000130   Raju N V;Prasad B S N;Narasimhamurthy B; Thukarama M (Department of Physics, University of Mysore, Mysore-570 006) : Meteorological and anthropogenic influences on the atmospheric aerosol characteristics over a tropical station Mysore (12°N). Indian J Radio Space Phys 2000, 29(3), 115-26.

Aerosol spectral optical depths (τp) at narrow wavelength bands in the visible and near infrared range are obtained using a ground based multi-wavelength radiometer at the tropical continental station Mysore (12°N, 76°E). These data for a ten-year period (1988-1998) are examined for average temporal and spectral characteristics. The temporal variations reveal a summer high and winter low in τp which get influenced largely by meteorological factors. The spectral features suggest impact of prevailing meteorological processes and probable anthropogenic influence.

000129   Raju D C L;Divakara Rao V;Subba Rao M V (NO, National Geophysical Research Institute, Hyderabad-500 007) : Mafic-ultramafic intrusives in the Kondapalli granulite complex, eastern ghats, India - geochemistry and petrogenesis. Indian Miner 1999, 53(3-4), 133-46.

Kondapalli granulite complex in the Eastern Ghats granulite belt contains, apart from the major khondalite-charnockite association, intrusive rocks of dunite, pyroxenite, amphibolite, norite, gabbro, gabbroic-anorthosite and anorthosite. Detailed major and trace-elemental compositions of these instrusives suggest that the dunite, pyroxenite, amphibolite rocks of the suite are the cumulates and the gabbro-anorthosite suite of rocks are the fractionates of the same source, a basic magma of tholeiite composition. Gradual increase in silica, alumina, LIL and trace elements, and decrease in MgO, FeO^T with limited variation in the alkalies from the cumulate-end to the fractionate-end suggests that the same source (tholeiite- to high alumina?) magma that intruded into the lower crust had fractionated to form the cumulate sequence of dunite, pyroxenite, amphibolite and the fractionate gave rise to the gabbroic anorthosite, anorthositic gabbro and anorthosite by subsequent differentiation. The type of deformation, grade of metamorphism and the structural disposition of the intrusives suggest that the source-magma is a syn- to post-kinematic intrusive and intruded into a substantially thickened crust.

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000128   Rajendra Kumar J;Desai D S (NO, Meteorological office, Pune 411 005) : Monsoon variability in recent years from synoptic scale disturbances and semi-permanent systems. Mausam 1999, 50(2), 135-44.

In the recent decade from 1987 to 1996, the Indian summer monsoon rainfall has shown less interannual variability in comparison with its earlier decade. Except 1987, the area weighted average monsoon rainfall of all other years are within ± 10% (normal) of its long period average value over India. The paper discusses monsoon rainfall and several other associated circulations features with their variability in interannual scale during 1987-96. The results show that though the variability of monsoon rainfall is less during the decade, there is a significant interannual variation in the number of synoptic systems, their days intensities and number of days of presence of monsoon trough and Tibetan anticyclone.

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000127   Rajeevan M;Thapliyal V;Patil S R;De U S (NO, , ) : Canonical correlation analysis (CCA) model for long-range forecasts of sub-divisional monsoon rainfall over India. Mausam 1999, 50(2), 145-52.

Using the canonical correlation analysis (CCA) approach, a forecast model for long-range forecasts of sub-divisional monsoon (June-September) rainfall of 27 meteorological sub-divisions over India was developed. A set of 12 parameters, which have significant correlation with Indian monsoon rainfall, was used as predictors. The model was developed with the data of the period 1958-1994 and by retaining three significant canonical modes. The model showed useful predictive skill in respect of meteorological sub-divisions over central parts of India and NW India with low errors and high skill scores for categorical forecasts. The model showed no predictive skill in respect of meteorological subdivision over south peninsula, Orissa, west Bengal and Bihar. The CCA model has been also found to perform better than another statistical model developed using the 12 same predictors. The CCA model also showed moderate skill in forecasting excess and deficient rainfall categories of sub-divisional monsoon rainfall during the extreme years.

000126   Pitarka A;Graves R;Saikia C;Somerville P (NO, Woodward-Clyde Federal Services, 566 El Dorado Street, Suite 100, Pasadena, CA 91101, USA) : Modeling observed basin-edge effects on strong ground motion. Himalayan Geol 1999, 20(1), 47-57.

It has been observed that large amplification of ground motions caused by the basin edge effect that have been reproduced by the finite-difference modeling. Modeling of ground motions recorded in downtown Kobe, Japan, Los Angeles Basin and Ashigara Valley test site, Japan, suggest that numerical techniques based on finite-differences are very efficient at quantitatively evaluating the amplification of ground motion due to the basin-edge effects at frequencies that are of interest in civil engineering.

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000125   Padmanabhamurty B;Indu Jain (School of Environmental Sciences, Jawaharlal Nehru University, New Delhi-110 067) : Variation of boundary layer heights and eddy diffusivities over dry and moist convective regions of monsoon trough during different phases of monsoon. Mausam 1999, 50(2), 181-6.

Temperature, wind, and humidity data at 6 levels over meteorological towers at Kharagpur and Jodhpur and fast data at Jodhpur (Sonic anemometer at 4m and Gill anemometer at 15m) and Kharagpur (Sonic anemometer at 8m and Gill anemometer at 15m) were analysed. Diurnal variation of boundary layer heights and eddy diffusivity coefficient of momentum, heat and moisture at dry convective region Jodhpur (26.3°N. 73°E) and moist convective region Kharagpur (22.3°N. 87.2°E) of monsoon trough during onset of monsoon, mid-monsoon and end-monsoon phases of the Indian southwest monsoon are studied using micro-meterological tower data. Boundary layer height is computed by eddy correlation (direct method) and profile method (indirect method). Indirect method underestimates the boundary layer height.

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000124   Mukhopadhyay B;Hazra N;Kar S K;Gupta A (NO, Geological Survey of India, 27 J L Nehru Road, Calcutta-700 016) : Geostatistical modelling of Turamdih copper deposit, Singhbhum district, Bihar. Indian Miner 1999, 53(3-4), 147-62.

