A B C D E F G H I J K L M N O P Q R S T U V W X Y Z All
Achyuthan, Hema
- Basin Modelling Course, June 6 to June 10, 2000
Authors
1 Centre for Geoscience and Engineering, Anna University, Chennai 600 025, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 56, No 3 (2000), Pagination: 340-340Abstract
No Abstract.- Mineralogy and Isotopic Composition of Pyrites-Bearing Ejects from a Mud Volcano, Baratang, Andaman Islands
Authors
1 Department of Geology, Anna University, Chennai-600025, India, IN
2 Department of Geosciences, University of Arizona, Tucson, Arizona-85721, US
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 53, No 3 (1999), Pagination: 329-334Abstract
The Jarawa Creek mud volcano on Baratang Island has produced a variety of ejecta including mud containing illite, kaolinite and microfossils, volcanic glass, brine, methane gas and sulfide nodules. The nodules are of pyrite with a δ34S ranging from -3.6 to 25.4‰. Sulfate leached from the mud has δ34S values of -9.3 and -11.37‰. Our study reveals that the sulfate could not have been derived either from the nodules themselves or from the sea water or from connate brine. The nodules are of sedimentary origin and the most likely source of sulfate is sedimentary sulfide implying subsurface oxidation and a supply of oxidant possibly in groundwater.Keywords
Mineralogy, Isotopic Studies, Sulfur Isotope, Pyrite, Mud Volcano, Baratang, Andaman Islands.- Mineral Replacement of Plant Roots in Fluvial Sediments of the Link Channel of Krishna River, Near Yedurwadi, Belgaum District, Karnataka
Authors
1 Department of Geology, Anna University, Chennai 600 025, IN
2 Department of Archaeology, Deccan College, Pune 411 006, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 50, No 6 (1997), Pagination: 765-768Abstract
Micromorphology, XRD analyses and SEM studies of rhizoliths from Late Middle Pleistocene yellowish brown silty fluvial sediments of Yedurwadi reveal that calcium carbonate has a localized source. Silica and calcium carbonate are formed by the plant ischolar_mains through their metabolic activity creating a favourable microenvironment for the processes of SiO2 and CaCO3 precipitation and replacement.Keywords
Sedimentology, Karnataka.- Pozzolanic Characteristics of Young Toba Tuff
Authors
1 Department of Geology, Anna University, Chennai 600 025, IN
2 Department of Civil Engineering, Indian Institute of Technology Madras, Chennai 600 036, IN
Source
Current Science, Vol 109, No 10 (2015), Pagination: 1869-1874Abstract
Portland Pozzolana Cement (PPC) is widely used to achieve durable and sustainable concrete in modern construction. In the present study, the potential use of natural volcanic ash in the manufacturing of PPC has been studied. Young Toba Tuff (YTT) was collected from Jwalapuram, Andhra Pradesh, India. The pozzolanic performance of this ash was assessed by Strength Activity Index (SAI) and Frattini test. SAI of YTT was found to be above 75% for sufficient pozzolanicity. Further, the results of Frattini test were below the lime solubility curve, indicating that YTT could be potentially useful as pozzolanic material in concrete.Keywords
Concrete, Pozzolanic Characteristics, Strength Activity Index, Volcanic Ash.References
- Petraglia, M. et al., Middle Paleolithic assemblages from the Indian subcontinent before and after the Toba super-eruption. Science, 2007, 317, 114–116.
- Fisher, R. V. and Schmincke, H. V., Pyroclastic Rocks, Springer, Berlin, 1984, p. 472.
- Williams, M., The ∼73 ka Toba super-eruption and its impact: history of a debate. Quaternary Int., 2012, 258, 19–29.
- Dutta, M. and Mukherjee, S., An outlook into energy consumption in large scale industries in India: the cases of steel, aluminium and cement. Energy Policy, 2010, 38, 7286–7298.
- Malhotra, V. M. and Kumar Mehta, P., Pozzolanic and Cementitious Materials, Gordon and Breach Science Publishers, Amsterdam, 1996.
