005626   Pendke M S (College of Agricultural Enginerring, Marathwada Agricultural Univ, Parbhani-431 402) : Assessment of groundwater potential in basaltic watershed. J Instn Engrs-Pt MC 2009, 90(Dec), 8-9.

Pimpri watershed located in Hingoli district, Maharashtra was treated with various soil and water conservation measures like nala bunding, loose boulder dams, earthen plugs, vegetative hedges and contour trenches during the year 1992 to 1993. Four open wells in treated and two open wells in untreated areas of the watershed were selected for monitoring ground water table fluctuations to study the effect of watershed management on increase in ground water potential. Meteorological data, namely, rainfall and evaporation were collected. The hydrologic budget equation (Walton) was used for assessing the gravity yield, which is the change in ground water storage per unit difference in ground water elevation at each well. The gravity yield of 2.2 and 7.2 were observed in treated and untreated watersheds respectively indicating 86.5 increase. Monthly change of 0.22 ha-m/ha and 0.19 ha-m/ha in ground water storage per unit area was calculated for treated and untreated areas respectively. The monthly cumulative ground water potential in both treated and untreated area was calculated. An increase of 40 to 45 in accumulated ground water potential due to watershed management practices was observed in the treated area after a period of four years showing clearly the impact of watershed management.

2 tables, 2 ref

005625   Mishra A (Geology Dep, Lucknow Univ, Lucknow-226 007, Email: ajaimishra2007@yahoo.co.in) : Geomorphic evolution of Gangotri glacier area Garhwal Himalaya, Uttarakhand, India. Res Envir Life Sci 2010, 3(2), 81-88.

Satellite remote sensing coupled with extensive field investigations has enabled to delineate and map the landforms associated with the Gangotri glacier area. The glacier is situated in Uttrakashi district of Uttarakhand Himalaya and shows the presence of a unique set of geomorphic landforms such as transverse glaciers, lateral moraines, recessional moraines, debris cone, pillar like structures, kame terraces, outwash plain and valley terraces. It is observed that the landforms also get modified by the secondary processes such as gravity fall, slope failure and material brought by heavy monsoonal rain. At this stage, the transverse glaciers act as an important agent to carry all the material into the valley. These transverse glaciers are well identified on the satellite data and vary in size from 3 to 20 km long. So, the main glacier and its transverse tributary glaciers together constitute the Gangotri group of glaciers. Kirti, Meru, Gganohim are the transverse glacier which feed the main glaciers from the left, and Raktwarn, Chaturangi, Swachand and Minandi do the same from the right. These lateral glaciers have receded concurrently with the retreat of the trunk glacier. At present, the tributary glaciers are contributing the material due to gravity sliding during heavy monsoonal rains, which dam the fluvial channels and forms lakes and bursting of lakes, leading to flood. The catastrophic floods are thus responsible for the landscape modification in these areas and tributary glaciers act as an agent of reshaping and modification of the landforms. Thus, the landforms and landscape readjust according to the new set of conditions created by the transverse glaciers, and finally get modified. The lateral moraines are the excellent source of information about past glacier size and extent. With the help of satellite data, four stages of lateral moraines can be easily identified in this area and their lateral continuity has been traced for several kilometers down stream of Bhagirathi river, showing the past spatial extent of the Gangotri glacier. Therefore, to study the landforms and their genesis is of prime importance to develop a geomorphic model of the area.

004633   Wadhwa R S;Chudhari M S;Saha A;Mukhopadhyay R;Ghosh N (NO, Central Water and Power Research Station, Pune-411 024, Email: wadhwa_rs@cwprs.gov.in) : Decipherig of weak zones using cross-hole seismic tomography. J Indian Geophys Union 2009, 13(1), 9-16.

Low strain stiffness required for deciding the levels and for designing the foundations of nuclear reactors for dynamic analysis can be determined with depth by cross-hole, up-hole or down-hole seismic techniques utilizing boreholes and polarized or directional energy sources. Of these techniques because of the well defined wave paths, cross-hole technique is the most reliable to measure in situ dynamic properties. Cross-hole seismic studies conducted at a nuclear power plant helped in establishing the foundation level of nuclear reactors as well as for determining the fundamental period of the site. At the same atomic power project site, tomographic studies helped in deciphering the lateral and vertical extent of weak zones with depth. The foundation level of nuclear reactor both from cross-hole and tomographic analysis was evaluated to be at 12 m depth from the ground surface. P-wave tomographic studies revealed that the large region between the boreholes has a compressional wave velocity over 5 km/sec which is indicative of good quality basalt, devoid of any major fracture zone or cracks. Three weak zones of limited lateral and vertical extent inferred from the P- wave velocity tomogram should be treated to avoid any adverse effect on the foundation of nuclear reactors particularly in case of earthquake. The velocity tomogram revealed that the velocity distributions in the horizontal and vertical directions are similar which indicated that stresses both in horizontal and vertical directions are of the same order. Small abnormal features observed on the tomogram should be ignored because both technique and data can not resolve the small features. These features were attributed to error in picking arrival times, less ray density both near source and receiver hole or scattering of waves from small inhomogeneities.

