011193   Mohapatra B K;Mishra P P;Singh P P;Paul A K; Rajeev (NO, Regional Res Lab, Bhubaneswar, Email: bkmohapatra@yahoo.com ) : Co-rich lithiophorite in manganese ores of the Bonai-Keonjhar belt, Orissa. J Geol Soc India 2005, 66(4), 407-81.

Co-rich Lithiophorite is reported for the first time from low-grade Mn ores of the Bonai-Keonjhar belt (Jamda-Koira valley), Orissa. It occurs in two distinct litho-host associations; (i) lateritic zone capping Mn-ore horizon and (ii) shear zone-controlled siliceous manganese ore. It mostly appears as thinly banded and as vug-filled linings, in close association with cryptomelane. It occurs as micron-sized acicular to pea-shaped crystallites in the first litho-association and as coarse, radiating crystals showing zig-saw pattern arrangement in the second association. Co content is low (CoO: 0.14-0.8%) in the fine-grained variety whereas in the coarse-grained variety it ranges up to 2% (CoO: 0.14-2.00%). Appreciable quantity of Ni (NiO: 0.15-1.5%) is observed along with Co only in coarse-grained variety. The mechanism of Co-entry into the two varieties of supergene lithiophorite through adsorption has been discussed. Report of Co in terrestrial Mn-ore has opened up new potential in this part of Orissa.

^ssc2 illus, 2 tables, 2 ref

011192   Mishra S K;Mohanty J K (NO, Regional Res Lab, Bbhubaneswar-751 013, Email: jkmohanty@rrlbhu.res.in) : Importance of petrographic study of non-coking coals from Talcher coal field, Orissa in coal utilisation. J Geol Soc India 2005, 66(4), 475-85.

Provides general information on petrographic findings of coal from different seams presently exposed in Talcher coalfield in terms of lithotype, maceral, microlithotype, mineral matter and rank (vitrinite reflectance). Importance of lithotype, mineral matter and oxidation characteristics of coals with respect to coal preparation/beneficiation and maceral/microlithotypes in combustion has been discussed in detail.

8 illus, 8 tables, 49 ref

011191   Mathankar G;Agrawal G D (NO, Mahatma Gandhi Chitrakoot Gramodaya Vishwavidyalay, Chitrakoot, Satna-485 331) : Comparison of atmospheric turbulence at satna and nimbahera in the winter month of december. Indian J envir Prot 2005, 25(2), 109-18.

Winter season micrometeorologicai data characterised by eight days of the peak winter month of December, for two distant places [Satna (M.P.) and Nimbahera (Rajasthan)] has been examined. Four schemes for classifying the atmospheric turbulence (Temperature gradient, Turner's table, Richardson number and σ_θ) are considered. Wind direction, wind speed patterns are also interpreted. Both the places are found to more or less possess similar type and level of turbulence close to ground level throughout the day and night during the analysed period.

2 illus, 5 tables, 7 ref

011190   Mallikharjuna Rao J;Suresh Raj T;Rama Rao P (NO, Natn Geophys Res Inst, Hyderabad-500 007) : Petrology and geochemistry of Puliyampatti and Pollachi Udumalpet granites of southern granulite terrain and their tectonic implications. J appl Geochem 2005, 7(2), 256-70.

Proterozoic to younger granites were emplaced in the Southern Granulite Terrain, particularly to the north and south of and within the Moyar-Bhavani (M-B) and Palghat-Cauvery (P-C) shear zones. P-T studies indicate that the northern and the southern parts of M-B and P-C shear zones have metamorphosed to similar P-T (600°-700°C and 6-7 kb) while the M-B and P-C shear zones show a higher P-T metamorphic regime (740°-950°C and 8.2-10 kb). The Proterozoic granites are mostly tonalitic in composition and are similar to the granite-gneisses of the northern amphibolite grade terrain and are restricted to the north of P-C lineament while the younger Neoproterozoic granites are leucocratic to light pink and occur south of and within the M-B and P-C shear zones. Geochemical signatures of the Puliyampatti granites and Pollachi-Udumalpet granites indicate their I-type nature and volcanic arc tectonic setting of emplacement. The Pollachi-Udumalpet granites range in composition from alkali granite, alkali feldspar syenite to granite while the Puliyampatti granites are simple granites and are more enriched in SiO2 (70-73, av, 72.04%), Na₂O (4-7.7, av. 6.6%), Al₂O₃ (15-17, av. 15.83%) and depleted in total REE (8.2-30.8, av. 18.92 ppm), U (<60> 1, av. 0.3 ppm), Th (0.1-8.5, av. 1.17 ppm), Ba (210-1800, av. 447 ppm), Rb (6-85, av. 27 ppm), Y (1-3, av. 2 ppm) and Nb (1-7, av. 2.3 ppm), compared to the Pollachi-Udumalpet granites and show mostly metaluminous character. The latter, on the other hand, are enriched in high field strength elements (HFSE) and have higher concentrations of REE, Ba (297-5542, av. 2030 ppm), U (0.2-6, av. 0.6 ppm), Th (0.4-123.8, av. 36 ppm), Zr (11-286, av. 119 ppm), Nb (1-26, av. 9 ppm), Rb (16-151, av. 95 ppm), Sr(66-1955, av. 668 ppm) and are of peraluminous character. The REE fractionation trends vary considerably within these granites and exhibit both positive and negative Eu-anomalies (Eu/Eu* =1.1-3.2 in Puliyampatti granites and 0.2-7.1 in Pollachi-Udumalpet granites). The entire Southern Peninsular India, south of shear has undergone major extensional tectonics and deformation during Pan-African orogeny resulting in large scale crustal anataxis and emplacement of several granites. Such a widespread granitic emplacement has also been documented in Madagascar, Sri Lanka and Antarctica of East Gondwanaland.

9 illus, 2 tables, 25 ref

011189   Majumdar R K;Pal S K (Dep of Geol Sci, Jadavpur Univ, Kolkata-700 032, Email: ranjit_mazumdar2000@yahoo.co.in) : Geoelectric and borehole lithology studies for groundwater investigation in alluvial aquifers of Munger district, Bihar. J Geol Soc India 2005, 66(4), 463-74.

Geoelectric studies and borehole logs of Older and Younger Alluvium adjacent to Chhotanagpur plateau fringe area in the district of Munger, Bihar, indicate the presence of clay unit at many places near the surface and occasionally at depths. The clay unit does not occur as a continuous layer. This indicates that the aquifer, in general, is under unconfined condition. Study of borehole logs and results obtained from interpretation of vertical electrical soundings are useful to find out potential groundwater bearing zones. A panel diagram has been prepared to understand the nature and disposition of the aquifer(s) and thereby hydrogeological framework prevailing in the area. Based on comparison of interpreted sounding data and available borehole log information, resistivities of different lithological formations have also been determined. Layer parameters obtained from vertical electrical sounding (VES) studies corroborate the lithologs of the area. Estimation of aquifer hydraulic properties using surface electrical resistivity method has also been attempted. For such estimation, hydraulic conductivities and transmissivities determined from pumping tests have been correlated with resistivities obtained from electrical soundings. Empirical relations between aquifer electrical resistivity and aquifer hydraulic conductivity, aquifer resistivity and specific capacity and aquifer transverse resistance and transmissivity have been developed. All the relations thus developed can be used for estimation of hydraulic properties of the aquifer(s)of the study area. Using geoelectric data and applying Archie's equation, an estimation of the bulk porosity of the aquifer is done and it ranges from 0.295 to 0.477.

