015423   Jokhan Ram (KDM Institute of Petroleum Exploration, Oil and Natural Gas Corporation Limited Kaulagarh Road, Dehradun-248 195) : Applications of geochemistry in petroleum exploration- current and future trends. J appl Geochem 2007, 9(2), 272.

015422   Jinadasa S U P (Oceanography Div, National Aquatic Resources and Development Agency (NARA), Crow Island, Colombo 15, Sri Lanka) : Comparison of resistivity imager and self potential applications in ground water investigation in hard crystalline terrain of Sri Lanka. J Geophys 2007, 28(1-2), 33-43.

A geological and geophysical study was carried out to investigate groundwater accumulations in the hard rock terrain in Monaragala, Sri Lanka. It is important to identify the subsurface structures in the area for studying groundwater bearing formations. In the past, traditional methods were widely used for identification of regional geological structures. Information from geological methods alone does not provide reliable clues to groundwater accumulations. These methods appear to be suitable for detection of subsurface structures onlv. Therefore, it is important to carry out different geophysical survey methods to confirm these results. Timbiriya area in Monaragala district Sri Lanka was selected to conduct this study Geological nap and aerial photo interpretation show the subsurface structures in this area. The well-defined lineaments run along the Mandappan Ova and its tributaries in Timbiriya area could be clearly identified. Small-scale linear structures could be identified in Malgastalawa and Nakkala areas. During this study resistivity imagei system and self-potential methods were carried out together to get better comparison of both methods. Site selection was done with the assistance of magnetic survey, which was conducted in the previous year in Monaragala area. These locations were identified as geologically weak zones, favourable for groundwater accumulation. Possible subsurface structures could be identified by resistivity method as well as the self-potential methods. But magnetic data interpretations do not always corroborate with the resistivit) and self-potential interpretations. Comparison of resistivity and self potential always gives better result than resistivity imager survey alone.

21 illus, 16 ref

015421   Jeelani G;Shah A Q (Geology and Geophysics Dep, Kashmir Univ, Srinagar-190 006, Email: jkhanday@yahoo.co.in) : Hydrogeochemistry of Dal lake of Kashmir valley. J appl Geochem 2007, 9(1), 120-34.

Water samples collected from the four basins of Dal Lake of Kashmir Valley are characterized by differential natural and anthropogenic influences. Like other Himalayan lakes, Dal Lake is alkaline in nature, dominated by Ca, Mg and HCO₃ ions. The scatter diagrams [Ca +Mg / TZ+ Ca + Mg / HCO₃, Ca + Mg / HCO₃ + SO₄, Na + K / TZ+: Ca + Mg / Na + Kl and the geological map of the catchment area suggest predominance of carbonate weathering with some contributions from the silicates and Karewa deposits. Ca-HCO, (70%) and Ca-Mg-HCO₃ (<60>30%) waters reflect the meteoric character of the lake water, the common source of the ionic species and the role of water rock interaction in the catchment area. Low pH and high TDS, EC and NO₃ in Gagribal basin and in some patches of Nagin basin reflect input of sewage from surrounding population, houseboats, hotels etc. In general, higher ionic concentration in winter and lower in summer in the lake water is largely governed by the contribution of snow melt waters from the catchment area during summer. In the Gagribal basin and some patches of Nagin basin the enhanced concentration of TDS. Cl and NO₃ in summer may be attributed to the tourist pressure and/or agricultural practices in the floating gardens.

5 illus, 4 table, 20 ref

015420   Hanumanthu R C;Vijaya Kumari P;Padmasree P (Geol Dep, S.V. Univ, Tirupati-517 502) : Geochemistry and petrogenesis of granitoids in peddavuru schist belt, Andhra Pradesh, India. Indian Mineralogist 2007, 41(1), 59-75.

The granitoids in Peddavuru schist belt include the banded gneiss and granites. Compositionally the banded gneiss is tonalite-trondhjemite and the granites are tonalite to granite through granodjorite. The stratigraphic position of the banded gneiss is not juxtaposed with the schist belt litho-units nor seen as intrusive into the schist belt. But the granjtes show clear cut intrusive relationship with the schist belt and holdjng the enclaves of metabasalts, the component of the schjst belt. The structural features indicate the possibility of the sialic basement for the schjst belt sequence whose modjfied remnants are probably represented by the banded gneiss. The tongues and apophyses of granites in the schist belt rocks, crude compositional layering, planar arrangement of mafic/felsic schilleren and arrangement of porphyrites of K-feldspar are some of the field evidences to show that the granites are magmatic; thjs is further corroborated by hypidiomorphjc granular texture. The perthjtic and myrmekitic intergrowth are resulted by exsolution. The Alumina Saturation Index (ASI) show that the granitoids are of metalumjnous character. They exhibit calc-alkaline geochemical features and show crust and mantle origin. These granatoids can be classified as I-type granites.

11 illus, 3 tables, 34 ref

015419   Ganesh a A V;Krishnaiah C;Jayappa K S (DOS in Geol, Manasagangotri, Univ of Mysore, Mysore-570 006, Email: ganmysore@hotmail.com) : Mineralogical studies of laterites around Mangalore, Karnataka, India. Indian Mineralogist 2007, 41(1), 76-83.

A preliminary study on the mineralogical aspects of laterite profile in the Mangalore region was carried out employing XRD and FTIR techniques, The laterite profile is the resultant of the residual physico-chemical weathering of Peninsular gneisses, XRD analyses of laterite samples collected from 10 different areas shows that gibbsite, kaolinite and haematite are the major minerals, The lithomarge clay is made up of mainly kaolinite and forms the lower most constituent of laterite profile, Quartz is a stable residual phase and decreases with depth.

4 illus, 1 table, 14 ref

015418   Dwivedi S L;Pathak V (Chem Dep, Faculty of Sci, Mahatma Gandhi Chitrakoot Gramodaya Vishwavidyalay, Chitrakoot-485 331) : Hydro-chemical characteristics of Mandakini river at Chitrakoot. Indian J envir Prot 2007, 12(11), 1006-10.

Water quality of river Mandakini was assessed from Sati Anusuya to Karwi. Altogether 4 samples were collected from each sampling station and 5 sampling stations were selected for analysis. The quality analysis was made through the estimation of temperature, turbidity, DO, pH, EC, TDS, sodium, potassium, calcium, magnesium, carbonate, bicarbonate, chloride, Sulphate, nitrate and phoshpate. The water quality of river Mandakini get degraded with respect to some of the analyzed parameters as it proceeds towards Karwi. Calcium and magnesium are dominating cations (accounting for about 65 to 75 % of the total cations) and bicarbonate and carbonate anions (accounting for about 75 to 89 % of total anions) were found dominating in river water.

9 tables, 10 ref

015417   Dinesh A C;Nambiar A R;Unnikrishnan E; Jayaprakash C;Rao C V (NO, , Geological Survey of India, Marine Wing, Mangalore-575 001) : Mn and Mg, and Mn/Mg ratio in detrital ilmenite - an indicator of provenance?. J appl Geochem 2007, 9(1), 112-9.

Elemental geochemistry, particularly Mn and Mg contents, and the Mn/Mg ratio of detrital ilmenites, is widely used as a provenance indicator. The Mn and Mg contents in ilmenites from kimberlites and related rocks are well established, but ilmenites from other rock types show inconsistent and conflicting data. Available data on Mn and Mg contents, and Mn/Mg ratio of ilmenties from different rock types (other than kimberlites and related rocks), as well as from coastal placer deposits of India, and also from major crystalline rocks in the hinterland of these deposits are synthesised to examine the applicability of this ratio in identifying the source rock(s). Ilmenites from very different rock types like basalt, charnockite, biotite gneiss and syenite have similar Mn/Mg ratio of <60>l. The ilmenites from most coastal sands have also identical Mn/Mg ratios. Hence the data are insufficient to establish criteria for identification of source rocks of detrital ilmenites solely on the basis of Mn/Mg ratio. If Mn/Mg ratio unique to ilmenite from individual rocks can be established by large number of grain specific analyses, then only this ratio can be used as a provenance indicator.