4 illus, 14 ref

004632   Vichare G;Rajaram R (NO, Indian Institute of Geomagnetism, Plot No-5, Sector-18, New Panvel, Navi Mumabi-410 218, Email: geeta@iigs.iigm.res.in) : Comparative study of models of earth's magnetic field derived from oersted, CHAMP and SAC-C magnetic satellite data. J Indian Geophys Union 2009, 13(1), 33-42.

The magnetic field near the earth contains contribution from three major sources, viz., main internal field that is due to electric currents in the outer core (97-99%), crustal field (1-2%), and external field (1-2%). The external field includes contribution due to ring currents, magnetotail, magnetopause currents and also subsurface currents induced by them. Over the past decade or so, there has been an attempt at "comprehensive modeling" that seamlessly integrates data collected over different epochs and different platforms to generate an integrated magnetic field model. It is found that the estimate of the contribution from ionospheric currents using satellite observations is sensitive to the Earth's magnetic field models, and hence it is essential to compare various magnetic field models. In the present work, we compare CHAOS model, the most recent long term model of Earth's magnetic field that uses Oersted, CHAMP and SAC-C satellite data with earlier epoch based models such as Oersted Initial Field Model, (OIFM) and CO2 models. CO2 model utilizes magnetic measurements from all three satellites as well as ground observatory data, whereas OIFM uses single satellite observations. While both CHAOS and CO2 models expand the static (core and crustal) field up to high order spherical harmonic (n = 50 and 49 respectively), OIFM has expansion only upto degree n = 13. The present study systematically separates and discusses the contribution from the various sources. The match between the internal field obtained from OIFM and CHAOS is found to be good in the longitudinal belt between 150°E and 250°E, indicating that in this longitude zone, the contribution due to the long wavelength crustal field is minimum. It is also observed that the difference between the internal field of OIFM and CHAOS is maximum along Indian and American sectors. Present work estimates the magnetic field variations due to the ring current, induced current, and magnetotail current, as well. It is found that the ring current contribution using OIFM is stronger compared to other two models. The external field due to ring current is discovered to be largest and that of due to the tail current is weakest. The effect of the tail current on the surface of the globe is found to be almost same everywhere, due to its far location. It is evident that in general, the ring current contributions are about five times stronger than that of due to the induced currents.

5 illus, 18 ref

004631   Thakur G S;Raghuwanshi R S (Geology Dep, Govt. Motilal Vigyan Mahavidyalaya, Bhopal, Madhya Pradesh-462 008, Email: rsraghuwanshi@rediffmail.com) : Perspect and assessment of groundwater resources using remote sensing techniques in and around choral river basin, Indore and Khargone districts, M.P.. J Indian Soc Remote Sens 2008, 36(2), 217-25.

The study area around Choral river basin in the Narmada valley region, forms a part of Indor and Khargone districts of Madhya Pradesh. The geological, gcomorphologic, lineament, hydro-geomorphie and groundwater potential zone maps of the study area have been prepared using IRS IC LISS HI FCC imagery on 1:50,000 scale. Varievis lithe-units, different band forms, lineament fabric and hydro-geomorphic units have been worked out by visual interpretation methods and frequent field checks. The integrated hydro-geomorphological map of the study area reveals that the groundwater potential in denudation landforms such as buried pediplains, plateaus, denudational and residual hills is moderate-to-poor. On the other hand, the ground-water occurrence in structural land forms like struc-tural hills, lineaments/faults and narrow gorges is likely to be good to- modwate and the depositional landforms namely aluvial plains, valley-fills and meandering-channels favour the accumulation of sub-surface water and, therefore, may be considered as good recharge zones. From the point of view of groundwater occurrence, various hydro-geomorphic unjts have, been classified as high, moderate and low potential zones.

3 illus, 2 tables, 10 ref

004630   Suresh Kumar;Anil Kumar;Saha S K;Ajay Kumar (NO, Indian Institute of Remote Sensing, Dehradun-248 001, Email: suresh_kumar@iirs.gov.in) : Stereo cartosat-1 satellite remote sensing data in assessing topographic potential of soil erosion. J Indian Soc Remote Sens 2008, 36(2), 159-65.