Chlorite-quartz schist and sericite-chlorite-quartz schist of Precambrian Singhbhum Group in Turamdih area, Singhbhum district, Bihar host a copper-dominated base-metal deposit. Chalcopyrite, the dominant ore mineral, occurs as disseminations, stringers, microlensoid veins and bands parallel to the locally preserved mineral schistosities and as fracture fillings. Statistical and geostatistical techniques were applied for deposit modelling as an aid to establish the mineral inventory. Statistical modelling based on chemical data of megascopically identifiable mineralised sections shows that the copper assay values follow a log-normal distribution with a mean at 0.67 per cent and standard deviation 0.9555. Isotropic semivariography with a spherical model establishes the structural continuity of the sample points. The calculated semivariographic parameters are cross-validated by point-kriging technique. The deposit is subdivided into 9 levels (from 0 m to 160 m) with an interval of 20 m. Block-kriging estimate on these 9 levels is worked out, taking a block size of 5m x 5m x 20m and copper values greater or equal to 1%. The mineral inventory of such blocks at each level and that of the entire deposit was estimated, assuming an average density of 3 gm/cc for the ore-zone rocks at varying cut-off grades and corresponding average grades. The result is graphically displayed by grade-tonnage curves.

000123   Mudgal R;Sharma B;Upadhyay R;Taneja A (Department of Chemistry, St. John's College, Agra-282 002) : Seasonal variation of ambient air quality at selected sites in Agra city. Indian J Radio Space Phys 2000, 29(3), 127-33.

Seasonal variation in the ambient air concentration of SO2, NO2 and suspended particulate matter (SPM) in the urban atmosphere of Agra, India, during the year 1998-99, has been reported. The city was hypothetically divided into six monitoring zones. The maximum concentrations of SO2, NO2 and SPM were observed at Foundry Nagar and St. John's crossing. However, the minimum concentrations of SO2 and NO2 were observed at Dayalbagh, while the SPM concentration were minimum at Tajganj region. The value of SPM was always found higher than the prescribed limit of 100 μgm^-3, while the values of SO2 and NO2 were found within the permissible limits, except sometimes in winter seasons, which may be due to thermal inversion. The value of monthly average pollutant standard index (PSI) has also been reported. The value varies from 127 to 497 in Agra.

000122   Mitra S K (NO, Geological Survey of India, North Eastern Region, Shillong-793 003) : Control of lead-silver mineralisation in Mawmaram area, east Khasi hills, Meghalaya. Indian Miner 1999, 53(3-4), 223-34.

Lead-silver mineralisation occurs as bed-like or lens-like ore bodies parallel to compositional layering of the white quartzite of the Lower Shillong Group. The Shillong Group (Middle Proterozoic) of metasedimentary rocks have undergone four phases of deformation. The earliest structures are tight to isoclinal folds (F1) on bedding plane (SO) with the development of a pervasive axial-planar schistosity (S1). These have been affected by coaxial, open to tight, upright F2 folds with NNE-striking axial plane. NE-trending open recumbent folds (F3) affecting S1 cleavage and F2 axial planes represent structure of the third generation. F1, F2 and F3 are coaxial, plunging moderately towards NE. The latest structures are upright conjugate folds and kink bands (125>4) with axial plane striking N-S, E-W or chevron folds with NW-striking axial plane. The F1 folding is responsible for mobilisation of the ores along the bedding planes and the pronounced concentration near the hinge of the large-scale F1 fold suggesting a strong structural control. The occurrence of sulphide mineralisation, confined to the white quartzite overlying the early Precambrian Granite Gneiss - indicates a stratigraphic and lithological control also. The ore minerals are dominantly galena with subordinate arsenopyrite, loellingite, gersdorffite, safflorite and varying amounts of chalcopyrite, sphalerite, pyrite, pyrrhotite, cubanite.

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000121   Majumdar D;Baruah S K (Department of Applied Geology, Dibrugarh University, Dibrugarh-786 004) : Geology and genesis of pyrite occurrences of Tyrssad area, Meghalaya. Indian Miner 1999, 53(3-4), 205-12.

Pyrite mineralisation has been observed along a NNE-SSW-trending shear zone, about 150-m wide in the Tyrssad area of East Khasi Hills distt., Meghalaya. Geologically, the mineralisation is confined to the shear zone, locally hosted by quartz-muscovite-sillimanite schist belonging to the Mid-Proterozoic Shillong Group. Both disseminated and massive pyrites are recorded. Scanning electron microscopy and transmitted light microscopic study revealed no hydrothermal alteration surrounding the mineralised zone. Massive pyrites are mostly crystalline with dominating cubic crystallinity. Pyrite cubes consist of several thin microplates each measuring about 68μ to 100μ and are highly pitted while some show fracturing. A constant association of pyrite-rich layers with the metasedimentary rocks in the area of study and elsewhere in the shear zone indicates a dominant sedimentary origin. Tectonism and remobilisation due to rising pressure and temperature conditions led to their concentrations along swells bearing total conformity with the schistose plane.

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000120   Kishore P;Reddy K K;Narayana Rao D;Rao P B; Jain A R;Rama G V;Sankar S (Department of Physics, Sri Venkateswara University, Tirupati-517 502) : Statistical comparison of Indian MST radar and rawinsonde wind measurements. Indian J Radio Space Phys 2000, 29(3), 102-14.

Comparison are made between horizontal wind measurements carried out using Indian MST radar at Gadanki (13.47°N, 79.18°E) and rawinsonde launched from SHAR centre, Sriharikota (13.7°N, 80.2°E). The spatial separation of MST radar and rawinsonde is about 90 km. The MST radar horizontal wind velocities are derived from Doppler wind measurements at zenith angle of 20° in two orthogonal plances. For the first time, using Indian MST radar in the tropics, extensive intercomparison results are presented up to an altitude of 18 km. Measurements over a period of 4 months (June - September 1993) are considered, but the major part of the study involves a statistical analysis of data. The intercomparison was carried out using two methods. First, the comparison was made using the entire data obtained from both the instruments. Secondly, the comparison was repeated with data excluded whenever the instruments have large disagreements in excess of ±15 m/s. Comparison of hourly-averaged radar and rawinsonde wind measurements shows fairly good agreement between them. However, the study reveals that radar-derived horizontal winds are underestimated when compared with rawinsonde values over the height range 3.6-18 km. The aspect sensitivity of radar echoes may cause for underestimation of horizontal wind.

000119   Khattri K N (CSIR Emeritus Scientist, Wadia Institute of Himalayan Geology, Dehra Dun 248 001) : Evaluation of earthquake hazard and risk in northern India. Himalayan Geol 1999, 20(1), 1-46.

