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

Rahul Mohan ¹, Abhay Kumar Singh ², Jayant K. Tripathi ², G. C. Chowdhary ¹

Affiliations
1 Department of Geology, Banaras Hindu University, Varanasi - 221005, IN
2 School of Environmental Sciences, Jawaharlal Nehru University, New Delhi -110 067, IN

Abstract

The chemical characteristics of groundwater in and around the industrial area of Naini district, Allahabad have been studied to evaluate the suitability of water for irrigation and domestic uses. Sixty five water samples representing the shallow and deep groundwater of the area were collected and analysed for pH, EC, TDS, HCO₃, CO₃, SO₄, Cl, Ca, Mg, Na and K. It is observed that the quality of the groundwater is suitable for domestic use with some exception. The observed high quantity of heavy metals at some sites requires immediate attention and detailed study. The calculated values of SAR, RSC and sodium percentage indicate the good to permissible quality of water. However, the high sodium percentage and RSC values at certain sites restrict its suitability for agricultural purposes.

Keywords

Hydrochemistry, Pollution, Sodium Adsorption Ratio, Residual Sodium Carbonate, Trace Metals, Naini Industrial Area, Uttar Pradesh.

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Rahul Mohan ¹

Affiliations
1 Micropalaeontology and Marine Geology Lab, Department of Geology, Banaras Hindu University, Varanasi - 221 005, IN

Abstract

No Abstract.

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Rahul Mohan ¹, M. V. S. Guptha ²

Affiliations
1 National Centre for Antarctic & Ocean Research, Department of Ocean Development, Government of India, Headland Sada, Goa - 403 804, IN
2 National Institute of Oceanography, Dona Paula, Goa - 403 004, IN

Abstract

Planktic foraminiferal studies from the southern Bay of Bengal (SBBT) indicate the presence of corroded specimens of Globorotalia menardii in the deep trap at a depth of 3011 rn during February-March 1992. Strangely, all the other spinose and less resistant spinose foraminiferal species are found devoid of any signs of dissolution in association with the highly corroded specimens of Grmenardii. In view of the above and also to the fact that this trap depth is well above the lysocline, it is postulated that these corroded specimens of Grmenardii tests could have been supplied by lateral advection and mixed up with the settling particles at SBBT, thus this assemblage is a resultant of two different sources, during this particular period.

Keywords

Planktic Foraminifera, Corrosion, Lateral advection, Sediment trap, Bay of Bengal.

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Rahul Mohan ¹

Affiliations
1 National Centre for Antarctic & Ocean Research Headland Sada, Goa - 403 804, IN

Abstract

No Abstract.

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Rahul Mohan ¹, Ratan Kar ²

Affiliations
1 NCAOR, Goa, IN
2 BSIP, Lucknow, IN

Abstract

No Abstract.

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Manish Tiwari ¹, Rasik Ravindra ¹, Rahul Mohan ¹

Affiliations
1 NCAOR, Goa, IN

Abstract

No Abstract.

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Rasik Ravindra ¹, Rahul Mohan ¹

Affiliations
1 National Centre for Antarctic and Ocean Research, Headland Sada, Vasco-da-Gama, Goa - 403 804, IN

Abstract

No Abstract.

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Rahul Mohan ¹, Sunil Kumar Shukla ¹, Shramik M. Patil ¹, Suhas S. Shetye ¹, Karima K. Kerkar ¹

Affiliations
1 National Centre for Antarctic and Ocean Research, Headland Sada, Vasco-da-Gama, Goa – 403 804, IN

Abstract

Diatoms from surface sediment samples collected from Enderby Basin of Indian Sector of Southern Ocean were analyzed to determine the relative abundance and distribution of seven key indicator diatom species viz. Sea ice related species Fragilariopsis rhombica, F. separanda, F. curta, F. ritscheri, Thalassiosira tumida and Actinocyclus actinochilus and Open Ocean species F. kerguelensis on the basis of modern physico-chemical parameters. The relative abundances of different species observed viz. F. rhombica - 6.25%; F. separanda - 12.5%; F. curta - 10.53-13.33%; F. ritscheri - 4.55-12.5%; F. kerguelensis - 6.25-63.64%; T. tumida - 3.13% and A. actinochilus - 9.38-13.33%. The increasing abundance of F. kerguelensis consecutively suggests the effect of Antarctic bottom water in the study area which is further substantiated by the presence and increasing abundance of F. ritscheri. The gradual decrease in abundance or absence of sea ice related species from the sampled stations indicates the summer and winter sea ice extent concentration in the study area. The nutrient concentration correlates with the distribution and abundances of diatom species.

Keywords

Diatom, Surface Sediment, Distribution and Abundance, Physico-Chemical Parameter, Enderby Basin, Indian Sector, Southern Ocean.

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