Stereo Cartosat-1 satellite data was processed to generate high spatial resolution digital elevation model (DEM) using ground control points (GCPs) collected through geodetic single frequency GPS in differential GPS mode. DEM was processed to generate bare earth DEM by removing heights of natural and man made features from DEM. The bare earth DEM was further analysed in GIS environment to generate terrain-topographic indices viz. wetness index (WI), stream power index (SPI) and sediment transport index (STI) to characterize topographic potential of soil erosion. Hillslopes in the studied watershed (part of Shiwalik hills of Dehradun district, Uttarakhand state) were characterized as low wetness index values indicating dry areas whereas high wetness index values at lower reaches of the watershed indicating as possible source areas for generation of saturated overland flow. Higher STI values were observed in hilly as well as upper part of the piedmont plain and at along sides of the streams in upper piedmont indicating areas susceptible to severe soil erosion. GIS based these topographic indices provided an easy and quick appraisal and scientific basis to identify spatial variability of soil erosion risk in a hilly watershed.

6 illus, 22 ref

004629   Sinha R;Bapalu G V;Singh L K;Rath B (Civil Engineering Dep, IIT Kanpur, Kanpur-208 016, Email: rsinha@iitk.ac.in) : Flood risk analysis in the Kosi river basin, North Bihar using multi-parametric approach of analytical hierarchy process (AHP). J Indian Soc Remote Sens 2008, 36(4), 335-49.

The Kosi river in north Bihar plains, eastern India presents a challenge in terms of long and recurring flood hazard. Despite a long history of flood control management in the basin for more than 5 decades, the river continues to bring a lot of misery through extensive flooding. This paper revisits the flooding problem in the Kosi river basin and presents an in-depth analysis of flood hydrology. We integrate the hydrological analysis with a GIS-based flood risk mapping in parts of the basin. Typical hydrological characteristics of the Kosi river include very high discharge variability, and high sediment flux from an uplifting hinterland. Annual peak discharges often exceed the mean annual flood and the low-lying tracts of the alluvial plains are extensively inundated year after year. Our flood risk analysis follows a multi-parametric approach using Analytical Hierarchy Process (AHP) and integrates geomorphological, land cover, topographic and social (population density) parameters to propose a Flood Risk Index (FRI). The flood risk map is validated with long-term inundation maps and offers a cost-effective solution for planning mitigation measures in flood-prone areas.

9 illus, 2 tables, 28 ref

004628   Singh A K;Singh P K;Lal B;Singh A N;Mathur A (NO, JNKVV Krishi Vigyan Kendra, Katni-483 442, Email: singhak123@rediffmail.com) : Distribution analysis of salt affected soils under canal and non-canal command area in a part of Etah district, U.P., using remote sensing technique. J Indian Soc Remote Sens 2008, 36(2), 183-8.

Remote sensing provides a lucid and effective means for crop coverage identification. Crop coverage identification is a very important technique, as it provides vital information on the type and extent of crop cultivated in a particular area. This information has immense potential in the planning for further cultivation activities and for optimal usage of the available fertile land. As the frontiers of space technology advance, the knowledge derived from the satellite data has also grown in sophistication. Further, image classification forms the core of the solution to the crop coverage identification problem. No single classifier can prove to satisfactorily classify all the basic crop cover mapping problems of a cultivated region. We present in this paper the experimental results of multiple classification techniques for the problem of crop cover mapping of a cultivated region. A detailed comparison of the algorithms inspired by social behaviour of insects and conventional statistical method for crop classification is presented in this paper. These include the Maximum Likelihood Classifier (MLC), Particle Swarm Optimisation (PSO) and Ant Colony Optimisation (ACO) techniques. The high resolution satellite image has been used for the experiments.

4 tables, 4 ref

004627   Shanwad U K;Patil V C;Gowda H H;Dasog G S (NO, Agricultural Sciences Univ, Dharwad-580 005, Email: shanwad@gediffmail.com) : Application of remote sensing technology for impact assessment of watershed development programme. J Indian Soc Remote Sens 2008, 36(4), 375-86.

The current study was taken up to investigate the utility of remote sensing and GIS tools for evaluation of Integrated Wasteland Development Programme (IWDP) implemented during 1997-2001 in Katangidda Nala watershed, Chincholi taluk, Gulbarga district, Karnataka. The study was carried out using IRS 1C, LISS III data of December 11,1997 (pre-treatment) and November 15, 2002 (post-treatment) covering the watershed to assess the changes in land use / land cover and biomass that have changed over a period of five years (1997-2002). The images were classified into different land use/land cover categories using supervised classification by maximum likelihood algorithm. They were also classified into different biomass levels using Normalized Difference Vegetation Index (NDVI) approach. The results indicated that the area under agriculture crops and forest land were increased by 671 ha (5.7%) and 1,414 ha (11.94%) respectively. This is due to the fact that parts of wastelands and fallow lands were brought into cultivation. This increase in the area may be attributed to better utilization of surface and ground waters, adoption of soil and water conservation practices and changes in cropping pattern. The area under waste lands and fallow lands decreased by 1,667 ha(14.07%) and 467 ha (3.94%), respectively. The vegetation vigour of the area was classified into three classes using NDVI. Substantial increase in the area under high and low biomass levels was observed (502 ha and 19 ha respectively). The benefit-cost analysis indicates that the use of remote sensing and GIS was 2.2 times cheaper than the conventional methods. Thus, the repetitive coverage of the satellite data provides an excellent opportunity to monitor the land resources and evaluate the land cover changes through comparison of images for the watershed at different periods.