5 illus, 4 tables, 35 ref

011188   Madhusudan Rao B;Jettaiah P (Dep of Geophysics, Osmania Univ, Hyderabad-500 007) : Acoustic non-linearity parameter of certain alloys of rare-earth elements. Bull pure appl Sci-Sect F 2004, 23(1-2), 59-64.

The Acoustic non-linearity parameter for three different longitudinal propagation direction namely <100>. <110> and <111> of 3 rare earth elements like Ta - W (at five different percentage of W). Nb - Mo (at six different percentage of Mo) and Ti - V (at four different percentage of V near room temperatures are calculated with available data using SOEC. It is observed that the values of all three rare-earth elements with different percentage of concentrations are found to increase along <100>. and . The results are presented citing their applications.

4 table, 6 ref

011187   Kuniyal J C;Momin G A;Rao P S P;Safai P D; Tiwari S;Ali K;Gajananda K (G.B. Pant Inst of Himalayan Envir and Dev, , Himachal Unit, Mohal-Kullu-175 126, Email: kuniyaljc@yahoo.com) : Aerosols behaviour in sensitive areas of the northwestern Himalaya, A case of Kullu-Manali tourist complex, India. Indian J Radio Space Phys 2005, 34(5), 332-40.

Total suspended particulate (TSP) matter on fortnightly basis throughout the year and mass size distribution of aerosols as well as ultrafine aerosols on weekly basis in the months of May and June were monitored during 1996-2003 at different altitudinal locations of the Kullu-Manali tourist complex in the northwestern Himalaya. Concentration of TSP ranged from 35.8 (August 1996) to 207.3 μg m^-3 (June 2003) at Mohal [1150 m from average sea level (ASL)] and from 31.7 (July 2003) to 239 μg m^-3 (April 2001) at Manali (2050 m ASL). The mass size distribution of aerosols showed a bimodal distribution having one peak in the coarse size range (3.3-9 μm dia) and the other in the fine size range (0.08-2.1 μm dia) at both the locations. Ultrafine aerosol (UA) (0.001-0.1 μm radius) concentrations were found to be highest at the lowest experimental altitude site (Mohal) and vice versa. The diurnal variation of UA concentration for three years showed that the concentration ranges from 2640 (at 0500 hrs LT) to 5160 Number (N) cm^-3 (at 1300 hrs LT) at Mohal and from 400 (at 0400 hrs LT) to 2190 N cm^-3 (at 1300 hrs LT) at Kothi. On an average, TSP crossed its permissible limit set by National Ambient Air Quality Standard (NAAQS) level in the sensitive areas such as Kullu-Manali hill spots. Bimodal nature of mass size distribution indicates two important sources contributing in total aerosols-the fine mode, primarily due to anthropogenic activities and the coarse mode aerosols, mainly due to natural sources. Large number of concentration of ultrafine particles indicates the presence of air pollutants more at low altitudes as compared to high altitudes.

5 illus, 1 table, 31 ref

011186   Khan K F;Israil S H (Dep of Geol, A M U, Aligarh-202 002, Email: farahimkhan@hotmail.com) : Geochemistry and depositional environment of Mussoorie phosphorite deposits, district Dehradun, Uttaranchal, India. J appl Geochem 2005, 7(2), 227-47.

The Mussoorie phosphorite deposits are restricted to the basal chert member (carbonaceous shale-chert-limestone) of the Lower Tal Group of Lower Cambrian. It is mined in the Durmala and Maldeota blocks. The phosphorites are grouped as granular, lenticular, bedded and bedded massive. Petromineralogical studies show that phosphate minerals (cellophane) make-up 45% of the mode of Maldeota deposit. Calcite (28.3%), dolomite (1.2%), chert (7.9%), pyrite (5.6%), sericite-clay (3.4%) and limonite (1.2%) are other minerals. Phosphorite minerals are found in the form of pellets, ovules, nodules and oolites, and show replacement with carbonate minerals. Major and trace elements in phosphorites (40) and the associated limestone (4), chert (6) and shale (9) samples from the chert member of the Lower Tal Group from the mining area of Maldeota and Durmala blocks were determined. The phosphorite of Durmala block is relatively more enriched in P₂O₅ (29%) than that of Maldeota (23%). This is due to greater admixture of chert (SiO₂), clay minerals (Al₂O₃) and pyrite (FeO) in Maldeota than Durmala samples. Trace element geochemistry reveals that the phosphorites are enriched in Ba, Cu, V, Cr, Ni, and Sr, and depleted in Li, Cd, Co and Rb. The variable concentration of trace elements in the phosphorites has been influenced by various physico-chemical processes involved during weathering and leaching of the source rocks and biogenic contribution to the basin. Distribution of majority of the trace elements was mainly influenced by the principal adsorbents like the phosphate minerals and some organic matter, in addition to clay, iron oxides and silicate minerals. It is inferred from the presence of pyrite that the deposition of phosphate might have occurred in the euxinic shallow marine environment. The deposition is controlled by biogenic factors such as marine upwelling leading to excess charge of phosphate in certain zones of phosphogenic basin and lithologic facies variations. Chemical factors such as negative Eh, pH with around 7.8 and relative proportions of CaO/MgO are other factors, which influenced the deposition of phosphates.

8 illus, 10 tables, 12 ref

011185   Kataki T;Khound D J (Keshav Dev Malaviya Project Dep Appl Geol, Dibrugarh Univ, Dibrugarh, Assam, Email: tarakeswark@yahoo.co.in) : Clay minerals and their burial diagenesis in the eocene-palaeocene sediments of part of upper Assam basin. J appl Geochem 2005, 7(2), 207-17.

The Eocene formations- Langpar, Therria-Lakadong, Sylhet and Kopili-emerge as important hydrocarbon prospects of a part of Upper Assam Shelf. Oil India Ltd. has drilled number of wells for exploration and exploitation on these prospects, but many wells were found to be unproductive. Study pertains to clay mineralogy of deep drilling samples from two unproductive- Khowang and Rajali-wells. Kaolinite and illite are pervasive in the Eocene sequence of Khowang well whereas illite and chlorite are found in the Rajali well. Illite - smectite mixed layer is found only in the top of the Sylhet Limestone Formation of the Khowang well. Dickite presence in Khowang well is detected in the Therria- Lakadong formation by the infrared and SEM study. The vertical distribution trend of relative amounts of clay minerals of the Khowang well indicates that the illite, in particular, decreases and kaolinite increases in the Lakadong-Therria Formation. However, in the Rajali well illite, in general, increases in while chlorite decreases with depth. The sharpness ratio of illite of both the wells is not significantly high and shows an increase in the Therria- Lakadong formation. The presence of dickite in the Therria-Lakadong formation of Khowang well indicates good permeability of that formation. However, the occurrence of kaolinite in the deeper depth of this well affects the porosity and permeability.

4 illus, 4 tables, 16 ref

011184   Joseph P V;Simon A (Dep of Atmospheric Sci, Cochin Univ of Sci and Technol, Fine Arts Avenue, Cochin-682 016) : Weakening trend of the southwest monsoon current through peninsular India from 1950 to the present. Curr Sci 2005, 89(4), 687-94.