The seismic hazard in the Garhwal Himalaya and the adjacent Ganga plains due to a future great earthquake (Mw 8.5) assessed by synthesizing accelerograms at a number of sites in the region of the earthquake's influence. The peak ground accelerations over the fault surface attain values in the range of 100% g. Although the values drop off with distance from the fault, the peak accelerations of 48% g are estimated at far off sites like Narora which is on the bank of Ganga where thick loose sediments are present. At Delhi the peak ground acceleration of 22% g can occur. The probability of occurrence of such an earthquake within the next 100 years is 0.59. Considering the dense population level and industrialization of the region the seismic risk is extreme. Immediate initiation of defensive measures to mitigate a future calamity are called for.

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000118   Karmakar P K;Chattopadhyay S;Sen A K;Gibbins C J (NO, Institute of Radiophysics and Electronics, 92, Acharya Prafulla Chandra Road, Calcutta-700 009) : Radiometric measurements of rain attenuation and estimation of rain height. Indian J Radio Space Phys 2000, 29(3), 95-101.

Measurements of rain attenuation at 22.235 and 31.4 GHz have been made during 1991 in Calcutta using microwave radiometers, and compared with calculated attenuation using different rain drop-size distributions. For low rain rates, the Joss et al.'s (drizzle) distribution was found to be the most appropriate. From the radiometric measurements and calculated attenuations, estimates have been made of the rain height and compared with predictions made from the ITU-R model. For the year 1991, the rain height was estimated to be 2.7 km at 22.235 GHz and 2.3 km at 31.4 GHz, as compared to a value of 3.1 km predicted by the IRU-R model.

000117   Kane R P (NO, Instituto Nacional de Pesquisas Espaciais - INPE, ) : Spectral characteristics of the quasi-biennial oscillation of total Ozone. Mausam 1999, 50(2), 187-95.

Twelve-month running means of the 50hPa low latitude zonal wind and total ozone values for the latitutde zones NP (North Polar). NT (North Temperature). TRO (Tropical), ST (South Temperature), SP (South Polar) were subjected to spectral analysis, separately for the two successive 18 year intervals, 1958-1975 and 1976-1993. In the interval 1958-1975, the wind had a prominent peak at 2.45 years and two smaller but significant peaks at 1.98 and 3.05 years. For ozone, only NP, NT and ST had roughly similar peaks (2.37, 2.41, 2.48 years), while TRO and SP had different peaks (2.27 and 2.12 years). All ozone series had significant peaks at 20-21 months, barely significant in the wind series. Ozone peaks were noticed in the 3-5 years band also. In the interval 1976-1993, the patterns were different. The wind had only one prominent peak at 2.51 years. For ozone, NP, NT, ST had roughly similar peaks (2.41, 2.45, 2.45 years) while TRO, SP had different peaks (2.32 and 2.29 years). All ozone series had significant peaks at 20-22 months and in the 3-5 year hand; but these were absent in the wind series.

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000116   Kane R P (NO, Instituto Nacional de Pesquisas Espaciais - INPE, ) : Characteristics of African rainfall. Mausam 1999, 50(2), 159-76.

Each year during 1901-1990 was characterized as having an El Nino (EN) or Southern Oscillation minimum (SO) or warm (W) or cold (C) waters in east equatorial Pacific sea surface or any combination of these, or none (non-events). In contrast to Indian summer monsoon rainfall which showed a very good association between ENSOW type years and droughts, none of the African regions showed any significant, consistent relationship with any combination, except S. Africa where a slight bias for droughts was observed during El Nino years.

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000115   Iyengar R N;Sharma D (NO, Central Building Research Institute, Roorkee-247 667) : Some earthquake of the Himalayan region from historical sources. Himalayan Geol 1999, 20(1), 81-5.

Information about the dates and places of occurrence of earthquake in India prior to 1800 A.D. is woefully scarce in the currently available databases. An effort is made to bring to light several past eathquakes of Kashmir and Assam with their likely dates of occurrence. The recorded places where the effect was felt are traced. The MM intensity in the felt location is estimated based on the textual descriptions.

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000114   Gupta A K (Department of Botany, S H P G College, Baragaon, Varanasi-221 204) : Role of aquatic weeds in harvesting pollutants and conserving nutrients in a river ecosystem. J envir Pollut 2000, 7(1), 47-50.

Weeds, as an integral part of fresh water ecosystem, play a number of diverse roles in determining the structure and function of these systems. Besides being bioindicators of pollution, they efficiently remove minerals from the sediment nutrient pool and thus fight pollution. The study has been performed around Varuna river at Varanasi, which is a tributary of the famous river Ganga, to assess the role of hydrophytes in stripping off nutrients from the water. The levels of N,P,K and heavy metal content were found to be very high in Eicchornia crassipes. Azolla pinnata, Lemna minor, Salvinia molesta, Hydrilla verticillata and Pistia stratiotis. It is recommended that harvesters of heavy metals and nutrients should be favoured for conservation of river ecosystem.

000113   De C (NO, Geological Survey of India, Calcutta-700 016) : Evidence of late triassic volcanism in the Kamthi formation, Talchir coalfield, Orissa. Indian Miner 1999, 53(3-4), 199-204.

Field evidence of Late Triassic volcanism in and around Talchir Gondwana basin of Orissa has been documented in the form of a pyroclastic red shale unit developed within the upper Kamthi Formation. The volcanic origin of the unit is evidenced by the presence of pumice, partly devitrified glass shards, lapilli clasts, flow structures, semiperlitic texture and polygonal shrinkage cracks besides other physical and mineralogical characters. This unit has been equated with 214 <145> 5-Ma-old (Rhaetian) rhyodacitic to decitic volcanism associated with Koel - Auranga river valley basins. This unit can be considered as a Rhaetian marker horizon in the Talchir coalfield. Volcanism comparable to that of the present one in terms of age and composition are known from many southern Gondwanic continents. The pyroclastic unit can serve the purpose of local as well as regional correlation of the Gondwana rock sequences. It also has a bearing on resolving the age cotroversy of the Dicroidium flora and some of the late Triassic vertebrates.

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000112   Chander R;Gahalaut V K (Department of Earth Sciences, University of Roorkee, Roorkee-247 667) : On the cyclic nature of active crustal deformation in the Dehra Dun Himalaya. Himalayan Geol 1999, 20(1), 87-92.