5 illus, 2 tables, 23 ref

004626   Sanjay Kumar;Singh A K;Prasad A K;Singh R P (Physics Dep, Banaras Hindu Univ, Varanasi-221 005) : Annual variability of water vapor from GPS and MODIS data over the indo-gangetic plains. J Indian Geophys Union 2009, 13(1), 17-23.

The knowledge of water vapor variability is important at any location in India for weather forecast, numerical weather prediction and also in the early information about the onset of monsoon. In the absence of ground observations, the satellite remote sensing and the Global Positioning System (GPS) have emerged as an important tool in estimation of water vapor. The total column atmospheric water vapor, obtained from Global Positioning System (GPS) and Moderate Resolution Imaging Spectroradiometer (MODIS), is found to be very dynamic over the Indo-Gangetic (IG) plains. In this paper, we present our preliminary analysis of GPS along with satellite (MODIS) derived water vapor and its annual variability over the IG plains of India (Varanasi - BHU station and Kanpur -IITK station) during the period January 2007 to December, 2007. The monthly and seasonal variations of water vapor show strong variability and its relation with the monsoon. The role of GPS and satellite derived meteorological parameters in understanding the dynamics of the monsoon and climate conditions over Indian sub-continent are discussed.

3 illus, 1 table, 17 ref

004625   Rudraiah M;Govindaiah S;Srinivas Vittala S (Geology Dep, Manasagangotri Mysore Univ, Mysore-570 006, Email: vittala_99@rediffmail.com) : Morphometry using remote sensing and GIS techniques in the sub-basins of Kagna river basin, Gulburga district, Karnataka, India. J Indian Soc Remote Sens 2008, 36(4), 351-60.

The study area is a part of Kagna river basin in the Gulburga district of Karnataka, India. It covers an area of 1320 km₂ and it has been subdivided into 4 sub-basins namely Wadi, Chitapur, Sedam and Kurkunta, which range in area from 184 to 537 km². The drainage pattern of these sub-basins are delineated using Geo-coded FCC bands 2,3,4 of IRS 1C and 1D(LISS III+PAN merged) on 1:50,000 scale and Survey of India toposheets as reference. The morphometric parameters are computed using ArcInfo and Arc View GIS softwares. The drainage pattern of the study area is dendritic to sub-dendritic with stream orders ranging from IV to VII orders. Drainage density ranges from 1.40 to 1.86 km/km² suggesting coarse to moderate drainage texture. The change in values of stream length ratio indicate their late youth stage of geomorphic development. The values of bifurcation ratio ranging from 2.00 to 4.71 indicate that all the sub-basins fall under normal basin category. The values of form factor and circulatory ratio, suggest that the Kurkunta sub-basin is elongated and the remaining sub-basins are more or less circular in shape. Elongation ratio indicates that the Wadi sub-basin is a region of very low relief whereas the other sub-basins are associated with moderate to high relief and steep ground slopes. It is concluded that remote sensing and GIS have been proved to be efficient tools in drainage delineation and updation. In the present study these updated drainages have been used for the morphometric analysis.

1 illus, 2 tables, 23 ref

004624   Roy P N;Mondal S K (Applied Geophysics Dep, Indian School of Mines Univ, Dhanbad, Jharkhand-826 004, Email: pnsmay1@gmail.com) : Fractal nature of earthquake occurrence in northwest Himalayan region. J Indian Geophys Union 2009, 13(2), 63-8.

The Himalaya has seen many earthquakes in past ranging from low to very high magnitude causing massive losses. Earthquakes in Himalaya are mainly caused due to release of elastic strain energy created and replenished by persistent collision of the Indian plate with the Eurasian plate. In this paper the fractal analysis were done for earthquakes (mb ≥ 3) occurred during 1973 - 2008, which led to the detection of a clustering events in three consecutive fifty events window having low DC value ranging from 0.932 to 0.533 during the period between 12.9.2004 to 28.2.2005.Spatio-temporal clustering of events apparently indicates a highly stressed region, leading to increase of shear strain causing weak zone from where the rupture propagation may eventually nucleate causing large earthquake. This kind of clustering pattern study using well-constrained catalogue data for the Himalayan fault systems of seismically active region can eventually help in the preparedness and mitigation of earthquake hazard.

