006156   Ahmad T (Geology Dep, Delhi University, Delhi-110 007, Email: tahmad001@yahoo.co.in) : Precambrian mafic magmatism in the Himalayan mountain range. J Geol Soc India 2008, 72(1), 85-92.

Precambrian mafic magmatic rocks are restricted to the western Himalayas from Himachal in the west through Garhwal to Kumaun in the east. They occur as low-grade volcano-sedimentary sequences of the Lesser Himalaya in the form of volcanic flows intercalated with continentally derived sediments and also as dykes occurring as feeders and some traversing through these sequences. Thus, all the Precambrian mafic magmatic rocks are not contemporary but may represent more than one magmatic episode. However, it is not very clear how much is the gap between the individual magmatic phases. In addition to the low-grade sequences, mafic magmatic rocks are also recorded from the Chail, Jutogh and Vaikrita Groups and their equivalents in Garhwal and Kumaun regions. In these three sequences the mafic magmatic rocks are represented by amphibolites which occur as shapeless bodies, boudins, disrupted dykes/sills varying in size from 1-2 m in thickness and 3-5 m in width. The basic rocks of all the units consist of clinopyroxene (augite and ferro-augite) and plagioclases as the dominant phases with minor olivine (now serpentine). Commonly observed secondary phases include amphiboles, chlorite, opaques, epidote, quarts, biotite and titanites. Geochemical data indicates that these rocks are compositionally basalt and basaltic -andesites. They have typical tholeiitic lineage with Fe-enrichment and are classified as low-Ti tholeiites. Rare earth elements (REE) and incompatible trace elements data indicate enriched light rare earth element (LREE) - large ion lithophile elements (LILE) and depletion of high field strength elements (HFSE) characteristics for the mafic rocks of the lower grade Lesser Himalayan sequences, Chail and Jutogh Groups. The mafic rocks of Vaikrita Group, on the other hand show nearly flat REE and incompatible trace elements patterns with distinct positive Sr-anomaly, which is very different from the other groups. These characteristics indicate derivation of Vaikrita mafic rocks from different sources compared to the other samples. Lithological association and geochemical characteristics indicate derivation of the mafic magmatic rocks from enriched lithospheric mantle sources by varying degrees of partial melting followed by clinopyroxene±minor olivine±plagioclases±opaques in a rift tectonic environment.

5 illus, 48 ref

006155   Ahmad A H M;Bhat G M;Jehan N;Khan A F;Majid A (Geology Dep, Aligarh Muslim Univ, Aligarh-202 002, Email: ahmahmad2004@yahoo.com) : Tectono-Provenance and Diagenesis of Habo dome sandsotne, chari formation, Kachchh, Western India. J Geol Soc India 2008, 72(6), 790-800.

The Habo Dome Sandstone of Chari Formation has been analyzed for petrofacies and diagenetic history. The sandstones are generally medium to coarse grained and moderately to well sorted. These sandstones are composed of several varieties of quartz, feldspar, rock fragments, micas and a suit of heavy minerals derived from the Aravalli Range and Nagarparkar massif. The petrofacies analysis reveals that these sandstones belong to the continental block, recycled orogen and rifted continental margin tectonic regime. During mechanical compaction rearrangement of grains took place and point and long contacts were formed. The sandstones were cemented by calcite, iron oxide, silica, chalcedony and glauconite cements in order of abundance. Different graphs of porosity versus depth suggest a depth of burial in the range of 615 to 769 m.

7 illus, 4 tables, 27 ref

005322   Yadav D N;Joshi M R (Back-End Technology Development Div, Bhabha Atomic Research Centre, Mumbai-400 085, Email: dny@barc.gov.in) : Geo-hydrological study of groundwater recharge using <. J appl Geochem 2008, 10(2A), 630-9.

Study on estimation of groundwater recharge rate, an important hydrological parameter of radioactive disposal site, Near Surface Waste Disposal Facility (NSDF), Trombay was carried out as apart ofgeo-hydrological site characterization program in 2003. The methodology followed in the study aimed at estimating in-situ groundwater recharge rate by injecting radio-tracer ^{3H in the ground before onset of monsoon season followed by its tracking vertical movement in the soil profile during the post monsoon season. After the tracer injection, 1.3 m deep soil profile was taken for regular interval analysis of soil-moisture and radio-assay of tritium contents in laboratory. Out of the five soil-profiles, only one could show the vertical movement of tracer. Based on vertical shift in peak tritium activity to an extent of 47.5 cm, average moisture content of 13.83% and average bulk density 1.7 g/cc of soil, the groundwater recharge per annum was calculated to be 9.81 cm. The estimated recharge rate for this soil profile is about 4% of the average annual rainfall, which is well within the range reported for the hard rock aquifers. Except this soil profile, the injected tritium tracer could not be traced in most of the profiles indicating a possible migration loss through fractures/joints present in the weathered rock layer.}

6 illus, 2 tables, 14 ref

005321   Surya Prakash Rao K;Naqvi S A S;Divakara Rao V;Babu R (Applied Geochemistry, Osmania Univ, Hyderabad, Email: ksprao1939@yahoo.co.in) : Priliminary report on defluoridation using weathered fly-ash. J appl Geochem 2008, 10(2A), 654-9.

Excess fluorine in water and/or soil is a health hazard and large number of fluorosis cases is being reported from many parts of the country especially from Andhra Pradesh. The effects of excess fluoride on the bones, teeth and other human organs are well documented and many methods were suggested to remove such excess F and implemented with partial success. Such methods include the Nalgonda technique, Activated alumina, Ion-exchange, Reverse osmosis, etc. Defluoridation using weathered fly-ash is attempted by the authors as a part of the project sponsored by Ramagundam Super Thermal Power Station (RSTPS) on fluoride contamination in and around thermal plant. Rock, soil and water samples from an area of 20 sq. km around RSTPS, Ramagundam were collected on a grid pattern for three successive years covering both the pre-monsoon and post-monsoon. The fluoride shows random distribution in general and a slight decreases in the post-monsoon. Weathered fly-ash from RSTPS was collected and homogenized. The initial pH and F contents were recorded along with the samples to be experimented and standard fluoride water. Defluoridation studies show gradual decrease of F both in sample and the standard fluoride solution, with water recording substantial reduction (from 20.7 mg/1 to 3.7 mg/1 in 24 hours) without change in the quality of water. The experimental details and the results are reported and further remedial Measures suggested.

1 illus, 2 tables, 8 ref

005320   Subba Rao M V;Ramesh S K;Suresh K; Satyanarayanan M;Keshav Krishna A;Dasaram B (National Geophysical Research Institute (NGRI), (Council of Scientidic and Industrial Research), Uppal Road, Hyderabad, Email: subbaraomv1950@yahoo.com) : Geochmistry of the mafic dykes in the basaltic terrain of the deccan volcanic povince (DVO) in the ambadongar region, Gujarat: some petrogenetic aspects and reflections on the mantle source regions. J appl Geochem 2008, 10(2A), 571-81.

Basaltic terrain of the Ambadongar region in Gujarat is interspersed with numerous dykes of different orientations. Results of the studies carried out on the petrographic and geochemical features of these dykes are presented and the petrogenetic implications vis-a-vis the nature of the mantle source regions of the dykes are discussed. The dyke rocks are made up of plagioclase laths with radial as well as irregular arrangement and amphiboles with occasional presence of pyroxenes and the occurrence of a few opaques. The tholeiitic character of these dykes is attested by the (Na₂O+K₂O)-FeO^t-MgO relationships. These dolerite dykes have only moderate levels of rare earth element (REE) contents, showing limited fractionation as seen from La_N/Sm_N and Gd_N/Yb_N, ratios. No prominent Eu anomalies are discernible (except in a few samples, having negative anomalies). Relative to the primitive mantle the dykes exhibit strong positive spikes in Nb, Ta, Rb and Ba, while U, K, P and Ti have negative anomalies, suggesting a mantle-plume material as source for these dykes. Lower levels of ferro-magnesian trace elements such as Cr, Ni and Co is consistent with their overall tholeiitic nature and the influence of plume material in their petrogenesis.