3 tables, 31 ref

015416   Dhembare A J (Zool Dep, P.V.P. Coll, Pravaranagar-413 713) : Diversity of zooplankton from dnyaneshwarsagar water, Rahuri, Maharashtra. J expl Zool 2007, 10(1), 175-9.

In the study spread during a year (July-2004 to June 2005) an attempt is made to enumerate the density and distribution of zooplankton during three seasons in Dnyaneshwarsagar water. Over all its density was higher in winter and lower in rainy. It showed seasonal variations. In general the zooplankton constitute the tendency is in order such as rotifers (40.2%) <62> copepods (28.27%) <62> cladoceran (18.92%) <62> protozoa (12.54%). The diversity and density of zooplankton depends upon various factors. The rotifers dominated among the zooplankton organisms.

1 illus, 2 tables, 27 ref

015415   Dewakar ;Banerjie V;Niranjan N (Regional Geoscience Laboratories, ONGC, Sivasagar, Assam, Email: dewakaripe@yahoo.com) : Petroleum systems in Upper Assam basin. J appl Geochem 2007, 9(2), 193-9.

Source rock evaluation, oil -oil correlation and oil - source correlation studies in the North Shelf of Upper Assam Basin have been carried out to upgrade the knowledge on petroleum systems in the Basin.'The sedimentary cover in.the basin consists dominantly of Tertiary sequences resting unconformably over-the granitic basement. Most oil occurs in reservoirs of Mio - Pliocene Tipam and Oligocen? Barail formations. Oil also occurs in middle to late Eocene Kopili and Sylhet formations and Paleocene Tura Formation:Middle to Late Eocene Kopili and Oligocene Barail formations are the source rocks. Five distinct petroleum systems have been described. First system comprises of Barail Coal Shale as source rock, Tipam sand 1 to Tipam sand 3 sands as reservoirs and Girujan Clay as cap rock in Geleki and Lakwaoil fields. The oil is of relatively low API gravity (Avg 24) with moderate maturity (Avg 0.59%VRc). Second petroleum system contains high API gravity oils (Avg. 3 1.3) with moderate maturity (Avg 0.64%VRo) in Tipam Sand 4 to Tipam Sand 6 sands with Lower Clay Member as cap rock. These oils have also been sourced by Barail Coal Shale. Third system consists of very high API gravity oils (Avg 50) with moderate maturity (Avg 0.6%VRc) occurring inLBSS to LBS6 sands which were also sourced by Barail Coal Shale and Barail Coal is acting as cap rock. Fourth system comprises of Barail Coal Shale / Kopili as source rock and LBS1 to LBS4 sands as reservoirs which contain moderately mature (Avg 0.57%VRc) oils with average API of 30. Cap rock is not well defined in this system. Thin streaks of coal / shale present locally are acting as cap rock in different pools/fields. Fifth system is in Sylhet/Tura formation in which isolated pools have been found in Lakwa and Panidihing areas of ONGC. Major commercial discovery has been made in Oil India Ltd area in this system, from which about 1MMT oil is being produced per annum. Oil in this system is believed to have been generated by Tura formation and Sylhet limestone is acting as cap rock.

2 illus, 13 ref

015414   Dash S K;Banerjee S;Dinesh Kumar;Boopathi D; Pawan Kumar;Behera ;Chishti A;Mahadevappa P;Kalpande P P;Das Gupta D J (NO, Geological Survey of India, Jaipur, Email: djdasgupta2003@yahoo.com) : National geochemical mapping-a preview on the spatial products in Rajasthan. J appl Geochem 2007, 9(2), 247-55.

Geological Survey of India has initiated a National Geochemical Mapping programme under the acronym NGCM in 2001. This mapping programme is designed to obtain a baseline geochemical dataof the entire 3.2 million sq km area of the country through stream sediment sampling at 1 km grid, supplemented with collection of topsoil and soil from 'C' horizon at 5'(or ca 8 km) interval along with flowing water. Also flood plain samples and humus are to be collected from selected places. The data thus generated will benefit the exploration activity as well as provide baseline information to the national agriculture and environmental planning programme. The methodology of sampling is based on IGCP-340 and its predecessor IGCP-259 with a strong influence of the Chinese model of survey. Although a substantial coverage has been achieved at National level in India in these five years the data products are yet to be showcased. This communication intends to highlight the National venture of Geological Survey of India with focus on the achievements in Rajasthan.

5 illus, 2 tables, 5 ref

015413   Bhushan S K (Gelogical Survey of India, , Hyderbad, Email: shibbanb@yahoo.co.in) : Malani volcanism. J appl Geochem 2007, 9(2), 276-7.

015412   Bhandari A;Prasad I V S V;Dwivedi P (NO, , K.D.M.I.P.E., Oil and Natural Gas Corporation Ltd. (ONGC), Dehradun-248 195, Email: bhandarianil88@yahoo.co.in) : Stratigraphic distribution of hydrocarbons in the sedimentary basins of India. J appl Geochem 2007, 9(1), 48-73.

In India, twenty-six sedimentary basins, covering an area of 3.14 million sq km both onland and offshore, occur in varied geological settings. Dedicated efforts by the petroleum explorationists, for more than a century, have proved the huge hydrocarbon potential of India. Geo-tectonically, these basins are broadly grouped into (a) Platform or Cratonic basins (intracratonic and pericratonic) and (b) Rapid subsiding basins. Commercial quantities of hydrocarbons are established in seven basins, (i) Assam Shelf, (ii) Cambay, (iii) Mumbai Offshore, (iv) Cauvery, (v) Krishna-Godavari. (vi) Tripura-Cachar and (vii) West Rajasthan. Hydrocarbons discovered in these basins are entrapped in reservoirs, which range in age from Pre-Cambrian (fractured Basement) and Triassic to Pliocene. Total resources of these basins are estimated around 28 billion tonnes of oil and oil equivalent gas (OEG). The initial in place of hydrocarbons in these basins are of the order of 7.89 billion tonnes of O+OEG and ultimate reserves of 2.94 billion tonnes have been established. An analysis of the stratigraphic distribution of the discovered hydrocarbons globally indicates that about 52 % of the oil is in the Mesozoic rocks followed by 27% in the Cenozoic, 20% in the Paleozoic and balance in Pre-Paleozoic rocks. In contrast to this, in the Indian basins, however, over 97% of the discovered hydrocarbon comes from the Cenozoic, about 2% from the Mesozoic and remaining from the Paleozoic. This fact, if considered to be an indicator of exploration index, suggests basins, bome out of the early successes coming from Cenozoic basins. However, with over ten Indian basins having a Mesozoic depositional history and many of them in the marginal marine to marine realm, these along with the geologically older basins like the Vindhyan and Gondwana basins as well as Himalayan thrust Fold Belts and Proterozoic basins merit more attention from the explorationists to augment hydrocarbon reserves in Indian sedimentary basins apart from the Deep Waters. Strategies have to be evolved to model the petroleum systems for exploration in such basins.

16 illus, 8 tables, 20 ref

015411   Bhandari A (KDM Institute of Petroleum Exploration, Oil and Natural Gas Corporation Limited Kaulagarh Road, Dehradun-248 195, Email: bhandarianil88@yahoo.co.in) : Depositional environment, distribution of source rock and geochemistry of oils and gases, Krishna-Godavari basin. J appl Geochem 2007, 9(2), 271-278.

015410   Baruah P K;Meghali G;Bhuyan S;Baruah R M (Applied Geology Dep, Dibrugarh Univ, Assam, India) : Sedimentology and petroleum prospect of eocene-oligocene Disang and Barail groups of the Patkai hills of Assam-Arakan fold belt, NE India. J appl Geochem 2007, 9(1), 74-90.