3 illus, 1 table, 27 ref

004623   Rashpl Kaur;Ganju A (Snow and Avalanche Study Estt, RDC SASE, Him-Parisar, Plot No. 1 Sector 37A, Chandigarh, Email: rashpalkaur@gmail.com) : Cloud classification in NOAA AVHRR imageries using spectral and textural features. J Indian Soc Remote Sens 2008, 36(2), 167-74.

Clouds contribute significantly to the formation of many of the natural hazards. Hence cloud ' mapping and its classification becomes a major component of the various physical models which are used for forecasting natural hazards. The problem of cloud data classification from NOAA AVHRR (advance very high resolution radiometer) satellite imagery using image transformation techniques is considered in this paper. The singular value decomposition (SVD) scheme is used to extract the salient spectral and textural features attributed to satellite snow and cloud data in visible and IR channels.

5 illus, 1 table, 11 ref

004622   Raju K N P;Sarvajeet Kumar;Mohan K;Pandey M K (Geography Dep, Banaras Hindu Univ, Varanasi-221 005, Email: prudhvigeobhu@gmail.com) : Urban cadastral mapping using very high resolution remote sensing data. J Indian Soc Remote Sens 2008, 36(3), 283-8.

With growing urban expanses, one of the pre-requisites for effective governance is Urban Information Systems (UIS) with content down to individual properties (and individuals). The basic input i.e., a map, in UIS should show individual property boundaries showing the plan outline of all structures existing within, at a scale of 1:1000 and larger with sub-metre to centimeters planimetric and geometric accuracy. With very high resolution remote sensing data of the order of 1m available in hand, it is possible to prepare maps with high resolution spatial content. The present exercise demonstrates a method of preparing a geometrically and planimetrically accurate urban cadastral map on very large scale for a small area of about 5 sq km. IKONOS merged data with 1m resolution is used for the purpose. Mapping was done in conjunction with on-site measurements and sketches. Guides are used to maintain shape symmetry and accuracy of buildings and other features. Working out cost of mapping per unit area is another objective in the present exercise. For want of fully or semi-automatic methods of information extraction from very high resolution remote sensing data, it is imperative that mapping should be carried out in conjunction with some on-site measurements wherever necessary.

3 illus, 6 ref

004621   Raaj R;Ramalingam M;Ghosh S K;Kothyari U C (Civil Engineering Dep, Indian Institute of Technology Roorkee, Roorkee-247 667, Email: ramsankaran_raaj@yahoo.co.in) : Mapping of suspended sediments using site specific seasonal algorithms. J Indian Soc Remote Sens 2008, 36(1), 61-8.

Reports a preliminary work in which two site specific seasonal algorithms have been proposed for estimating the suspended sediments concentration (SSC) from the digital numbers recorded on Indian Remote sensing Satellite, IRS-P4 Ocean Colour Monitor (OCM) sensor. For estimation of SSC, the proposed algorithms utilize dark pixel deduction atmospheric correction technique. The computations are performed with respect to north east monsoon phase situations of Palk Strait coastal stretch. The algorithms performance was satisfactory during the north east monsoon period. Although the results obtained cannot be generalized, we suggest that the authority of proposed algorithms can be extended to other seasons with the addition of more temporal experimental validation data sets and with numeric constants adjusted to present existing conditions. (As this area was severely affected by Tsunami, it may have dissimilar conditions at present).

4 illus, 1 table, 14 ref

004620   Pati J K;Lal J;Prakash K;Bhusan R (Earth and Planetary Sciences Dep, Nehru Science Centre, Allahabad Univ, allahabad-211 002, Email: jkpati@yahoo.co.in) : Spatio-temporal shift of western bank of the Ganga river, Allahabad city and its implications. J Indian Soc Remote Sens 2008, 36(3), 289-97.

Ganga is one of the largest rivers of the world which supports millions of population on its banks. It is a tectonically controlled Himalayan river which also creates havoc due 19 perennial floods every year. Like most large river systems, it also shifts its course in the Gangetic plains in space and time. The present study measures the variable shift in a selected flood-prone stretch of the Allahabad city lying on the western bank of the Ganga river, taking into account the historical, annual to monthly data (including pre- and post-monsoon shifts) to show the ongoing changes in the river course with possible causes and futher implications. It also discusses for the first time the down stream effect of the Tehri dam on the Ganga river course after it became functional.