- Antiohos, S. and Tsimas, S., Investigating the role of reactive silica in the hydration mechanisms of high-calcium fly ash/cement systems. Cem. Concr. Compos., 2005, 27, 171–181.
- Rahhal, V. and Talero, R., Calorimetry of Portland cement with silica fume, diatomite and quartz additions. Constr. Build. Mater., 2009, 23, 3367–3374.
- Tironi, A., Trezza, M. A., Scian, A. N. and Irassar, E. F., Assessment of pozzolanic activity of different calcined clays. Cem. Concr. Compos., 2013, 37, 319–327.
- Bendapudi, S. C. K. and Saha, P., Contribution of fly ash to the properties of mortar and concrete. Int. J. Earth Sci. Eng., 2011, 4, 1017–1023.
- Habert, G., Choupay, N., Escadeillas, G., Guillaume, D. and Montel, J. M., Clay content of argillite: influence on cement based mortars. Appl. Clay Sci., 2009, 43, 322–330.
- Schulz, H., Emeis, K. C., Erlenkeuser, H., Von Rad, U. and Rolf, C., The Toba volcanic event and interstadial/stadial climates at the marine isotopic stage 5 to 4 transition in the Northern Indian Ocean. Quaternary Res., 2002, 57, 22–31.
- Acharya, S. K. and Basu, P. C., Toba ash in the Indian subcontinent and its implications for correlation of late Pleistocene alluvium. Quaternary Res., 1993, 40, 10–19.
- Chesner, C. A., Petrogenesis of the Toba Tuffs, Sumatra, Indonesia. J. Petrol., 1998, 39, 397–438.
- Jones, M. T., Sparks, R. S. J. and Valdes, P. J., The climatic impact of super volcanic ash blankets. Climate Dyn., 2007, 29, 553–564.
- Haslam, M. et al., A southern Indian Middle Palaeolithic occupation surface sealed by the 74 ka Toba eruption: further evidence from Jwalapuram Locality 22. Quaternary Int., 2012, 258, 148–164.
- Raj, R., Occurrence of volcanic ash in the Quaternary alluvial deposits, lower Narmada basin, western India. J. Earth Syst. Sci., 2008, 117, 41–48.
- Down, M. J., Master, R. W., Streckeisen, A. and Zanetti, B., A chemical classification of volcanic rocks based on the total alkali–silica diagram. J. Petrol., 1986, 27(3), 745–750.
- IS: 1727, Indian standard specification for methods of test for pozzolanic materials. Bureau of Indian Standards, New Delhi, 1967.
- IS 3812, Indian standard specification for fly ash for use as pozzolana and admixtures. Bureau of Indian Standards, New Delhi, 1981.
- ASTM C311, Standard specification for sampling and testing fly ash or natural pozzolans for use in Portland-Cement Concrete, ASTM, USA, 2002.
- BS EN 196(5), Standard specification for testing cement – Pozzolanicity tests for pozzolanic cement, BSI, London, 2005.
- Donatello, S., Tyrer, M. and Cheeseman, C. R., Comparison of test methods to assess pozzolanic activity. Cem. Concr. Compos., 2010, 32, 121–127.
- ASTM C618, Standard specification for coal fly ash and raw or calcined natural pozzolan for use in concrete, ASTM, USA, 2003.
- Frias, M., Villar-cocin, E. and Valencia-Morales, E., Characterisation of sugar cane straw waste as pozzolanic material for construction, calcining temperature and kinetic parameters. Waste Manage., 2007, 27, 533–538.
- Hamidi, M., Kacimi, L., Cyr, M. and Clastres, P., Evaluation and improvement of pozzolanic activity of andesite for its use in eco-efficient cement. Constr. Build. Mater., 2013, 47, 1268–1277.
- Tironi, A., Trezza, M. A., Scian, A. N. and Irassar, E. F., Kaolinitic calcined clays: factors affecting its performance as pozzolans. Constr. Build. Mater., 2012, 28, 276–281.