The southwest monsoon current in the form of a cross-equatorial low level Jetstream (LLJ) with its core at an altitude of about 1.5 km and core wind speeds of 80-100 km/h is a conduit carrying moisture generated over south Indian Ocean and the Arabian Sea that supports the June to September monsoon rainfall in India. During spells of active (strong) monsoon, the core of the LLJ passes through peninsular India between latitudes 12.5 and 17.5 N. In break (weak) monsoon spells, LLJ bypasses India and flows to its south through the latitude belt 2.5 to 7.5 N. The mean June to September monsoon flow through India from surface to 1.5 km altitude between latitudes 12.5 and 17.5 N, had a significant decreasing trend and that between 2.5 and 7.5 N a significant increasing trend during the recent half century, i.e. 1950 to the present. The duration of break (weak) monsoon spells in a monsoon season has increased by about 30% during this period. These changes have resulted in the number of days during the monsoon season 1 June to 30 September with daily average rainfall less than 8 mm/day increasing and days with rainfall more than 12 mm/day decreasing through 45.4% and 78.1% respectively, during the last 53 years. These are alarming findings for a country whose food production and economy depend heavily on monsoon rainfall.

10 illus, 1 table, 22 ref

011183   Jeelani G (Dep of Geol & Geophysics, Univ of Kashmir, Srinagar-190 006, Email: jkhanday @ yahoo.co.in) : Chemical quality of the spring waters of Anantnag, Kashmir. J Geol Soc India 2005, 66(4), 453-62.

Among the various springs of Kashmir valley, 40 representative springs of Anantnag District were selected for a baseline study to assess the physico-chemical characteristics and suitability of spring water for drinking purposes. Four types of waters that were identified reflect the interaction of water under different lithological conditions. The observed values of major cations (Ca⁺⁺, Mg⁺⁺, Na⁺ & K⁺) and anions (HCO₃^-, SO₄^-, Cl^-, NO₃^- & F^-) are within the WHO standards, hence the waters are potable and good for domestic purposes. The four hydrochemical facies identified are CaHCO₃, MgHCO₃, and NaHCO₃ and hybrid type. The calculated PCO₂ values reflect the dynamic nature of the hydrologic system to which the springs belong. The saturation index values with respect to calcite, dolomite and gypsum have also been calculated.

5 illus, 3 tables, 10 ref

011182   Hidalgo-Gonzalez R M;Alvarez-Borrego S; Fuentesy-aco C;Platt T (Dep of Ecology, Div of Oceanology, CICESE, Km. 107 Carretera Tijuana-Ensenada, Ensenada, Baja California, Mexico, Email: alvarezb@cicese.mx) : Satellite-derived total and new phytoplankton production in the Gulf of Mexico. Indian J Mar Sci 2005, 34(4), 408-17.

Integrated total (P_Tint) and new production (P_newint) (gC m^-2 d^-1) were calculated for the Gulf of Mexico with semi-anatytical models from the literature, using chlorophyll a concentrations (Chl_sat) and the vertical attenuation coefficients of light (K₄₉₀) from monthly composites of the satellite sensor SeaWIFS (1997-2004). The phytoplankton biomass vertical distribution associated with Chl_sal, and the vertical distribution of the f-ratio [f_{(z) = Pnew(z)/PT(z)], were deduced from historic oceanographic data. Based on bathimetry, surface T øC, Chl and nutrients, the Gulf was partitioned into three regions: Yucatan, Deep-waters, and Mississippi. The year was divided into two periods for the Deep-waters region, "cool" and "warm." The whole year was treated as a single period for the Yucatan and Mississippi regions. Average values for PTint had a significant seasonal variation for the Deep-waters region (0.37-0.44 and 0.22-0.24 gC m^-2 d^-1, for the "cool" and "warm" periods, respectively), and similarly for Pnewint (0.023-0.026 and 0.013-0.014 gC m^-2 d^-1). Ranges for the average PTint values were 1.18 - 1.22, and 1.60 - 1.68 gC m^-2 d^-1, for the Yucatan and Mississippi regions, respectively. Ranges for Pnewint were 0.97 - 1.05, and 1.38 - 1.44 gC m^-2 d^-1. The limited data, do not show a significant interannual PTint and Pnewint variability in any region of the Gulf. Longer satellite time series for more complete future work may lead to the description of significant interannual primary production variability in the Gulf.}

3 illus, 3 tables, 50 ref

011181   Fuentes-Yaco C;Devred E;Sathyendranath S; Platt T;Payzant L;Caverhill C;Porter C;Maass H;White I I I G N (Dep of Oceanography, Dalhousie Univ, Halifax, NS, B3H 4J1, Canada) : Comparison of in situ and remotely-sensed (SeaWiFS) chlorophyll-a in the Northwest Atlantic. Indian J Mar Sci 2005, 34(4), 341-55.

Field measurements of phytoplankton pigment (chlorophyll-a) from the Northwest Atlantic are compared with concurrent pigment concentrations derived from SeaWiFS data using NASA/SeaDAS algorithms known as Ocean Chlorophyll 2 (OC2) and OC4 (versions 4.1 and 4.3). The results showed broad agreement but estimates using the NASA algorithms tended to show uncertainties, with lower than in situ values at concentrations greater than 1 mg chl-a m^-3. Regionally -, and seasonally-, adapted empirical corrections are developed in an attempt to reduce the bias. The magnitude of errors was quantified using linear regression. Further progress require application of a theoretical regional ocean-colour model.

11 illus, 4 tables, 44 ref

011180   Dwivedi R M;Solanki H U;Nayak S R;Gulati D; Somvanshi V S (NO, Space Applics Cent, Ahmedabad-380 015, Email: rmdwivedi@rediffmail.com) : Exploration of fishery resources through integration of ocean colour with sea surface temperature: Indian experience. Indian J Mar Sci 2005, 34(4), 430-40.

Exploration of fishery resources using remote sensing technique is based on the principle of identification of feeding grounds where fish tend to accumulate. It has been proven that thermal or colour gradients revealed by oceanic fronts indicate sites of high biological productivity. Some constraints in using SST (sea surface temperature) gradients for locating fish in the Indian waters were experienced such as the narrow range of SST and difficulty in detecting gradients, particularly in summer. Two approaches were developed and validated in the coastal waters of the west coast of India. In the first approach, SST contours (using NOAA AVHRR) were overlaid on chlorophyll image (from IRS P4 OCM) of corresponding date. This enabled identification of common frontal structures from the composite product. These sites were selected as priority fishing zones for the trial forecasts. Besides, ocean colour images were found to provide information on additional productive areas not found from SST images alone and hence, a second approach made exclusive use of patterns of ocean colour. Merits of ocean colour arose from penetration of visible radiation below surface up to one attenuation depth and from the frequent repeat cycle of the satellite data. The improvements with use of ocean colour include capability of prediction of oceanic features, exploitation of knowledge of the history of the features, identification of biological fronts in the deep sea waters etc. Also, such features as non-toxic winter blooms and internal waves were identified in the deep waters of the Northern Arabian Sea using chlorophyll images and the response of fish to these features was studied. The paper highlights how ocean colour improves the ability to locate areas of high abundance of fish. Because the time taken in information extraction from satellite data is a critical factor, on-line reception of OCM and AVHRR data was arranged. Fishery forecasts were generated using the integrated approach within 24 hours of satellite over pass, and disseminated to collaborating agencies for follow up fishing operation. The validation experiment for the forecasts was carried out for three years covering different seasons during 1999-2001. It was found that the forecasts were superior in terms of rate of success and magnitude of fish catch. Summary of feedback received indicated 70-90 % success rate (reliability) of the forecasts and 70-200 % increase in catch. In comparison with this, earlier SST-based approaches for the forecast yielded 50 % success rate and 40-50 % increase in catch. The integrated approach is currently being used to generate nation-wide fishery forecasts. In addition to this, cost-benefit analysis for the satellite fishery forecasts was also attempted. It was observed that the benefit: cost ratio increased from 1.27 to 2.12 for bottom trawling and 1.3 to 2.14 for gillnet fishing with the use of satelhte forecasts.