Geodetic observations of crustal deformation in an earthquake prone region are important from the seismic hazards point of view. Levelling observations at six epochs along the Saharanpur-Dehra Dun-Mussoorie highway are now available in the literature. It transpires from the data that, over the Fatehpur to Rajpur segment of the levelling line, ground points which were elevated during the 1905 Kangra earthquake have started to subside.

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000111   Chakraborty B (NO, Geological Survey of India, Coal Wing, Salt Lake City, Calcutta-700 064) : Occurrence of high-potassic trachyandesite near Raigarh town, Madhya Pradesh. Indian Miner 1999, 53(3-4), 187-98.

Occurrence of trachyandesite porphyry near Bhelwatikra, Raigarh district, M.P., extruded along the Southern Main Boundary Fault (SMBF) zone of Raigarh Gondwana Basin, is reported which opens a new vista regarding formation of Mahanadi Gondwana graben. The rock having high K2O, Al2O3 and Rb/Sr ratio contain pink, euhedral orthoclase megacrysts 1cm x 0.05 cm x 0.2 cm, embedded within light green to greenish grey unaltered and little devitrified felsic groundmass. The SMBF zone is highly silicified and brecciated with profuse vein quartz and pegmatites. The andesitic rock is intruded within basement granite, brecciated and silicified zone and also directly in contact with Talchir sandstone of Gondwana basin.

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000110   Chakrabarti D K;Sarkar K (Photogeology and Remote Sensing Division, Geological Survey of India, 29 J L Nehru Road, Calcutta-700 016) : Structural design of natural resources information system in geology (NRIS-G) - a conceptual approach. Indian Miner 1999, 53(3-4), 163-74.

In the proposed information system, five component sub-systems have been primarily designed to be structural in a way so that requisite information at technical, tactical and strategic levels can be serially generated through query-based derivations with provision for self-regulating feed back in the information sub-systems. These sub-systems include: resources data acquisition sub-systems at primary level (RDAS-P) and GIS-database creation sub-system (RDAS-GIS) in acquisition sphere; resources management information sub-system (RMIS-T) at tactical level and resources planning information sub-system (RMIS-S) at strategic level and again; resources utilisation sub-system (RUS-S) at strategic level. All these sub-systems in the hierarchy, can be defined mathematically by linear differential equations of particular order specified by set of distinct input-output information contents in their respective phase spaces. A matrix of total information space can then be obtained by all output information derived at various levels in the hierarchy. The proposed configuration of NRIS-G is flexible and dynamic in nature and can accommodate, according to requirement, any number of information sub-spaces within the sub-system as well as any number of sub-systems within the total system. In addition, conceptual framework of information system-phase space not only determine the logical design of data bases at different nodes but the linkages of data bases, nature of networking.

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000109   Burgmann R;Larson K M;Bilham R (Department of Geology and Geophysics, University of California at Berkeley, Berkeley, CA 94720) : Model inversion of GPS and leveling measurements across the Himalaya : implications for earthquake hazards and future geodetic networks. Himalayan Geol 1999, 20(1), 59-72.

Evaluats the earthquake hazard from the underthrusting of the Indian plate beneath the Himalaya and Tibet, it is essential to map out the locked portions of the fault system that represent future large rupture. A global Positioning System (GPS) network along a <126>500 km long segment of the plate boundary zone in the Nepal Himalaya provides good constraints on the location of the northern tip line of the locked detachment fault in that region. Differences in the deformation patterns between west and east Nepal, suggesting a deeper and slightly clockwise rotated fault system to the West. There is no evidence for significant aseismic strain accommodation along the portion of the Himalaya that did not experience a M≈8 earthquake in the last 300-700 years. GPS measurements in southern Tibet show significant east-west extension that permits arc-perpendicular shortening along the Himalaya.

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000108   Bhattacharya S N (Seismological Observatory, India Mateorological Department, , Lodi Road, New Delhi-110 003) : Perspective of historical earthquakes in India and its neighbourhood upto 1900. Himalayan Geol 1999, 20(1), 117-21.

Study has been carried out on past seismic activity in India and its neighbourhood from ancient times to nineteenth century. During sixth century AD, the great Indian astronomer Varaha Mihira investigated earthquakes in his book `Brihat Samhita'. According to the causes of occurrence, the categorized the earthquakes in 4 classes as: Vayabya; Varuna; Aindra and Agniya. As per the felt area these are assessed as moderate to great earthquakes. According to Varaha Mihira's description, one seismic belt runs north to south along Hazara, Jammu and Kashmir, Punjab, Himachal Pradesh, UP hills and western border of UP, Delhi and Jaipur. Second belt starts at Surat and moves northward to Sourastra and sourastra and southen Rajasthan and then runs eastward to Madhya Pradesh, southern UP, Bihar, Bengal and Tripura. The third belt is along central Kerala and east coast between Tamilnadu and southern Orissa through coastal Andhra Pradesh. Based on scientific reports and few history and geography books, an epicentral map of earthquakes of magnitude 6 and above upto 1900 has been prepared for India and its neightbourhood. The map shows many earthquakes in Pakistan and adjoining Afghanistan, Kashmir and Kutch.

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000107   Begum D A (Department of Physics, University of Chittagong, Chittagong, Bangladesh) : Relation between total ozone and sub-tropical jet steam. Mausam 1999, 50(2), 197-202.

Investigates the relationship between total ozone and subtropical jet steam (STJ). Total ozone data have been obtained from the total ozone mapping spectrometer (TOMS) instrument on the Nimbus - 7 satellite and have been examined in conjunction with meteorological data in the region 90°4 - 160°E, 20°-50°N, i.e., the entrance region of the East Asian STJ from October 1982 to September 1983. The STJ marks the boundary between the high tropical tropopause (ca. 100hPa) and lower subtropical tropopause (ca. 200hPs). In winter it has been found that the total ozone contours are almost parallel to the wind direction, and the horizontal gradient in total ozone increase as the wind speed strengthens.

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000106   Augusthy P O;Joshi S P;Srivastava M M (Ecology Research Laboratory, Botany Department, DAV (PG) College, Dehradun) : Pollution potential of the sewage wastewater of Dehradun. J envir Pollut 2000, 7(1), 73-5.

