013340   Gaur A S;Sundaresh;Patankar V (NO, Natn Inst of Oceanography, Dona Paula, Goa-403 004, Email: asgaur@darya.nio.org ) : Ancient shell industry at Bet Dwarka Island. Curr Sci 2005, 89(6), 941-6.

Almost every archaeological site in the Indian subcontinent has the remains of shells. It had been recognized as a major industry during the Indus Valley Civilization, dating back to the mid-Holocene. The most important shell used in the past was Turbinella pyrum (chank) shell, which has been found extensively in inter-tidal zones of Saurashtra and the Gulf of Kachchh. The important artifacts include bangles, beads, seals and inlay work. Bet Dwarka has been the major centre of shell industry in the past. Also, its shore is rich in a variety of shells that were picked up by the fishermen till recently. The article discusses the importance of shell artifacts recovered during the excavation at Bet Dwarka Island and their significance in dating of an archaeological site.

8 illus, 3 tables, 23 ref

013339   Gangoo R K;Koul M N (Dep STOPWORD Geol, Univ of Jammu, Jammu 180 006, Email: ganjoork@rediffmail.com) : Glacial meltwater impounding: Evidence from the late quaternary glaciogenic sediments in the Sangla valley, district Kinnaur, Himachal Pradesh India. J Earth Syst Sci 2005, 114(4), 381-5.

Sangla valley is situated at an altitude of <126> 3500m above mean sea level and lies in the Kinnaur district of Himachal Pradesh. It is fed by river Baspa. a tributary of river Sutlej, that entrenches through the Quaternary glaciogenic deposits before emerging out of the valley and joining the river Sutlej at Karcham. The unstratified to stratified glaciogenic deposits consist of large boulders to fine silt and are classified into four major depositional fades on the basis of sedimentary texture and depositional environment. The facies - basal conglomerates, debris flow, water/sheet flow and laminites - represents the change in the environment of deposition from glaciofluvial to lacustrine and also the extent of the glacier to the valley floor during late Quaternary.

4 illus, 9 ref

013338   Choudhury K;Singh R B;Hakim A;Singh S K (Cent Geophysics Div, Gealogical Surv of India, Kolkata-700 016, Email: kalpan_gsi@yahoo.com) : Geophysical exploration for gold in eastern Mahakoshal Belt. J Geol Soc India 2005, 66(5), 591-8.

Integrated geophysical surveys comprising resistivity and chargeability (both gradient and dipole-dipole), SP, magnetic and borehole mise-a-la-masse methods coupled with geoelectrolysis techniques and geochemical analysis of soil samples led to the delineation of several auriferous sulphide bodies in the eastern Mahakoshal belt. Combined analysis of surface geophysical, borehole geophysical and geoelectrolysis methods are presented in respect of three areas viz. Gurahar Pahar, Tisihwa and Gulaldih. Geophysical interpretations were based on the observed response (parametric survey) over the different exposed rock types in the area. Moderately high chargeability coupled with moderate low resistivity, negative SP, high geo-electrochemical anomaly supported by geochemical soil sample anomaly proved to be indicative of concealed sulphide conductors. Mise-a-la-masse technique delineated the extension of the sulphide body projected on a horizontal plane and its dip direction.

11 illus, 11 ref

013337   Choudhury K (Cent Geophysics Div, Geol Surv of India, Kolkata, Email: kalpan_gsi@yahoo.com) : Estimation of ash content in coal from geophysical logs - a case study from Talcher coal field, Orissa. J Geol Soc India 2005, 66(6), 695-8.

Anomalous response of borehole logging parameters like natural gamma, gamma-gamma and neutron against 104 coal beds encountered in six bore holes in Talcher coalfield, Orissa were studied. Corresponding ash content of the coal beds were also noted from band by band chemical analysis. A relationship thus has been established between the ash content of coal and the corresponding geophysical log response of natural gama, neturon and gamama-gama parameters. A simple geophysical method has been established for determenation of ash content of coal beds from geophys logs in Talcher coal field area. Such methods can also be developed for different coal fields and Gondwana basins of the country paving the way for a much more economic and rapid non core drilling instead of the prevalent expensive core drilling for analysis of ash content of coal samples.

2 illus, 7 ref

013336   Chatterjee H S;Pendkar N;Biyani A K;Dutta D; Shukla M (Spl. Grp. Frontier Basins, ONGC, Dehra Dun-248 195, Email: himschat@rediffmail.com) : Tattapani complex: A new formation at the base of simla group, Himachal Pradesh. J Geol Soc India 2005, 66(5), 561-72.

Variation in tectono -stratigraphic levels of the Sundernagar volcanics/Mandi-Darla volcanics has been soliciting a logical causative - either stratigraphic or tectonic. This communication explains the observed variation to be a reflection of actual stratigraphic separation between two sequences. Based on field evidences and geochemical characteristics, two distinct magmatic episodes are established within the Shali-Simla sequences of Himachal Pradesh. The two magmatic episodes are formally identified as 'Mandi.Complex' and 'Tattapani Complex' (generally referred to as Sundernagar volcanics/Mandi-Darla volcanics) - the former being pre-Shali and the latter post-Shali/pre-Simla. A modified stratigraphy of the area, as per the Code of stratigraphic nomenolature of India, has been proposed.

5 illus, 4 tables, 29 ref

013335   Chatterjee B (Steel STOPWORD Mines Dep Government STOPWORD Orissa STOPWORD Chairman, Orissa Min Corporation, Bhubaneswar) : Orissa-a rich treasure tove of minerals. J Mines Metals Fuels 2005, 53(10), 224-5.

3 ref

013334   Chakrapani G J;Dhingra D;Biswas P (Dep STOPWORD Earth Sci, Indian Inst of Technol Roorkee, Roorkee-247 667) : Chemical weathering by rivers in India. J Indian Wat Resour Soc 2005, 25(2), 16-24.

Weathering by rivers and the transportation of the weathered products is one of the important processes linking continents to oceans. The two fundamental processes of weathering, chemical and physical weathering act complementarity. During chemical weathering processes, atmospheric CO₂ is consumed, which influences the global carbon cycle. In the study authors has tried to put together data of chemical weathering by rivers in India. Silicate weathering is separated from carbonate and other rock types weathering and associated CO₂ consumption is calculated.

2 illus, 3 tables, 24 ref

013333   Chakrabotry P P;Sarkar S (Dep STOPWORD Appl Geol, Indian Sch of Mines, Dhanbad-826 001) : Episodic emergence of offshore shale and its implication: late proterozoic rewa shale, Son valley, Central India. J Geol Soc India 2005, 66(6), 699-712.

Detailed facies analysis in late Proterozoic Rewa Shale reveals three physically distinctive facies that differ in their palcogeography. Between shoreface and outer shelf the facies types are distributed as: (i) shale with thin siltstone/fine sandstone intcrbeds of outer shelf; (ii) shale interbedded with HCS bearing sheet sandstone of inner shelf within storm wave base and (iii) sandstone interbedded with silly shale of distal shoreface paleogeography. High-resolution facies succession analysis revals three different order of depositional cyclicity, the lowest which may be correlated with third-order depositional 'sequence'. Thin (av. 3.5 cm) discrete levels of emergence with their invariable associations and sharp transitions from inner shelf to shoreface facies mark the subaerial discontinuities, which punctuate the apparently monotonous Rewa Shale succession. Far from the coastline on a siliciclastic ramp that lacks shelf-slope break, these features, even though cryptic, can provide important clues for sea level falls in shale dominated successions.