6 illus, 8 tables, 15 ref

011179   Dinesh A C;Maran N;Jayaprakash C;Venkateswara Rao C (Geol Surv of India, Mar Wing, Mangalore-575 001, Email: acdinesh@rediffmail.com) : MgdMAP-A friendly software for marine geochemical database management and plotting. J appl Geochem 2005, 7(2), 166-74.

Database of sample description as well as its geochemical, grain size and heavy mineral details are useful in the study of marine sediments. Retrieving desired data-set from the database and plotting them on a map manually is a time consuming process. GIS softwares are very much capable of doing this. A software (MgdMAP) is developed in Visual Basic, which enables even untrained user to create and edit the data and retrieve the desired data-set by giving simple/ complex queries and also to plot the data on a Mercator projected map. Four tables are designed in MS Access - a) Sample details b) Chemical details c) Grain size details and d) Heavy Mineral details. The user can directly feed the data by opening the respective table in MgdMAP. After creation of the database, user can connect the Access file with the software and can link the four tables in five different ways. After linking the tables, the user can send simple or complex queries to retrieve the data of the combined table. The query result can be plotted either on selected NHO chart, or on any part of India's coast map projected on Mercator generated in this software.

13 illus, 3 ref

011178   Dhana Raju R;Ravi G S;Shivkumar K;Reddy L S R;Rohatgi S (Dept. of Appl Geochemistry, Osmania Univ, Hyderabad-500 007, Email: rdhanaraju@yahoo.co.in) : WDXRFS method for quantification of heavy minerals in sand samples. J Geol Soc India 2005, 66(4), 401-06.

Estimation of industrial and strategic heavy minerals (HMs) in sands, viz., ilmenite, rutile, garnet, sillimanite, zircon and monazite, is usually carried out by Microscopic Grain-Counting technique on heavy liquid- and magnetically-separated fractions. This method is slow, laborious, time-consuming, costly, toxic and causes eye-strain. Its precision and accuracy depend on microscope-operator's skills in mineral identification and preparation, by micro-splitting of representative portions of fractions for analysis. Proposes a WDXRFS-based relatively simple, rapid, low-cost, non-toxic, eye strain-free and precise method. This involves: (a) magnetic separation of a sand sample into 3 sub-samples that are magnetic at 0.4 and 1.2 A and non-magnetic at 1.2 A; (b) WDXRFS analysis of these for the oxides and elements in the formulae of HMs; and (c) computation of the contents of HMs, assuming their stoichiometric composition. The contents of HMs in sand samples, determined by this method, are in general agreement with that from MGC method on natural sand samples and prepared samples, with an overall error of <60>20% and coefficient of correlation (r) of -0.98. Furthermore, our method gives additional information on end-member composition of garnet, Th-content of monazite and proportion of ortho- to clino- in pyroxenes.

2 illus, 2 tables, 2 ref

011177   Devred E;Fuentes-Yaco C;Sathyendranath S; Caverhill C;Maass H;Stuart V;Platt T;White G (Dep of Oceanography, Dalhousie Univ, Halifax, Nova Scotia, Canada B3H 4J1, Canada) : A semi-analytic seasonal algorithm to retrieve chlorophyll-a concentration in the Northwest Atlantic Ocean from SeaWiFS data. Indian J Mar Sci 2005, 34(4), 356-67.

In a companion paper it was demonstrated that the SeaWiFS OC4 algorithm, applied to the Northwest Atlantic, resulted in a systematic bias in the retrieved chlorophyll-a concentration. Their comparison of satellite-derived chlorophyll-o values with matching in situ observations showed that the OC4 algorithm as implemented in the NASA SeaDAS software package, overestimated chlorophyll-a in waters with low pigment concentration and underestimated chlorophyll-a for high pigment concentrations. An explanation for the observed bias, using a semi-analytic model of ocean colour modified to account for seasonal and regional variations in the spectral absorption properties of phytoplankton, dissolved matter (yellow substances) and detritus hsd been sought. The model is also extended into the near infrared region to evaluate the possible impact on the atmospheric correction algorithm. The results indicate that much of the bias can be explained by local variations in the inherent optical properties of particulate and dissolved matter present in the region. The algorithm based on the semi-analytical model eliminates practically all the bias (inaccuracy) in the retrieved chlorophyll-a concentrations, but does not improve the precision of retrieval.

6 illus, 5 tables, 46 ref

011176   Devendraa Siingh;Shubha Singh;Singh R P (NO, Indian Inst of Trop Meteorology, Pune-411 008) : Study of wave particle interaction in the disturbed magnetosphere. Indian J Radio Space Phys 2005, 34(5), 305-13.

Doppler-shifted cyclotron resonance interaction between whistler mode wave and counter streaming energetic electrons has been invoked to explain whistler triggered emissions recorded at low latitude station Varanasi {Geomagnetic latitude 14° 55', L= 1.07) during moderate magnetic storm activity (ΣK_P= 28^-, K_P index varies from 4^- to 4⁺ during the observation period) on 28 Feb. 1993. The mechanism of generation of triggered emissions is briefly discussed. Parallel resonance energy of participating electrons under normal and disturbed magnetospheric conditions have been evaluated, which is found to decrease with increase in L-value and wave frequency. Applying a simplified approach the interaction length, wave magnetic field and transverse resonant current, which are found to increase during the disturbed magnetospheric conditions have been estimated. However, the number of energetic electrons participating in resonance process under normal and disturbed magnetosphere remains approximately the same.

4 illus, 2 tables, 38 ref

011175   Desa E;Suresh T;Matondkar S G P;Desa E;Goes J;Mascarenhas A;Parab S G;Shaikh N;Fernandes C E G (NO, Natn Inst of Oceanography, Dona Paula, Goa-403 004, Email: elgar@darya.nio-org) : Detection of Trichodesmium bloom patches along the eastern Arabian sea by IRS-P4/OCM ocean color sensor and by in-situ measurements. Indian J Mar Sci 2005, 34(4), 374-86.

Detection of blooms of the marine cyanobacterium Trichodesmium from space has been studied using high resolution ocean color imagery in the visible wavebands of the OCM monitor (Ocean Color Monitor) on the IRS-P4 satellite platform. The standard detection protocol developed by Subramaniam et al., has been used. Localized bands of Trichodesmium were detected in OCM imageries of 16th,18th, 20th and 22nd March 2002 in decreasing numbers with time. The patches were aligned approximately parallel to the shoreline, and distributed over the shallow waters off the west coast of India. An analogous search of Trichodesmium bloom patches for these days using available SeaWiFS sensor (Sea Viewing Wide field of View Sensor) revealed features of reduced spatial resolution compared to that observed by the higher resolution OCM sensor, and at locations further offshore. In a field study during 19th to 22nd March 2002, at encountered Trichodesmium patches (<126> 90 km ) off the coast of Goa. Microscopic analysis confirmed that these patches belonged to the Trichodesmium erythraeum. These field patches were further offshore from the positions occupied by the near-shore patches seen in the OCM imageries during 18th to 22nd March 2002. Radiometric measurements made in the cruise-detected patches show water leaving radiances averaging - 1 μW/cm²nm, below the detection threshold of the satellite detection scheme. It is clear that further efforts are needed to improve the detection range of protocols so as to detect the presence of less reflective Trichodesmium patches of the type encountered during the cruise.