- Janotka, I., Puertas, F., Palacios, M., Kuliffayová, M. and Varga, C., Metakaolin sand-blended-cement pastes: rheology, hydration process and mechanical properties. Constr. Build. Mater., 2010, 24, 791–824.
- Middle to Late Holocene Palaeoenvironmental Changes: Evidence from the Sediments, Pollen and Radiocarbon Dates, Adyar, Chennai
Authors
1 Birbal Sahni Institute of Palaeobatany, 53, University Road, Lucknow - 226 020, IN
2 Centre for Geoscience and Engineering, Anna University, Chennai - 600 090, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 68, No 2 (2006), Pagination: 230-238Abstract
In this paper, we present Middle to Late Holocene chronostratigraphy and palynology data analyzed from three insitu cores - sedimentary profiles retrieved along the Adyar river and the Adyar estuary zone, Chennai. These cores offered excellent cross-sections along the east - west direction. Our data reveals that the mangrove vegetation that existed until Middle Holocene (4180 ±130 Yrs. BP) became extinct since the Late Holocene. The tidal influx influenced the estuary 10 km west inland (at Saidapet) from the present shoreline until Middle Holocene providing congenial environment for mangroves. The reasons for decline in mangroves since the Late Holocene (last 2000 Yrs. BP) is attributed to the relative sea level and coastal configuration change enhanced by the anthropogenic pressure. The palynological evidences from Saidapet (Chennai) and Sulurpet (playa of the Pulicat lagoon) indicate the transgressive phase of middle Holocene in Palar Delta. Although mangroves were abundant during Middle Holocene in both the areas, it faced complete extinction or acutc degradation since the Late Holocene.Keywords
Palynology, Estuarine Sediments, Mangroves, Late Holocene, Coastal changes, Radiocarbon dates, Adyar, Chennai, Tamil Nadu.- Sediment Characteristics and Depositional Environment of Silica Sand Deposits of the East Coast, Tamil Nadu
Authors
1 Department of Geology, Anna University, Chennai - 600 025, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 71, No 3 (2008), Pagination: 337-344Abstract
Silica sand deposits are exposed along the East Coast, Tamil Nadu, nearly 80 km south of Chennai. The original sediment is quartz sand to feldspathic quartz sand Soil has developed over the younger deposits. Trough cross bedding is well developed in the younger sediments. Textural analyses of silica sand were carried out for compatative study.Silica sand varies from very coarse sand (-0.25φ to 0.5φ), medium sand (1.25φ to 2φ) fine sand (2.25φ to 3φ), very fine sand (3.25φ to 4φ) and coarse silt (4.06φ to 5φ). Fine to medium sized grains are dominant in the silica sand. The silica sand is poorly sorted, fine skewed, leptokurtic to platykurtic in characteiistics. Beach and dune sediments are predominandy coarse sand with heavy minerals. The dune sediments are moderately to well sorted, fine skewed, and leptokurtic. The beach sediments are well sorted strongly coarse skewed, and platy to leptokurtic. The sphericity and roundness values of the silica sands vary from rounded to sub rounded and are very equant. The various types of surface features are 'V shaped notches, conchoidal fractures and striations The study shows that the depositional environment of silica sand is markedly different from the aeolian and beach enviionment Bivariant plots and textural analyses of the silica sands indicate that they have been primarily deposited by fiuvial action.