11 illus, 1 table, 57 ref

013332   Bishnoi N R;Tomar A R;Rajender Kumar (Dep STOPWORD Envir Sci STOPWORD Engng, Guru Jambheshwar Univ, Hisar-125 001) : Groundwater and soil quality in surrounding area of distillery of Saharanpur district. Indian J envir Prot 2005, 25(6), 513-17.

Reports the impact of distillery effluent on groundwater and soil quality in the surrounding area of distillery of Saharanpur district of Uttar Pradesh. In case study, the groundwater and soil samples were collected from different sources, namely hand pumps and bore wells in 2 different seasons, that is post-monsoon and winter. These samples were analyzed for parameters, like pH, nitrate, chloride, sulphate, hardness, calcium, magnesium, alkalinity and COD, etc. Majority of the samples did not comply with Indian as well as WHO standards for most of the water quality parameters measured. The soil samples were collected from different agricultural fields at a depth of 1 ft, 2 ft and 3 ft, separately. These samples were analyzed for parameters, like pH, chloride, sulphate, nitrate, calcium, magnesium, etc. Correlation coefficient was calculated to evaluate the relationship among different physico-chemical parameters for groundwater and soil samples. The analytical results indicated that the groundwater quality was found unsatisfactory for drinking purposes.

2 illus, 7 tables, 13 ref

013331   Bhushan S K;Chittora V K (NO, Geol Surv of India, Jaipur-302 004, Email: shihbbanb@yahoo.co.in) : Proterozoic granitoids of Rajasthan. J Geol Soc India 2005, 66(6), 741-63.

Two granitoid bodies each From Palaeo-, Meso- and Neo-protcrazoic periods have been studied for their chemical, petrological and source characteristics. The Proterozoic granitoids are megacrystic as well non-megacrysitc with variable effect by lectonometamorphic events. The Palaeo-proterozoic granitoids are peraluminous, corundum normative with high proportion of biotite in their modal composition. They contain either orthoclase/sanidine or andesine as feldspars and iron rich biotite. The Meso-proterozoic granitoids have high silica with meta- to peralurninous composition. The feldspar chemistry indicates albite/oligoclase composition whereas they exhibit high iron rich biotite and some being lepidomelane in composition. The Neo-proterozoic granitoids are invariably porphyritic having higher silica content (<62>72 wt%). as compared to other granitoids and exhibit strong peraluminous affinity. The feldspar geothermometry indicate 1050°C for Palaeo-, 900-950°C for Meso- and 750°C for Neo-proterozoic granitoids. The Proterozoic granitoids are orogenic, the degree of deformation varies from pristine, non-foliated to gneissic and augen gneissic. mostly 'S' type, indicating a sedimentary source material for their generation. The biotite discriminant diagrams also support 'S' type collisional tectonic setting. The garnet-biotite geothermometery for Palaeo-proterozoic granitoids where these minerals co-exist suggest equilibrium temperature of <126>540°C at 1 or 2kb pressures. There is appreciable replacement in magnetites of Palaeo-proterozoic granitoids by K₂O, SiO₂, Al₂O₃, and negligible in Meso- and Neo-proterozoic rocks. There is gradual increase in SiO₂ and DI from Paleo- to Neo-proterozoic granitoids. The basement complex, after attaining rigidity and cratonisation by the end Archaean igneous activity was rifted periodically during the Proterozoic times. Extensional events led to the formation of mafic dyke swarms, plutonic and volcanic activity and sedimentary platform covers. However, the aborted rifts were further effected by compressive tectonics giving rise to syn and late tectonic deformational signatures to the intrusive phases and their host rocks.

4 illus, 4 tables, 52 ref

013330   Baljeet Singh (Dep STOPWORD Math, Govt Coll, Sector-11, Chandigarh 160 001, Email: baljeet@networkindia.net) : Reflection of P and SV waves from free surface of an elastic solid with generalized thermodiffusion. J Earth Syst Sci 2005, 114(2), 159-68.

Governing equations for generalized thermodiffusion in an elastic solid are solved. There exists three kinds of dilatational waves and a Shear Vertical (SV) wave in a two-dimensional model of the solid. The reflection phenomena of P and SV waves from Tree surface of an elastic solid with thermodiffusion is considered. The boundary conditions are solved to obtain a system of four non-homogeneous equations for reflection coefficients. These reflection coefficients are found to depend upon the angle of incidence of P and SV waves, thermodiffusion parameters and other material constants. The numerical values of modulus of the reflection coefficients are presented graphically for different values of thermodiffusion parameters. The dimensional velocities of various plane waves are also computed for different material constants.

14 tables, 25 ref

013329   Ayolabi E A;Oyelayo F J (Geophysics Program Dep STOPWORD Phys, Univ of Lagos, Lagos, Nigeria, Email: eojelabi@yahoo.com) : Geophysical and hydrochemical assessment of groundwater pollution due to a dumpsite in Lagos state, Nigeria. J Geol Soc India 2005, 66(5), 617-22.

The impact of the buried refuse at the abandoned Achakpo refuse dumpsite in Ajeromi-Ifelodun Local Government area of Lagos State on the groundwater has been carried out using geophysical and hydrochemical methods. The geophysical method involved vertical electrical soundings while the hydrochemical analysis carried out on the samples of groundwater from four hand dug wells in the vicinity of refuse dumpsite and one sample of surface water. Three geoelectric layers were delineated from the interpretation of vertical electrical sounding data and the map of the depth to the top of resistive bed was produced to show the extent of pollution. Supporting evidence was provided by the hydrochemical analysis of samples from groundwater and surface water which show very high value of conductivity, total dissolved solids, total suspended solids. Alkalinity, Total hardness, Ca²⁺, Fe²⁺ and PO₄^3-.

3 illus, 1 table, 14 ref

013328   Arun T;Dhar A;Emperumal K;Pathan B M (NO, Indian Inst of Geomagnetism, Kalamboli (Highway), New Panvel, Navi Mumbai-410 218) : IMF B_Y dependence of the extent of substorm westward electrojet. J Earth Syst Sci 2005, 114(2), 177-84.

Duskward extension of the westward auroral electrojet is investigated for sub-storm intervals on the basis of magnetograms recorded at the Indian Antarctic station, Maitri. The database comprises three years from 1998-2000. Based on an initial study of the magnetograms, an arbitrary local time of 2030 MLT is fixed to define the early manifestation of the substorm westward electrojet. Using this criterion 12 substorms are identified and the possible causes examined. Many of these events are observed to be associated with a moderate to intense ring current. The hourly average of the GSM B_Y-component of the interplanetary magnetic field (IMF) for the hour preceding the substorm onset at Maitri is negative for most of the events. It is suggested that the azimuthal shift of the auroral electrojets in the southern hemisphere resulting from a negative B_Y-component of the IMF influences the extent of the substorm westward electrojet. This finding implies that the IMF may have a role in controlling the longitudinal extent of substorm occurrence.

4 illus, 1 table, 35 ref

012150   Vlladkar S G;Ramesh R;Avasia R K;Pawaskar P B (Dep of Geol, St. Xavier's Coll, Mumbai-400 001, Email: viladkars@yahoo.com) : Extrusive phase of carbonatite-alkalic activity in Amba Dongar complex, Chhota Udaipur, Gujarat. J Geol Soc India 2005, 66(Sept), 273-6.

It is noteworthy that Amba Dongar carbonatite complex has both intrusive and extrusive phase carbonatites. The stratified tuff with components of both carbonatite and nephelinite have been recently traced in western part of Amba Dongar complex. Presents trace and rare earth elements data and C and O isotopes of these tuffs. The C and O isotopes of the least altered tuff falls within the mantle box while the remaining samples plot in the narrow field of 16-20% in oxygen. These values are explained using simple model of water-rock interaction.

