Damoh, Madhya Pradesh. It is an unbranched, smooth, meandering trail, preserved in negative epirelief on the upper surface of a ripple marked sandstone. Individual trails, preserved within nineteen consecutive troughs without crossing crests anywhere, are restricted to only one of the flanks of the ripples. Trail-bearing flanks are on one and the same side of their respective troughs. This trail, identified as Cochlichnus Hitchcock is assigned a Vendian age.

Keywords

Trace Fossil, Cochlichnus Hitchcock, Bhander Group, Vindhyan Supergroup, Vendian, Madhya Pradesh.

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K. G. Kulkarni ¹, V. D. Borkar ¹

Affiliations
1 Geology and Palaeontology Group, Division of Animal Sciences, Agharkar Research Institute, G.G.Agarkar Road, Pune-411004, IN

Abstract

Horizontally disposed, curved to gently sinuous, unbranched burrows, with a thin but distinct lining, are found at village Mardi Shivapur, Belgaum district, Karnataka State. They occur In the Yadha lll Formation, Lokapur Subgroup, Bagalkot Group, Kaladgi Supergroup. On the basis of presence of thin wall and fairly uniform diameter, these burrows are identified as Palaeophycus tubularis, Hall. Draping of later burrows over earlier ones and downward deflection of sediment laminae due to bioturbation provide evidences for their biogenic origin. In view of the radiometric dates of the Kaladgl rocks, these burrows are assigned a mid-Riphean age. This not only sets the lower limit ofthe range ofthe ichnogenus Palaeophycus at mid-Riphean, but also supports the view of Glaessner that the metazoans appeard some 1000 m.y. ago, much earlier than the Ediacaran period.

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