Keywords
Silica Sand, Textural Analyses, Bivariant Plots, SEM Studies, Fluvial Origin, Tamil Nadu.- Tafoni along the East Coast, Chennai to Mamallapuram, Tamil Nadu
Authors
1 Department of Geology, Anna University, Chennai 600 025, IN
Source
Current Science, Vol 109, No 1 (2015), Pagination: 195-201Abstract
A study on weathering pits called tafoni was carried out on rock surfaces that age from a few hundreds to millions of years along the east coast between Chennai and Mamallapuram. Tafoni of varying sizes and shapes such as simple circular dots to oblate to prolate, hemispherical to spherical are formed on the granite, granite gneiss, charnockites (acid and mafic) and sandstone both on exposed and inner wall surfaces. In this study, their formation is related to not only tropical weathering processes, but also to sea salt water splays causing salt mineral etching, weathering processes, besides microbial activity, algal and lichen growth accentuating their formation.Keywords
Bedrock Surface, Mafic Minerals, Tafoni, Weathering Processes.- Quaternary Stratigraphy of the Koratallaiyar-Cooum Basin, Chennai
Authors
1 Department of Geology, Anna University, Chennai - 600 025, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 73, No 5 (2009), Pagination: 683-696Abstract
In this paper we present Quaternary stratigraphy of the area around Chennai based on archaeological findings on the ferricrete surface, geomorphological observations supplemented by radiocarbon dating. The coastal landscape around Chennai, Tamil Nadu, has preserved ferruginised boulder gravel deposits, ferricretes and fluvial deposits of varying thickness. The area studied is approximately 150 km east to west and 180 km north to south with a broad continental shelf towards the seaward. Several rivers enter the Bay of Bengal along its shores like the Koratallaiyar, Cooum and the Adyar. Precambrian charnockite and Upper Gondwana sandstone and shale bedrock rim the shelf margin. For the most part, the Upper Pleistocene-Holocene fluvial sediments overlie an erosion surface that has cut into older Pleistocene sediments and ferricrete surface. Incised valleys that cut into this erosion surface are up to 5-6 km wide and have a relief of at least 30 m. The largest valley is that cut by the Koratallaiyar River. Holocene sediments deposited in the incised valleys include fluvial gravels, early transgressive channel sands and floodplain silts. Older Pleistocene sediments are deposited before and during the 120-ka high stand (Marine isotope stage 5). They consist of ferricretes and ferricrete gravel formed in nearshore humid environments. Muddy and sandy clastic sediments dated to the ca. 5 ka highstand suggest that the climate was semi arid at this time with less fluvial transport. The coarsening up sequence indicates deposition by high intensity channel processes. Pedogenic mottled, clayey silt unit represents an important tectonic event when the channel was temporarily drained and sediment were sub aerially exposed. Uplift of the region has caused the local rivers to incise into the landscape, forming degradation terraces.Keywords
Quaternary Stratigraphy, Boulder Gravel Bed, Ferricretes, Holocene Fluvial Sediments, Geoarchaeology, Chennai.References
- ACHYUTHAN, H. (1993) Processes of ferricritisation and Quaternary sea level changes in the East Coast around Madras, Tamil Nadu. Paper presented at the workshop 'On Evolution of East Coast of India', April 18-20, Tamil University, Tanjore, pp.35-36.
- ACHYUTHAN, H. (1996) Geomorphic evolution and genesis of laterites around the East Coast of Madras, Tamil Nadu. Geomorphology, v.16, pp.71-76.
- ACHYUTHAN, H., RAMASUBRAMANIYAM, S. and NAGALAKSHMI, T. (2000) Formation of Red Soils around Chennai, Tamil Nadu, India. The Indian Geograph. Jour., v.75, pp.17-36.
- BANERJEE. K.D. (1957-1979) Excavation Report ASI Journals. New Delhi.
- BOURMAN, R.P. (1993a) Perennial problems in the study of laterite: a review. Jour. Earth Sci., v.40, pp.387-401.
- BOURMAN, R.P. (1993b) Modes of ferricrete genesis: Evidence from SE Australia. Zeitschrift Fur Geomorph., v.37, pp.77-101.
- BOURMAN, R.P., MILNESA.R. and OADES, J.M. (1987) Investigations of ferricretes and related surficial ferruginous materials in parts of southern and eastern Australia. Zeitschrift Fur Geomorph., v.64, pp.1-24.