Sewage wastewater of Dehradun valley was analysed on biomonthly basis. The samples show low dissolved oxygen and high BOD, throughtout the year. TDS and TSS with carbonates and bicarbonates were higher. Calcium, potassium, nitrate, phosphate, sulphate, chloride varied considerably during the study period. Heavy metals analysed for two months show concentration of lead iron chromium, zinc, magnesium. The sewage in untreated condition is toxic.

000105   Arya A S (School of Earthquake Engineering, University of Roorkee, Roorkee-247 667) : Damage scenarios of probable earthquake of M6.5 in U.P. Himalaya. Himalayan Geol 1999, 20(1), 93-103.

000104   Akhtar K;Masroor Alam M;Khan A Z;Ahmad A H M (Department of Geology, Aligarh Muslim University, Aligarh) : Controls of detrital composition of some mesozoic sandstones of western India. Indian Miner 1999, 53(3-4), 213-22.

Deals with the petrofacies analysis of the Mesozoic sandstones of the Jaisalmer Formation (Middle Jurassic) and the Wadhwan Formation (Early Cretaceous) of the Jaisalmer and Saurashtra basin respectively. The role of provenance and other factors controlling the sediment composition are taken into account to understand the evolution of the sandstone and tectonic setting of the basin. The sandstone of Jaisalmer Formation is generally a medium-grained subarkose while that of the Wadhwan Formation is a medium- to coarse-grained quartzarenite. The sandstones plot in mature craton interior and quartzose recycled orogen provenance fields in tectonic distriminating diagrams. This tectonic signature of the petrofacies is primarily due to geomorphic maturity and tectonic stabilisation of the Aravalli-Delhi highlands. Sediment recycling, fairly long transport and subtropical-tropical climate have also played important role in accentuating the quartz and quartzose modes.

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000103    (India Meteorological Department, , New Delhi-110 003) : Measurement of ozone at Maitri, Antarctica. Mausam 1999, 50(2), 203-10.

Regular ozone profile measurement over Antarctica has been made by India Meteorological Department since 1987 at Dakshin Gangotri and later at Maitri (70.7°S, 11.7°E) since 1990 with the help of Indian electro-chemical ozone sonde. Surface ozone measurement was also started at Dakshin Gangotri since 1989 and later at Maitri. Ozone sonde data at Dakshin Gangotri and Maitri have been analysed and ozone hole structure has been studied in detail. The drastic decrease in ozone amount is clearly seen between 100 hPa to 30hPa layer reaching near zero value. Incidently this is the layer where highest ozone concentration occurs during other months except September-October. The ozone hole has been quite severe highest ozone concentration occures during other months except September-October.

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000415   Yusuf Y;Matsuoka M;Yamazaki F (Earthauake Disaster Mitigation Research Centre, National Research Institute for Earth Science and Disaster Prevention, 2465-1 Mikiyama, Midi, Hyogo 673-0433, Japan) : Damage assessment after 2001 Gujarat earthquake using landsat-7 satellite images. J Indian Soc Remote Sens 2001, 16(1-2), 17-22.

Presents a method of earthquake damage detection by comparing the optical images with panchromatic bands for the Gujarat, earthquake, which occurred on January 26, 2001. The data used are optical remote sensing images taken by Landsat-7 satellite on January 8 and February 29, 2001, before and after the earthquake. Investigated the pre and post-earthquake satellite images calculating the differences in the reflection intensity (digital number) of the two images. The estimated affected area has been subtracted on a pixel unit based on the obtained frequency distributions of the differences in the optical sensor values, which show significant changes in the reflectance due to the earthquake disaster. Also investigated the accuracy of the analysis result using a classification method for the training area with aerial photographs taken after the earthquake. The two damage detection methods show a very similar result.

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000414   Sathe P V;Jadhav N (NO, National Institute Oceanography, Dona Paula, Goa-403 004) : Retrieval of chlorophyll from the sea-leaving radiance in the Arabian sea. J Indian Soc Remote Sens 2001, 16(1-2), 97-106.

Error estimates in chlorophyll retrieval in the sea from satellite data have always been higher compared to the errors in retrieval of sea surface temperature or wind speed from satellite data. This is due to the higher percentage of noise in optical signals compared to infrared or microwave signals reaching the satellite. The noise is introduced both at the sea surface itself and also while signal passes passage through atmosphere. An attempt has been made to investigate the noise introduced at the sea surface. During the validation experiment of the optical sensor MOS-B onboard Indian Remote Sensing Satellite IRS-P3, simultaneous measurements of chlorophyll concentration and sea leaving radiance have been made along the satellite passes in the Arabian sea. The algorithms used in the studies are not found to give satisfactory values of chlorophyll in about 30% of cases. The possible sources of errors in retrieving chlorophyll concentration have been discussed.

3 illus, 3 tables, 10 ref 

000413   Sarma V V L N;Kurali Krishna G;Hema Malini B; Rao K N (Geo-Engineering Dep, Andhra University, Visakhapatnam-530 003) : Landuse/landcover change detection through remote sensing and its climatic implications in the Godavari delta region. J Indian Soc Remote Sens 2001, 16(1-2), 85-91.

Interpretation of multi-date satellite imagery has revealed changes in land use/land cover pattern in the Godavari deltaic region during the past 26 years. The area under intensive agriculture has increased from 1459 to 3500 km² and the extent of wetland from 368 to 648 km² during the period 1973-1999, while the seasonal fallow has decreased by 2321 km². Analysis of the climatic data of 1970-1998 from different stations covering the entire 5100 km² area of the delta indicated that the day time temperatures have decreased by 0.2°C to 0.7°C, while the night time temperatures have increased by 0.5°C to 0.6°C during the past three decades. At the same time the rainfall has increased by about 75 to 479 mm. These trends in the climatic parameters are attributed to the increased vegetation cover and wetland extent in the Godavari deltaic region.

3 illus, 3 tables, 9 ref

000412   Sarma K P;Ahmed M;Goswami T K (Department of Geological Sciences, Gauhati University, Guwahati-781 014) : Strain analysis of the Nongkhya conglomerate of Meghalaya. Indian Miner 2001, 55(3-4), 227-36.