^ssc5 illus, 2 tables, 3 ref

012149   Singh K J;Sarate O S;Bhattacharya A P;Goswami S (NO, Birbal Sahni Inst of Palaeobotany, 53, University Road, Lucknow-226 007, Email: kamaljeet31@hotmail.com) : Record of lower gondwana megafloral assemblage from the Nand coalfield, Wardha basin, Nagpur district, Maharashtra. J Geol Soc India 2005, 66(Sept), 293-302.

Rich collection of Lower Gondwana mega-plant fossils have been recorded from the outcrops exposed along the Kharkhara Nala section in Nand coalfield, Nagpur District, Maharashtra, mapped as Lameta Formation. The Lower Gondwana rocks are deposited mainly in Nagpur, Chandrapur and Yeotmal Districts of Maharashtra. Palaeobotanical investigations (megafloral and xylotomical) so far known from Wardha Valley are mostly confined to Barakar and Kamthi Formations. Megafloral assemblage very similar to assemblage of Karharbari Formation has been recovered for the first time from the Lower Gondwana beds exposed in the Nand coalfield. The plant assemblage consists of two species of Gangamopteris, one species each of the genera Buriadia, Noeggerathiopsis and Allatocarpus along with the genus Glossopteris represented by seven species. The conifer genus Buriadia dominates the flora (17.72%) followed by Glossopteris communis (16.46%). The sediments were also investigated for the purpose of palynology but no pollen and spore types could be recovered. An Early Permian age has been assigned on the basis of overall assemblage.

1 illus, 2 tables, 46 ref

012148   Singh A;Singh B D (NO, Birbal Sahni Inst of Palaeobotany, 53 University Road, Lucknow-226 007, Email: alpanas_in@yahoo.com) : Petrology of Panandhro lignite deposit, Gujarat in relation to palaeodepositional condition. J Geol Soc India 2005, 66(Sept), 334-44.

Petrological investigations on Early Eocene lignite from two mine sections of Block-1 in Panandhro Lignite field, under both normal incident (white) and fluorescence (blue light excitation) modes, reveal that deposit is rich in maceral huminite content with sub-ordinate amount of liptinite and low inertinite contents. The maceral composition indicates that sub-bituminous C lignites in both the mine sections are more or less similar with minor differences. Gelification and Tissue Preservation Indices suggest the deposition of lignite in lower delta plain environment in lagoonal conditions.

8 illus, 2 tables, 22 ref

012147   Samant B;Sakurkar C V;Kundal P;Mohabey D M (Postgrad Dep of Geol, Nagpur Univ, Nagpur-440 001, Email: tvandana@sify.com) : Maastrichtian dinoflagellates and palynomorphs from subsurface deccan inter-trap sediments, Khandala-Ashta area, Wardha district, Maharashtra. J Geol Soc India 2005, 66(Sept), 267-72.

164 m thick Deccan volcano sedimentary sequence comprising five flows, separated by four inter-trap beds and overlying the Lameta Formation, has been encountered in borehole KA-1, drilled by the Directorate Geology and Mining (DGM) for the coal exploration in Khandala-Ashta area of Wardha District, Maharashtra. Of these, the inter-trap between the two lowermost flows has yielded a rich spore-pollen assemblage that is dominated by angiosperms and pteridophytes. The presence of palynotaxa such as Azolla cretacea, Ariadnaesporites sp., Gabonisporis vigourouxii, Triporoletes reticulatus and Aquilapollenites bengalensis, suggests a Late Cretaceous (Maastrichtian) age for the sediments. The palynomorphs are associated with a rich dinoflagellate assemblage mostly comprising of Palaeoperidinium and Selenopemphix. The study indicates that the changing climatic and depositional scenario owing to Deccan volcanic eruption has possibly offered the suitable ecological niche for the first appearance of dinoflagellates and gradual domination of the angiosperm flora in the non-marine ecosystem during Late Cretaceous in India.

^ssc15 illus, 36 ref

012146   Ramadass G;Ramaprasada Rao I B;Himabindu D; Veeraiah B (Cent of Explor Geophysics, Osmania Univ, Hyderabad-500 007) : Gravity investigations for structural mapping in the Makthal region, Andhra Pradesh. J Geol Soc India 2005, 66(Sept), 345-53.

Semi-detailed gravity surveys were carried out over an area of approximately 1500 Sq km in and around Makthal (Mahboobnagar district, Andhra Pradesh) in the eastern Dharwar craton to evaluate the structural configuration of the region. Two major, linear deep-seated faults, one running NW-SE and the other N-S, and several other lineaments were identified from the qualitative analysis of the Bouguer gravity data. The zones of intersection of these structural trends which could have acted as potential sites for kimberlite emplacement, were accordingly delineated. The near surface as well as deep crustal configuration in the region was obtained via the inversion of a NE-SW trending gravity profile obtained by digitizing the Bouguer gravity contour map. From the disposition of the crustal layers, a total of five faults were inferred, revealing the structural configuration of the region. These faults were found to correlate well with faults/lineaments inferred from qualitative analysis.

4 illus, 24 ref

012145   Qasim P S Z (Formerly Director, Natn Inst of Oceanography, Dona Paula, Goa) : Tsunami and its aftereffects. SGAT Bull 2005, 6(2), 61-2.

012144   Prasad B N;Prapeep Raj (NO, , 8 floor, BRKR building, Ground Water Department, Hyderabad, Email: gpradeepraj@yahoo.com) : Effect of tsunami on groundwater regime in parts of Andhra Pradesh. J Geol Soc India 2005, 66(Sept), 277-80.

Reports rise of water levels in some of the wells in AP is noted days after the 26 December 2004 earthquake and the accompanied tsunami events. It is found to be due to seepage from sewerage, paddy fields, deliberate filling up of the wells, etc. Classic signature of an earthquake on water levels is missed by all the 1017 piezometers in the state. None of the piezometers show any abnormal change that coincides with the reported changes in water levels of some of the wells. Thus confirming that the earthquake (tsunami) raised false alarms about water table rise. In coastal areas, quality of the groundwater is affected due to direct inundation of the wells and percolation of sea water that inundated the lands and entered far inland through the estuaries.

^ssc3 illus, 1 table, 6 ref

012143   Matin A (Dep of Geol, Asutosh Coll, Kolkata-700 026, Email: amatinindia@yahoo.com) : Tectonics and stratigraphy of the Gurgunta Schist belt of the Dharwar craton, South India. J Geol Soc India 2005, 66(Sept), 303-17.

Early Archaean oval-shaped, high-grade Gurgunta schist belt in the northern part of the eastern Dharwar craton of south India constitutes a part of the intensely deformed migmatized basement of the low-grade volcano-sedimentary sequence of the Dharwar craton. The Gurgunta schist belt consists of two blocks of a migmatised volcano-sedimentary sequence separated by an E-W trending shear zone. Contrary to the earlier interpretations, the regional structure of the belt is not a dome. The earliest episode of deformation (D₁) has produced pervasive planar fabric in metavolcanics and in granitoid rocks after migmatisation of volcano-sedimentary rock in its early history. D₂ has produced major and minor isoclinal folds along with axial planar pervasive gneissic banding while the D₃ has produced major and minor tight to isoclinal folds on foliation. The map pattern is controlled by D₃ deformation. D₄ and D₅ are of mild intensity and less prominent on a regional scale in comparison to earlier deformations. The grade of metamorphism, migmatisation, the structural history and the presence of E-W trending shear zone suggest that the belt is probably older than the low-grade supracrustal belts in the adjoining areas.

16 illus, 2 tables, 22 ref

012142   Mahalik N K (Formerly Professor & Head Geol Dept, Utkal Univ, C/73, HIG Baramunda Housing Board Colony, Bhubaneswar-751 003, Email: mahalik_nk@yahoo.com) : Vulnerability of Indian subcontinent to earthquake and tsunami disasters. SGAT Bull 2005, 6(2), 66-70.