The Assam-Arakan fold belt in northeast India runs from the Patkai hills at its easternmost Naga Hills and Manipur in the southeast to Mizoram in the south.The Patkai Hills in the belt presents a complete Tertiary stratigaphic succession from Eocene Disang to Phocene Group. The outcropping Lower Tertiary Disang and Barail groups occur as thrust slices in which the rocks of the Disang Group are more argillaceous whereas they become more arenaceous upward in the stratigraphic horizons of the Barail Group. The succession of the upper part of the Disang Group comprises of the alternation of sand and shale in which the sand: shale ratio varies from 1:7 to 1:0.26. Graded turbidites, centimetre-scale (3 to 6cm) low-angle crosses (2 to 4"), micro-scale wavy ripples and parallel lamination are the sedimentary structures recorded in the rocks of the Disang Group. The sand dominated fades of the Disang succession may be representative of proximal part whereas the shale-dominated part represents deep-water deposits (Mutti and Ricci Lucchi. 1978; Mutti. 1981). The Barail Group is dominantly arenaceous with minor intervening shales in which the sand:shale ratio varies from 1 :0.07 to 1:1.2. The sandstones are fine to coarse grained, light grey in colour. well indurated and cross-bedded. The sedimentary structures and lithological assemblages suggest near shore high-energy environments for the Barail Group. The sandstones of the Disang and Barail groups are "Lithic-arenite" and "Lithic Graywacke" types in which the matrix contentvaries between 8.5 and 26%. The quartz overgrowth, authigenic mica and secondary chert are mainly responsible for the occlusion of intergranular sandstone porosity. Sericitization of feldspar is present in the Barail Group. Although minor, the feldspar dissolution produces secondary porosity in the sandstones. Clay-rich sandstones show poor intergranular porosity Silica, clay and iron oxides are the cement types present in the sandstones. Besides floating grains. the framework elements show point, long, concavo-convex and sutured gram contacts. Kaolinite is the dominant clay mineral in the sandstone. The TOC contents of the Disang and Barail groups indicate fair to very good organic matter richness. The sediments of the Disang and Barail groups contain Type-Ill organic matter, which is usually viewed as gas-prone. The porosity values suggest poor reservoir characteristics for the sandstones of Disang Group (2-8%) and good to very good resenoir characteristics for the sandstones of Barail Group (2-30%). The oil saturation value ranges from trace to 1.34% with an average of 0.33% for the sandstones of the Disang Group and that for the Barail Group of rocks ranges from trace to 2.20%. The water saturation for the sandstones of the Disang and Barail groups ranges from 26.60% to 5 1.28% and 6.83% to 85.71% respectively. The values indicate that the sandstones of the Barail Group possess good reservoir characteristics.

6 illus, 4 tables, 38 ref

015409   Balaram V (NO, National Geophysical Research Insititute, Hyderbad-500 007, Email: balaram1951@yahoo.co.in) : Exploration for platinum group elements (PGE) in peninsular India-status, problems and scope. J appl Geochem 2007, 9(2), 278.

015408   Arun Kumar K;Achyuthan H (Geology Dep, Anna Univ, Chennai-600 025, Email: karun1531@yahoo.co.in) : Heavy metal accumulation in certain marine animals along the east coast of Chennai, Tamil Nadu, India. J envir Biol 2007, 28(3), 637-43.

Heavy metals disposed through anthropogenic activities find their way into the oceans and seas through the rivers or through direct fall out from factory effluents. These heavy metals resuspend back into the water column along with the sediments and are known to affect the marine animals. Marine animals like fish, prawn, crab and mussel were collected along the East Coast (off Pulicat lake to Chennai Harbour) to evaluate trace metal concentrations in various tissues. The above specimens accumulated heavy metals such as Zn, Pb, Cu, Co, Cr, Ni and Cd. Fish, prawn, crab and mussel revealed higher concentration of heavy metals such as Zn, Pb, Cr, Co, Cu and Ni and Cd in low levels. The results revealed that the heavy metal concentrations in the marine animals are below the threshold levels associated with the toxicological effects and the regulatory limits. The bioconcentration factors revealed that the animals have accumulated heavy metals along the food chain ratherthan from the water column and sediment.

5 illus, 1 table, 29 ref

015407   Arora T;Ahmed S;Revil A (IFCGR, NGRI, Hyderabad-500 007) : Rigourous geostastical analysis of the self potential signals to delineate the contaminant plumes. J Geophys 2007, 28(1-2), 45-50.

Accurate mapping of the redox potential and the electrical conductivity of groundwater is important in flelineating the shape of a contaminant plume. Organic matter-rich contaminant plumes, e.g., associated with leakages from municipal landfills, are the source of electrical potential variations at the earth's surface giving rise to Self-Potential (SP) anomalies. The SP data acquired in a plume contanimated region in Entressen. France from September, 2001 to March 2002 has been processed by geostatistical techniques to accurately identify the polluted zone. The plume can be regarded as a natural geobattery, in which the source current results from degradation reactions of the organic matter by the growth of micro-organisms. The self-potential depends on groundwater flow (electrokinetic contribution) and redox conditions (electroredox). The electrical source associated with this electroredox process adds to the contributions associated with (1) the electrokinetic conversion of ground water flow and (2) membrane or diffusion potentials associated with concentration gradients of the ionic species present in the pore water. Once the electrokinetic contribution is removed, a correlation between in situ redox potentials measured in piezometers and the electrical potential measured at the ground surface using non-polarisable electrodes exists. A geobattery model can explain how organic matter-rich contaminant plumes behave as geobatteries and are the source of a natural electrical field. This field can be recorded at the ground surface and used to map the redox potential of the leachate plume using the self-potential method as an efficient non-intrusive technique. Using the variation of the piezometric head in the aquifer, the electrokinetic contribution is removed from the SP signal. A good correlation is obtained between the residual SP data and the redox potential values. This relationship is used to draw a redox potential map over the overall contaminated site.A case study from Entressan Landfill in France is presented here.

8 illus, 15 ref

015406   Anto Francis K (Geol Dep, M.A. Coll of Engng, Kothamangalam Coll, P.O. Ernakulam Dist, Kerala-686 666, Email: kfanto@rediffmail.com) : Vestiges of ultrahigh pressure (UHP) metamorphism from kambam valley, Tamil Nadu: evidence for deep crustal burial and tectonic unroofing in Madurai block, south India. Indian Mineralogist 2007, 41(1), 30-58.

Detailed petrographic and thermobarometric studies of mafic granulites, charnockites and metapelites give evidence for an ultrahigh pressure (UHP) metamorphism predating a high-ultrahigh temperature granulite metamorphism. Thermobarometric estimates, using core composition of porphyroblastic garnet, orthopyroxene and plagioclase included in the porphyroblastic garnet from mafic granulite give ultrahigh pressures of 9.l-9.8kbar. Rapid decompression of the ultrahigh pressure assemblage is documented by the development of symplectitic orthopyroxene and plagioclase around garnet. Estimates using the symplectitic phases and the rim composition of the porphyroblastic garnet give pressures of 6.6-7 .lkb, suggesting drop in pressure by about 2.5kb during decompression. Decompression textures like development of orthopyroxene at the expense of garnet in charnockite, formation of cordierite on garnet, development of cordierite-spinel symplectite after garnet-sillimantie and growth of orthopyroxene-magnetite on cordierite are observed in metapelites. The mineral assemblages in chamockite and metapelite give medium pressures (5-7kb) and high to ultrahigh temperatures (800-950°C). The core-rim pressures estimates show dro b about 2kb, further substantiating the decompression event. The ultrahigh pressures indicate that the interlayered sequence was buried to at least 30km depth where they recrystallised to granulite grade. Such deeply formed granulites usually reside at depth for considerable span of time.

6 illus, 4 tables, 55 ref

015405   Anand S P;Rajaram M (AMG India Pvt.Ltd, , Delhi) : Agromagnetic method in regional mapping and exploration of mineral and groundwater exploration : an overview. J Geophys 2007, 28(1-2), 17-23.

Describes case histories on the successful application of aeromagnetic method for the regional geological mapping over a part of the Dharwar craton and Southern Granulite Terrain, and for delineating Uranium deposits in Singhbhum craton.