The Nongkhya conglomerate of RiBhoi district of Meghalaya separates the basement gneissic and migmatitic complex from overlying Shillong Group of rocks. The magnitude of strain is calculated from the deformed pebbles under a ductile environment of low-grade metamorphism. he direction and the axial ratios of the pebbles have been used to measure the finite strain. The strain analyses reveal that the mean shape of the pebbles was of flattening type and with progressive deformation, the shape of the pebbles changed to constriction type, where the mean values of k varies from place to place. Late shearing was responsible for the rotation of the principal axes of deformed pebbles.

5 illus, 1 table, 17 ref

000411   Sarkar N K;Mallik A K;Panigrahi D;Ghosh S N (NO, Geological Survey of India, DK-6, Salt Lake, Kolkata-700 019) : Occurrence of breccia zone in the Katpal chromite lode, Dhenkanal district, Orissa. Indian Miner 2001, 55(3-4), 247-50.

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000410   Sarkar J (NO, India Meteorological Dep, Pune-411 005) : Distribution of weekly rainfall over heavy rainfall tract of West Bengal. J Maharashtra Agric Univ 2001, 26(2), 180-4.

By fitting Gamma Distribution Model week by week probability of assured rainfall (AR) has been computed at different probability levels (30, 40, 50, 60 and 70%) for 15 locatkions in the heavy rainfall tract of West Bengal comprising of the northernmost Darjeeling, Jalpaiguri, and Coochbehar districts during monsoon season. Accumulated assured rainfall (AAR) analysis reveals that Buxa in Jalpaiguri district received the highest amount AAR and Dinhata in Coochbehar and Pedong in Darjeeling district received the lowest amount of AAR over the tract. A secondary high in AAR was found at Kurseong in Darjeeling district. This investigation gave a clear picture of the week by week distribution of assured rainfall over the belt during the monsoon season. The study could be useful for the tract for developing water resources, planning water use amongst numerous types of consumer (town, industry, agriculture), determining drainage requirements and managing water resources for their most profitable use in crop production.

2 illus, 3 tables, 5 ref

000409   Sarkar B C;Deota B S;Raju P L N;Jugran D K (Indian School of Mines, , Dhanbad) : Geographic information system approach to evaluation of groundwater potentiality of shamri micro-watershed in the Shimla taluk, Himachal Pradesh. J Indian Soc Remote Sens 2001, 29(3), 151-64.

GIS, a potential tool for facilitating the generation and use of thematic information, has been applied to groundwater potentiality of the Shamri micro-watershed in Shimla taluk. The role of various parameters, namely, drainage, lineament, lithology, slope and landuse have been emphasised for delineation of groundwater potential zones. IRS-IC PAN and LISS III FCC merged satellite images on 1:25000 scale and Topographic map no. 53E/4/SE together with field traverses have been used as the data source. A multi-criteria evaluation following probability weighted approach has been applied for overlay analysis that allows a linear combination of weights of each thematic map with the individual capability value. THe resultant map indicates a high groundwater potentiality in the flood plains, river terraces and river channels in the vicinity of the Shamri nala. Other sites of high potentiality include places showing break in slopes and criss-crossing of lineaments.

9 illus, 2 tables, 15 ref

000408   Sarangi R K;Chauhan P;Nayak S (Marine and Water Resources Group, Remote Sensing Application Area, Spa, , ) : Chlorophyll - a concentration along west coast of India using IRS-P3 MOS-B data. J Indian Soc Remote Sens 2001, 29(4), 197-201.

Remote sensing of ocean colour yields information on the constituents of sea water, such as the concentration of phytoplankton pigments, suspended sediments and yellow substrances. It is well understood that the study of ocean colour is significantly related with the primary production and zonation of potential fishing sites in coastal and oceanic waters. The major pigment constitutent is predominated by chlorophyll-a (ocean colour pigment of phytoplankton). The chlorophyll mapping on regular basis plays a major role in assessing water quality and classifying different water types. IRS P-3 MOS-B satellite data for three consecutive passes of path 94, during the period of January-February 1997 have been used to derive chlorophyll-a concentration. Study emphasizes chlorophyll mapping using IRS-P3 MOS-B data for the coastal and offshore water of Maharashtra coast.

3 illus, 1 table, 11 ref

000407   Saif Ud Din;Iqbaluddin (Remote Sensing Applictions Center Aligarh Muslim University, , Aligarh-202 002) : Flood beyond the flood plain in parts of Yamuna Basin are collary to area development. J Indian Soc Remote Sens 2001, 29(3), 183-86.

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000406   Saha A;Mukhopadhyay Basab;Rajendran N (Geodata & Database Division, Geological Survey of India, CHQ, Kolkata-700 016) : GIS integration of exploration datasets to produce a gold potential map for Gadag Schist belt, Karnataka, India. Indian Miner 2001, 55(3-4), 171-84.

Presents an integrated approach to investigate the relationships between geological, geochemical, airborne geophysical and interpreted Landsat imagery data to produce a predictive map using GIS tools. Most of the data used in this study were collected and / or compiled during a collaborative GSI-BRGM project titled "Regional geochemical inventory in selected greenstone belts of Karnataka Craton." During that project ARC/INFO GIS tool was used only for data automation, while statistical analysis and visualisation were done using GDM and SynARC respectively. Integrates all these datasets using Spatial Data Analysis capability of both ARC/INFO & SYNARC and produce a gold potential map for Gadag schist belt, which is a very important part of the greenschist terrain of Karnataka as far as gold mineralisation is concerned. Inut data for the analysis consisted of geological map, stream-sediment-geochemical data (1447 in nos.), heavy-mineral data (127 in nos.), airborne geophysical data, remotesensing data. Known gold occurrences (from existing database) have been used to check the validity of the analyses. These derived maps were weighted and combined to generate the geological Factor, geochemical Factor, heavy-mineral Factor and geophysical Factor Maps. In the last step, the intermediate Factor Maps were combined to produce the Favourability Map.

5 illus, 3 tables, 6 ref

000405   Raut S;Sarma K S S ;Das d k (Water Technology Centre for Eastern Region, , Bhubaneswar-751 023) : Evaluation of irrigation management in a canal command area based on agrometeorology and remote sensing. J Indian Soc Remote Sens 2001, 29(4), 225-8.