^ssc5 illus, 1 table, 22 ref

004619   Panigrahi J K;Tripathy J K;Umesh P A (Marine Science Dep, Berhampur Univ, Orissa, Email: jeetendra@scientist.com) : Optimum tracking of ship routes in 3g-WAM simulated rough weather using IRS-P4 (MSMR) analysed wind fields. J Indian Soc Remote Sens 2008, 36(2), 149-58.

Rough weather ship routing is studied using model hindcast wave climate. With the launch of IRS-P4 (OCEANSAT-I), it became possible to carry out routine wave forecasting over the Indian Ocean. The MSMR channel of the satellite gives scalar wind, which is analysed at National center for Medium Range Weather Forecasting (NCMRWF), India for converting to vector winds. The same is used as input to third generation wave model for the rough weather month of July 2000. Simulations are carried out using Cycle-4 of third generation spectral wave model WAM for regional grid system. This simulated wave climate formed the basis for computing effective ship velocity in the irregular seaway. This study gives a quantitative estimation of change in ship velocity in the open Indian Ocean for a Liberty type ship. The optimal route is charted using Dijkstra's algorithm for minimal time path between Calcutta and Sumatra. The optimum track information has broad scope for obtaining a safer route, least time route by avoiding delay in schedule with minimum fuel consumption.

8 illus, 1 table, 8 ref

004618   Naik D R;VenkateswaraRao T;Prakasa Rao B S; Venkateswarlu N (Geo-Engineering Dep, College of Engineering, Andhra Univ, Visakhapatnam-530 003) : Spatio-temporal change study on wetlands of Krishna delta using remote sensing techniques. J Indian Geophys Union 2009, 13(1), 25-32.

An attempt has been made to map and record the land use/land cover changes with reference to wetland in and around the Krishna delta region over a period of 17 years (1983 - 2000) based on interpretation of digital remote sensing data. On-screen visual interpretation was carried out on IRS - 1A (LISS I) and 1C (LISS III) digital imageries for the years 1990 and 2000 respectively coupled with field observations. Comparison of the SOI toposheet (1983) and IRS imageries resulted changes due to natural and man made activities in the study area over period of 17 years. Tremendous change has been observed in mangroves, mudflats, sandy area and plantations. The area under mangroves was decreased from 22,500 ha in 1983 to 9633 ha in 2000. Mudflats were decreased from 8700 ha to 6300 ha. About 39 % increase in plantation and 43.15% increase in sandy area has been observed from 1983 to 2000. It is concluded that most of wetlands mudflats, mangroves and agriculture land were converted to aquaculture (35,000 ha) which was not existing in 1983. This change in delta lead to the deposition of sand/silt and polluted water to the lower reaches result in mangrove degradation and sand deposition. This paper presents the role of remote sensing studies in assessing the land use changes in unapproachable wetlands in the Krishna river delta.

5 illus, 2 tables, 18 ref

004617   Nagaraju D;Ravikumar N (Studies in Geology Dep, Manasgangothri, Maysore-570 006) : Drainage morphometric analysis of Gundlupet taluk, Chamarajanagar district, Karnataka, India. J Ecotoxic envir Monit 2009, 19(2), 193-200.

The study area covers 1406 km² comprising of 8 sub basins of Gundlupet Taluk, Karnataka. The morphomteric analysis of 9 sub basins has been carried out and the drainage network shows that the terrain exhibits dendritic to sub dendritic drainage pattern, stream orders range from fourth to fifth order. Drainage density varies between 1.65 and 2.86 km/km² and has very coarse to coarse drainage texture. The relief ratio ranges from 0.008 to 0.061. The mean bifurcation ratio varies from 3.81 to 4.68 and fells under normal basin category. Hence, it can be concluded that the techniques proved to be competent in morphometric analysis.

1 illus, 2 tables, 20 ref

004616   Nagaraju D;Papanna C (Geology Dep, Manasagangotri Univ, Mysore-570 006) : Groundwater exploration for tapping the deeper potential aquifers in hard rock terrain of Udigala watershed, Chamarajanagar District, Karnataka. J Ecotoxic envir Monit 2009, 19(4), 389-6.

Potential deeper aquifers have been tapped by means of groundwater exploration aided by proper study of lineaments along with field investigation in parts of drought prone Udigala watershed. Chamarajanagar district, Karnataka state. Several high yielding wells have been constructed in the study area, the depth of the wells ranges between 94 and 180 meters. Two to six water bearing fracture zones have been encountered within a depth of 110 m and all these wells are located at close proximity of North east -South west trending lineaments. Other North west-South east trending sets of lineaments are less developed. The North east - South west lineaments are possibly by surfacial signature of resultant tensional joints/ fractures perpendicular to the direction of compression, which would have acted in the area resulting into deep potential fracture/aquifers for groundwater.