7 illus, 2 tables, 10 ref

005319   Singh R P;Tewari R R;Dangwal D N;Mahata P K; Singh D K;Soni R;Jyoti;Sharma K K (NO, K.D.M. Institute of Petroleum Exploration, ONGC Ltd., Dehradun-248 195) : Application of adsorbed gas analysis technique for prediction of hydrocarbon signature in Dehradun re-entrant area of Himalayan foot hills. J appl Geochem 2008, 10(2A), 455-62.

Deals with adsorbed gas analysis carried out in re-entrant of Himalayan foot hills which has many eas seeps through faults and fractures. Geochemical surface prospecting was carried out in this area by adsorbed gas analysis of 745 soil samples and values of hydrocarbons ratios are used to determine the nature of subsurface hydrocarbon deposits. The relative presence of C₂+ hydrocarbon gases indicate thermogenic origin of the gases which is supported by the hydrocarbon ratio values. The hydrocarbon ratio C₁/C₂+C₃<60>10 indicates emanation from a mature source. The values of C₂/C₃ less than 1.3, C₁/ ∑C_n between 95-100, C₁/C₂ between 10 to 20 and C₃/C₁* 1000 between 20-60 indicate that the seeped gases have migrated from gas/condensate subsurface pool. The adsorbed gas analysis in KNS and LNG areas indicates moderate anomaly whereas in RNP area it shows good anomaly. However, MHD area is not very prospective.

4 illus, 1 table, 8 ref

005318   Singh B K;Jain A;Sumit Kumar;Tomar B S;Tomar R;Manchanda V K;Ramanathan S (School of Studies in Chemistry, Jiwaji Univ, Gwalior, Madhya Pradesh-474 011, Email: radha_tomar11@yaho.co.in) : Synthesis, characterization and role of magnetite in Cs migration in environment: effectof humic acid. J appl Geochem 2008, 10(2A), 507-13.

Sorption of ^{137Cs on colloidal sized magnetite particles synthesized by solution route was investigated at varying pH values both in the absence and presence of Aldrich humic acid. Percentage sorption of cesium on magnetite was found to be negligible up to pH 6 above which it increased gradually. Humic acid was not found to have any effect on the sorption of cesium on magnetite colloids, which was attributed to the negligible interaction between cesium and humic acid.}

5 illus, 8 ref

005317   Saxena R K;Shukla M K;Bhandari M;Prasad B; Singh R R (NO, , KDMIPE, Oil and Natural Gas Corporation Ltd.(ONGC), Dehradun-248 195, Email: rksaxena2@yahoo.co.in) : Episodic filling of multi layer reservoirs of gandhar field, South Cambay basin, India. J appl Geochem 2008, 10(2A), 433-54.

Gandhar field is located in rising northwestern flank of Broach depression of South Cambay Basin. India. Oil is being produced from Hazad members consisting of twelve individual sand units from GS-I to GS-XI1. All sands of Gandhar field except GS-X bear hydrocarbons. In GS-VI and VII sands few wells produced gas/condensates only. A suit of oils from stacked reservoirs (different sands) has been analysed by various geochemical techniques for molecular information to establish correlation among the oils producing from different sands of Gandhar field. Chemical parameters considered for oil to oil correlation are stable carbon isotope ratio and biomarker composition including Pr/Ph, isoprenoid/ n-alkane. sterane and terpane ratios in addition to bulk parameters. The analysis has established four distinct groups of oils. Group A oils (GS-I to GS-III sands), Group B oils (GS-VIII and GS-IX sands), Group C oils (GS-XI and GS-XII sands) and Group D oils (GS-IV to GS-V sands). The Group D oils showed intermediate characteristics to that of Group A and B oils. The maturity based geochemical parameters of Miulied oils reveal generation from peak oil generation stage of source rock. The integration helped in evolving a predictive model of origin, migration and accumulation of hydrocarbon in the Gandhar field. The molecular level geochemical analysis of produced oils from various sands of Gandhar field suggests multiple charge process for oils to fill each reservoir over the extended period of time.

12 illus, 5 tables, 0 ref

005316   Sawai B K;Shirase K N;Idnani R C;Tharkar A R; Haval R G;Hattargi S S;Joshi R G;Dalvi P B (NO, Maharashtra Jeevan Pradhikaran, Mumbai) : Post disaster-management of water supply of Ambernath and Badlapur cities. J Indian Wat Wks Ass 2008, 40(2), 85-91.

During disaster, management of essential services is a daunting task. Water supply systems (WSS) are susceptible to natural disasters like earthquakes, floods, and famine and also face threat from man- made disasters. Since water is the basic need of living being, restoring it is a major challenge to water engineers in such scenarios. In such events, engineers learn lessons and take precautionary measures to avoid threats from such disasters. Ambernath Badlapur WSS faced the flood damage after unprecedented rainfall of 26 July 2005. The system collapsed due to failure of the source. Engineers from Maharashtra Jeevan Pradhikaran (MJP) restored water supply within a week's period after great hard work. However, functioning of water supply system post disaster is an important aspect of any WSS. A case study of post disaster work of Ambernath Badlapur WSS is presented here.

8 illus, 6 ref

005315   Roonwal G S (NO, Inter-Univ Accelerator Centre (AMS Group), Aruna Asaf Ali Marg, Post B, ) : New trends in exploration for marine minerals. J appl Geochem 2008, 10(2A), 582-92.

Ocean scientists community has been active in the past decade accessing the deep ocean and shallow seas from pioneering efforts of Human Occupied Submersible (HOV) to much improved remotely operated vehicles (ROVs) for precise research plans. The Ocean Floor Observation System (OFOS) through its on-line observations is of much help in our exploration and mineral assessment programme. The newest attempt has been the development of Autonomous Underwater Vehicle (AUVs) in this technology for improvement of aim. Likewise, the mining equipment is being developed in a way that would do minimum disturbance to the marine life. Continues to respond to the challenge of engineering technology always aiming to enhance efficiency and personnel safety. Deep sea floor contains the well known ferromanganese nodules, cobalt rich ferromanganese crusts, metalliferous muds, metal impregnation as well as hydrothermal sulfides on the mid-oceanic ridges. These resources will be explored with an aim to exploit in the future. Trends in exploration for metallic minerals in the sea floor have been discussed.

10 illus, 13 ref

005314   Razdan P N (Geological Survey of India, , Northern Region, Lucknow-226 024, Email: pnrazdan@gmail.com) : Geochemistry of geothermal energy resources and their potential in India. J appl Geochem 2008, 10(2A), 532-44.

Geothermal Energy is the vast reservoir of heat energy in the earth's interior, whose surface manifestations are the volcanoes, fumaroles, geysers, steaming grounds and hot springs. It can be recovered and exploited economically. Even in the pre-historic days, early humans possibly used the hot water from 'thermal springs' for simple purposes like cooking and washing. The other crustal manifestations were possibly viewed with reverential awe. Each geothermal system has its own structural setup, hydrological, geochemical and enthalpy characteristics. Based on the studies of structural setup, hydrology, geochemistry, geophysical studies and exploratory drilling, the geothermal systems can be classified for the purpose of energy exploration. However, on the basis of enthalpy characteristics the geothermal systems in India, are classified into medium (100 °C-200 °C)-and low enthalpy (<60>100 °C) geothermal energy resources/systems.

3 illus

005313   Rawat D S;Bhatnagar A K;Goswami B G;Singh R R (NO, KDM Institute of Petroleum Exploration, ONGC Ltd, 9, Kaulagarh Road, Dehradun-248 195, Email: dsr7815@rediffmail.com) : Petroleum geochemistry of oils and condensates of Kesanapalli west field, Krishna-Godavari basin, India. J appl Geochem 2008, 10(2A), 417-32.