During the first five years of the 21st century (2001-2005) India has witnessed three major earthquake related disaster e.g., the Bhuj earthquake of 26th January 2001 in which 20,000 people died, the Sumatra Tsunami on 26th December 2004, a global event, in which 3 lakhs people died including 10,000 in India and the Muzaffarabad earthquake of the 8th October 2005 in which about 80,000 people died in Kashmir. These are great human tragedies which have shaken the Indians. While the Bhuj earthquake is an intraplate event, the other two relate to plate boundary convergence between Indian and Eurasian plates.

1 illus

012141   Lomax A;Mlchelini A (NO, Anthony Lomax Scientific Software Mouans-Sartoux, France) : Rapid determination of earthquake size for hazard warning. J Geol Soc India 2005, 66(Sept), 365-6.

1 illus, 4 ref

012140   Kanti Roy M;Saha S;Samsuddin Ahmed S;Hasan Mazumder Q (Dep of Geol and Min, Univ of Rajshahi, Rajshahi-6205, Bangladesh, Email: mkr_c@yahoo.com) : Tide, morphology, litho-facies, zonation and evolution of a middle holocene to present estuary-Meghna in South Central Bangladesh. J Geol Soc India 2005, 66(Sept), 354-64.

6 illus, 52 ref

012139   Iyengar R N;Radhakrishna B P (Deparment of Civ Engng, Indian Inst of Sci, Bangalore-560 012, Email: rni@civil.iisc.ernet.in) : Evolution of the western coastline of India and the probable location of Dwaraka of Krsna: geological perspectives. J Geol Soc India 2005, 66(Sept), 285-92.

Description of Dwaraka and its environs, its growth and final destruction as narrated in the ancient classics of Mahabharatha, Hari-vamsa, Skanda Purana and Visnu Parana is presented and it is shown that the Dwaraka built by Krsna could not be the Dwaraka located at the western tip of Saurashtra. Geological evidence shows that the coastline of India is a rifted margin with present day Saurashtra, Kachchh, Pacham, Wagir, Bela and other isolated masses occurring as islands off the rifted western margin; the greater part of Saurashtra formed an island of explosive volcanic activity not directly connected with the Deccan trap of the mainland; the existence of the Cambay basin, a long linear sedimentary basin, more than 500 km long with an average width of 50 km and maximum depth of 7 km linked the basin with the Gulfs of Cambay and Kachchh maintaining marine connection from early Cretaceous to late Pleistocene and early Holocene (5000 years ago); filling up of the basin with enormous amount of alluvium brought by the rivers Saraswati, Luni, Sabarmati and others-are presented as evidences lending support to the view that the present day Dwaraka, isolated and far removed from Mathura could not be the original Dwaraka (Ur-Dwaraka) of Krsna. Ur-Dwaraka was nearer to Mathura and could be reached via .Pushkara (near Ajmer) and Mt. Abu and in all probability was located on the eastern margin of the Cambay basin. The city either was drowned or washed away by the sea around 1400 BC. West coast of Gujarat lies at the junction of the African, Asian and Indian plates and is riddled with many active faults and has been an active seismic zone. Authors make a strong plea for a multidisciplinary study by a group consisting of oceanographers, geologists, geophysicists, sedimentologists, engineers and meteorologists to make an intensive study of the region and elucidate the history of development of this terrain and incidentally solve the problem of the location of Ur-Dwaraka.

^ssc3 illus, 27 ref

012138   Beyarslan M (Dep of Geol, Firat Univ, 23119 Elazig, Email: melahat.beyarslan@gmail.com) : The upper cretaceous ophiolites and magmatic arc rocks in the Eastern Taurus, Turkey. J Geol Soc India 2005, 66(Sept), 323-33.

Eastern Taurus extends from Elbistan to the Iran/Iraq frontier in Eastern Turkey, bounded by the Southeast Thrust Zone to the South. Younger sedimentary and volcanic units discordantly overlie the Palaeozoic-Mesozoic rocks to the north. The Palaeozoic-Mesozoic metamorphic rocks consists of poly-metamorphic gneisses, amphibolites, marbles and schists. The metamorphic units were thrusted onto the ophiolites or the Maden Complex, which is interpreted as continental fragments that have rifted from Gondwana in the Triassic in conjunction with the opening of a southerly Neotethyan ocean basin. Upper Cretaceous magmatic rocks are composed of ophiolites associated with arc-related magmatics. Isolated ophiolite outcrops are generally composed of dunites, pyroxenites, gabbros, dyke swarms and pillow lavas. Unusually, the Guleman ophiolite consists of harzburgitic and dunitic tectonites. The crystallization sequence of gabbros in the Eastern Taurus ophiolites suggests that these ophiolites were formed in a SSZ type setting. Arc-related magmatic rocks include basaltic pillow lavas, and esitic lava flows pyroclastics and granitic intrusions. Field, petrographical and geochemical data also suggest that these magmatic rocks were formed in a supra-subduction zone. The ophiolites are derived from an oceanic crust in the upper plate of a subduction zone. The Upper Cretaceous arc-related magmatic rocks developed on this oceanic lithosphere.

6 illus, 66 ref

012137   Baskaran R;Selvaraj S ;Victor Rajamanickam G (Dep of Geol, Natn Coll, Tiruchirapalli-620 001, Email: baskaranrajagoplan@yahoo.co.in) : A geomorphic appraisal of silica sands of Marakkanam area, Tamil Nadu. J Geol Soc India 2005, 66(Sept), 281-3.

Silica sands of commercial value occur as patches of varied areal extent along the coast near Marakkanam in Tamil Nadu north of Pondichcrry. There are many geomorphic features here. A study of these landforms and the deposits is attempted with a view to bring out the possible relationship between the geomorphic features and the deposits.

^ssc1 illus, 5 ref

012136   Ayolabi E A (Dep of Phys, Univ of Lagos, Lagos, Nigeria, Email: eojelabi@yahoo.com) : Geoelectric evaluation of olushosun landfill site Southwest Nigeria and its implications on groundwater. J Geol Soc India 2005, 66(Sept), 318-22.

Geoelectric resistivity technique of geophysical investigation have been used to evaluate the effect of leachate generated from Olushosun landfill on the groundwater in the area. The result shows that the first aquifer has been greatly polluted by the leachate generated from the decomposed heap of refuse materials at the landfill site. A total depth of up to 73 m has been delineated as polluted area with resistivity ranging from 16 to 361Ωm as compared to resistivity values ranging between 2167-3714Ωm for the unpolluted area. The results of the evaluation of the protective capacity of the overburden material within the unpolluted zone shows that the overburden material has a weak protective capacity and this may have largely been responsible for the high level of pollution observed in this area.

5 illus, 1 table, 10 ref

011215   Wilsone M (NO, , ) : Modeling the Sumatra-Andaman earthquake reveals a complex, nonuniform rupture. J Geol Soc India 2005, 66(4), 499-503.

Data from a global network of seismometers were available within minutes of last December's Sumatra earthquake. Constructing a detailed self-consistent picture of where, when, how fast and how much the sea floor moved has taken months.

2 illus, 6 ref

011214   Watts L J;Beena Kumari;Maass H (Nat Envir Res Coun, Centres for Atmospheric Sci (NCAS), c/o NERC Science Programmes Directorate, Swindon, Wiltshire, SN2 1EU, UK) : Applications of remotely-sensed ocean colour data in the Arabian Sea. Indian J Mar Sci 2005, 34(4), 396-407.