2 illus, 27 ref

014145   Tayade S T;Rakesh Kumar;Deshmukh S (NO, National Environmental Engineering Research Institute (NEERI), 8-B, Dr. Annie Besant Road, Near Worli Flyover, Worli, Mumbai-400 018, Email: neeri@bom1.vsnl.net.in) : Performance of small scale systems for domestic wastewater treatment using wetland systems. Bionano Front 2007, 1(1), 24-31.

Three sub-surface flow wetland cells were assessed for their performances for treatment of domestic wastewater on pilot scale. Cells With Typha latifoli and Scirpus validus were compared with the control cell without any plant species. Presents the results of Typha latifolia and Scirpus validus which has not been studies well in tropical climate like in India. In this study, wetland cells received pre-treated wastewater through septic tank. Efficiencies of the cells were assessed for reductions in chemical oxygen demand (COD), ammonium (NH₄-N), nitrate (N0₃-N), nitrite (N0₂-N), total coliforms (TC) and faecal coliforms (FC). The study was carried out at an average hydraulic retention time of 1.80 days. Better performance for the vegetated cells B (Typha latifolia) and C (Scirpus validus) were obtained as compared to the control cell A. Nutrient were observed to be highest removal in vegetated wetland cells Band C as compared to control cell A. The COD removal rate was 34.5, 83.4 and 72.3% for control cell and cells with Typha latifolia and Scirpus validus respectively. TC and FC removal ranged from 46 to 88%, least removal as compared to control cell.

4 illus, 3 tables, 47 ref

014144   Rani S;Singh S J (Mathematics Dep, Jambheshwar Univ, Hisar-125 001, Email: s_b_rani@redffimail.com) : Quasti static deformation due to two dimensioal seismic sources embedded in an elastic half space in welded contact with a porelastic half space. J Earth Syst Sci 2007, 116(2), 99-111.

The Biot linearized theory of fluid saturated porous materials is used to study the plane strain deformation of a two-phase medium consisting of a homogeneous, isotropic, poroelastic half-space in welded contact with a homogeneous, isotropic, perfectly elastic half-space caused by a two-dimensional source in the elastic half-space. The integral expressions for the displacements and stresses in the two half-spaces in welded contact are obtained from the corresponding expressions for an unbounded elastic medium by applying suitable boundary conditions at the interface. The case of a long dip-slip fault is discussed in detail. The integrals for this source are solved analytically for two limiting cases: (i) undrained conditions in the high frequency limit, and (ii) steady state drained conditions as the frequency approaches zero. It has been verified that the solution for the drained case (<119>w <142>-> 0) coincides with the known elastic solution. The drained and undrained displacements and stresses are compared graphically. Diffusion of the pore pressure with time is also studied.

10 illus, 1 table, 20 ref

014143   Ingole B (Biological Oceanography Div, National Institute of Oceanography, Dona Paula, Goa-403 004, Email: baban@darya.nio.org) : Biodiversity of benthic polychaetes from the coastal waters of Paradip, Bay of Bengal. Bionano Front 2007, 1(1), 32-45.

Polychaete communities of the subtidal waters off Paradip (Lat. 20'05' - 20'20' N and Long. 86'35' - 86'60'E) in the Bay of Bengal were studied' on a seasonal basis. Composition, distribution and diversity of macrobenthic assemblage were investigated by deploying a van Veen grab at 17 stations in 10 to 30-m water depths. The subtidal sediment off Paradip coast was predominantly of fine-to-very fine particles and rich in organic carbon (mean=1.59±0.85%, n=17). Macrobenthic community was rich and diverse comprising of annelid worms and small crustaceans. The composition of macrobenthos differed considerably between the seasons. The abundance (density and biomass) of macrofauna was higher at shallower depth (near-shore stations) mainly due to the dominance of polychaetes. A total of 79-macrofaunal invertebrate species belonging to 13 phyla and 45 families were identified. The fauna was mainly composed of polychaetes (41.3%), crustaceans (20.6%), molluscans (15.4%), echiurid worms (7.2%) and echinoderms (2.7%). The contribution of polychaetes in soft sediment macrofauna was almost 50%. Out of 20 tops ranked polychaete species, Nephthys sp., was the important in terms of "Biological Index of Dominance" (BID), whereas Cossura longocirrata was the most abundant. Both these species had wider distributional range and contributed over 27% to the polychaete density. Diversity of macrofauna was higher at offshore (deeper) stations whereas, density was higher at near-shore (shallower) stations. The lower polychaete diversity at nearshore was due to the persistent physical disturbance (dredging activity). Therefore, this study demands for precautionary measures before allowing further alteration in the sedimentary conditions of the area.

8 illus, 5 tables, 66 ref

014142   Hussain S A (NO, Wildlife Institute of India, Chandrabani, Dehra Dun (Uttarakhand)) : Integrated management of wetlands, a case study on asan conservation reserve, Uttarakhand, India. Indian For 2007, 133(10), 1305-11.

Integrated wetland management is a process through which managers can develop a vision, agree on shared values and make informed decisions and act together to manage the natural resources of a river basin. The primary condition for achieving integrated wetland management is the willingness of sectoral stakeholders to work together. All stakeholders need to understand the endowment and value of water resources and learn on how to manage human needs without jeopardizing wetland functions. The present case study aims to highlight the interests and positions of the various stakeholders on the water management in the Asan Barrage and the initiatives taken by the Uttarakhand Forest Department in developing a water storage reservoir the Asan Barrage in to a 'Conservation Reserve' through consultative process and effective participation of stakeholders.

6 ref

014141   Dutta D;Ambwani K;Prasad M (Centre of Advanced Study in Geology, University of Lucknow, Lucknow-226 007) : Occurrence of upper-cretaceous fossil palm wood, Palmoxylon bhisiensis sp. nov. from the lameta formation of Bhisi village, Maharashtra, India. J appl Biosci 2007, 33(1), 8-13.

Present fossil palm wood, Palmoxylon bhisiensis sp. nov., belonging to the family Arecaceae, described here constitutes the first record from the Lameta Fonnation (Upper Cretaceous), exposed at Bhisi village of Nand-Dongargaon inland basin, Nagpur District, Maharashtra State. The specimen is well preserved to reveals all the anatomical characters for its identification. The fossil wood is characterized by the presence of lacunar ground tissue-divisible into distinct outer and inner parts, presence, of leaf trace bundles, tabular parenchyma and stegmata (Phytoliths) constibJte important anatomical features. Absence of fibrous and diminutive bundles is noted. The present fossil palm wood with highly lacunar ground tissue signifies an aquatic environment in the area.

2 illus, 49 ref

014140   Bragadeeswaran S;Rajasegar M;Srinivasan M; Kanaga Rajan U (Centre of Advanced Study in Marine Biology, Annamalai University, Parangipettai-608 502, Email: pragathi_rediffmail.com) : Sediment texture and nutrients of Arasalar estury, Karaikkal, south-east coast of India. J envir Biol 2007, 28(2), 237-40.

Sediment samples were collected for texture, composition and nutrient such as organic carbon, total nitrogen and total phosphorus for a period of two years from three stations in Arasalar estuary. The sediment temperature, pH and nutrients were higher during summer season and lower during monsoon season. At station 1, sediment texture was loamy sand during summer and premonsoon season. At station 2, clay type soil was recorded. Whereas, at station 3, clay was observed in summer and premonsoon and then it shifted to sandy loam type soil during monsoon. Sediment nutrients were lower than that of values of various ecosystem of India.

1 illus, 1 table, 26 ref

014139   Bishnoi M;Arora S (Environmental Science and Engineering Dep, Guru Jambheswhar University of Science and Technology, Hisar-125 001, Email: mukulbishnoi@yahoo.co.in) : Potable groundwater quality in some villages of Haryana, India: focus on fluoride. J envir Biol 2007, 28(2), 291-4.