Geochemical study indicates that the relative abundance of saturated hydrocarbons in Tertiary oils and condensates of Kesanapalli west field is predominantly aliphatic in nature. These oils and condensates are characterized by dominance of C₃₀ hopane over C_M hopane, and C₂₉ sterane over C₂₈ and C₂₇ steranes and presence of complete range of ubiquitous hopancs with the decreasing concentration of the homohopanes with higher homologues. They are also characterized by the higher concentration of oleanane and high Pr/Ph ratio. These characteristics suggest that these oils and condensates are generated from predominantly terrestrial source organic matter with significant contribution from higher angiospermic plants deposited in oxic environment. All the studied oils/condensates are of moderate maturity. Based on molecular parameters, two oil families have been identified in the Kesanapalli west. Group-1 oils have higher oleanane concentration and C₂₉hopane/C₃₀hopane ratio while group-2 oils have lower values for these parameters. Ihesc differences in biomarker distribution clearly indicate that there are distinct variations in the organoiacies for ihcsc two groups of oils. Thus, the existence of two different oil-source families in the study area has significant implications for further exploration in the area.

10 illus, 3 tables, 10 ref

005312   Rao P N;Kalita P;Mazumdar N (Central Ground Water Board, Southern Region, , Hyderabad, Central Ground Water Board, NER, Guwahati, Email: pnrao_1960@yahoo.co.in) : Occurrence of high concentration of fluoride and its genesis in ground water in eastern part of Karbi Anglong district, Assam, India. J appl Geochem 2008, 10(2A), 640-53.

Ground water in eastern part of Karbi Anglong district, Assam is found to have high fluoride concentrations. Major part of the area is hilly terrain underlain by consolidated formations belonging to Archaean Gnessic Complex and Shillong Group formations of Pre-Cambrian age, semi consolidated formations of Tertiary period while a small part is occupied by unconsolidated formations comprising valley fill and alluvial sediments in topographic depressions. The area falls in tectonically disturbed zone. Deep seated major faults extending several kilometers traverse the area. Valley fill deposits possess higher concentrations along valley margins in the Parakhowa-Dengaon, Baghpani-Dentaghat, Ramsapathar-Longnit-Kheroni areas. Highest fluoride concentration of 20.6 mg/L is at Ramsapathar deep tube well. Shallow aquifer zones are devoid of fluoride while deep horizons showed excessive fluoride without any trend with depth and pattern in geographical distribution. This is attributed to the irregular disposition of aquifer zones and their interconnectivity to the source minerals in Archaean granite and pegmatitic rocks occurring on adjoining high altitude recharge areas through deep seated fractures, aquifers nearness to the deep seated fault zones and ground water recharge. High Sodium/chloride ratio in ground water conclusively prove that source is sodium fluoride mineral. High fluoride content of 8.7 mg/L in thermal spring at Garampani fault zone, uncommon occurrence of higher values of fluoride suggest that prevailing high temperatures and pressure conditions in deep seated faults could have facilitated in release of fluoride from source mineral under favourable hydrochemical conditions.

4 illus, 3 tables, 22 ref

005311   Pattanayak S;Mohanty U C (Centre for Atmospheric Sciences, Indian Institute of Technology, New Delhi, Email: mohanty@cas.iitd.ernet.in) : Comparative study on performance of MM5 and WRF models in simulation of tropical cyclones over Indian seas. Curr Sci 2008, 95(7), 923-36.

Tropical cyclone is one of the most devastating and deadly weather phenomenon worldwide. It is a result of organized intense convective activities over warm tropical oceans. In recent years mesoscale models are extensively used for simulation of genesis, intensification and movement of tropical cyclones. In this study, the recent three very severe cyclonic storms generated over Indian seas (Bay of Bengal and Arabian Sea) are considered. During 26-29 April 2006, a very severe tropical cyclone, known as Mala, developed over the Bay of Bengal and crossed the Arakan coast of Myan-mar on 29 April 2006. During 2-7 June 2007, a super cyclonic storm, known as Gonu, developed over the Arabian sea and crossed the Makran coast on 7 June 2007. During 11-16 November 2007, a very severe cyclonic storm, known as Sidr, developed over the Bay of Bengal and crossed the Khulna-Barisal coast of Bangladesh on 15 November 2007. In the present study, two state-of-the-art mesoscale models, MM5 and WRF, developed at the National Center for Atmospheric Research (NCAR), USA, have been used to evaluate the performances of both the models in the simulation of the above-mentioned tropical cyclones. The performances of both the models have been calculated by integrating with 15 different initial conditions, i.e. each case with five different initial conditions. A number of meteorological fields, viz. central pressure, wind and precipitation have been verified against observations/ verification analyses. The vector displacement error in track forecast has also been calculated using the best track provided by the India Meteorological Department. The results indicate that the WRF model has better performance in respect of track and intensity prediction than the MM5 model.

12 illus, 6 tables, 18 ref

005310   Paropkari A L (NO, National Institute of Oceanography, Dona Paula, Goa-403 004, Email: parop@nio.org) : Abiogenic origin of petroleum hydrocarbons: need to rethink exploration strategies. Curr Sci 2008, 95(8), 1018-20.

27 ref

005309   Paik S G;Yun S G;Park H S;Lee J H;Ma C W (Marine Ecosystem and Environment Research Div, Korea Ocean Research and Development Institute, Ansan P.O. Box 29, 425-600, Korea, Email: sgyun@daegu.ac.kr) : Effect of sediment disturbance caused by bridge construction on macrobenthic communities in Asan bay, Korea. J envir Biol 2008, 29(4), 559-66.

Changes in soft-bottom macrobenthic communities and the effects of anthropogenic disturbances were studied. We compared biological and environmental samples during and after bridge construction (DBC and ABC). Significant differences were detected in sediment composition at three stations, although hydrographic conditions were similar for DBC and ABC samples. From DBC to ABC, the number of species and density of macrobenthic fauna tended to decrease, whereas biomass increased. Non-metric multidimensional scaiing (MDS) analysis identified two sampling period groups from eight temporal samples, plus three station groups and one station from 12 spatial samples, which corresponded to macrobenthic faunal assemblages and their characteristic species. In addition, contributions of variables to similarity showed that the DBC and ABC samples differed significantly in the distribution of characteristic species and proportion of polychaete trophic groups, suggesting that the macrobenthic community structure was a factor affecting sediment disturbance caused by bridge construction.

7 illus, 3 tables, 47 ref

005308   Lahkar A F;Das P K (Geology Dep, Arya Vidyapith College, Guwahati-781 016) : Geochemistry of some tertiary coals occurring in Dilli area, Sivasagar district, Assam. J appl Geochem 2008, 10(2A), 519-31.

Coals are non-caking to weakly caking and of medium grade. They are perhydrous in nature and high sulphur content in the coals indicates that they were probably deposited in a marine-influenced deltaic lagoonal environment. The coalification of these coals is close to bituminous as they were formed in the overthrust zones of the belt of Schuppen. The carbon and moisture contents of these coals indicate they are mature in nature which can be attributed to a more intense and probably more sudden dynamic process. These intense dynamo-chemical processes were the result of severe mountain building activity in the geosynclinal basin where they were deposited. The interrelationship of the important constituents of coals show good correlation.

10 illus, 7 tables, 16 ref

005307   Kim Y S;Choi H G;Nam K W (School of Marine Life Science, Kunsan National Univ, Kunsan, Jeonbuk 573-701, Korea, Email: kimys@kun) : Seasonal variations of marine algal community in the vicinity of Uljin nuclear power plant, Korea. J envir Biol 2008, 29(4), 493-9.

Three marine algal sites were examined seasonally in an area of thermal discharge from the Uljin nuclear power plant in Korea to assess possible Tffipacts from thermal stress. Quadrat samples were taken at three sites: cooling water intake, outfall and Chukbyon. The degree of wave exposure increased from intake, outfall to Chukbyon. Percent cover and biomass were response variables. All sites were, by numbers red algae, followed by brown and green algae. Over the year, the maximum species diversity was also found at the Chukbyon (2.39), but the minimal one (1.67) was observed at the outfall. Seasonally, generally among algal form-functional groups, filamentous and coarsely branched algae were most abundant throughout the year at the three sites. The number of species in the jointed calcareous groups increased remarkably at the outfall. Based on these results, species richness appears to be strongly affected by wave exposure and thermal stress. The higher proportion of calcareous form groups at the outfall sites indicates that these species are better adapted morphologically to thermal stress such as high temperatures.