Biological oceanography has been revolutionised by the provision of remotely sensed ocean colour data. These data provide a two-dimensional window into the synoptic state of the ecosystem by providing information on the surface biomass fields. The advances made in the field of biogeochemical studies in the Arabian Sea through the exploitation of such remotely sensed ocean colour data have been considered. It concentrates on the advances made within the framework of the Joint Global Ocean Flux Study (JGOFS), focussing on the period 1994-1996 when the ARABESQUE (UK contribution to JGOFS) oceanographic campaigns took place. It considers the ocean-colour data and algorithms that were available during this period and how they have been used in biogeochemical studies of the area. It then considers advances in the post-JGOFS era and concludes with some recommendations for future studies in the Arabian Sea area. These include: the requirement for further development of regional algorithms for the retrieval of chlorophyll-a concentrations from ocean-colour data, due to the temporal and spatial variation of the bio-optrcal properties observed in the near- and surface waters, within and between the seasons; the further collection of shipboard measurements of P-I parameters, light absorption and pigment data throughout the year and further development of protocols for assigning these parameters to the Arabian Sea area, in the quest to improve primary production estimates on an ocean-basin scale.

3 illus, 3 tables, 70 ref

011213   Wakeel M;Khan K F;Sajid M H A (Dept. of Geol, A M U, Aligarh-202 002, Email: mohdwakeel2001@yahoo.com) : Metamorphic textures in precambrian polymetallic deposits of Sawar-Bajta area, Ajmer district, Rajasthan. J appl Geochem 2005, 7(2), 218-26.

The polymetals consisting mainly of pyrite, pyrrhotite, chalcopyrite, sphalerite and galena, with substantial amount of marcasite, cubanite and oxide minerals, viz., cerussite, cuprite, delafossite and goethite, within the lower marble of the Precambrian Sawar Group in Sawar-Bajta area of Ajmer district, Rajasthan are usually localised in the shear zones and hinge zones of folds. Presence of sulfides along cleavage planes and fractures in silicates, concentration of chalcopyrite and galena in pressure shadows, bent cleavages in galena and transformation of pyrite to pyrrhotite etc., are the result of third phase of deformation.

5 illus, 16 ref

011212   Wahi R;Dubey S;Gwal A K (Space Sci Lab Dep of Phys, Barkatullah Univ, Bhopal-462 024, Email: rashmiwahi@yahoo.com) : Ionospheric total electron content measurement in Malaysian region during high solar activity using GPS receiver. Indian J Radio Space Phys 2005, 34(6), 399-401.

The ionospheric total electron content (TEC) in Malaysian region is examined using Global Positioning System (GPS) receiver. The TEC data of solar maximum (2000-2001) from Marak Parak, Sabah, Malaysia are used. The diurnal, seasonal and annual behaviour of ionospheric total electron content has been studied. Tthe variation of TEC during high solar active period in this region has been studied

3 illus, 4 ref

011211   Usha Madhuri T; (Dep of Envir Stud, Coll of Engng, GITAM, Visakhapatnam-530 045) : A discretised model for ground level concentrations due to stack emissions considering density effects. Indian J envir Prot 2005, 25(2), 105-8.

Man needs only 3 kg/day of water, 1 kg/day of food but requires 16 kg/day of air. In the case of food and water there is an option but man has to breathe the ambient air compulsorily. So air pollution is most dangerous. Air quality modelling plays a pivotal role in the design of an environmental programme. Modelling is needed to predict the pollution levels and to plan to protect the environment from their harmful effects. Air pollution dispersion modelling mainly depends on Gaussian plume equation, which has several limitations, like pollutant density should be the same as that of ambient air. Due to the difference in densities the actual concentration differs from those calculated through Gaussian model.

2 illus, 3 tables, 2 ref

011210   Tejale P M (AMSE Wing, Geol Surv of India (GSI), Bangalore) : Application of aero - geophysical multisensor data in prognosticating mineral deposits - a case study in the adjacent areas of Agucha lead-zinc deposit, Rajasthan. J appl Geochem 2005, 7(2), 134-52.

Airborne geophysical surveys form an unbiased scientific tool for rapid scanning of large tracts of diverse terrains including covered, forested and inaccessible areas. The wealth of geophysical data, acquired and judiciously interpreted, results in a vastly improved understanding of the surface and subsurface geological framework and structures so vital in mineral exploration, in the assessment of groundwater potential, in environmental monitoring and in the elucidation of a host of basic geological processes and problems. Systematic integrated studies involving acquisition, processing and interpretation of aerogeophysical data, followed by ground geological, geochemical and geophysical surveys and drilling, supported by laboratory studies, not only help in unravelling the geology of an area but also help in prognostication of mineral prospects, if any, of a given area. Following the discovery of Rampura-Agucha Lead-Zinc deposit, the AMSE Wing, GSI has launched a programme of multisensor (magnetic, electromagnetic and spectrometric) aerogeophysical survey during 1992-93. Field season covering an area of 6000 sq km in northeastern extension of Rampura-Agucha deposit up to east of Jaipur. The survey was carried out on NW-SE flight lines with 500 m flight line intervals covering six blocks. A major part of the area is covered by soil and occupied by heterogeneous complex of migmatites and gneissic rock belonging to the Sandmata Complex and Mangalwar Complex of the Bhilwara Supergroup. Various qualitative interpretational methods were applied to the IGRF corrected total intensity magnetic maps of the flown area. Ground evaluation of aerogeophysical anomalies in blocks I and II of Agucha-Malpura-Chaksu belt has led to the establishment of the following interpretation on aeromagnetic, spectrometric and electromagnetic signatures. The electromagnetic anomalies of "0" depth mostly fall on water bodies, and since the area is largely covered by soil, the AEM intercepts of considerable depths might possibly be related to bedrock conductor. The area of such AEM intercepts was geochemically sampled and the samples from a few AEM zones have analysed anomalous base metal and gold values. A total of 16 Zones have been identified having the anomalous values of Pb and Zn, besides Cu and Au (Pb ranges from <60> 10 ppm to 0.12% and Zn value show vide variation from 10 ppm to 860 ppm; Cu from <60> 10 ppm to 220 ppm and Au from <60> 0.10 ppm to 0.82 ppm). Such zones are recommended for follow-up re-evaluation through detailed mapping, systematic sampling and ground geophysical work for ascertaining the causative factors of the AEM anomalies. Interpretation of aeromagnetic anomalies has led to the identification of two distinct magnetic domains, viz., (i) Western Domain, characterized by linear zone of strong magnetic anomaly, which corroborates directly to the area of high grade granulite facies rocks of Sandmata Complex and (ii) Eastern Domain, distinguished by weak magnetic anomaly, with intermittent high and broadly defining the rocks of Mangalwar Complex, represented by the Archaean granite-greenstone belt that includes migmatitic gneiss, impure marble, etc. The Delwara lineament is well depicted in magnetic pattern by straight parallel contours from Agucha to Champaneri. Spectrometric data has revealed that the metasedimentary gneiss (paragneiss) is, in general, characterized by low K, U and Th, and while orthogneisses like augen gneiss, hornblende-biotite gneiss and migmatites show higher concentration of these elements. Water bodies and river courses are marked by low concentrations and spectrometric depressions. There is a positive correlation between uranium and total anomalies.

5 illus, 3 tables, 11 ref

011209   Szekielda K H (Geography Dep Hunter Coll Cy, Univ of New York, 695 Park Avenue, New York, NY 10021, U.S.A., Email: szekielda@aol.com) : Use of the first and second chlorophyll absorption bands for marine biogeochemical patch recognition. Indian J Mar Sci 2005, 34(4), 387-95.