9 illus, 4 tables, 12 ref

011174   Datta T;Bhattacharya A;Bhattacharya R;Das R; De S;Bhattacharya A B (Dep of Phys, Kalyani Univ, Kalyani-741 235) : Sprites and elves-associated sferics produced by quasi-electrostatic thundercloud fields. Indian J Radio Space Phys 2005, 34(6), 387-98.

Investigations on sprites and elves glow and a comparison of the observational work obtained at various locations by different workers are reported. As the characteristic of these extraordinary phenomena is not yet well understood, an interpretation of the results is attempted from both experimental and theoretical points of view. The paper critically considers the latitudinal variations of lightning characteristics, as lightning flashes have a reported good relationship with the concerned unusual sprites and elves glow. It also discusses temporal variations of electron density, which is highly relevant as the extraordinary glow experienced between the cloud tops and the ionosphere. Subsequently, the sprites and elves associated sferics data in conjunction with electric and magnetic fields have been studied and the role of quasi-electrostatic thundercloud fields have been critically examined to focus this mysterious mesospheric glow.

9 illus, 1 table, 73 ref

011173   Chawthe S D (NO, FWWA HQ, Santacruz, Mumbai-400 055) : Rainfall intensities and 26/7 floods in Mumbai. J Indian Wat Wks Ass 2005, 37(3), 217,19.

2 ref

011172   Chauhan P;Nagamani P V;Nayak S (Mar and Wat Resour Grp, Space Applics Cent, Ahmedabad-380 015, Email: prakash@sac.isro.org) : Artificial neural networks (ANN) based algorithms for chlorophyll estimation in the Arabian Sea. Indian J Mar Sci 2005, 34(4), 368-73.

In-situ bio-optical measurements were collected during six ship campaigns in the north eastern Arabian Sea using SeaWiFS Multi-channel Profiling Radiometer (SPMR). An artificial neural network (ANN) based algorithms were constructed to estimate oceanic chlorophyll concentration using in-situ data. The different ANNs were obtained by systematic variations of architecture of input and hidden layer nodes for the Arabian Sea training data set. The performance of individual ANN-based pigment estimation algorithm was evaluated by applying it to the remote sensing reflectance data contained in validation data set. The performance of the most successful ANN was compared with commonly used empirical pigment algorithms. Compared to e.g. the SeaWiFS algorithms Ocean Chlorophyll-2 (OC2) and Ocean Chlorophyll-4 (OC4), the square of the correlation coefficient r² is increased from 0.69 for OC4, respectively 0.70 for OC2 to 0.96 for ANN algorithm. The RMS error of the estimated log-transformed pigment concentration dropped from 0.47 for OC2, respectively 0.41 for OC4 to 0.11 for ANN-based pigment algorithm.

4 illus, 2 tables, 10 ref

011171   Biswas S;Sonakia A;Sitaramaiah Y (NO, Geol Surv of India, Nagpur-440 006, Email: arunsonakia@yahoo.com) : Skull of equus namadicus from the middle pleistocene alluvial deposits of narmada valley. J Geol Soc India 2005, 66(4), 438-44.

An extinct species of Equidae, Equus namadicus, is known from the Quaternary alluvial sediments of Narmada valley of central India since the nineteenth century. However, the type skull of the species now in the Natural History Museum of London has never been described systematically. One more skull recovered from the Middle Pleistocene deposits of the same area has been identified as that of E. namadicus and is designated here as paratype of the species. It is one of the largest species of Equus and larger than other Indian species of the genus. Study shows that some specimens of Equus from the Lower Pleistocene deposits of the Siwaliks may be assigned to E. namadicus.

5 illus, 2 tables, 15 ref

011170   Beena Kumari;Mass H;Panigrahy R C;Navalgund R R (Mar and Wat Resour Grp Space Applics Cent, ISRO, Ahmedabad, Gujarat, 380 015, Email: beena@sac.isro.gov.in) : A persistent eddy in the central Arabian Sea: Potential trophic significance. Indian J Mar Sci 2005, 34(4), 449-58.

Arabian Sea is an area of strong currents, complicated flow patterns with several eddies and semi annually reversing monsoon winds. A cold eddy highly rich in phytoplankton in the Central Arabian Sea, centered around: 14ø 25' N and 69ø 20' E during January - March 1998 has been dealt with. The eddy was about 100 km in diameter with a depth of about 4000 m and maximum chlorophyll-a concentration was 1 mg m^-3 compared with 0.2 mg m^-3 in the surrounding areas. Average optical depth of the area was 12 m. The occurrence of the eddy and the related oceanographic variables were inferred from SeaWiFS derived chlorophyll-a (Chl-a), NOAA Pathfinder AVHRR derived sea surface temperature, sea surface height from TOPEX altimeter and collateral information. The cold eddy formation is probably due to longshore density variation in the ocean. Due to negative sea level anomalies, associated surface divergence and upwelling process, the region of cold eddy is known to be highly productive. The cold eddy in the same location was observed during January 2000. The persistence of the eddy for more than a month indicates that this area is a rich forage ground for tuna fishery.

7 illus, 30 ref

011169   Baskar R;Kochhar N (Dep of Envir Sci & Engng, Guru Jambheshwar Univ, Hisar-125 001, Email: rbaskargjuhisar@yahoo.com ) : Alkali amphiboles and pyroxenes from Siwana granite and the associated acid volcanics, Rajasthan. J Geol Soc India 2005, 66(4), 427-37.

Compositional characteristics and substitutional schemes of the amphiboles and pyroxenes of the alkali granites and the associated volcanics around Goliya Bhaylan area are studied. In the alkali granite, the amphiboles evolve from ritchterite to arfvedsonite, in trachytes from winchite to riebeckite and in the case of rhyolites from ritchterite through arfvedsonite to riebeckite with dominant substitution of the type Na^M4 + R³⁺ for Ca + R²⁺. The pyroxenes in alkali granite evolve from hedenbergite to aegirine through aegirine-augite representing the acmitic hedenbergite trend with dominant NaFe³⁺ = Ca (Mg, Fe)²⁺ substitution and a minor amount of NaAl = CaFe²⁺ substitution, whereas the pyroxenes in the acid volcanics are aegirine representing the acmitic trend, with the same substitution characteristics as those found in the alkali granites. The occurrence of Ti-aegirine and aenigmatite is also reported. The chemical trends of the pyroxenes and amphiboles indicate that they are formed from a highly evolved peralkaline residual melt.

6 illus, 4 tables, 29 ref

011168   Ayolabi E A (Dep of Phys, Univ of Lagos, Lagos, Nigeria, Email: eojelabi @yahoo.com) : Geoelectric evaluation of groundwater potential: a case study of Alagbaka primary school, Akure, Southwest Nigeria. J Geol Soc India 2005, 66(4), 491-5.