Efficacy of irrigation management of wheat and mustard crops grown in Western Yamuna Canal Command area was determined in the present study from agro-climatic data merged with Maximum Likelihood Classified (MXL) satellite image and from irrigation scheduling efficiencies obtained through FAO model CROPWAT. For computing irrigation scheduling efficiencies, amount of water supplied at different growth stages, soil water depletion and crop water need have been taken into account. Agro-meteorological data in combination with MXL classified crop map approximated the deficiency of applied irrigation amount compared to requirement. Irrigations at 35-80 Days After Sowing (DAS) for two times of applications, 30-60-90 DAS for three, 21-50-80-110 DAS in case of four and 20-45-70-90-120 DAS in case of five irrigations have yielded better scheduling efficiencies for wheat than other times of applications in all soil associations.

1 illus, 4 tables, 7 ref

000404   Rao N S;Chakradhar G K J;Srinivas V (Hydrogeology Laboratory, Geology Dep, Andhra University, Visakhapatnam-530 003) : Identification of groundwater potential zones using remote sensing techniques in and around Guntur town, Andhra Pradesh, India. J Indian Soc Remote Sens 2001, 16(1-2), 69-78.

The area in and around Guntur Town in Andhra Pradesh faces an acute water problem. It represents plain land and gentle slope responsible for infiltration and groundwater recharge. Adequate groundwater resource is reported to be available in the investigated area. It has not been properly exploited. Assesses groundwater favourable zones for development and exploration with the help of geomorphological units and associated features. The identified units and features by remote sensing technology with the integration of conventional information and limited ground truths are shallow weathered pediplain (PPS), moderately weathered pediplain (PPM), deeply weathered pediplain (PPD), residual hill (RH) and lineaments (L). The results show that the PPD, PPM and PPS are good, moderate to good and poor to moderate promising zones, respectively for groundwater prospecting. The RH is a poor geomorphological unit in respect to prospective zone as groundwater resource. However, adequate recharge source of groundwater can be expected surrounding the RH, as it acts as surface run-off zone. Lineaments parallel to the stream courses and intersecting-lineaments are favourable indicators for groundwater development. They can also be utilized to augment groundwater resource.

4 illus, 20 ref

000403   Pimprikar S D;Rao P R (Operations M.O.II, Seismic Observatory, Geological Survey of India, Bargi Hills, Jabalpur-482 050) : Analyses of broadband seismological data recorded at the Jabalpur observatory of GSI march 1999 to december 2000 and major seismotectonic features in parts of Sonata zone. Indian Miner 2001, 55(3-4), 185-208.

The local events when correlated with the regional tectonic fabric of the Son - Tapti (SONATA) zone, give interesting information. These events have been further classified as per the tectonic domain or major causative lineament/fault that can be attribted to the event. The cumulative energy release in the zone during the period has been mostly along Son- Narmada South Fault (SNSF) zone and about 99% of this energy is released within 60 km radial distance from Jabalpur town. The Gavilgarh fault zone is the second in order of energy release. However, except for the Jabalpur event of October 17, 2000, it was ahead of the SNSF zone in terms of total energy released. The results for local events have added significantly to the information related to te active tectonic zones, average energy release in SONATA zone. This information in long run will help to concentrate, plan and take effective measures for mitigation of seismic hazard/disk.

8 illus, 17 tables, 26 ref

000402   Pattan J N;Pearce N J G;Banakar V K;Parthiban G (NO, National Institute of Oceanography, Dona Paula, Goa-403 004) : Origin of ash in the Central Indian Ocean Basin and its implication for the volume estimate of the 74,000 year BP Youngest Toba eruption. Curr Sci 2002, 83(7), 889-93.

Controversy exists about the origin of ash in the Central Indian Ocean Basin (CIOB). In situ silicic volcanism and Indonesian are volcanism have been proposed as sources of ash in the basin. Presents the detailed morphology and chemical composition (ten major, 20 trace and 14 rare earth elements (REE)) of glass shards from eight sediment cores in the CIOB to gain insights and provide new estimates of ash volume. The glass shards are of rhyolitic composition with a strong negative Europium anomaly, and show a bubble wall junction-type morphology suggesting a magmatic type of eruption. Major, trace and REE composition and morphology of the shards suggest Youngest Toba Tuff (YTT) of <126>74 ka of Northern Sumatra as the source for the ash. The YTT shards have higher Ca, K, Al, Cs, Ba, Ta, Th, U and heavy REE and lower Fe, Rb, Sr, Y and light REE compared to Middle Toba Tuff, and higher Si, K, Hf and light REE, and lower Ti, Fe, Mn, Mg, Ca, Na, Rb, Sr, Y, Nb, Th, U and heavy REE compared to Oldest Toba Tuff. The YTT covers a new minimum area of <126>3.2x10⁶km² in the CIOB and increases additional ash volume by 160 km² in the CIB and increases additional ash volume by 160 km³ to the earlier volume (350 km³) reported. The new occurrence of YTT from the CIOB, South China Sea and Arabian Sea suggests significant increase in ash volume, and climatic implications need to be reassessed.

4 illus, 3 tables, 27 ref

000401   Pande K (Earth Sciences and Solar System Division, Physical Research Laboratory, , Navrangpura, Ahmedabad-380 009) : Age and duration of the Deccan traps, India: a review of radiometric and paleomagnetic constraints. Proc Indian Acad Sci-Earth Planet Sci 2002, 111(2), 115-23.

Review of the availabale radioetric ad paleomagnetic data from the Deccan Flood Basalt Province (DFBP) suggests that the volcanism was episodic in nature and probably continued over a extended duration from 69 Ma to 63 Ma between 31R and 28N. It is likely that the most intense pulse of volcanism at 66.9 ± 0.2 Ma preceded the Cretaceous Tertiary Boundary (KTB, 65.2± 0.2 Ma) events by <126> 1.7 Ma. The magnetostratigraphic record in the Deccan lava pile is incomplete and it is therefore possible that the lava flows constituting the reverse polarity sequence were erupted in more than one reversed magnetic chron.

3 illus, 51 ref

000400   Obi Reddy G P;Maji A K;Srinivas C V;Thayalan S;Velayutham M (NO, National Bureau of Soil Survey & Land Use Planning, Amaravati Road, Nagpur-440 010) : Landscape ecological planning in a basaltic terrain, central India, using remote sensing and GIS technology. J Indian Soc Remote Sens 2001, 16(1-2), 3-16.