4 illus, 2 tables, 56 ref

005306   K'Orowe M O;Singh V S;Anand Rao V;Dhakate R (NO, Jomo Kenyatta Univ of Agriculture and Technology, P.O. Box 62000, Nairobi, Kenya, Email: modondi@yahoo.com) : Geoelectrical characterization of zones of disintegration in a crystalline basement environment. Curr Sci 2008, 95(8), 1067-71.

Attempt has been made in this study to characterize the subsurface basement structures in the Jangoan watershed in the Waipalli Basin, Nalgonda District, Andhra Pradesh, India, for identification of zones of disintegration, which are potential aquifers, using geophysical techniques. Results from resistivity inversion and tomography have been studied. A processing procedure here referred to as pseudo resistivity index parameter was initiated for characterization of basement rocks.

9 illus, 6 ref

005305   Jung S (NO, National Fisheries Research and Development Institute, 408-1, Sirang-ri, Gijang-gun, Busan, 619-902, Republic of Korea, Email: sukgeum.jung@gmail.com) : Spatial variability in long-term changes of climate and oceanographic conditions in Korea. J envir Biol 0000, 29(4), 519-29.

Evaluated long-term changes in hydrological conditions (temperature, salinity and dissolved oxygen) in Korean sea waters in relation to the regional land climate change (airtemperature and precipitation) based on available meteorological and oceanographic data. Regression analyses, spatial patterns and cross-correlations on the climatologic and hydrological factors suggested that industrialization processes and related urban heat-island effects during the past 37 years from 1968 to 2005 in South Korea have increased land surface temperatures by 1.267°C, at least for the urban areas, and subsequently increased sea surface temperatures by 0.975°C and decreased salinities by 0.229. The influence of land surface temperature on the sea water temperature reached at least 75-m depth. Regarding the causality in the land-ocean climate changes, air-temperature changes preceded sea water temperature change by 0-2 months in spring and summer, but the sequence could be reversed, possibly because of potential heat held by the ocean. This study demonstrated that human factors have been driving warming influences on regional sea waters, impacting marine ecosystems and changing dominant fish species in commercial fishery catches of Korea.

10 illus, 2 tables, 28 ref

005304   Jayangondaperumal R;Thakur V C;Suresh N (Centre for Geotechnology, M.S. Univ, Tirunelveli-627 012, Email: thakurvc@wihg.res.in) : Liquefaction features of the 2005 Muzaffarabad-Kashmir earthquake and evidence of palaeoearthquakes near Jammu, Kashmir Himalaya. Curr Sci 2008, 95(8), 1071-7.

Studied the earthquake-induced ground deformation features like fractures and landslides associated with the 2005 Muzaffarabad-Kashmir earthquake. During the study weipbserved well-developed liquefaction features at Simbal camp, about 20 km south of Jammu. Authors excavated small trenches for palaeoseis-mological study at the site, has been recorded two palaeo-earthquake events (I and II) of sand injections prior to the sand blows of the 2005 earthquake. Two palaeo-earthquakes events have been interpreted in the trench. Event-II is assigned an age of 2000 yrs BP (i.e. beginning of the first millennitim) and the event-I occurred during AD ~1100. The Main Boundary Fault, locally called the Riasi thrust, lies along the southeastern extension of the Balakot-Bagh Fault. The liquefaction features are located around ~ 240 km SE of the epicentre of the 2005 event, and may have been produced due to favourable ground conditions and dynamic stress transfer, as the rupture and stress are reported to have propagated to the SE from the epi-central area.

5 illus, 1 table, 24 ref

005303   Jain S K (NO, National Institute of Hydrology, Roorkee-247 667, Email: skj@nih.ernet.in) : Impact of retreat of gangotri glacier on the flow of Ganga river. Curr Sci 2008, 95(8), 1012-14.

1 table, 6 ref

005302   Gin S;Verney-Carron A;Libourel G (CEA, , Marcoule, France) : Use of natural and archaeological analogs to validate long-term behaviour of HLW glass in geological disposal conditions. J appl Geochem 2008, 10(2A), 500-6.

Some old basaltic and Roman glasses have been studied in order to validate the predictive models developed for assessing the long-term behaviour of nuclear glass in geological repository conditions. Leaching behaviour of basaltic glass altered in both laboratory and natural environment conditions allows to validate the key mechanisms that control glass dissolution kinetics and the order of magnitude of glass packages lifetime in a stable clayey formation (French reference concept for a geological disposal of high level waste). Study of Roman glass blocks (with the same geometry as nuclear glass package) altered during 1800 years in a marine environment gives new insight on the basic mechanisms involved in confined media (fractures and small cracks). Results show the importance of the coupling between transport of reactive species and chemical reactions. Study, still in progress, would allow to validate the modelling of such a complex system.

3 illus, 1 table, 11 ref

005301   Dinesh A C;Jayaprakash C (NO, , Marine Wing, Geological Survey of India, Mangalore-575 001, Email: acdinesh@rediffmail.com) : Zaherite - the key mineral in alleppey mudbank formation and on the possibility of creating mudbanks artificially. Curr Sci 2008, 95(7), 962-6.

X-ray diffraction and chemical analysis of Alleppey mudbank sediments have shown the presence of zaher-ite (Al₁₂(SO₄)₅(OH)₂₆.20H₂O), which has not been reported from this area so far. Mudbank sediments are characterized by abnormally high water content. Clay particles are randomly oriented due to the presence of zaherite, making them extremely porous. The porous mud at the top and consolidated mud at the bottom with transitional boundary in between is collectively called as 'dispersed mud', which is responsible for wave damping and mudbank formation. If zaherite or similar type of mineral can be introduced in the required proportion into the clay, it may be possible to create mudbanks artificially.

6 illus, 3 tables, 16 ref

005300   Dhurandhar A P;Pramod Kumar;Majumdar A; Umamaheswar K (Atomic Minerals Directorate for Exploration and Research, Atomic Energ, , Nagpu-440 001) : Spatial and temporal variability of hydrogeochemical patterns around Wahkyn uranium deposit, Meghalaya. J appl Geochem 2008, 10(2A), 593-629.

Spatial and temporal controls on major ion and trace elements stream water and borehole water chemistry are assessed using hydrogeochemical survey data for the area around Wahkyn Uranium Deposit, Meghalaya. Spatial variations in stream water chemical composition are interpreted in relation to the environmental chemistry of the major ions and trace elements and controls such as pH, Eh, bedrock geology, weathering processes and atmospheric inputs. Imaging of hydrogeochemical data and dissolved mineral species reveal the spatial and temporal variation patterns. Bedrock geology, atmospheric input and weathering processes can satisfactorily explain compositional variation in the hydrochemical data set.

9 illus, 6 tables, 64 ref

005299   Dhakate R;Singh V S (NO, National Geophysical Research Institute, Uppal Road, Hyderabad-500 007, Email: dhakate_ratnakar@yahoo.com) : Identification of water-bearing fractured zones using electrical conductivity logging in granitic terrain, Andhra Pradesh, India. Curr Sci 2008, 95(8), 1060-6.

Application of EC (electrical conductivity) logging was carried out to precisely delineate fractured zones in hard-rock terrain. The experiment was carried out in three different phases, viz. before pumping, during pumping and during the recovery period of the wells. The purpose was to excite the aquifer system to enhance the response into the well. EC logging was performed in a well that was chosen in the vicinity of the pumping well. All the necessary precautions and measurements is required for the pumping test were taken. Changes were observed in the EC values at certain depths, which was attributed to the presence of waterbearing fractured zones. The results were correlated with information collected during the field investigation and geophysical studies. EC logging also provides other information such as hydrochemical information, water quality and water-rock interactions. Out of six EC loggings carried out in the study area, three showed changes in the EC values in the water-bearing fractured zones, while the other three did not show any changes until the depth of the borewells.

5 illus, 3 tables, 17 ref

005298   Chetia M;Singh S K;Bora K;Kalita H;Saikia L B;Goswami D C;Srivastava R B;Sarma H P (Defence Research Laboratory, Defence Research and Development Organization, Tezpur-784 001, Email: mail-mridul_chetia@rediffmail.com) : Groundwater arsenic contamination in three blocks of Golaghat district of Assam. J Indian Wat Wks Ass 2008, 40(2), 150-4.