5 illus, 2 tables, 9 ref

004615   Mondal M S;Pandey A C;Garg R D (Remote Sensing Dep, Birla Institute of Technology, Mesra, Ranchi, Email: garg_fce@iitr.ernet.in) : Groundwater prospects evaluation based on hydrogeomorpho-logical mapping using high resolution satelite images: a case study in Uttarakhand. J Indian Soc Remote Sens 2008, 36(1), 69-76.

Water is the most important natural I resource which forms the core of the ecological system. The advent of remote sensing has opened up new vistas in groundwater prospect evaluation, exploration and management. The groundwater resources of the study area, Rishikesh region of Garhwal Himalayas, are under threat due to population pressure caused by expanding tourism in this region. This entails sustainable and judicious use of this precious resource. The groundwater prospect evaluation in Rishikesh region has been attempted based on hydrogeomorphological mapping of the area consisting of thematic maps of hydrogeomorphology, geology, drainage, lineament, slope and relief using high resolution IRS-1C LISS III and PAN merged satellite images. The Rishikesh region exhibits diverse hydrogeomorphological conditions where the groundwater regime is controlled mainly by topography and geology. A probability-weighted approach has been applied during overlay analysis in ArcMap GIS environment. The overlay analysis allows a linear combination of weights of each thematic map with respect to ground water potential. Good groundwater prospects dominate in the area with more than 50% of the study area showing moderate to excellent potential. The study shows that the remote sensing and geoinformatics techniques can be applied effectively for groundwater prospect evaluation.

3 illus, 3 tables, 9 ref

004614   Mitra A K;Nath S;Sharma A K (SATMET Div, India Meteorological Dep, New Delhi-110 003, Email: ashim_mitra@rediffmail.com) : Fog forecasting using rule-based Fuzzy inference system. J Indian Soc Remote Sens 2008, 36(3), 243-53.

Operational meteorology is perceived as a fuzzy environment in which information is vaguely defined. The mesoscale processes such as fog, stratus and convection are generally dependent on the topography of the place and has always been difficult to forecast for the meteorologists. The main objective of the present study is to introduce the concept of fuzzy inference system (FIS) in the prediction of fog. This approach uses the concept of a pure fuzzy logic system where the fuzzy rule base consists of a collection of fuzzy IF-THEN rules. The fuzzy inference engine uses these fuzzy IF-THEN rules to determine a mapping from fuzzy sets in the input universe of discourse to fuzzy sets in the output universe of discourse based on fuzzy logic principles. Basic weather elements, which affect weather characteristics of fog, are fuzzified. These are then used in fuzzy weather prediction models based on fuzzy inferences. These models are simulated and the crisp results obtained using developed defuzzification strategies are compared with the actual weather data. The basis of methodology is to construct the fuzzy rule base domain from the available daily current weather observations in winter season over New Delhi. The results reveal that dew point spread and rate of change of dew point spread are the most important parameters for the formation of fog. The results further indicate that fog formation over New Delhi are dominant when (i) dew point is greater then 7°C along with dew point spread between 1 and 3°C. (ii) rate of change of dew point spread must be negative and wind speed should be less than 4 knots. This study presents a technique for predicting the probability of fog over New Delhi for 5-6 hours in advance. The skill score indicates that the performance of FIS is appreciably good. The method is found to be promising for operational application.

4 illus, 3 tables, 17 ref

004613   Miglani A;Ray S S;Pandey R;Prihar J S (ARG/RESIPA, Space Applicatins Centre, ISRO, Ahmedabad-380 015, Email: ssray@sac.isro.gov.in) : Evaluation of EO-1 hyperion data for agricultural applications. J Indian Soc Remote Sens 2008, 36(3), 255-66.

The study was carried out to evaluate the satellite-based hyperspectral data available from Hyperion onboard EO-1 of NASA for agricultural applications. The study was carried out for Daurala block of Meerut district, using data of March 2005. The preliminary data analysis showed that there are 196 usable bands out of a total of 242 bands. Principal component (PC) analysis showed that about 99% of the information explained in 10 PCs. The atmospherically corrected reflectance, derived from satellite data had good agreement with the ground reflectance, observed using handheld spectroradiometer, with r² ranging from 0.85 to 0.98. A set of twenty most usable bands was selected by the criteria of maximum contribution to first five PCs and the band combinations with least inter-band correlations.

6 illus, 3 tables, 30 ref

004612   Malaimani E C;Kumar N R;Akilan A;Abhilash K (NO, National Geophysical Research Institute, Uppal Road, Hyderabad-500 606) : Episodic GPS campaigns at Lakshadweep Islands along the chagos-laccadive ridge to investigate inferred continental flexure in the west of India and the non-rigidity of the oceanic part of the Indian plate. J Indian Geophys Union 2009, 13(1), 1-7.

