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

S. Basumallick ¹, B. C. Sarkar ¹, S. Banerjee ²

Affiliations
1 Department of Applied Geology, Indian School of Mines, Dhanbad - 826 004, IN
2 Department of Geology, University of Oklahoma, Norman, US

Abstract

The Upper Proterozoic Lower Bhander Sandstone, occupying a major part of the Tamasa valley at Maihar, has been thought to be deposited in a tidal flat-lagoon complex,in an intertidal to supratidal environment, dominated by ebb and flood tides. A tidal bundle (a medium grained thicker sandstone unit and a thinner siltstone bed) is thought to bear the imprint of velocity and discharge associated with each tidal current as reflected in the thickness of the layers. Thickness data pertaining to 155 tidal bundles recognized in the exposures have been analysed using techniques of Smoothing, Autocorrelation and Fourier filtering, to reveal whether or not any tidal cyclicity existed. The results amply support not only the presence of alternating high spring-neap-low spring semi-lunar cycles, but a dominant periodicity of 32 bundles corresponding to 16 semi-lunar days.

Keywords

Tidal Cyclicity, Sedimentology, Fourier Analysis, Vindhyans, Madhya Pradesh.

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Utpal Bose ¹, A. K. Sharma ², A. Om Kumar ³, S. K. Minda ⁴, S. Banerjee ⁴

Affiliations
1 OSI, NH-5P, Faridabad-121001, IN
2 GSI, Jhalana Dungri, Jaipur-302004, IN
3 GSI, Bandlaguda, Hyderabad-500660, IN
4 Govt. of Rajasthan, Udaipur, IN

Abstract

Felsic volcanics of rhyodacitic composition have recently been recorded in the Late Archaean Berach granite massif underlying the eastern flank of the Hindoli volcano sedimentaries in southeastern Rajasthan. Feldspar-phyric lava flows and lapilli-bearing pyroclastics are the two main volcanic components.

Keywords

Felsic Volcanics, Berach Granite, Hindoli Group, Rajasthan.

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P. K. Saraswati ¹, S. Banerjee ¹

Affiliations
1 IIT Bombay Powai, Murnbai - 400 076, IN

Abstract

No Abstract.

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