Contamination of Groundwater by arsenic and its adverse effect on human being have been reported in 20 countries in different parts of the world. The magnitude is considered highest in Bangladesh followed by India, Mongolia, China and Taiwan. Groundwater arsenic contamination has raised its ugly head recently in Assam, India, where people are thought to be at risk due to continuous consumption of arsenic rich water. Arsenic concentration in groundwater samples from the three blocks viz. Dergaon (Golaghat North), Kathalguri (Golaghat Central), Podumoni (Golaghat East) of Golaghat district of Assam is presented here to access their suitability for potable purpose. Water samples from the above mentioned blocks of Golaghat district of Assam were analysed for arsenic, iron andpH. It was observed that arsenic content of these samples varied from 0.001 ppm to 0.073 ppm or rng/L and arsenic content of about 39.72% samples were beyond the permissible limit (0.01 ppm) for drinking use. Maximum concentration of arsenic was observed at 0.073 ppm from Podumoni block. pH of these samples varied from 5,9 to 8.1 and iron from 0.28 ppm to 5.88 ppm. Statistical analysis of data reveals that correlation between arsenic and iron content of analysed water samples non significant (r=0.168).

1 illus, 2 tables, 15 ref

005297   Chand T;Negi B S;Harvir Singh;Prasad I V S V; Singh R R (NO, KDM Institute of Petroleum Exploration, Oil and Natural Gas Corporation Limited Kaulagarh Road, Dehradun-248 195, Email: chand_trilok@ongcl.com) : Hydrocarbon accumulation in miocene sequences, a case study of Ahmedabad block, Cambay basin. J appl Geochem 2008, 10(2A), 401-16.

Study is an attempt to systematically evaluate Miocene sequence in Ahmedabad block, Cambay Basin for hydrocarbon accumulation as well as migration paths and to assess the quality of the regional seal, which is Tarapur Formation in the area. Rock-Eval and GC data have been generated on 832 cuttings/core samples of Miocene sequence from 37 wells in Aluneciabad block of Cambay Basin. Free hydrocarbons S1 (mg HC/g rock), total organic content (TOC%), Production Index (PI). extractable organic matter EOM (mg/g rock) and GC fingerprints of saturate fractions of extracted bitumen are used to identify hydrocarbon accumulations in the studied area. Absence of significant values of S1, P1 and EOM in Miocene Formation in the well Gamij-M, Kalol-O, Asmali-Y, Indrora-H, Sanand-U and Wasna-B which are producing from Kalol revealed that Tarapur Formation might have acted as a perfect seal. Rock-Eval parameters SI and PI, EOM and GC fingerprints indicate that depth intervals 960 - 965 m and 1060-1065 m (Kalol no. Q), 700-705m(Wasna no. A), 630-640m (Nawagam no. U) and 635-640m (Sanand no. R)'in Miocene show hydrocarbons accumulation in Miocene. The genetic correlation of bitumen of Miocene and Pre-Tarapur sediments in the wells Wasna-A, Kalol-Q, Nawagam-U and Sanand-R suggest that the area around these wells is promising from hydrocarbon exploration point of view in Miocene. Log data also corroborate with the above findings.

14 illus, 1 table, 11 ref

005296   Bhardwaj K N;Tiwari S C (Botany and Microbiology Dep, Post Box 22, H.N.B. Garhwal Univ, Srinagar, Garhwal-246 174, Email: kailash0011@rediffmail.com) : Geothermal energy resource utilization: perspectives of the Uttarakhand Himalaya. Curr Sci 2008, 95(7), 846-50.

Developing world community is struggling with scarcity of power. Most of its power is derived from non-renewable conventional energy resources which are decreasing day by day. Therefore, presently renewable energy resource utilization is the best solution to combat this problem. Geother-rnal energy is one such renewable energy resource which is still unexplored. Besides, there are other potential applications of this energy resource waiting to be explored. It is second to none in its applicability and environment-friendly aspects when compared to other contemporary energy resources. In the present article, attempts have been made to describe the multi-dimensional utilization of geothermal energy resource as far as India or in particular, the Uttarahhand Himalaya is concerned. This remote region is India's most promising geothermal province. The present energy scenario in India needs special attention to explore geothermal energy.

1 illus, 1 table, 13 ref

005295   Basilio A P (NO, , Manila Water Co., Philippines, Email: abe.basilio@manilawater.com) : Manila water NRW reduction story. J Indian Wat Wks Ass 2008, 40(3-4), 175-82.

The Manila Water experience in NRW Reduction is not purely technical issue, but involves a strong management framework and an effective Private-Public Partnership. Breaking the system into manageable areas, known as territories or zones provides a good management framework to diagnose and effect solutions to water losses, be it commercial or physical. The Territory Management Concept exemplifies Manila Water's principle of on-ground management. The concept enabled a clearer diagnosis of the area and for each territory manager to engage closer ties with the communities. An NRW Reduction Program requires a range of skilled staff, empowered managers and technically equipped engineers who are rarely available. The assignment of Corporate Program Coordinators (CPC's) enables skills improvement of targeted personnel and awareness of the whole company. The CPC's role as enabler allows Best Practices and standards to be shared and practiced throughout the system. But the most important part of the program is the involvement and the commitment of the community during and after the project completion. Manila Water Company's NRW reduction program has brought down its NRW from 63 % in 1997 to its current state (2008) at 20%. Moreover, access to 24 hour supply has dramatically improved even in the most depressed areas in the concession area. The NRW reduction program of water operators can only succeed with the commitment of employees and cooperation/involvement of customers as well.

13 illus, 1 table

005294   Balaram V (NO, National Geophysical Research Institute, (Council of Scientific and In, Hyderabad-500 606, Email: balaramv1951@yahoo.co.in) : Analytical methods for gold and other precious metals in exploration studies. J appl Geochem 2008, 10(2A), 545-62.

Various analytical methods, ranging from the classical fire-assay methods to the most modern instrumental techniques such as inductively coupled plasma mass spectrometry (ICP-MS) for the estimation of gold and other precious metals in geological samples, have been utilized in gold exploration programmes in certain parts of Karnataka. These methods have been evaluated for their suitability to generate data rapidly for exploration purposes. Classical fire-assay methods are found to fail very often when very low concentrations of gold in rocks such as banded iron formations (BIFs) are analyzed. On the other hand, cyanidation procedure is found to give satisfactory results especially in BIF because of its ability to deal with larger amounts of samples (200g). Since most of the gold ores are inherently inhomogeneous, 25 gms of-250 mesh sample treated with aqua regia yielded reproducible results by ICP-MS. In certain cases, even 10g sample weights were found to be representative for gold analysis. The other advantages of ICP-MS are its ability to give highly reliable data very rapidly for other precious metals, namely, Ag, Pd and Pt. pathfinder elements such as As and Te and other trace elements such as rare earth elements (REE). The data on other elements provide a comprehensive outlook in geochemical prospecting studies and help to refine the strategies for exploration in the adjoining areas. A comparative study of the replicate analysis of International Geochemical Reference Samples form Canada, China and USA by different analytical approaches are presented. Due to their low detection limits and high sample throughput capabilities, the cyanidation method, aqua regia treatment, and aqua regia-bromine method of dissolution in combination with AAS and ICP-MS are found to be more suitable for the analysis of large number of samples needed for geochemical mapping programmes on a regional scale.

14 tables, 57 ref

005293   Bajpai R K;Narayan P K (Repository Programme Section, Nuclear Recycle Group, Bhabha Atomic Research Center, Trombay, Mumbai-400 085, Email: rkumar@apsara.barc.ernet.in) : Role of earth sciences in deep geological disposal of radioactive wastes. J appl Geochem 2008, 10(2A), 481-9.