Vertical electrical sounding consisting of three Wenner array and thirteen Schlumberger array has been carried out at the premises of Alagbaka primary school, Akure Southwest Nigeria. The aquiferous unit in this area is composed of weathered and fractured rocks whose resistivity ranges from 26 to 366 Ωm and thickness of 2.4 to 29.3 m. The isopach shows that the overburden thickens towards the east and is thinnest towards the south. The geological map derived from the coefficient of anisotropy of the underlying rocks shows that the Eastern end underlain by migmatites have coefficient of anisotropy ranging between 1.5 and 2.5 while the southwest, west and northwest side is underlain by charnockites of high (3-7.4) coefficient of anisotropy. The eastern end offers a good prospect for groundwater exploration.

^ccr10 illus, 11 ref

011167   Aswathanarayana U (Mahadevan Int Cent for Wat Resour Mgmt, , Hyderabad, Email: uaswathanarayana@yahoo.com) : Water resources management: how to use science to make informed decisions. J appl Geochem 2005, 7(2), 129-33.

3 ref

011166   Arthur R;Done T;Marsh H (Trop Envir Stud and Geography, James Cook Univ, Townsville Queensland 4811, Australia) : Benthic recovery four years after an El Nino-induced coral mass mortality in the Lakshadweep atolls. Curr Sci 2005, 89(4), 694-9.

The reefs of the Lakshadweep suffered a mass mortality of coral in 1998, in the wake of an El Nino event of unprecedented severity. In 2002, author conducted a broad-scale benthic survey of six atolls in this group to check if there were geographic trends in recovery patterns across the archipelago. Four years after the mass mortality, live coral cover was relatively low on most atolls, and thin algal turfs dominated the benthos. Clear benthic differences were apparent between eastern and western aspects of reefc, pointing to the importance of local hydro-dynamic conditions in determining recovery rates Where recovery was the most apparent, it was dominated by fast-growing and bleaching-resistant coral genera Despite the apparent lack of recovery at many sites the reef system did not show signs of having suffered a 'phase shift' to a macroalgal state. High herbivorous fish abundance was likely responsible in congtrolling macrophyte levels, and may be crucial for further benthic recovery in these reefs.

9 illus, 1 table, 39 ref

011165   Andrade R;Muralidharan D;Rangarajan R (NO, Natn Geophys Res Inst, Hyderabad-500 007) : Pulse responses of an unconfined granite aquifer to precipitation -A recharge evaluation through transient water-level fluctuation. Curr Sci 2005, 89(4), 667-81.

Natural recharge is an important parameter to be known for groundwater budgeting and management Principal source of recharge to the groundwater aquifer system is the percolation of a fraction of rainfall during the monsoon season through the vadose zone. Rainfall recharge is highly variable at a given place and the variability is essentially due to rainfall pattern, soil characteristics remaining the same. Estimation of recharge to an unconfined granite aquifer was made by studying the groundwater response to various rainfall pulses of 2004 monsoon through analysis of continuous hydrograph data, after filtering out extraneous noises like tidal effects. Water-level fluctuation was utilized with precipitation events to evaluate transient recharge rate and cumulative recharge rate was found to be in good agreement with the estimates made by tritium injection method over the monsoon period.

4 illus, 2 tables, 10 ref

011164   Al-Barakati A M (Fac of Mar Sci, King Abdulaziz Univ, P.O. Box 80207, Jeddah 21589, Saudi Arabia) : Monthly variations of the net heat exchange at the water surface near AL-Wajh northern red sea. Bull pure appl Sci-Sect F 2004, 23(1-2), 19-24.

The net rate of heat exchange at the water surface is the sum of the rates at which heat is transferred by radiative processes, by evaporation and by conduction between water and overlying air. The concept of equilibrium temperature and thermal exchange coefficient, both of which depend on meteorological variables, is applied to compute the monthly variations of net heat exchange at the water surface near Al-Wajh. Northern Red Sen. From April to September the net heart exchange is positive i.e the sea gains heat and from October to March it is negative implying that the sea loses heat. The annual average heat loss is about 23w.m^-2.

1 illus, 2 table, 18 ref

010317   Vasudeo A D;Srivastava R (Civ Engng Dep, VNIT, Nagpur-440 011) : Increase in groundwater level due to artificial recharge. ISH J Hydraul Engng 2005, 11(3), 24-31.

Artificial recharge of the groundwater table from rectangular basins has been the subject of extensive study in the last few decades. Authors have developed a numerical model based on the Finite Difference Method with an explicit scheme, to predict the transient position of the water table in response to recharge from a rectangular basin. The rate of recharge is varied applying a time decay constant in order to simulate realistic infiltration behaviour. The modelis validated through comparison with an existing analytical solution and is then applied to estimate the mounding below a proposed recharge basin at the Indian Institute of Technology, Kanpur.

3 illus, 15 ref

010316   Trivedi R K;Singh R M;Tiwari N K (Cent for Advance Stud in Geol Appl Geol Dep, Dr. H.S. Gour Univ, Sagar-470 003, Email: rrmsingh@rediffmail.com) : Hydrological studies of Ghoradongri watershed of Betul district, Madhya Pradesh. J Indian Soc Remote Sens 2005, 33(3), 421-8.

^ssc5 illus, 2 tables, 5 ref

010315   Thomas J V;Parkash B;Mohindra R;Bhattcharya S K;Jani R A (Earth Sci Dep, Indian Inst of Technol Roorkee, Roorkee-247 667) : Syndepositional tectonics and paleoclimatic implications of paleosols of the Plio-Pleistocene Siwalik Group, Haripur-Kolar Section, H.P., India. Himalayan Geol 2005, 26(2), 327-45.

Twenty-eight hundred metre thick succession of the Middle-Upper Siwalik Groups (Plio-Pleistocene) exposed at Haripur-Kolar, Himachal Pradesh, India was subdivided into Unit M1 of the Middle Siwalik and four units U1-U4 of the Upper Siwalik Group (5.5 Ma - 19 Ka) by Thomas et al. (2002). Unit U4 is subdivided into U4a and 4b with boundary at <126>0.90 Ma. This section has been studied in detail for its paleosols and carbon and oxygen isotopes of calcretes to work out changes in paleocimate and mode of formation of paleosols. By comparision with surficial soils of the Indogangetic Plains six pedofacies I-VI have been identified from the Siwalik Groups based on the itensity of soil development and time taken for their development is estimated as 10-100 yrs, 100-500 yrs, 500-2,500 yrs, 2,500-5,000 yrs, 5,000-8,000 yrs, respectively. These data suggest that times accounted by pedogenesis, expressed as a percentage of the total time for units U1-U4, are 14.5, 8.7, 8.5 and 0.35%, respectively. Further Paleosol Facies Association consisting of multiple paleosols with pedofacies III to VI inter-bedded with thin sandstones or well-bedded mud deposits observed from the Siwalik Groups seem to have developed in regions analogous to the modern Upland Interfluves, uplifted from the adjoining large rivers by several meters as a result of syndepositional tectonic activity.

10 illus, 86 ref

010314   Siva Siddaiah N;Sangode S J (NO, Wadia Inst of Himalayan Geol, 33 General Mahadeo Singh Road) : Paleosol development in the Siwalik Foreland Basin: a linkage with uplift, sedimentation and basin subsidence. Himalayan Geol 2005, 26(2), 367-80.