Fluoride concentration in ground water was determined in ten villages of Rohtak district of Haryana state (India). The fluoride concentration in the underground water of these villages varied from 0.034-2.09 mg/l. Various other water quality parameters, viz., pH, electrical conductivity, total dissolved salts, total hardness, total alkalinity sodium, potassium, calcium, magnesium, carbonate, bicarbonate, chloride and sulfate were also measured. A systematic calculation of correlation coefficients among different physicochemical parameters indicated considerable variations among the analyzed samples with respect to their chemical composition. Majority of the samples do not comply with Indian as well as WHO standards for most of the water quality parameters measured. Overall water quality was found unsatisfactory for drinking purposes. Fluoride content was higher than permissible limit in 50% samples.

2 illus, 5 tables, 17 ref

013097   Venkatesh B;Jose M K (NO, National Institute of Hydrology, Hanuman Nagar, Belgaum-590 001, Email: bvenki30@yahoo.com) : Identification of homogeneous rainfall regimes in parts of western ghats region of Karnataka. J Earth Syst Sci 2007, 116(4), 321-9.

In view of the ongoing environmental and ecological changes in the Western Ghats, it is important to understand the environmental parameters pertaining to the sustenance of the region. Rainfall is one such parameter governing the hydrological processes crucial to agriculture planning, afforestation and eco-system management. Therefore, it is essential to understand rainfall distribution and its variation in relevance to such activities. The study is an attempt to gain in-depth understanding in this direction. The study area comprises of one coastal district and its adjoining areas in Karnataka State. Mean annual rainfall data of 93 rain gauge stations distributed over the study area for a period of 10-50 years are used for the study. In order to assess the variation of rainfall across the ghats, several bands were constructed parallel to the latitudes to facilitate the analysis. The statistical analyses conducted included cluster analysis and analysis of variance. The study revealed that there exist three distinct zones of rainfall regimes in the study area, namely, Coastal zone, Transition zone and Malanad zone. It is observed that, the maximum rainfall occurs on the windward side ahead of the geographical peak. Further, mean monthly rainfall distribution over the zones has been depicted to enable agricultural planning in the study area.

9 illus, 2 tables, 13 ref

013096   Sunita Rani;Singh S J (Mathematics Dep, Jambheshwar Univ, Hisar-125 001, Email: s_b_rani@redffimail.com) : Quasti static deformation due to two dimensioal seismic sources embedded in an elastic half space in welded contact with a poroelastic half space. J Earth Syst Sci 2007, 116(2), 99-111.

The Biot linearized theory of fluid saturated porous materials is used to study the plane strain deformation of a two-phase medium consisting of a homogeneous, isotropic, poroelastic half-space in welded contact with a homogeneous, isotropic, perfectly elastic half-space caused by a two-dimensional source in the elastic half-space. The integral expressions for the displacements and stresses in the two half-spaces in welded contact are obtained from the corresponding expressions for an unbounded elastic medium by applying suitable boundary conditions at the interface. The case of a long dip-slip fault is discussed in detail. The integrals for this source are solved analytically for two limiting cases: (i) undrained conditions in the high frequency limit, and (ii) steady state drained conditions as the frequency approaches zero. It has been verified that the solution for the drained case (ωw → <62>0) coincides with the known elastic solution. The drained and undrained displacements and stresses are compared graphically. Diffusion of the pore pressure with time is also studied.

10 illus, 1 table, 20 ref

013095   Sulthana M (P.G. Research and Zoology Dep, Presidency College, Chennai-600 05) : Coliform contamination of drinking water in north Chennai city, Tamil Nadu, India. J Aquatic Biol 2007, 22(1), 247-50.

Due to shortage of rainfall the water has not been supplied properly by the pipeline system to the north Chennai city. Instead the Government has made arrangements to supply drinking water by tankers to the city. Drinking water in twelve water supply areas (pipe line and water tanker) in the Chennai city has been examined over an annual cycle for faecal coliform contamination as measured in terms of MPN. It was recorded to range from 5 to 342.00/100 ml(tap water) and 2-38.00/100 ml (tanker water) in different areas. There is marked correlation of MPN was noted with seasons and source of water supply. It was positively correlated with the pH of water and number of patients of waterborne diseases. Defects in water supply lines and unhygienic condition of the water tankers are attributed as factors for contamination of water.

3 tables, 8 ref

013094   Sivakumar S D;Gururajan B;Thirukumaran K; Karunanithi S;Umashankar R;Babu C (Tamil Nadu Rice Research Institute, Tamil Nadu Agricultural Univ, Aduthurai-612 101) : Impact of nutrient sources on yield and nutrient uptake of inter cropped clusterbean under rainfed cotton. J Ecobiol 2007, 20(3), 281-5.

Field experiments were conducted during rabi seasons of 2001-02 and 2002-03 at Regional Research Station, Tamil Nadu Agricultural University, Aruppukottai, to study the impact of cluster bean under different sources of nutrient supply. Among the nutrient sources, application of vermicompost at 50 per cent N substitution registered higher yield attributes number of pods/plant (14.3 & 12.7), number of pods/plant (60.0 & 50.2 ), 100 pod weight (284 & 275 g), green pod yield ( 3997 & 3692 kgha^-1) and N uptake (49.9 & 45.0 kgha^-1), P uptake (7.76 & 5.97 kgha¹) and K uptake (21.3 &17.13 kgha^-1) in 2002-03 & 2002-03 .respectively. This was followed by bio-digested weed compost at 50 per cent N substitution and composted coirpith at 50 per cent N substitution. Significant reduction in growth attributes, yield attributes and yield were observed under 100 per cent N P applied as inorganic fertilizers to base crop, while it was on par with composted coirpith and bio-digested weed compost both, applied at 100 per cent N substitution.

1 table, 6 ref

013093   Singh O P;Hatwar H R;Onkari Prasad (NO, Indian Meteorological Dep, Mausam Bhavan, Lodhi Road, New Delhi-110 003, Email: opsingh@imdmail.gov.in) : Surface and upper air meteorological features during onset phase of 2003 monsoon. J Earth Syst Sci 2007, 116(4), 305-10.

Second campaign of the Arabian Sea Monsoon Experiment (ARMEX-II) was conducted in two phases viz., March-April and May-June 2003. In the work, the buoy and ocean research vessel data collected during the second phase of ARMEX-II have been analysed to bring out the characteristic features of monsoon onset. The results have shown that the thermodynamical features such as build up of lower tropospheric instability and increased height of zero degree isotherm occurred about a week before the monsoon onset over Kerala and adjoining southeast Arabian Sea. There was a sharp fall in the temperature difference between 850 and 500 hPa, and the height of zero degree isotherm about 2-3 days before the monsoon onset. The flux of sensible heat was positive (sea to air) over south Arabian Sea during the onset phase. Over the Bay of Bengal higher negative (air to sea) values of sensible flux prevailed before the monsoon onset which became less negative with the advance of monsoon over that region. The pre-onset period was characterized by large sea surface temperature (SST) gradient over the Arabian Sea with rapid decrease towards north of the warm pool region. The buoy observations have shown that SST remained close to 30.5°C in the warm pool region during the pre-onset period in 2003 but only 2-3 degrees away (north of this region) SSTs were as low as 28.5-29°C. An interesting aspect of sea level pressure (SLP) variability over the Indian seas during the onset phase of summer monsoon 2003 was undoubtedly, the highest SLP in the warm pool region in spite of very high SSTs.

5 illus, 15 ref

013092   Sindhu B;Suresh I;Unnikrishnan A S;Bhatkar N V;Neetu S;Michael G S (NO, National Institute of Oceanography, Dona Paula-403 004, Email: smole@nio.org) : Improved bathymetric datasets for the shallow water regions in the Indian Ocean. J Earth Syst Sci 2007, 116(3), 261-74.