Detailed field survey in conjunction with remotely sensed (IRS-ID, LISS-III) data is of immense help in terrain analysis and landscape ecological planning at watershed level. Geomorphologically, summit crust, table top summits, isolated mounds, plateau spurs, narrow slopes, plateau side drainage floors, narrow valleys and main valley flor were delineated. The soil depth ranges from extremely shallow in isolated mounds to very deep soils in the lower sectors. Very good, god, moderate, poor and very poor groundeater prospect zones were delineated. By the integrated analysis of slope, geomorphology, soil depth, land use/land cover and groundwater prospect layers in GIS, 29 landscape ecological units were identified. Each landscape ecological units refers to a natural geographic entity having distinctive properties of slope, geomorphology, soil depth, land use/ land cover and groundwater prospects. The landscape ecological stress zone mapping of the study area has been carried out based on the analysis and reclassification of landscape ecological units. The units having minimum ecological impact in terms of slope, geomorphology, soil depth and land use/land cover were delineated under very low stress landscape ecological zones. The units having maximum ecological stress in the form of very high slopes, isolated mounds, table top summits and summit crust, extremely shallow soils, waste lands and very poor groundwater prospects were delineated into very high stress landscape ------

8 illus, 3 tables, 22 ref

000399   Mohammed Aslam M A;Balasubramanian A (Center for Environmental Remote Sensing (CEReS), Chiba University, Chiba-263-8522, Japan) : Identification of palaeochannels around Cauvery river near Talakad, Karnataka using remote sensing data. J Indian Soc Remote Sens 2001, 29(4), 237-42.

Visual interpretation of satellite images could help in the identification of present and past landforms. An attempt has been made to identify the palaeochannels of the Cauvery river in Karnataka satate through visual interpretation of IRS-1C, LISS III False Colour Composites (FCC). In order to assess their inter-relationship with other hydrogeomorphic elements, various geomorphic units have been mapped. Major geomorphic units like alluvial plain, pediplain, valley fill, residual hill, ridges, meander scar, channel bars and water bodies have been demarcated. Considering the hydrogeomorphic setup of the palaeochannels. it is inferred that the disposition of palaeochannels of the area are controlled by the geology and structure and the prevailing geomorphic process.

2 illus, 8 ref

000398   Mitra S;Bidyananda M (Geological Sciences Dep, Jadavpur University, Kolkata-700 032) : Minor ore minerals in association with the chromite- and magnetite-amphibolite bodies in Nuggihalli schist belt, Karnataka. Indian Miner 2001, 55(3-4), 237-46.

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000397   Mishra D R;Sahoo A K;Singh R P (Dept of Civil Engineering, Indian Institute of Technology, Kanpur-208 016) : Estimation of monthly rain rate over Indian Ocean region using MSMR data. Curr Sci 2002, 83(7), 877-80.

Efforts have been made to deduce the monthly variations of the rain rate over the oceanic region adjacent to India from July 1999 to June 2000 using brightness temperature data observed by the Multi-channel Scanning Microwave Radiometer (MSMR) sensor on-board IRS-P4 (OCEANSAT). Using brightness temperature measured at 10 and 18 GHz frequencies in horizontal and vertical polarizations, rainfall rate has been compared. The rain rate deduced from MSMR brightness temperature data shows a high value over the ocean during June and July. The rain rate shows moderate to low values during October-November and increases in January, followed by a decrease in March and April, again it increases from May. Variation of rain rate is mainly controlled by summer and winter monsoon. The southwest summer monsoon hists India in May/June; as a result high rain rate, which is responsible for higher rainfall, has been observed over the ocean. Due to the northeast winter monsoon, rain rate increases over the ocean during January-February. The rain rate retrieved from MSMR data is compared with NCEP monthly averaged rain rate.

3 illus, 6 ref

000396   Mane M S;Mahale D M;Dhane S S;More G R (NO, Konkan Krishi Vidyapeeth, Dapoli-415 712) : Meteorological drought analysis based on rainfall data at Panvel. J Maharashtra Agric Univ 2001, 26(2), 191-2.

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000395   Mandal A K;Sharma R C (Soil and Crop Management Division, Central Soil Salinity Research Institute, Karnal-132 001) : Mapping of waterlogged areas and salt affected soils in the IGNP command area. J Indian Soc Remote Sens 2001, 29(4), 229-35.

Visual interpretation of IRS LISS-II data authenticated by ground truth was carried out for detection of waterlogged areas and characterization of salt-affected soils. The deep blue tone depicting surface ponding (stagnant ponded zone) resulted from the seepage and accumulation of irrigation water through the course sandy mass. Such unit was mostly confined to the localized low-lying areas. These data have also revealed interdunal seepage lake within the buried paleo-channel of Saraswati possibly due to submerging of excess Ghaggar floodwater. Flood irrigation, sandy soils, cultivation of high water requirement crops and presence of hard gypsiferrous pans in the shallow depths were responsible for development of waterlogged conditions in the area. The grey to yellowishi white patch around the waterlogging features represented surface salt effloresence. The grey to greyish red represented the potential waterlogging zone. Based on the analytical data, soils were characterized as moderate to highly saline and showed the presence of significant amount of CaCO₃ (<60>2 mm) throughout the solum. The chemical analysis of water samples revealed the presence of high to very high quantity of soluble salts dominated by chlorides and sulfates of sodium, calcium and magnesium.

2 illus, 13 ref

000394   Mahajan S;Panwar P;Kaundal D (GIS lab-cum-Computer Center, Dr Y S Parmar University of Horticulture and Forestry, Nauni, Solan-173 230) : GIS application to determine the effect of topography on landuse in Ashwani Khad watershed. J Indian Soc Remote Sens 2001, 29(4), 243-8.

The landuse status of Ashwani Khad watershed has been obtained using IRS-ID satellite data for 1999 and further topographic analysis has been carried out using GIS software-ARC/INFO and ARCVIEW. It has been found that of the total geographical area (85.30 sq. km) of the Ashwani Khad watershed which lies between 30°50' to 31°N latitude and 77°05' to 77°15'E longitude in Himachal Pradesh, 54.53% constituted wasteland, 33.55% agriculture and least 11.92% forest. The altitude, aspect and slope have exhibited marked effect on land utilization. Agriculture and wasteland have been found maximum in mid altitude (1300-1500 m) and moderate slopes (13.2-26.4 degree), whereas, agriculture and forest have been maximum in flat and north aspect.

1 illus, 3 tables, 3 ref