Palleosols are one of the architectural elements of sedimentation in the Siwalik Foreland Basin holding a record of long term climate change for the past 18 Ma. Systematic study of paleosols, and associated non-pedogenic materials, along with their parent rocks are important for understanding pedogenic processes and environments, that in turn gives insight into the interrelation between climate, topography, and ecosystem. Paleosols occur throughout the Himalayan Foreland Basin with variable frequency of occurrence and degree of development; depending upon the basin morphology, rates of sedimentation and subsidence. Many of the paleosol profiles in the Siwalik foreland have well preserved B-horizon characterised by the presence of concretions, peds, Fe-Mn mottling, and pedogenic slickensides. The macro-and micromorphological features such as peds, mottling, iron-oxide coatings, and calcareous nodules associated with the Siwalik paleosols indicate a differential development between the two studied sedimentological settings (Mohand Rao and Haripur sections). The Late Miocene profiles (<126>10 to 5 Ma) in Mohand Rao section are restricted to a maximum of three horizons, whereas the Plio-Pleistocene profiles (<126>6 to 0.5 Ma) in Haripur section consist of three or more horizons. Morphological evolution of the pedofacies indicates relatively better residence time for the Plio-Pleistocene profiles.

10 illus, 2 tables, 46 ref

010313   Sinha S;Sangode S J;Rohtash Kumar;Ghosh S K (NO, Wadia Inst of Himalayan Geol, 33, General Mahadeo Singh Road, Dehra Dun-248 001, Email: sinha_subho@wihg.res.in) : Accumulation history and tectonic significance of the Neogene continental deposits in the west central sector of Himalayan foreland basin. Himalayan Geol 2005, 26(2), 387-408.

A 2.7 km thick Mio-Pliocene Siwalik succession of Ravi re-entrant of the NW Himalayan foreland basin consists of dominantly sandstone-mudstone association in the lower part and sandstone-mudstone-conglomerate in the middle and terminates with thickly bedded conglomerate. The chronology of the sedimentary succession is constrained between 12.775 and 4.480 Ma using magnetic polarity stratigraphy. The average sediment accumulation rate (SAR) derived for the lower 2590 m of the section is 31 cm/1000 yrs with two prominent peaks of higher rates i) 43 cm/1000 yrs a at 8.69 Ma and ii) cm/1000 yrs at 6.93 Ma, separated by a decrease SAR of 26 cm/1000 yrs at 8.25-6.93 Ma. The results obtained from the temporal lithological organization, paleoflow pattern and the net SAR are integrated to decipher the accumulation history in response to various phases of tectonic rejuvenation. The vertical accretion deposits at 9.74-8.25 Ma (1000-1500 m) having lenticular geometry correspond to an active phase of tectonism. At 8.25-6.93, Ma (1500-2000 m) a change in the formative fluvial processes is indicated by the presence of sheet geometry of the channel units and a decrease in SAR points to a quiescent phase. The later increase in the net SAR and the recurrence of the lenticular geometry indicate another phase of tectonic loading and basinal subsidence along the adjacent orogenic front.

13 illus, 2 tables, 54 ref

010312   Singh B P;Mithila;Pawar J S (Postgrad Geol Dep, Univ of Jammu, Jammu-180 006, Email: bpsingh_in@yahoo.com) : A comparison of paleocurrent dispersal in the Tawi river and the Siwalik (Pliocene-Pleistocene) gravelly braid-bars, Jammu area, India. Himalayan Geol 2005, 26(2), 347-56.

Braid-bars are either gravelly or sandy depending upon the discharge, sediment supply, bed-slope of a channel and hinterland lithology. Evaluates flow directions of gravelly braid-bars of the Tawi river near Jammu town, and the Siwalik sucession around Jammu, Jammu and Kashmir State in order to compare modern and ancient paleocurrent patterns and also from the recent sandy braid-bar of the Ganga (Ganges) river. Mean flow directions are linear and oblique to the channel in the Tawi river and moving average diagrams show a linear pattern. The circular standard deviation is low in both the small (36°.7) as well as the large braid-bar (36°.2) of the Tai river, vector means being 263° and 185°, respectively. The azimuthal dispersion is also low (<60>140°) in both braid-bars of the Tawi river. The low values of circular standard deviation and azimuthal dispersion in the gravelly braid-bars suggest straighter flow mainly controlled by slope at high discharges. The boulder conglomerates of the Siwalik Group show unimodal, bimodal, and polymodal paleocurrent patterns, but dominated by a particular mode in corona dot diagrams of individual facies and individual cycles. The azimuthal dispersion of the Upper Boulder Conglomerate is high and have dispersion up to a maximum of 180° in the corona dot diagrams of individual cycles.

11 illus, 2 tables, 49 ref

010311   Sarkar I (Earth Sci Dep, Indian Inst of Technol Roorkee, Roorkee, Email: irenefes@iitr.ernet.in) : Role of small earthquakes in occurrence of moderate earthquakes in the Garhwal Himalaya. Himalayan Geol 2005, 26(2), 357-65.

The role of past small dip-slip and strike-slip earthquakes of the Garhwal region in future moderate earthquake occurrenes is assessed. For this, three representative moderate magnitude events of Garhwal Himalaya that have occurred in the recent past are considered and the (long-term) static stress perturbations on their causative faults contributed by two possible major sources viz. (i) the past small earthquakes of the region and (ii) the subduction of the Indian plate beneath the Garhwal Himalaya are estimated. The calculations indicate that on the causative faults of each of these three moderate earthquakes, the long-term stress changes due to tectonic loading processes is much larger than thatdue to the small events. However, a few favorably located and oriented small dextral strike slip earthquakes induce relatively much larger (long term) static stresses on these moderate earthquake causative faults. The cumulative contribution of transferred stresses from these dextral strike slip earthquakes can become significnat. So much so, that under suitable conditions, together with the other small earthquakes, these small dextral strike slip earthquakes have the capability to cumulatively provide large positive/negative static stresses to a moderate earthquake fault and modulate its time of future failure in a significant way.

3 illus, 44 ref

010310   Rawat R K (Cent of Advd Study in Geol Appl Geol Dep, Dr. H.S. Gour Vishwavidhyalaya, Sagar-470 003, Email: rkrawat04@rediffmail.com) : Geotechnical investigations of Chandmari landslide located on Gangtok - Nathula road, Sikkim Himalaya, India. Himalayan Geol 2005, 26(2), 309-22.

Chandmari landslide is located at the back of Gangtok town at about 11 km on Nathula road. The local people first noticed the slope movement in the year 1966 when a minor subsidence at road level came into sight which is continuously extending during every monsoon, resulting in loss of property, lives and recurrent disruption of the road network. Keeping in view the severity of the problem, the author adopted a systematic approach to study primarily the causes and mechanism responsible for slope failure and secondly to calculate a factor of safety, based on the actual site conditions and the physico-mechanical properties of the slide material. Lastly, an attempt has been made to suggest some remedial measures based on the studies, which might be useful to control further slope movement.

7 illus, 8 tables, 7 ref

010309   Prasad A K;Singh R P (Civ Engng Dep, Indian Inst of Technol, Kanpur-208 016, Email: ramesh@iitk.ac.in) : Extreme rainfall event of July 25-27, 2005 over Mumbai, west coast India. J Indian Soc Remote Sens 2005, 33(3), 365-370.

3 illus, 18 ref

010308   Nageswara Rao P P;Shobha S V;Ramesh K S; Somashekhar R K (NO, Regional Remote Sens Serv Cent, Bangalore-560 070, Email: pinnamaneni1953@yahoo.com) : Satellite-based assessment of agricultural drought in Karnataka state. J Indian Soc Remote Sens 2005, 33(3), 429-34.

1 illus, 1 table, 15 ref

010307   Nagendrappa G (Chem Dep, Bangalore Univ, Central College Campus, Bangalore-560 001, Email: nagendrappa@vsnl.net) : Appreciation of free radical chemistry. Resonance 2005, 10(7), 61-72.