- BULL, W.B. (1985) Alluvial fan deposits in western Fresno County, California. In: T.H. Nilsen (Ed.), Modern and Ancient alluvial fan deposits. Van Nostrand Reinhold and Company, New York, pp.86-95.
- FEDEROFF, N. (1979) Organization du solal echelle microscopique. In: M. Bonneau and B. Sohchier (Eds.), Pedologie: Paris, Mason, pp.251-265.
- FOOTE, R.B. (1866) On the occurrence of stone implements in lateritic formations in various parts of the Madras and north Arcot Districts, Madras. Jour. Literature and Sciences 3rd Series, Part II: 1-35, with an appendix by W. King, pp.36-42.
- FOOTE, R.B. (1868) On the distribution of stone implements in Southern India. Quart. Jour. Geol. Surv., v.24, pp.484-495.
- GLOPPEN, J.G. and STEEL, R.J. (1985) The deposits, internal structure and geometry in six alluvial fan-fan delta bodies (Devonian-Norway). A study of the significance of bedding sequences in conglomerates. In: T.H. Nielsen (Ed.), Modern and Ancient Alluvial fan deposits, Van Nostrand Reinhold and Company, New York, pp. 313-335.
- GOUDIE, A.S. (1973) Duricrusts in Tropical and sub-tropical landscape. Clarendon Press, Oxford.
- KRISHNASWAMI, V.D. (1938) Environmental and cultural changes of Prehistoric Man near Madras. Jour. Madras Geographic Assoc., v.13, pp.58-90.
- LAL, S.B. (1973) Geochronology of lateritization. In: A. Ghosh and D.P. Agrawal (Eds.), Radiocarbon and Indian Archaeology. Tata Institute of Fundamental Research, Bombay, pp.435-445.
- MIALL, A.D. (1978) Lithofacies types and vertical profile models in braided rivers: A summary. Canadian Soc. Petrol. Geol., v.6, pp.597-604.
- MOHINDRA R., PRAKASH, B. and PRASAD, J. (1992) Historical geomorphology and pedology of the Gandak megafan, the Middle Gangetic Plains, India. Earth Surface Process and Landforms, v.17, pp.643-662.
- MURALIDHARAN. P.K., PRABHAKAR, A. and KUMARGURU, P. (1993) Geomorphology and evolution of the Palar basin. Paper presented at the workshop on 'Evolution of East Coast of India', April 18-20, Tamil University, Tanjore.
- NAGALAKSHMI, T. (2003) Studies on Quatewrnary Stratigraphy and palaeoenvironments between Palar and Koratallaiyar River basin, Chennai, Tamil Nadu. Ph.D. thesis, Anna Unviersity, Chennai.
- NAGALAKSHMI, T. and ACHYUTHAN, H. (2004) Radiocarbon dating and Holocene episodes of alluvial sediemtnation in the Koratallaiyar-Cooum river basin, Chennai. Jour. Geol. Soc. India, v.64, pp.461-469.
- OLLIER, C.D. and GALLOWAY, K.W. (1990) The laterite profile, ferricrete and unconformity. Catena, v.17, pp.97-109.
- PAPPU, S. (1996) Reinvestigation of the prehistoric archaeological record in the Koratallaiyar basin, Tamil Nadu. Man and Environ., v.19, pp.1-23.
- PAPPU, S. (2001) Middle Paleolithic stone tool technology in the Koratallaiyar Basin, South India. Antiquity, v.75, pp.107-117.
- RAJAGURU, S.N., DEODHAR, H. and GHATE, S. (1993) Changes in physical environment of western India during the last 200Ka: A Geoarchaeological Approach. In: Proceedings of the International Symposium on Global Climatic Change (IGBP) held between 27-29 March 1992, Waseda University, Shinjuku, Tokyo, pp. 599-613.
- RAMASAMY, S.M., VENKATASUBRAMANIAM, V., RIAZ ABDULLAH, S. and BALAJI, S. (1992) The phenomenon of river migration in northern Tamil Nadu-evidence from satellite data, archaeology and Tamil literature. Man and Environ., v.18(10), pp.13-26.