Ocean modellers use bathymetric datasets like ETOPO5 and ETOPO2 to represent the ocean bottom topography. The former dataset is based on digitization of depth contours greater than 200m, and the latter is based on satellite altimetry. Hence, they are not always reliable in shallow regions. An improved shelf bathymetry for the Indian Ocean region (20° E to 112°E and 38°S to 32°N) is derived by digitizing the depth contours and sounding depths less than 200m from the hydrographic charts published by the National Hydrographic Office, India. The digitized data are then gridded and used to modify the existing ETOPO5 and ETOPO2 datasets for depths less than 200 m. In combining the digitized data with the original ETOPO dataset, it apply an appropriate blending technique near the 200m contour to ensure smooth merging of the datasets. Using the modified ETOPO5, it demonstrates that the original ETOPO5 is indeed inaccurate in depths of less than 200m and has features that are not actually present on the ocean bottom. Though the present version of ETOPO2 (ETOPO2v2) is a better bathymetry compared to its earlier versions, there are still differences between the ETOPO2v2 and the modified ETOPO2. Assesses the improvements of these bathymetric grids with the performance of existing models of tidal circulation and tsunami propagation.

11 illus, 1 table, 31 ref

013091   Sharma M D (Mathematics Dep, Kurukshetra University, Kurukshetra-136 119, Email: mohan_here@rediffmail.com) : Wave propagation in a general anisotropic poroelastic medium: Biot's theories and homogenisation theory. J Earth Syst Sci 2007, 116(4), 357-67.

Anisotropic wave propagation is studied in a fluid-saturated porous medium, using two different approaches. One is the dynamic approach of Biot's theories. The other approach known as homogenisation theory, is based on the averaging process to derive macroscopic equations from the microscopic equations of motion. The medium considered is a general anisotropic poroelastic (APE) solid with a viscous fluid saturating its pores of anisotropic permeability. The wave propagation phenomenon in a saturated porous medium is explained through two relations. One defines modified Christoffel equations for the propagation of plane harmonic waves in the medium. The other defines a matrix to relate the relative displacement of fluid particles to the displacement of solid particles. The modified Christoffel equations are solved further to get a quartic equation whose roots represent complex velocities of the four attenuating quasi-waves in the medium. These complex velocities define the phase velocities of propagation and quality factors for attenuation of all the quasi-waves propagating along a given phase direction in three-dimensional space. The derivations in the mathematical models from different theories are compared in order to work out the equivalence between them. The variations of phase velocities and attenuation factors with the direction of phase propagation are computed, for a realistic numerical model. Differences between the velocities and attenuations of quasi-waves from the two approaches are exhibited numerically.

3 illus, 35 ref

013090   Sharma K K;Sawhney N;Sarbjeet Kour (Zoology Dep, Jammu Univ, Jammu-180 006) : Some limnological ivestigations in Ban Ganga stream, Katra, Jammu & Kashmir state. J Aquatic Biol 2007, 22(1), 105-9.

Ban Ganga stream is a shallow snow fed stream at an altitude ranging from 1750mts. to 2150 mts. above M.S.L. in Trikuta hills of Jammu division of J&K state. This shallow snow fed stream in addition to having religious significance is the only source of water to Katra town. Thus, this water body is under constant anthropogenic influence. Keeping in view its immense importance, an attempt has been made to analyse the limnological status of the stream. For the assessment of water quality, various physico-chemical parameters (Temperature, Speed, Depth, pH, DO, FCO₂, CO₃3, HCO₃, Cl, Ca++ and Mg++) were studied at the pre-established stations which reflected all the three different zones of a stream system. The data collected highlights the need to keep a check on anthropogenic interference to maintain the health and integrity of the stream.

1 illus, 1 table, 30 ref

013089   Sener M (Geology Dep, Nigde Univ, 51200, Nigde, Turkey, Email: msener@nigde.edu.tr) : Depositional conditions of the coal-bearing Hirka formation beneath late Miocene explosive volcanic products in NW central Anatolia, Turkey. J Earth Syst Sci 2007, 116(2), 125-35.

This work focuses on the relationship between the coal deposition and explosive volcanism of the Miocene basin, NW central Anatolia, Turkey. The coal-bearing Hirka Formation was deposited over the Galatian Andesitic Complex and/or massive lagoonal environments during the Miocene. The investigated lignite is a high ash (from 32 to 58%) and sulphur (from 1.43 to 3.03%) lignite which is petrographically characterised by a high humunite content. The mineral matter of the studied lignite samples is made up of mainly clay minerals (illite-smectite and kaolinite), plagioclase and quartz in Bolu coal field, clay minerals (illite-smectite, smectite and illite), quartz, calcite, plagioclase and gypsum in Seben coal field, quartz, K-feldspar, plagioclase and clay minerals (kaolinite and illite) in Kibriscik, and dolomite, quartz, clinoptilolite, opal CT and gypsum in Camlidere coal field. The differences in these four types of lignite with specific mineralogical patterns may be due to the explosive volcanic events and depositional conditions which changed from one coal field to the others. There is a zonation from SW to SE in the studied area for zeolites such as Opal CT+smectite-clinoptilolite-analcime-K-feldspar. Carbonate minerals are commonly calcite in Seben and Kibnscik coal fields. In Bolu. coal samples are devoid of calcite and dolomite. These analyses show that there is an increase in the amount of Mg and a decrease in the amount of Na from the northwestern part to the southern part in the study area.

6 illus, 4 tables, 21 ref

013088   Salve B S;Hiware C J (Zoology Dep, Milind College, Parli Vaijnath-431 515) : Water quality of Wanparakalpa reservoir, Nagpur, near Parli Vaijnath, dist, Beed, Marathwada region. J Aquatic Biol 2007, 22(1), 113-17.

Deals with the study of physico-chemical nature of water from Wanparkalpa reservoir. Seasonal variation in atmospheric and water temperature, pH, chlorinity, alkalinity, total hardness, dissolved oxygen, free carbon dioxide, total solids, biochemical oxygen demand and chemical oxygen demand were studied during January to December 2000. Water samples were collected from selected three sites (S₁, S₂, & S₃). Monthly analysis during study period states that, throughout the study period water was alkaline in nature, temperature showed negative co-relation with dissolved oxygen and many other related things are discussed at length in the text.

25 ref

013087   Sajani S;Naseema Beegum S;Krishna Moorthy K (NO, Vikram Sarabhai Space Centre, Trivandrum-695 022, Email: sajanirajendran@yahoo.com) : Role of low frequency intraseasonal oscillations in the anomalous Indian summer rainfall of 2002. J Earth Syst Sci 2007, 116(2), 149-57.

Authors analyze the dynamical features and responsible factors of the low-frequency intraseasonal lime Scales which influenced the nature of onset, intensity and duration of active/break phases and withdrawal of the monsoon during the anomalous Indian summer monsoon of 2002 - the most severe drought recorded in recent times. During that season, persistent warm sea surface temperature anomalies over the equatorial Indian Ocean played a significant role in modulating the strength of the monsoon Hadley circulation. This in turn affected the onset and intense break spells especially the long break during the peak monsoon month of July. Strong low-frequency intraseasonal modulations with significant impact on the onset and active/break phases occurred in 2002 which were manifested as a good association between low-frequency intraseasonal oscillations and the onset and active/break spells. Further. SST anomalies over the equatorial Indo-Pacific region on low-frequency intraseasonal time scales were found to affect the equatorial eastward and thereby off-equatorial northward propagations of enhanced convection over the Indian region. These propagations in turn modulated the active/break cycle deciding the consequent severity of the 2002 drought.

8 illus, 42 ref

013086   Roy Bhowmik S K;Das A K (NO, India Meteorological Dep, Lodhi Road, New Delhi-110 003) : Rainfall analysis for Indian monsoon region using the merged rain gauge observations and satellite estimates: evaluation of monsoon rainfall features. J Earth Syst Sci 2007, 116(3), 187-98.