2 illus, 1 table, 2 schemes

010306   Manju Mohan;Mishra M K (Cent for Atmospheric Sci, Indian Inst of Technol, Hauz Khas, New Delhi-110 016) : An observational study of sea breeze characteristics over Kalpakkam coast. Indian J envir Prot 2005, 25(8), 706-17.

An observational study of the sea breeze characteristics has been carried out at Kalpakkam, India which lies on the East coast of Southern Indian peninsula about 700m inland from the sea, the Bay of Bengal. There are clear and significant changes in the surface meteorological parameters at the onset and during sea-breeze phenomenon in the coastal areas. Hourly averaged measurements from a 30m tall micrometeorological tower were used to study the sea-breeze characteristics at the above site. In this study, based on detailed analysis of the data on-set criteria of the sea breeze is characterized by increase in relative humidity at least by 5%, fall in temperature by equal or greater than 0.5 K and increase in wind speed with respect to previous hour record. The study is also compared with the earlier studies in relation to sea breeze carried out at Chennai located approximately 80 km North from Kalpakkam and the differences between these studies are discussed. The comparison of sea breeze characteristics of the study with those from earlier studies that were carried out more than half a century back also reflects the changes due to urbanization and other development activities as well as resulting climatic impacts.

12 illus, 10 tables, 13 ref

010305   Mandal A K;Sharma R C (Soil and Crop Mgmt Dep, Cent Soil Salinity Res Inst, Karnal-132 001, Email: akmondal@cssri.ernet.in) : Compuetrized database on salt affected soils of Haryana state. J Indian Soc Remote Sens 2005, 33(3), 446-55.

^ssc2 illus, 3 tables, 13 ref

010304   Malleswara Rao B N;Umamahesh N V;Thimma Reddy G (Civ Engng Dep, K.I.T.S, Ramtek-441 106) : GIS based soil erosion modelling for conservation planning of watersheds. ISH J Hydraul Engng 2005, 11(3), 11-23.

Universal Soil Loss Equation (ULSE) is used for the estimation of soil erosion. The various ULSE factor such as, soil erodibility, slope, aspect, rainfall erosivity index factor map has been generated by linking the attribute data and digital soil map data. The developed GIS based ULSE factors are used in the soil erosion modelling under alternate land use conditions and the results are compared.

9 illus, 3 tables, 9 ref

010303   Lokesha N;Gopalakrishna G S;Honne Gowda H; Gupta A K (NO, Karnataka St Remote Sens Applics Cent, Bangalore-560 052, Email: ka06r3683@yahoo.co.in) : Delineation of groundwater potential zones in a hard rock terrain of Mysore district, Karnataka using IRS data and GIS techniques. J Indian Soc Remote Sens 2005, 33(3), 405-12.

In the study, the ground water prospect of Mysore district has been delineated using remotely sensing data, base map of GSI, ground truth data, and geographic information system. Based on these integrated studies, it has been noticed that the lithology of the area mainly represents by amphibolite schists, hornblende-biotite gneiss, charnockite, quartzite and granite belonging to Archean to Lower Proterozoic. Resent alluvial deposits mainly occur as valley fills. Major lineaments are mainly confined to valley regions. Structurally the erosional and depositional landforms are occurring as hills, ridges, weathered pediments, weathered pediplains and valley fills. Geomorphology, lineaments, drainage density, type of lithology and surface water bodies are directly influencing the ground water conditions and it is very good in valley regions and in remaining area, it is moderate to poor.

2 illus, 2 tables, 20 ref

010302   Kumar G (Geol Dep, B.I.T. Sindri Instt, Dhanbad-828 123) : Composition and genesis of polymetallic nodules from the central India ocean basin. Indian Min Engng J 2005, 44(2-3), 31-9.

The ferromanganese nodules or simply manganese nodules or more complex polymetallic nodules are widely distributed over extensive areas of seafloor, as well as in many shallow water environments in lakes. They have been extensively studied since their discovery during the HMS Challener expedition, 1873-1876, Muray & Renard (1891). The fact that deep sea ferromanganese nodulesed encrustations can be regarded as an important source of industrial metals like nickel, copper, cobalt and manganese was recognized only within the last four decades, Mero (1965). Within this time many investigations have been carried out in order to determine the quality of composition and the coverage density in the nodule fields so as to find out areas favorable for deep sea mining. Abyssal nodules represent the largest group of ferromagnanese deposits and have been described mainly from the Pacific ocean. The Indian Ocean is next in order while the Atlantic Ocean has the lowest reserves, except the Black Plateau areas. A complex interplay of factors like the degree of oxidation of the depositional environment, abundance of nucleating agents, proximity of source elements, sedimentation rates in the seas, bottom current activity, existence fo benthic organisms, biological productivity in surface waters and many other as yet unidentified phenomena determine nodule density. With an estimated total reserves of 3 x 10¹² tonnes, the nodules represent one of the world's largest untapped deposits of..

8 illus, 3 tables, 18 ref

010301   Krishnakumar G;Gadgil A S;Rajeevan M (NO, India Meteorological Dep, Pune-411 002) : Use of sea surface temperatures over the Indian Ocean in the estimation of tropical cyclone activity over Bay of Bengal. Trans Inst Indian Geogr 2005, 27(1), 63-70.

Estimation of Tropical Cyclone (TC) activities over the Bay of Bengal (BOB) in terms of frequency and cyclone days (CD) using regression equations employing Sea Surface Temperatures (SST) over the Indian Ocean (50° E - 120° E and 30° S - 30° N) based on period of 1950 - 2001 is being attempted in the paper. The set of equations are formulated for the months of May, October, and November, as they are the months with maximum frequencies over BOB. The performance of these equations is found to be 60 to 70 % in the case of frequency estimation with 60 % in the case of CD.

4 illus, 2 tables, 10 ref

010300   Kaushik P;Joshi P K;Yang X (NO, Indian Inst of Remote Sens (NRSA), Dehra Dun-248 001, Email: joshi@iirs.gov.in) : Multiple hazard mapping (MHM) for vulnerability assessment in Pali Gad Watershed using geospatial tools. J Indian Soc Remote Sens 2005, 33(3), 441-5.

^ssc1 illus, 1 table, 15 ref

010299   Kar S (NO, , Rabindra Nagar, Dankuni, Hooghly-712 331) : The giant Asian tsunami. Sci Cult 2005, 71(1-2), 7-11.

6 illus, 1 table

010298   Joshi V U (Geography Dep Postgrad and Res Cent, S.P. Coll, Pune-411 030) : Tsunami: the Killer Wave - that struck the Asian coasts. Trans Inst Indian Geogr 2005, 27(1), 1-18.

On 26th December, 2004, an earthquake of M (magnitude) 9.3 on the Richter scale hit the Indian Ocean along the Sunda Trench. This was the second largest earthquake in modern history. The earthquake generated a Tsunami that devastated coastal areas of 12 countries and the global ripples were so widespread that it caused tidal disturbances in North and South America. Presents a complete report on the event and discusses certain issues connected with the Tsunami. An attempt has also been made to analyze why there had been such a variation in the magnitude of devastations in different coastal localities. As an aftermath of this Tsunami, the Indian government is taking an initiative to install a Tsunami Warning System along the Indian Ocean, which will be in operation from 2007.

1 illus, 4 tables, 15 ref