- SINHA, R. (1996) Channel avulsion and floodplain structure in the Gandak Kosi interfan, north Bihar plains, India. Zeitschrift Fur Geomorph., N.F., v.103, pp. 249-268.
- SINHA, R., FRIEND, P. and SWITSUR, V.R. (1996) Radiocarbon dating and sedimentation rates in the Holocene alluvial sediments of the northern Bihar plains. India. Geol. Mag., v.133(1), pp.85-90.
- SINHA R., TANDON, S.K., SANYAL, P., GIBLING, M.R., STUBEN, D., BERNER, Z. and GHAZANFARI, P. (2006) Calcretes from a late Quaternary interfluves in the Ganga Plains, India: Carbonate types and isotopic systems in a mnsoonal setting. Palaeogeo., Palaeoclimat. Palaeoeco., v.242(3-4), pp.214-239.
- SINGH, I.B., ANSARI, A.A., CHANDEL, R.S. and MISRA, A. (1996) Neotectonic control on drainage system in Gangetic plain, Uttar Pradesh. Jour. Geol. Soc. India, v.47, pp.599-609.
- SPRANGERS, J.T.C.M. and BALASUBRAMANIYAM, K. (1978) A phytosociological analysis of the tropical dry evergreen forests of Marakkanam, South Eastern India. Tropical Ecology, v.19(1), pp.170-192.
- SRIVASTAVA, P., JUYAL, N., SINGHVI, A.K., WASSON, R.J. and BATEMAN, M.D. (2001) Luminescence chronology of river adjustment and incision of Quaternary sediments in the alluvial plain of the Sabarmati River, north Gujarat, India. Geomorphology, v.36(3-4), pp.217-229.
- SRIVASTAVA, P., SINGH, I.B., SHARMA, M. and SINGHVI, A.K. (2003) Luminescence chronometry and Late Quaternary geomorphic history of the Ganga Plain, India. Palaeogeo. Palaeoclimat. Palaeoeco., v.197, pp.15-41.
- SUBRAMANIAM, K.S. and MANI, G. (1978) Paleoclimates and laterite formation in Tertiary: A case study in the southern part of the Indian Peninsula. Indian Minerals, v.32, pp.52-54.
- TARDY, Y. (1992) Diversity and terminology of lateritic profiles. In: I.P. Martini and W. Chestworth (Eds.), Weathering, Soils and Palaeosols. Elsevier, Amsterdam, pp.379-405.
- TARDY, Y. and ROQUIN, C. (1991) Geochemistry and evolution of lateritic landscapes. In: I.P. Martini and W. Chestworth (Eds.), Weathering, Soils and Palaeosols. Elsevier, Amsterdam, pp.407-443.
- TILLEY, D.B., MORGAN, C.M. and EGGLETON, R.A. (1994) The evolution of bauxitic pisolith from Weipa, North Queensland. In: 1st Australian Regolith Conference, Broken Hill, Australia, November 1994, Abstracts: Australian Geological Survey Organization (AGSO), Record 1994/56, p.58.
- TILLEY, D.B., MORGAN, C.M. and EGGLETON, R.A. (1995) The bauxitization of a ferruginous-kaolinite mottled horizon; an explanation for the evolution of the Weipa bauxite. In: D. Mayes, Pollard, P.J. (Eds.), 17th International Geochemical Exploration Symposium, Townsville, Australia, May 1995, Abstracts: James Cook University of North Queensland, Economic Geology Research Unit (EGRU), Contribution 54, p.305.
- Palaeontology and Stratigraphy: Basics to Application
Authors
1 Anna University, Chennai, IN
Source
Journal of Geological Society of India (Online archive from Vol 1 to Vol 78), Vol 77, No 5 (2011), Pagination: 494-495Abstract
No Abstract.- Organic Matter Source in the Freshwater Tropical Lakes of Southern India
Authors
1 Department of Geology, Anna University, Chennai 600 025, IN