Site selection for geological repository is carried out on the basis of extensive remote sensing based geological interpretation of large regions spanning over thousands of square kilometers exposing homogeneous rock mass. The site thus identified, is then subjected to detail geoscientific characterization in terms of geology, geophysics, geochemistry and rock mechanics to generate comprehensive database to assess response of host rock to complete waste disposal activity which will involve excavation, heat generating waste emplacement and backfilling with suitable material like crushed rock or clays. Efforts are also made to predict future evolution of such sites. This requires extensive studies on palaeoenvironment; palaeoclimate, and palaeo-seismicity. Probability of disruptive events like earthquakes, volcanoes, flooding and uplift are also estimated. For generation of information on in situ rock and groundwater conditions, underground laboratories are constructed in the depth range of 400-500m to conduct geological and geohydrological experiments. Besides site selection and characterization, development of glass and ceramic matrix for immobilization of waste forms an integral part of experiment petrology. For performance of such waste forms, a large number of geochemical studies are performed on this matrix to study mechanism of alteration, rates and products. The vitrified waste overpack will be emplaced in rocks with a layer of clay buffer around them. These clays will retard groundwater penetration towards waste and will also arrest release of radioactive elements from waste. These clays are mostly millions years old geological material found in sedimentary basins. Complete mineralogical and geochemical characterization of these materials forms an integral part of geological repository programme. Application of numerical simulation of repository processes is necessary to extrapolate results of short term laboratory based studies to such periods. The most commonly modeled processes include development of thermal field around disposed wastes, modification in in situ stresses, evolution of geohydrology and geochemical reactions at the interface of waste/buffer/rocks as function of time.

4 illus, 12 ref

005292   Bajpai R K;Narayan P K (Back end Technology Development Div, Atomic Energy Dep, Nuclear Recycl, Bhabha Atomic Research Center, Mumbai-400 085, Email: rkumar@apsara.barc.ernet.in ) : Sandstone uranium deposits of Meghalaya : natural analogues for radionuclide migration and backfill material in geological repository for high level radioactive waste disposal. J appl Geochem 2008, 10(2A), 475-80.

Sandstone uranium deposits serve as potential natural analogue to demonstrate safety offered by geological media against possible release of nuclear waste from their confinement and migration towards biosphere. In the study, available database on geochemical aspects of Domisiat uranium deposit of Meghalaya has been evaluated to highlight the behavior of radionuclides of concern over long term in a geological repository. Constituents like actinides (U and Th). fission products and RE elements are adequately retained in clays and organic matters associated with these sandstone deposits. Also highlights the possibility of utilization of lean ore discarded during mining and milling as backfill material in far field areas and optimizing near field buffers/backfills in a geological repository located in granitic rocks in depth range of 400-500 m.

11 ref

004190   Zakaulla S;Rajaraman H S;Dhurandhar A P; Timothy R;Umamaheswar K (Atomic Energy Dep, Atomic Minerals Directorate, Bangalore, Email: s_zakaulla@yahoo.com) : Petrology and geochemistry of Meso-Proterozoic arenaceous sediments of the Barapani Formation of Shillong Group in parts of Meghalaya and Assam. J Geol Soc India 2008, 71(5), 683-92.

In the Proterozoic Shillong Group, the Meso-Proterozoic arenaceous Barapani Formation, unconformably overlies the Paleo proterozoic Tyrsad Formation. Argillaceous quartz arenite, quartzite and quartz wacke are the constituents of Barapani Formation, in both Meghalaya plateau and Mikir Hills in Assam. Samples from both the domains contain same type of detrital grains. Monocrystalline quartz forms about 70 to 90% and feldspars and lithic fragments form minor part of the framework constituents. Sericite is the major mineral in matrix. Geochemical data (major and trace elements) of these arenites show overall similar elemental composition of all the samples from both Meghalaya plateau and Mikir Hills, Assam, indicating constancy of provenance. However, samples from the Mikir Hills as compared to that from Meghalaya Plateau show depletion in FeO(t), CaO, and MgO and enrichment in V, Cr, Co, Ni and Cu. Samples from both the Meghalaya plateau and Mikir Hills indicate a passive margin tectonic setting of sedimentation.

10 illus, 3 tables, 11 ref

004189   Srinivas Y;Muthuraj D;Chandrasekar N (Center for Geo-Technology, Manonmaniam Sundarnar University, Tirunelveli-627 012, Email: drysv@yahoo.co.in) : Resistivity studies to delineate structural features near Abhishekapatti, Tirunelveli, Tamil Nadu, India. J Indian Geophys Union 2008, 12(4), 157-63.

Geophysical survey using electrical resistivity method was carried out near Abhishekapatti, Tirunelveli district, Tamilnadu in order to delineate the possible structural features of the subsurface. A detailed survey was carried out using an indigenously made resistivity meter. Electrical resistivity profiling using Wenner configuration and vertical electrical sounding with Schlumberger configuration were carried out. The study area is covered of thin soil underlain by crystalline massive metamorphic rocks of high resistivity. The inferred resistivity structure from Wenner and Schlumberger method yield significant insight into the resistivity distribution of the area. Vertical and lateral extension of low resistivity features, resistivity pseudo section and apparent resistivity contour map indicates the existence of a contact zone approximately in east west direction.

5 illus, 14 ref

004188   Sharma B;Dinesh Kumar;Teotia S S (NO, Institute of Seismological Research, Sector-18, Gandhinagar-382 018, Email: babita_s@rediffmail.com) : Site amplification factors in Koyna region using coda waves. J Indian Geophys Union 2008, 12(4), 149-56.

Site amplification factors have been obtained at two sites of Koyna region using the reference site method. The coda waves of 37 local earthquakes have been used for this purpose. The site Warna (WRN) has been taken as reference site on the basis of local geology for the estimation of site amplification factors at Chikali (CKL) and Katwali (KTL). The coda decay curve has been prepared for the three sites in order to validate the spectral ratio method used here. The single back scattering model has been used to obtain the coda decay curve of the region. The coda decay curves have been found to be similar for all source-station pairs in Koyna region except at very low frequencies. The estimated site amplification values show the non-linear variation with frequency at all the sites considered. The amplification factors vary from 1.4 to 3.3 at CKL and 1.6 to 3.1 at KTL. The amplification factors at both the station increase with increase in frequency in the wide range 5 - 13 Hz. The station CKL shows the higher amplification factors as compared to KTL in this frequency range. This reflects the difference in the station site geology as the amplification factors decrease with in increase in geological age. The results presented here are the first order of estimation in this region.

3 illus, 3 tables, 39 ref

004187   Shankar R;Pandarinath K (Marine Geology Dep, Mangalore University, Mangalagangotri-574 100) : Mineral magnetic signature of the Early Holocene intense monsoon conditions recorded in sediments from the southwestern Indian continental margin. J Geol Soc India 2008, 71(5), 670-82.

Studied three sediment cores from the southwestern continental margin of India for their mineral magnetic properties like magnetic susceptibility (χ_IF), susceptibility of anhysteretic remanent magnetisation (χ_ARM), isothermal remanent magnetisation (IRM), saturation isothermal remanent magnetisation (SIRM) and inter-parametric ratios (χ_ARM/χ _lf and χ _ARM/SIRM), besides particle size characteristics. Demonstrates here that magnetic susceptibility and other mineral magnetic parameters can be used to demarcate the Early Holocene intense monsoon conditions: High values of χ_lf, χ>_(ARM), IRM_20mT, SIRM and χ _ARM/χ_IF and χ _ARM/SIRM in the core-bottom indicate the peak wet period ~ to 11 to 9 ka B.P. The values decrease rapidly at 8.38 ka B.P, in concert with a reduction in rainfall. Authors interpretation is strengthened by particle size data on a limited number of samples. Silt and sand contents are higher in the pre-8.38 ka B.P., high-susceptibility samples than in the post-8.38 ka B.P., low-susceptibility samples. The high values of concentration-dependent parameters and χ_ARM/χ_lf in the core-tops are probably due to an increase in rainfall during the past 100-400 years. Authors also used the mineral magnetic parameters to correlate the sediment cores.

8 illus, 2 tables, 41 ref

004186   Santhi S (Biological Science Dep, Institute of Advanced Study in Education, Saidapet, Chennai-600 015) : Distribution of five species of water striders (Heteroptera; Gerridae) in Erode area, Tamil Nadu. J Ecobiol 2008, 22(2), 123-8.