Water-leaving spectral signatures were used in the spectral regions where chlorophyll has its first and second absorption bands in order to recognize biogeochemical provinces in the pelagic and coastal ocean. The analysis of spectra collected in eutrophic coastal waters identified a very narrow spectral bandwidth in which the highest correlation between chlorophyll and the first derivative is apparent. A ratio technique using the defined envelope showed that a good relationship exists between the ratio of the reflectance R667/R678 and surface chlorophyll concentrations. The global data set for MODIS 3 used in the study data has a 4.89-km pixel resolution that is mapped on a cylindrical equidistant map projection. The data presented are based on an interpretation of the ratios R443/R551 and R678/R667 that use the spectral region of the two absorption bands of chlorophyll, the fluorescence of chlorophyll at 678 nm and the hinge point at 551 nm. The two selected ratios indicate the response of provinces according to the depth location of absorbing pigments as well as the overall response to integrated concentrations of pigments in the euphotic zone. The results show that biogeochemical provinces can be identified by the ratio technique and upwelling regions, current systems and river discharge can be spectrally separated.

11 illus, 20 ref

011208   Srinivasan V (Geol Surv of India Tripura-Mizoram Div, , B.K. Road, Banamalipur, Agartala-799 001, Email: v_srinivasan_geo@rediffmail.com) : The dauki fault in northeast India: through remote sensing. J Geol Soc India 2005, 66(4), 413-26.

Dauki fault extends roughly E-W along the southern margin of Meghalaya plateau. Using remote sensing techniques followed by critical field checks, the author traced Dauki fault from Dauki towards east upto Leike over a length of 170 km. This fault is a single fault dipping towards south (normal fault). In the footwall block close to the fault trace, the older rocks such as Disang shale (Eocene) and the massive thick-bedded sandstones (Barail Group of Eocene-Oligocene) are exposed. In the hanging wall block close to the fault trace, the alternating sandstone shale sequence ('ribbed sequence', a regional marker) belonging to the upper part of Palaeogene is exposed. In the eastern part of hanging wall block, the regional marker abuts against the folded sedimentaries of Surma basin of Neogene along a tectonic contact, which is also co-folded. The N-S trending axial surfaces of folds in Surma basin bend towards NE to ENE while approaching the trace of Dauki fault, indicating dextral strike slip movement along Dauki fault.This inference is further supported by the outcrop pattern of Haflong thrust in the footwall block with the concavity facing west. This thrust belonging to the 'Belt of Schuppen' abruptly terminates against the younger Dauki fault. In the western part of hanging wall block of Dauki fault, the same marker horizon abuts against the non-folded, undeformed, near horizontal sedimentaries of Sylhet trough of Neogene. It is proposed that the Sylhet sediments were deposited in a pull-apart basin in the releasing bend of Dauki fault during the dextral strike slip movement. Thus the net slip for Dauki fault involves a vertical component and a dextral strike slip component (oblique-slip fault). Sonapur landslide zone is located very close to this fault and the recurring landslide indicates that this fault is still active. The densely populated areas, such as Dacca and Silchar, are located on the loose alluvial sediments not far away from the active Dauki fault.

11 illus, 1 table, 16 ref

011207   Son S H;Campbell J;Dowell M;Yoo S (Dep of Oceanography, Dalhousie Univ, Halifax, NS, B3H 4R2, Canada, Email: seunghyun_son@umit.maine.edu) : Decadal variability in the yellow and east China seas as revealed by satellite ocean color data (1979-2003). Indian J Mar Sci 2005, 34(4), 418-29.

Satellite ocean color data from the Coastal Zone Color Scanner (CZCS) in 1979 to 1984 and the Sea viewing Wide Field-of-view Sensor (SeaWiFS) in 1998 to 2003 are examined to determine whether there have been changes in chlorophyll concentration and suspended sediment as indicated by changes in satellite-derived optical properties during the past two decades in the Yellow and East China Seas (YECS). Water-leaving radiance measurements at 443 and 555 nm [the CZCS band is centered at 550 nm, but this is ionsidence comparable to the SeaWiFS 555-nm band] and have been compared possible reasons for the changes observed. The shallow coastal areas of the YECS exhibited high water-leaving radiance in the 555-nm have been discussed and (L_W555) during two time periods, indicating that these waters are sediment-dominated Case-2 waters. Between the CZCS era and the SeaWiFS era, L_W443 increased in these areas by 17%-61%, and LW555 increased by 67-108%. In the deeper waters, L_W443 decreased by 25%-31%, which would indicate an increase in absorbing materials such as chlorophyll and colored dissolved organic matter (CDOM). Between the CZCS and SeaWiFS eras, the average chlorophyll concentration (based on Case-1 algorithms) increased by 15-60% in these offshore deep waters. Periodical in situ measurements from 61 stations in the western coast of Korea from 1978 and 2002 were compared with the trends found in satellite data. The results show that there were increasing trends in temperature and zooplankton biomass, and decreasing trends in salinity and Secchi depth. The satellite data surrounding these stations showed an increase in L_W555 (49 %), a decrease in the L_W443 (-12 %), and an increase in chlorophyll (46 %). From the results, it is inferred that there have been environmental changes in the Yellow Sea during the last two decades from 1979 to 2003.

6 illus, 1 table, 22 ref

011206   Solanki H U;Pradhan Y;Dwivedi R M;Nayak S; Gulati D K;Somvamshi V S (Mar and Wat Resour Grp Remote Sens and Image Processing Area, Space applications Cent (ISRO), Ahmedabad-380 015, Email: himmatsinh@sac.isro.org) : Application of QuikSCAT SeaWinds data to improve remotely sensed potential fishing zones (PFZs) forecast methodology: Preliminary validation results. Indian J Mar Sci 2005, 34(4), 441-8.

Chlorophyll concentration and sea surface temperature (SST) images derived from IRS P4-OCM and NOAA- AVHRR have been used to delineate the oceanographic features exhibiting different oceanic processes. QuikSCAT-Sea Winds derived wind vectors were used to understand, establish, quantify and to demonstrate the variability of wind induced watermass flow as well as their impacts on features/oceanographic process. Oceanographic features like eddies, rings and fronts were found shifted as per movement and direction of the wind. The movement of water mass due to wind provides insight of environmental factors relevant to dispersal of fishery resources. An algorithm was developed to compute water mass transport and feature shift. Based on these studies an approach for incorporating QuikSCAT-SeaWinds data to improve PFZs forecast methodology has been developed. The improved PFZs forecast methodology was validated through near real time fishing operations. About 82-85% success rate was reported during validation experiments carried out during 2004. The improved methodology would prolong the validity of PFZs forecast.

6 illus, 1 table, 11 ref

011205   Singh R P;Sangita Dey;Rajan G K (Dep of Geol, Banaras Hindu Univ, Varanasi-221005, Email: rpsingh0251@rediffmail.com ) : Artificial recharge of groundwater in the upper catchement area of Kumari river basin. Bull pure appl Sci-Sect F 2004, 23(1-2), 47-57.

Artificial recharge of groundwater involves augment of the movement of surface water into groundwater formations by some methods of construction. Artificial groundwater recharge is becoming increasingly necessary as growing population require more water and as more stores is needed to save water in times of surplus for use in time of shortage. The investigation of artificial recharge of groundwater in the upper catchments area of the Kumari river basin has been carried out in an area by latitude 22°-55'-23°-l5' N and longitude 86°-08' -86°-38' situated in the western part of the Purulia district, West Bengal. The Kumari river is the main tributary of the Kasai river which is finally drains its water into the Bay of Bengal. Rain and snow being the primary renewable source of water and rain water harvesting viewed in wider prospective forms the primary source of water for artificial groundwater recharge. The wider prospective of rain water harvesting Includes water from perennial or ephemeral streams regulated with dams, storm runoff including that of urban areas, ponds and lakes. Infact any source of surplus water directly originated from snow or rain. The other sources of recharge water may originate from aqueducts or other water conveyance facilities, irrigations areas, drinking water treatment plants and sewage water treatment plants. Artificial recharge of groundwater is expected to play an increasing role in reuse of wastewater because movement of water through soils and aquifers provides a means of geo-purification of water through the process known as Soil -Aquifer-Treatment (SAT).