Objective analysis of daily rainfall at the resolution of 1° grid for the Indian monsoon region has been carried out merging dense land rainfall observations and INSAT derived precipitation estimates. This daily analysis, being based on high dense rain gauge observations was found to be very realistic and able to reproduce detailed features of Indian summer monsoon. The inter-comparison with the observations suggests that the new analysis could distinctly capture characteristic features of the summer monsoon such as north-south oriented belt of heavy rainfall along the Western Ghats with sharp gradient of rainfall between the west coast heavy rain region and the rain shadow region to the east, pockets of heavy rainfall along the location of monsoon trough/low, over the east central parts of the country, over north-east India, along the foothills of Himalayas and over the north Bay of Bengal. When this product was used to assess the quality of other available standard climate products (CMAP and ECMWF reanalysis) at the grid resolution of 2.5°, it was found that the orographic heavy rainfall along Western Ghats of India was poorly identified by them. However, the GPCC analysis (gauge only) at the resolution of 1° grid closely discerns the new analysis. This suggests that there is a need for a higher resolution analysis with adequate rain gauge observations to retain important aspects of the summer monsoon over India. The case studies illustrated show that the daily analysis is able to capture large-scale as well as mesoscale features of monsoon precipitation systems. The study with data of two seasons (2001 and 2003) has shown sufficiently promising results for operational application, particularly for the validation of NWP models.

6 illus, 18 ref

013085   Ravi V;Rajagopal S (CAS in Marine Biology, Annamalai Univ, Parangipetai-608 502) : Age and growth of the Mudskipper, Bolephthalmus boddarti (Pallas, 1770). J Aquatic Biol 2007, 22(1), 123-8.

Age and growth form the fundamentals for analyzing the mortality, survival rates and recruitments. The mudskippers, Boleophthalmus boddarti (Gobiidae : Oxudercinae) are amphibious, euryhaline and burrowing fishes inhabiting intertidal mudflats of Mudasalodai, Vellar estuary and Pichavaram mangroves.To work out the age and growth, the standard methods were employed. The results indicated that B. boddarti grows up to 82 mm (months mode); 124 mm (probability); and 123.8 mm (von Bertalanffy's) in the first year. In the same order, the second year growth is 135 mm; 158 mm; and 157.9 mm from this region.

3 illus, 1 table, 18 ref

013084   Rastogi R G (Physical Research Lab, , Ahmedabad-380 009) : Indian equatorial electrojet based on the study of Kodaikanal record. Proc Natn Acad Sci India-Sect A 2007, 77(Pt 1), 1-15.

Describes the general features of the equatorial electrojet at Kodaikanal between the years 1950 to 1997. Kodaikanal was close to the centre of the electrojet during the years 1966 - 1974 and slowly shifted to outside the electrojet belt due to the southward movement of the dip equator. The main variation of horizontal field H with a peak around 11 h L T is due to a combined effect of E region ionization maximizing at 1200 h L T and the E region electric field maximizing at 0900 h L T Both H and declination Dw decrease with decreasing ring current index Dst but no apparent relation is seen between vertical field Z and Dst. Disturbance effects on H and D are maximum during equinoctial months. The mean daily variation of the sudden commencement SSC shows a distinct midday maximum for H and midday maxmum for D with no effect on Z. Storm-time variations of Dw and H follow very faithfully the corresponding variations of Dst index. Magnetic storms with maximum phase during midday produce a larger depression in H at Kodaikanal than at Alibag, causing a counter electrojet electrojet events.

16 illus, 26 ref

013083   Rajeev A;Prakash S;Valentin Bhimba B (Microbiology Laboratory, Institute for Coastal Area Studies, Manonmaniam Sundaranar Univ, Rajakamangalam-629 502, Email: bvbhimba@yahoo.co.in) : Antibacterial activity of marine microalgae against multidrug resistant human pathogens. J Aquacult Trop 2006, 21(1-2), 81-6.

Marine microalgal extracts were studied for their antibacterial activity against the multidrug resistant human pathogens. Twenty marine microalgae were cultured and extracts were screened against 10 human pathogens. Among them, Isochrysis galbana extract showed highest percentage of antibacterial activity Among the 5 solvents used for the extraction of antimicrobials, n-butanol showed maximum extraction (41.3%) of antimicrobials. The percentage inhibition of bacterial pathogens by these microalgae showed the maximum inhibition of Escherichia coli.

3 tables

013082   Rai S N;Thiagarajan S (NO, National Geophysical Research Institute, Hyderabad-500 007, Email: snrai@ngri.res.in) : 2-D crustal tehrmal structure along Thuadara-Sindad DSS profile across Narmada-Sion lineament, central India. J Earth Syst Sci 2007, 116(4), 347-55.

Central India is traversed by a WSW-ENE trending Narmada-Son lineament (NSL) which is characterized by the presence of numerous hot springs, feeder dykes for Deccan Traps and seismicity all along its length. It is divided in two parts by the Barwani-Sukta Fault (BSF). To the west of this fault a graben exists, whereas to the east the basement is uplifted between Narmada North Fault (NNF) and Narmada South Fault (NSF). The present work deals with the 2-D thermal modeling to delineate the crustal thermal structure of the western part of NSL region along the Thuadara-Sindad Deep Seismic Sounding (DSS) profile which runs almost in the N-S direction across the NSL. Numerical results of the model reveal that the conductive surface heat flow value in the region under consideration varies between 45 and 47mW/m². Out of which 23mW/m² is the contribution from the mantle heat flow and the remaining from within the crust. The Curie depth is found to vary between 46 and 47 km and is in close agreement with the earlier reported Curie depth estimated from the analysis of MAGSAT data. The Moho temperature varies between 470 and 500°C. This study suggests that this western part of central Indian region is characterized by low mantle heat flow which in turn makes the lower crust brittle and amenable to the occurrence of deep focused earthquakes such as Satpura (1938) earthquake.

4 illus, 1 table, 49 ref

013081   Raghu Kanth S T G;Iyengar R N (Civil Engineering Dep, Indian Institute of Technology, Guwahati-781 039, Email: rk@iitg.ernet.in) : Estimation of seismic spectral acceleration in Peninsular India. J Earth Syst Sci 2007, 116(3), 199-214.

Peninsular India (PI), which lies south of 24° N latitude, has experienced several devastating earthquakes in the past. However, very few strong motion records are available for developing attenuation relations for ground acceleration, required by engineers to arrive at rational design response spectra for construction sites and cities in PI. Based on a well-known seismological model, the statistically simulates ground motion in PI to arrive at an empirical relation for estimating 5% damped response spectra, as a function of magnitude and source to site distance, covering bedrock and soil conditions. The standard error in the proposed relationship is reported as a function of the frequency, for further use of the results in probabilistic seismic hazard analysis.

10 illus, 6 tables, 23 ref

013080   Pati J K;Reimold W U (Plantary Sciences, Nehru Science Centry, Allahabad Univ, Allahabad 211 002, Email: jkpati@yahoo.co.in) : Impact cratering fundamental process in geoscience and planetry science. J Earth Syst Sci 2007, 116(2), 81-98.

Impact cratering is a geological process characterized by ultra-fast strain rates, which generates "extreme shock pressure and shock temperature conditions on and just below planetary surfaces. Despite initial skepticism, this catastrophic process has now been widely accepted by geoscientists with respect to its importance in terrestrial - indeed, in planetary - evolution. About 170 impact structures have been discovered on Earth so far, and some more structures are considered to be of possible impact origin. One major extinction event, at the Cretaceous-Paleogene boundary, has been firmly linked with catastrophic impact, but whether other important extinction events in Earth history, including the so-called "Mother of All Mass Extinctions" at the Permian-TViassic boundary, were triggered by huge impact catastrophes is still hotly debated and a subject of ongoing research. There is a beneficial side to impact events as well, as some impact structures worldwide have been shown to contain significant (in some cases, world class) ore deposits, including the gold-uranium province of the Witwatersrand basin in South Africa, the enormous Ni and PGE deposits of the Sudbury structure in Canada, as well as important hydrocarbon resources, especially in North America. Impact cratering is not a process of the past, and it is mandatory to improve knowledge of the past-impact record on Earth to better constrain the probability of Such events in the future. In addition, further improvement of our understanding of the physico-chemical and geological processes fundamental to the impact cratering process is required for reliable numerical modeling of the process, and also for the correlation of impact magnitude and environmental effects. Over the last few decades, impact cratering has steadily grown into an integrated discipline comprising most disciplines of the geosciences as well as planetary science, which has created positive spin-offs including the study of paleo-environments ana paleo-climatology, or the important issue of life in extreme environments. And yet, in many parts of the world, the impact process is not yet part of the geoscience curriculum, and for this reason, it deserves to be actively promoted not only as a geoscientific discipline in its own right, but also as an important life-science discipline.