Distribution of five species of water striders (Tenagogonus (Limnometra) fluviorum Fabricius, Neogerris parvulus Stal, Aquarius adelaidis Dohrn, Limnogonous fossa rum fossa rum Fabricius and Limnogonous nitidus Mayr) (Heteroptera; Gerridae) found in seven taluks of Erode District, Tamil Nadu were studied. T. fluviorum was abundant in Erode District followed by L. nitidus. L. nitidus was wide, spread among the five species, as they occurred at 83 of the 150 sites and accounted for 24.1 percent, whereas T. fluviorum was present at 49 sites comprising the maximum of 27.9 percent. The species found in least density was L. fossarum (13%). All of these species never occurred together in any of the sites. It was observed that N. parvulus shows preference for lotic habitat, but T. f1uviorum, and A. adelaidis prefer lentic habitat. The remaining two species L. fossarum and L. nitidus exist in both lotic as well as lentic habitats. Alary dimorphism is exhibited by all the species.

2 illus, 2 tables, 20 ref

004185   Roy P J;Roy M K;Shome D;Abdullah Al Mahbub M; Roy D K;Saha S (Geology and Mining Dep, University of Rajshahi, Rajshahi-6205, Bangladesh) : Petrography of the Sylhet limestone formation, the Dauki river section, Gwainghat, northeastern Sylhet, Bangladesh. J Geol Soc India 2008, 71(5), 724-30.

Rock sequences of the Sylhet Limestone Formation, Dauki River section, Gwainghat, Sylhet were studied to identify their various petrological units, non-clastic minerals and fossil content. Limestones are of two varieties: crystalline in lower horizon and fossiliferous in upper horizon. The various petrological units identified in the non-clastic portion of the Sylhet Limestone Formation include micrites, dismicrites, intramicrites, pelmicrites, sparites, intrasparites, pelsparites, and oosparites. Calcite, dolomite and fossils with minor amount of clay, mica, chert, quartz, zircon, tourmaline, rutile, and opaque minerals constitute the limestones. Fossiliferous limestone consists of smaller and larger foraminiferal genera, such as Nummulites, Discocyclina, Alveolina, Operculina, Assilina etc with some Bryozoans and Brachiopod shells. The various petrological units might have deposited in shallow marine environment with non-reducing as well as reducing condition by tidal, winnowing and non-agitating currents. Algal growth aided the various units in formation.

3 illus, 19 ref

004184   Roy M K;Abdullah Al Mahbub M;Roy P J (Geology and Mining Dep, University of Rajshahi, Rajshahi-6205, Bangladesh, Email: mkr_c@yahoo.com) : Sedimentary facies and paleoenvironments of deposition of the Tipam Sandstone Formation, Chandraghona-Boraichari Area of the Sitapahar Hill Range, Chittagong Hill Tracts, Bangladesh. J Geol Soc India 2008, 71(5), 693-709.

Mio-Pliocene Tipam Sandstone Formation is well exposed in the Sitapahar Hill Range in Chittagong Hill Tracts, Bangladesh. Stratigraphically the rock sequence along the Chandraghona to Boraichari road-cut section consists of alteration of yellow to brownish yellow, very fine sandstone, siltstone, silty shale and gray to bluish gray shale with occasionally decomposed layers in varying proportion. Two facies associations recognized in the area are (a) medium to fine grained sandy-silty facies association, FAS and (b) the silt-clay facies association or heterolithic facies association, FAHL. The facies characteristics suggest that the deposition was restricted within estuary to tidal channels in FAS and very shallow water condition as well as mainly tidal flat to tidal marsh environment in FAHL. The dominantly bi-directional and bi-polar paleocurrent characteristics strongly support presence of tidal action in the Tipam Sandstone Formation in the study area.

7 illus, 4 tables, 42 ref

004183   Rahman M A;Rahman S M;Islam M R;Keramat M (Physics and Electronic Engineering Dep, University of Rajshahi, Rajshahi-6205, Bangladesh, Email: arifour_rahman@yahoo.com) : Geological constituents of mid Atlantic seismic oceanic crust with the application of attributes in seismic profile. J Geol Soc India 2008, 71(5), 717-23.

Geologic constituents of the mid Atlantic seismic profiles have been studied with attributes analysis to make a bridge in between geology and seismic. Attributes computation is justified for one test signal. Later the amplitude and frequency attributes have been estimated the mid Atlantic region seismic profiles. The image made in this work is found better than that of the raw seismic data. Amplitude attributes indicated reasonable stratified earth of the crust. The reflecting beds are well presented in the analyzed sections. The boundaries are characterized on the basis of basic wave propagation, as it is observed that the signal strength from the nearest reflecting bed is higher than that of distant bed. Estimated frequency attributes of the profiles are indicated the evidences that the oceanic crust are probably gabbros with little mixture of peridotite. The constituents are estimated on the basis of frequency distribution of each trace of the whole profiles. Analysis has suggested that gabbro and peridotite are the main geological constituents mixing up with different degrees with depths of the study area.

8 illus, 33 ref

004182   Pallavika;Kalyani V K;Chakraborty S K;Sinha A (Applied Mathematics Dep, B.I.T., Mesra, Ranchi-835 215, Email: vkkalyani@yahoo.com) : Finite difference modeling of SH-wave propagation in multilayered porous crust. J Indian Geophys Union 2008, 12(4), 165-72.

Deals with the propagation of SH-waves in a multilayered porous media with Weiskopf type anisotropy. Using Biot's theory of porous medium, the problem has been formulated. The finite difference method has been used here to model the wave propagation problem and also to analyze the effect of porosity and anisotropic factors on the phase and group velocities. Three-dimensional diagram has been developed to describe the displacement of the SH wave propagation as a function of two variables x and z. Also, the relation has been developed between the incremental displacement and the time, which is shown graphically. The convergence and stability criteria of the finite difference method has been established i) to minimize the exponential growing of the error; ii) to make the finite difference method stable; and iii) to decide the valid range of numerical values of the parameters.

9 illus, 20 ref

004181   Kulkarni K G;Borkar V D;Petare T J (Geology and Palaeontology Group, Agharkar Research Institute, G.G. Agarkar Raod, Pune-411 004, Email: kantimatik@yahoo.co.in) : Ichnofossils from the Fort Member (Middle Jurassic), Jaisalmer Formation, Rajasthan. J Geol Soc India 2008, 71(5), 731-8.

Ichnoassemblage from the Fort Member, Jaisalmer Formation, occurring in a hill north of the city of Jaisalmer is described. It comprises Arenicolites tenuis isp. nov., (?)Bichordites isp., Planolites isp., Rhizocorallium irregulare Mayer, Rhizocorallium jenense Zenker, Taenidium serpentinum Heer and Thalassinoides isp. Overall paucity of repichnia in an ichnoassemblage vis-…-vis noticeable dominance of domichnia and fodinichnia implies abundance of detrital nutrients. Host rocks yielding this ichnoassemblage are current bedded calcarenite showing fine shell hash along current beds and clayey limestones with presence of small, lenticular storm bed intercalations. They suggest near-shore, moderate- to strong-energy marine conditions rich in organic nutrients, supporting inferences drawn on the basis of trace fossils. The beds containing this ichnoassemblage are assigned ages ranging from Bathonian to Callovian, and hence considered here Middle Jurassic.

2 illus, 1 table, 38 ref

004180   Krishnaswamy V S (NO, , 409 South Lexington Avenue, White Plains, NY 10606, U.S.A., Email: ramsaranam@aol.com) : Geological environment of some ancient caves of India: their optimum utilization for speleological exploration and hydrogeological research. J Geol Soc India 2008, 71(5), 630-50.