4 photo, 3 illus, 13 ref

011204   Saxena V K;Singh V S;Mondal N C;Maurya A K (NO, Natn Geophys Res Inst, Hyderabad-500 007, Email: vks_9020010@yahoo.co.in) : Quality of groundwater from Neil Island, Andaman and Nicobar, India. J appl Geochem 2005, 7(2), 201-6.

A systematic hydro-geochemical study was carried out to assess the quality of groundwater in Neil Island, Andaman and Nicobar. Twenty two groundwater samples were collected in October/November 2003 from open wells, bore wells and hand pumps. Chemical analysis was carried out for major cations, anions and trace elements. The study indicates that: These waters are nearly neutral to mildly alkaline (pH: 7.2-7.9), and their total dissolved solids vary from 374-1270 mg 1 and can be classified into Na-Ca-Cl-HCO₃ and mixed types. Of the samples 86% show hardness (CaCO₃) <62> 250 mg/lit and are considered to be hard - water, and about 30% of the area is covered with limestone and its probable interaction with groundwater may be the cause for this hardness. Furthermore, the Ca vs. TDS, HCO₃ vs. TDS and SO₄ vs. EC plots show a fairly good correlation. It is observed that at present the influence of seawater intrusion is almost negligible, but if excessive withdrawal of groundwater is continued, the possibility for brackishness will be more. It is suggested that this groundwater is suitable for agricultural purpose. The data show that major cations, anions and trace elements are within permissible limit of potable water. Sodium and Cl are the most dominantions, and a good correlation exists between Na -Σcations and Cl -Σanions.

3 illus, 2 tables, 7 ref

011203   Sathyendranath S;Stuart V;Platt T;Bouman H; Ulloa O;Maass H (Oceanography Dep, Dallhousie Univ, Halifax, Nova Scotia, B3H 4J1 Canada) : Remote sensing of ocean colour: Towards algorithms for retrieval of pigment composition. Indian J Mar Sci 2005, 34(4), 333-40.

Ocean colour varies as an inverse function of the absorption coefficient. In Case 1 waters, phytoplankton are known to be the principal agents responsible for variations in the total absorption coefficient. The concentration and composition of pigments present have a strong influence on phytoplankton absorption spectra. Empirical (regression) algorithms exist to recover the wavelength-specific absorption coefficient of phytoplankton from the concentration of the main pigment, chlorophyll-a. However, to explain the residuals about such regressions remains a major challenge. Authors has analysed a set of over 1,600 absorption spectra of phytoplankton collected from various oceanographic provinces. In parallel, authors examined the corresponding pigment complexes, as revealed by High Performance Liquid Chromatography (HPLC).Authors have uncovered broad trends in the shapes of the absorption spectra and in the pigment complexes, consequent upon changes in the pigment biomass, with clear implications for the remote sensing of ocean colour.

7 illus, 3 tables, 26 ref

011202   Santosh Kumar;Thepfuvilie Pieru;Vikoleno Rino (Dep of Geol, Kumaun Univ, Nainital-263 002, Email: skyadavan@yahoo.com ) : Evaluation of granitoid-series and magmatic oxidation of neoproterozoic south khasi granitoids and their microgranularenclaves, Meghalaya: constraints from magnetic susceptibility and biotite composition. J appl Geochem 2005, 7(2), 175-94.

High-K, calc-alkaline, I-type (metaluminous), Neoproterozoic South Khasi granitoids (SKG) (690±19 Ma) of West Khasi Hill district in Meghalaya plateau intrude the Gneissic Complex and Shillong Group of metasediments. The microgranular enclaves (ME) are ubiquitous in the SKG pluton and more frequent in the center. The SKG and their ME have been evaluated in terms of magnetic susceptibility (MS) and biotite compositions. More than 90% of measurements of both have values greater than 3.0 x 10^-3 SI units, suggesting their affinity with magnetite series (oxidized type) granitoids. The eastern part of the SKG pluton shows ilmenite series (χ<3.0 x 10^-3 SI units) affinity due to felsic magma intrusion in the Shillong Group. Molar Al₂O₃/CaO + Na₂O+K₂O (metaluminous, I-type) and bulk Fe₂ O₃/FeO ratios of SKG and ME are largely consistent with their magnetite series character. The biotites in SKG and ME are compositionally similar belonging to Mg and Fe²⁺ biotites and have affinity with primary biotites crystallized in association with amphiboles, which probably equilibrated under similar physical conditions (P, T, fO₂, f_H2O)- MgO, FeO^t and Al₂O₃ contents of biotite from SKG and ME suggest Mg ≤ Fe substitution and their evolution in a subduction-related tectonic setting. Based on observed MS values and biotite compositions of ME and SKG, it is suggested that most of the SKG and their ME belong to magnetite series (oxidized type) granitoids, in which biotite evolved and buffered between FMQ and NNO in an open system that most likely attained during mafic (enclave) and felsic (SKG) magma mixing and mingling processes.

6 illus, 3 tables, 41 ref

011201   Rathod V (NO, Natn Inst of Oceanography, Dona Paula, Goa-403 004, Email: rathod@darya.nio.org) : Zooplankton studies with special reference to krill Euphausia superba Dana from fishing area 58 of Indian Ocean sector in Southern Ocean. Curr Sci 2005, 89(4), 681-6.

Distribution, abundance and species composition of zooplankton collected during the First Indian Antarctic Krill Expedition were studied. Zooplankton biomass values ranged from 9.79 to 303.62 ml 100 m^-3 (x = 142.14 ± 77.02). High standing stock values were recorded in the study area, where copepods, chaetognaths, euphausiids and salps were dominant taxa. Copepods and chaetognaths formed the major constituents of zooplankton community and comprised more than 70% of zooplankton catch. Swarms of kirll and salps were observed during the study period (austral summer), which were the prime cause for high standing stock of zooplankton. The prevailing physico-chemical parameters with rich food supply were important factors influencing the geographical distribution of different zooplankton groups. The study revealed that the present investigation site falls under potential krill fishing ground.

4 illus, 1 table, 33 ref

011200   Rashid S A;Sharma K K (Dep of Geol, AMU, Aligarh-202 002, Email: rashidamu@hotmail.com) : Paleoproterozoic granitoids as basement rocks for the himalayan sedimentary rock sequences - a comparative geochemical study. J appl Geochem 2005, 7(2), 153-65.

Occurrence of Proterozoic granites and their associated mafics all along the 2000 km Lesser Himalayan belt is significant in terms of their geological setting and geochemical characters. One such granitic body and its associated mafic rocks have been studied here mainly to understand their petrogenesis and tectonic significance. Recent geochronological studies and the present results suggest that the granites that occur along the Lesser Himalayan belt are geochemically similar and are older than the associated basalts. These investigations further suggest that these Proterozoic granites form the basement for the younger volcano-sedimentary rocks.

7 illus, 1 table, 31 ref

011199   Rao B V;Thong G T (Dep of Geol, Nagaland Univ, Kohima-797 002) : Groundwater investigations in the Khondalitic terrain of Vemulapudi area, Visakhapatnam district, Andhra Pradesh. Bull pure appl Sci-Sect F 2004, 23(1-2), 25-9.