18 illus, 122 ref

013079   Patel S C (Earth Sciences Dep, Indian Institue of Techology, Bombay, Mumbai-400 076, Email: scpatel@iitb.ac.in) : Vesuvianite-wollastonite-grossualar-bearing calc-silicate rock near Tatapani, Surguja district, Chhattisgarh. J Earth Syst Sci 2007, 116(2), 143-7.

Reports the occurrence of vesuvianite + wollastonite + grossular + diopside + micro-cline + quartz assemblage in an enclave of calc-silicate rocks occurring within quartzofeldspathic gneiss near Tatapani in the western part of Chhotanagpur Gneissic Complex. The enclave contains phlogopite-absent and phlogopite-bearing calc-silicate rocks, the latter being much more abundant than the former. The above assemblage occurs in the phlogopite-absent rock. Phlogopite-bearing rock contains the assemblage phlogopite + salite + microcline + plagioclase + quartz. A strong schistosity is developed in both the calc-silicate rocks and the minerals are syntectonic with the major foliation-forming event in the area. The vesuvianite-bearing assemblage is formed by amphi-bolite facies regional metamorphism of a calcareous protolith at pressure <60> 4 kbar and X Co₂.

3 illus, 1 table, 12 ref

013078   Panneerselvam C;Selvaraj C;Jeeva K;Nair K U; Anil Kumar C P;Gurubaran S (Equatorial Geophysical Research Lab, Indian Institute of Geomagnetism, Krishnapuram, Tirunelveli-627 011) : Fiarweather atmospheric electricity at Antarctica during local summer as observed from Indian station, Maitri. J Earth Syst Sci 2007, 116(3), 179-86.

Surface measurements of the atmospheric electrical parameters like Maxwell current, electric field and conductivity studied at the Indian station, Maitri (70.75° S, 11.75° E, 117m above mean sea level), Antarctica, during austral summer have been analyzed for the years 2001 to 2004. A total of 69 days were selected which satisfied the `fairweather' conditions, i.e., days with absence of high winds, drifting or falling snow, clouds, and fog effects. The diurnal variation curve of electric field and vertical current averaged for 69 fairweather days is a single periodic with a minimum at 03:00 UT and a maximum near 19:00 UT, which is very similar to the Carnegie curve. The correlation coefficient between these measured parameters has a high value (more than 0.9) for all the days. During fairweather days the measured current and field variations are similar and hence it is clear that the conductivity is more or less stable. During magnetically disturbed days, the dawn-dusk potential drop has clear influences on the diurnal variation and it modifies the conductivity. Apart from the day-to-day variation in low latitude thunderstorm activity, there are diurnal, seasonal, inter-annual variations in the electric potential and the currents, as well as solar influences on the measured parameters. The study will help us to examine the impact of solar and geophysical phenomena like solar flares, geomagnetic storms and substorms on the global electric circuit.

6 illus, 21 ref

013077   Ozel E;Ulug A;Pekcetinoz B (NO, Dokuz Eylul University, Inciralti 353 40 Izmir, Turkey, Email: erdeniz.ozel@deu.edu.tr) : Neotectonic aspects of the Northern margin of the Adana -cilicia subamrine basin, NE Mediterranean. J Earth Syst Sci 2007, 116(2), 113-24.

The sedimentary basins that dominate the north-eastern Mediterranean (Adana-Cilicia basins in the west and Iskenderun basin in the east) are located on the flanks of a partly submerged positive structure (a part of the Africa-Eurasia convergence zone) along which strike-slip faults are evident. This study summarizes the findings of two seismic surveys carried out in the Alanya-Mersin offshore region. Some 850 km of geophysical survey lines were compiled on these cruises. Based on the results determined from these surveys, the north and central part of Adana-Cilicia basin can be subdivided into eastern, central and western structural sub-basins separated by the Ecemis fault complex in the east and the Anamur-Kormakiti structural high in the west at the same time. Results of this study also indicate that Ecemis and Anamur-Kormakiti faults are active. Late Miocene regional compression was responsible for the compartmentation of this complex into the present arrangement and has initiated the rotational regime which has governed subsequent tectonic developments, notably the extensional behaviour of the NE-SW trending Ecemis and Anamur-Kormakiti faults and the transpressive behaviour of the NNE-SSW trending border fault complex.

10 illus, 35 ref

013076   Nethery D;Shankar D (NO, National Institute of Oceanography, Goa-403 004, Email: daniel.nethery@ens.fr) : Vertical propagation of barochlinic Kelvin waves along the west coast of India. J Earth Syst Sci 2007, 116(4), 331-9.

Linear, continuously stratified ocean model is used to investigate vertical propagation of remotely forced, baroclinic Kelvin waves along the Indian west coast. The extent of vertical propagation over the length of the coast is found to be an increasing function of the forcing frequency. Simulations show that, over the length of the Indian west coast, vertical propagation is limited at annual and semi-annual periods, but significant at periods shorter than about 120 days. This has two major consequences. First, the depth of subsurface currents associated with these frequencies varies substantially along the coast. Second, baroclinic Kelvin waves generated in the Bay of Bengal at periods shorter than about 120 days have negligible influence on surface currents along the north Indian west coast.

9 illus, 2 table, 12 ref

013075   Nadarajah S;Choi D (NO, School of Mathematics, University of Manchester, Manchester M60 1QD, UK, Email: saratees.nadarajah@manchester.uk) : Maximum daily rainfall in south Korea. J Earth Syst Sci 2007, 116(4), 311-20.

Annual maxima of daily rainfall for the years 1961-2001 are modeled for five locations in South Korea (chosen to give a good geographical representation of the country). The generalized extreme value distribution is fitted to data from each location to describe the extremes of rainfall and to predict its future behavior. Finds evidence to suggest that the Gumbel distribution provides the most reasonable model for four of the five locations considered. Explores the possibility of trends in the data but find no evidence suggesting trends. Derives estimates of 10, 50, 100, 1000, 5000, 10,000, 50,000 and 100,000 year return levels for daily rainfall and describe how they vary with the locations. Provides the first application of extreme value distributions to rainfall data from South Korea.

11 illus, 5 tables, 26 ref

013074   Mishra V;Quadros G;Athalye R P (NO, WWF-India, 204, National Insurance Buiding, Dr.D.N. Road, Fort, Mumbai-400 601) : Hydrological study of Ulhas river estuary, Maharashtra, India. J Aquatic Biol 2007, 22(1), 97-104.

Hydrological studies on the Ulhas river estuary (18° 45' to 19°16'N and 72°45' to 73°20'E) were carried out at six stations along approx. 40km stretch from its mouth during May 1999 to April 2000. Various parameters had range and overall average as temperature (15.5°C to 34.5°C avg. 26.88°C), suspended solids (0.01g/l to 23g/l, avg. 2.13g/l), pH (6.23 to 8.95 avg. 7.47), dissolved oxygen (0.6 mg/l to 11 mg A, avg. 3.9 mg/l) salinity (0.08ppt to 39.14 ppt, avg. 15.27 ppt), PO-P (0.006 mg/lto 0.805 mg/l avg. 0.120 mg/l), N03-N (1.26 to 31.43 mg/l avg. 4.89 mg/l), Si03-Si (1.65 to 89.43 mg/l, avg. 18.14 mg/l). The comparison with the available past data showed lowering of dissolved oxygen, increased suspended solids and nutrients indicating deterioration of the estuarine ecosystem.

9 illus, 1 table, 31 ref