Study of the geological features and the speleological origin of 80 "ancient" caves of India suggests their grouping under five different geological environments and five separate speleological processes. The cave environments are portrayed on a preliminary "Cave and Karst Map of Peninsular India and the Himalaya". A possible pattern of hydrogeological and hydrological research, utilizing the caves located in the carbonate rocks of the Kurnool and Palnad areas of the State of Andhra Pradesh, is outlined, in order to get an insight into the realm of surface water-ground-water interaction and to evaluate the extent of groundwater storage and release from karstic limestone formations. The recently described, volcanogenic karst features of the Deccan basalts of Western Maharashtra, interpreted to lie in a zone of lava flows covering an area of 1,20,000 sq km also includes the locations of all the existing rock-cut caves in Maharashtra that host ancient architectural monuments and works of art. The coincidence of the two features may either be accidental, or, may have a rational explanation. Additional field checking of the photogeologically interpreted lava-karst features in the cited special zone of Deccan basalts, in order to establish the open or filled nature of the lava karsts, may yield useful clues in this regard. The presence of sub-aerial pseudokarst, in the mantle of the boulder -talus of granite tors that cover the Closepet granites at Hampi in Karnataka and the recent finding of a 3-kilometre-long "river-cave" therein, suggest the need for additional hydrological and hydrogeological studies, for defining the extent of openness of the pseudokarst mantle and the ground-water storage potential of the pseudokarst around the proposed test-sites. These studies would need specially located river gauge-discharge sites to be established temporarily, in the two river basins and the use of ground-water data of existing open wells, in the belt of the Closepet granites extending from the Tungabhadra river valley of the Krishna river basin in the north, to the Arkavathi river valley of the Kaveri river basin in the south, located west of Bangalore. A programme of National Survey of the Cave Wealth of India is suggested, for which, the creation of a Specialist Division within the framework of the existing Federal and State geo-scientific organizations is warranted, along with the opportunities for specialized training in the mountaineering -type of skills needed for handling difficult cave exploration and mapping, both of which need a spirit of adventure for advancing scientific knowledge.

10 illus, 1 table, 28 ref

004179   Krishnakanta Singh A;Debala Devi L;Ibotombi Singh N (NO, Wadia Institute of Himalayan Geology, North East Unit, Itanagar-791 113, Email: kk_luwang@rediffmail.com) : Platinum group elements (PGE) and gold in the ultramafic rocks of Manipur ophiolitic complex, northeast India. J Geol Soc India 2008, 71(5), 739-43.

Platinum Group Elements (PGE) (Os, Ir, Ru, Rh, Pd, Pt) with Au and Ag content in ultramafic rocks (harzburgite, lherzolite, wehrlite, dunite and tectonite) from the northern part (Ukhrul area) of the Manipur Ophiolite Complex (MOC), Indo-Myanmar range has been discussed briefly. The ultramafic rocks shows higher concentration of Palladium-group PGE (PPGE) (Rh=4.4-6.6 ppb; Pd=336-458 ppb; Pt=14.6-36.4 ppb; Au=38.8-116.8 ppb) and Ag (94-145 ppb) than the Iridium-Group PGE (IPGE) (Os=2.4-5.8 ppb; Ir=3.2-4.8 ppb; Ru=5.2-7 ppb). They are characterized by overall enrichment of PGE concentration (ΣPGE=393.6-518.2 ppb) and high ratio of (Pt+Pd)/(Os+Ir+Ru) (24.18-35.23 ppb). The constancy of the ratios Ir/Os, Ru/Os, Ru/Ir suggests that these elements were in thermodynamic equilibrium during the crystallization. Cu/Pd ratios (1183-1473 ppb) in these rocks are lower than those in primitive mantles, probably suggests that the rocks contain cumulus sulphides. Preliminary studies indicate high concentration of PGE in the ultramafic rocks of MOC and further detail study is warranted to assess the economic feasibility of Platinum Group Elements and Gold.

2 illus, 1 table, 15 ref

004178   Jamir T;Gadgil A S;De U S (Environmental Science Dep, University of Pune, Pune-411 007, Email: tongdi@unipune.ernet.in) : Recent floods related natural hazards over west coast and northeast India. J Indian Geophys Union 2008, 12(4), 179-82.

Severity of the weather, which manifest in the form of floods and landslides on account of rainfall, has a substantial impact on life and properties. In view of these, an attempt is made in this paper to study the economic damage and human casualties associated with floods that occurred during the period 1971-2005 over two specific zones i.e. northeast and the west coast regions of India. For the study, data from Disastrous Weather Events, Weekly Weather Reports and "Weather in India" published by Indian Meteorology Department during the above mentioned period have been analyzed. The study reveals that flood frequencies and associated human casualties and economic losses have increased in the recent decade.

1 illus, 3 tables, 8 ref

004177   Chandra H;Sharma S;Das S R;Raghava Rao R (NO, Physical Research Lab, Navarangpura, Ahmedabad-380 009, Email: hchandra@prl.res.in) : Vertical velocity from HF doppler measurements over Ahmedabad. J Indian Geophys Union 2008, 12(4), 173-8.

HF Doppler radar operating at 2.5 MHz was developed and operated at Ahmedabad for a number of nights during 1986-87. The system made use of the existing ionosonde, C-4 model, as transmitter and a crystal controlled frequency synthesiser provided the RF excitation. Quadrature outputs of the phase coherent receiver were recorded both in analogue form on paper charts and in digital form at a sampling rate of 50 Hz. The velocity could be determined with a resolution of 1 m/s. Measurements show vertical velocity ranging between 0 and 25 m/s with a mean value of 9.2 m/s. A comparison with the vertical velocity obtained from the time variation of the minimum virtual height of F-layer, h'F, from a co-located ionosonde shows good agreement.

5 illus, 15 ref

003190   Venkateswara Sarma V (NO, , G 1, Ganpath Villa, 67, admavathy Nagar, Virugambakkam, Chennai-600 092, Email: sarmavv@yahoo.com) : Rice cultivation is not cause for climate change. Curr Sci 2008, 95(9), 1105-6.

4 ref

003189   Udaya Laxmi G;Himabindu D;Ramadass G (Center of Exploration Geophysics, Osmania Univ, Hyderabad-500 007, Email: udayalaxmi@yahoo.com) : Variation of physical properties of the granites of Hyderabad, Andhra Pradesh, India. Curr Sci 2008, 95(9), 1341-7.

Measured densities, susceptibilities and P-wave velocities of 569 samples from five categories of granites -biotite granite, pyroxene granite, medium-grained pink granite, coarse-grained pink granite and grey granite - collected from important geological outcrops of Hyderabad, Andhra Pradesh, India were taken in pairs and subjected to the two-sided Kolmogorov-Smirnov statistical test to determine whether the tonally/ geologically differentiated granites represent distinct categories in terms of the physical properties as well. It was found that while with respect to density a statistical difference was detected between the medium-grained pink granite and coarse-grained pink granite, as also between the coarse-grained pink granite and pyroxene/biotite granite, no such difference was found with respect to magnetic susceptibility and jP-wave velocity. These findings are useful for litho-mapping and structural evaluation, apart from contributing to the physical property database of the granite rocks of Hyderabad region.

6 illus, 2 tables, 30 ref

003188   Trivedi A;Chauhan M S (Geology Dep, Lucknow Univ, Lucknow-226 007, Email: atrivedee@gmail.com) : Pollen proxy records of holocene vegetation and climate change from Mansar lake, Jammu region, India. Curr Sci 2008, 95(9), 1347-54.

Pollen analysis of a 30 m deep sediment core from Man-sar Lake has revealed that around 9000-8000 yrs BP, the mixed chirpine-oak forests dominated by Pinus cf. roxburghii (chirpine) existed in the Jammu region under a cool and dry climate. Later, they were succeeded by mixed oak-chirpine forests between 8000 and 7000 yrs BP with the expansion of oak (Quercus cf. in-cana) and other broad-leaved taxa in response to initiation of a warm and humid climate. Between 7000 and 3000 yrs BP, the cool and dry climate prevailed again as inferred by the reduction in broad-leaved taxa and a simultaneous improvement in the conifers, especially Pinus cf. roxburghii. However, a brief spell of pluvial activity is witnessed between 5500 and 4250 yrs BP, as envisaged by the presence of sandy deposits. Around 3000 to 750 yrs BP, expansion of oak and most of the broad-leaved taxa suggests the prevalence of a warm and more humid climate. From 750 yrs BP to the Present the climate deteriorated, as reflected by the replacement of mixed oak-chirpine forests by mixed chirpine-oak forests in the region. There has been an acceleration of human activities during the last millennium as indicated by the record of culture pollen taxa.

3 illus, 20 ref