Resistivity surveys were carried out around Vemulapudi village. Visakhapatnam District, Andhra Pradesh in khondalitic terrain of the Eastern Ghats Bell of South India. The khondalites are medium to coarse grained and occur as fractured and massive varieties. These khondalites are capped by insitu lateritic soil. The khondalite outcrops form parallel ridges that arc cut across by streams such as the Varaha and Surpa. The inter-stream areas are characterised by plains. The plains and foothills are covered by lateritic soil. The water table occurs at depths between 3.1 and 3.9 m below the surface. Dug-wells are common. Vertical Electrical Sounding was conducted using the Schlumberger method with a maximum electrode spacing (AB/2) of 100 m. The terrain exhibits a two layered model. The unsaturated soil cover exhibits a resistivity range from 2.60 to 31.00 ohm m. whereas the resistivity in the saturated horizon of khondalites ranges from 6.40 to 46.50 ohm m. The thickness of the weathered saturated horizon varies between 6.50 and 25.00 m. Below this horizon is a deep fractured zone of the khondalites.

1 illus, 1 table, 6 ref

011198   Ramasamy V;Murugesan S;Mullainathan S (Dep of Phys, Annamalai Univ, Annamalai Nagar-608 002) : Characterisation of minerals and relative distribution of quartz in Cauvery river sediments from Tamil Nadu India-A FTIR study. Bull pure appl Sci-Sect F 2004, 23(1-2), 1-7.

Mineralogical composition of Cauvery river sediments starting from Poombhuhar to Hoggenakal. as determined by FTIR Analysis, includes quartz, feldspar, kaolinite as major and nacrite, illite, montmorillonite. chlorite, gibbsite and carbonates as minor. The quality of the quartz mineral is substantiated by calculating the crystallinity index. The relative distribution of quartz among the various sites are determined using extinction coefficient of the characteristic peak at 778 cm^-1. The quartz present in the samples from the site no. 11 is relatively well crystalline form than others.

3 illus, 1 table, 12 ref

011197   Rajawat A S;Gupta M;Pradhan Y;Thomaskutty A V;Nayak S (Mar and Wat Resour Grp Space Applics Cent, ISRO, Ahmedabad-380 015, Email: asrajawat@sac.isro.gov.in) : Coastal processes along the Indian coast - case studies based on synergistic use of IRS-P4 OCM and IRS-1C/1D data. Indian J Mar Sci 2005, 34(4), 459-72.

The Sequential Suspended Sediment Concentration (SSC) maps were generated using IRS-P4 OCM (Ocean Color Monitor) data for selected tide dominated, wave dominated and deltaic coasts around the Indian subcontinent. Patterns of SSC were studied to understand the sediment dynamics, circulation patterns, fronts and consequent impact on coastal processes. Hitherto, unknown sediment plumes extending for large distance into deep offshore areas could be identified from the major deltaic regions. The high temporal capability of OCM data was extremely useful to understand sediment dynamics in tide-dominated regions of the Gulf of Khambhat, the Gulf of Kachchh and the Hoogli estuary. SSC maps in conjunction with corresponding tide and bathymetry data could be sequenced as per flooding and ebb cycles. Development, formation, shifting nature of shoals and sediment curls during a tide cycle could be studied. It is observed that during the North-East (NE) monsoon suspended sediment influx of the Ganga-Brahmaputra system influences the coastal processes along the continental margins of the Orissa and the Northern Andhra Pradesh along east coast of India. The occurrence of cyclone aids in entrapment of fluvial discharge into the coastal waters, leading to a reduced offshore influx into deeper regions of the Bay of Bengal and high sedimentation near to the coast. Seasonal changes along wave-dominated west coast showed net sediment transport from north to south in the pre-monsoon season and south to north in post-monsoon season. Significant onshore- offshore transport along west coast was also observed. The impact of the regional sediment dynamics on the site-specific local coastal environment was studied by integrating observations derived from OCM and IRS-1C/1D data. The paper concludes the utility of Ocean Color Monitor and IRS-1C/1D data in studying various coastal processes and regional sediment dynamics.

11 illus, 1 table, 13 ref

011196   Nayak B R;Mohapatra B K (NO, Natn Metall Lab, Jamshedpur-831 007, Email: bk_mohapatra@yahoo.com) : Morpho-chemistry of hematite in manganese-rich formation of Gangpur group Orissa. J Geol Soc India 2005, 66(4), 486-90.

The Precambrian manganese-rich formation (Goriajhar Formation) Gangpur Group contains appreciable Fe, as reflected from the occurrence of hematite in different paragenesis. The first generation of hematite (Hm,) exhibits dissimilar micromorphology, contains Mn in solid solution (MnO: 1 to <60>4%) and may be termed as manganoan-hematite. The different morphological types (Hm₁,) recorded are: hexagonal plate, twinned idiomorph, subhedral inclusion within quartz and braunite, blebs forming zone within spessartine garnet, crystal dusted with oriented intergrown ilmenite, haphazard platelets within Mn-aegirine, oriented grains forming alternate bands and fused grains forming large porphyroblast. The hematite formed due to martitisation is of second generation (Hm₂) and the one that occurs as vein fillings, often traversing the other two types, is of third generation (Hm₃). Both Hm₂ and Hm₃ are devoid of Mn content. The first generation hematite is of primary type, syngenetic with manganese minerals and developed at different stages of metamorphism. The hematite of other two generations is of hypogene origin, Hm₂ being formed due to low-temperature oxidation, while Hm₃ during solution and reprecipitation at meteoric condition.

2 illus, 1 table, 10 ref

011195   Nair R J (NO, Cent Mar Fish Res Inst, Kochi-18) : Silverbelly fishery of palk bay and gulf of mannar with special reference to Leiognathus jonesi (James, 1967). Indian J Fish 2005, 52(2), 189-95.

Silverbellies constitute an important group of demersal fishery resource along Tamilnadu coast. They are exploited by trawl and a variety of artisanal gears like shore seines, boat seines and gill nets. The southeast region contributed nearly 85% of the silverbelly landings of India and Tamilnadu's share was 70%. Out of 20 species of silverbellies known from India, 15 species are found in varying proportions from the Palk Bay and Gulf of Mannar. Good fishery for silverbellies at Rameswaram was recorded from February to September and October to March at Pamban, during the years 1996-2000. The length-weight relationship of L. jonesi was W = 0.000076197 L²³⁸. The growth parameters L_∞ and K (annual) were 161 mm and 0.71 respectively. The MSY was estimated at 209.7 t.

6 illus, 2 tables, 16 ref

011194   Nageswara Rao P V;Swaroop P C;Ranga Rao V (Dep of Geol, Nagarjuna Univ, Nagarjunanagar-522 510, Email: pusapati_vnr@yahoo.com) : Significance of grain size data in interpreting the depositional environment of sandstone formations of Pangidi area, West Godavari district, Andhra Pradesh. Bull pure appl Sci-Sect F 2004, 23(1-2), 31-40.

Thirty samples representing from Tirupati. Infratrappean and Rajahmundry Sandstones of Pangidi area were selected for textural analysis. These sandstones are coarse to medium grained, moderately well to well sorted, nearly symmetrical to very positively skewed and mesokurtic to leptokurtic nature. The univariant grain size parameters indicates that those sandstones resembles the modern fluvial sands. Different bivariant discriminant plots, linear discriminant function, paleo-geomorphology and fossil assemblage reported in the literature inferred that the Tirupati, Infratrappean and Rajahmundry sandstones were the products of the sediments transported by the Godavari river channels and these sediments arc reworked by existing velocity of currents under shallow marine conditions and deposited one after another at the suitable channel basin conditions.

3 illus, 2 tables, 23 ref