The Episodic GPS campaigns were initiated at Lakshadweep islands for the first time in India by National Geophysical Research Institute (NGRI) with the objectives of refining the already estimated strain accumulation in the south of Indian peninsula, reaffirming the inferred continental flexure in the south-west of India, and investigating the rigidity of larger oceanic part of the Indian plate. To start with two sites Kavaratti and the northern most island Chetlat were chosen. With the new state-of-the-art GNSS receivers, which could track 30 GPS and 11 GLONASS Satellites with 5°elevation mask, GPS measurements were carried out simultaneously at both Kavaratti and Chetlat for two weeks during March 2007 and repeat measurements were carried out recently in these islands. Very recently the southern most island Minicoy also was included in the experiment design and simultaneous GPS measurements were carried out in both Minicoy and Kavaratti. The acquired data was processed in the latest ITRF 2005 reference Frame. The site coordinates of Kavaratti, Chetlat and Minicoy and also the baseline lengths between Hyderabad and these three sites were estimated in the Global Network Solution. These GNSS receivers, the methodology involved, the results of estimated site coordinates and the baseline lengths between Hyderabad and these islands are discussed in this paper. The estimated baseline length between Hyderabad and Kavaratti is 991, 303.3067 ± 0.0082m. The estimated baseline length between Hyderabad and Chetlat is 892, 216.5594 ± 0.0040m. The estimated baseline length between Hyderabad and Minicoy is 1171, 071.8777 ± 0.0065m. The estimated accuracy of the baseline length is in the range of 4 to 8 mm, which shows the quality of data processing. These studies across a 1,200-km-long "strain gauge" that is optimally oriented almost parallel to the compression seen on the land would enable the understanding whether this is due to the Himalayan collision, or the extension of the Capricorn-India diffuse boundary that could have extended this far north.

4 illus, 15 ref

004611   Khan P K;Ghosh M;Srivastava V K (Applied Geophysics Dep, Indian School of Mines Univ, Dhanbad, Email: pkkhan_india@yahoo.com) : Seismic a-value and the spatial Stress-level variation in northeast India. J Indian Geophys Union 2009, 13(2), 49-62.

The study aims at understanding the variation of stress level vis-a-vis crustal heterogeneity based on seismicity distribution and a-values in the northeast part of India. The study area lies between latitude 24.5° and 27.2°N and longitude 89° and 96°E, and bounded by major thrust sheets of the Himalaya and Indo-Burman Ranges towards north and east. A crustal scale transcurrent Dauki fault demarcates its southern boundary, while the Yamuna lineament and the tail end of the Brahmaputra and Ganga rivers encompass all along the eastern boundary. Regarding seismicity, the area recorded several moderate to large earthquakes during the historical past, and the most damaging well-known 1897 Shillong earthquake was famous for its own kind. In the present study, we have analysed a-values using a comprehensive database recorded by the network jointly run by RRL, Jorhat and NGRI, Hyderabad. A total of 3655 events were used under the present study. Seismicity distribution shows three major clusters of higher concentration over the study area. Contours based on estimated a-values over 240 square grids of dimension 0.6°x0.6° show wide variation. However, the near uniform a-values over specific five zones allowed us for depth probing of a-values. The higher a-values in different layers towards the eastern part are correlated with the reactivation of fractures at lower stress level, whereas the minimum a-values with higher gradient towards the southwestern part of the study area can be associated with higher stress level and linked to the thinner crustal root, and uplifted Moho. The area between the Main Boundary Himalayan Thrust and the Shillong Plateau account higher a-values, and might be indicating brittle failure of the weaker crust at lower stress level around the Tura region. Finally, it may be inferred that the seismicity of the northeast India is due to tectonic adjustment of different geomorphologic features presumably caused by the orogenic processes in the Himalaya and Indo-Burman Ranges.

7 illus, 1 table, 47 ref

004610   Kandpal G C;John B;Joshi K C (Earthquake Geology Div, Geological Survey of India, Northern Region, Aliganj, Lucknow-226 024, Email: gckandpal@yahoo.co.in) : Geotechnical studies in relation to seismic microzonation of union territory of Chandigarh. J Indian Geophys Union 2009, 13(2), 75-83.

The paper highlights the outcome of site response studies undertaken around Union Territory of Chandigarh, based on geotechnical approach. Twenty-four boreholes were drilled down to 30 m depth in order to determine the variation in the geotechnical properties of the geological units present around Chandigarh. Standard Penetration Test (SPT), as per BIS Code, was conducted in all the boreholes for determination of N values of the subsurface geological units at 1 to 3 m intervals. Shear Wave Velocities of the subsurface layers were computed based on the empirical relation. The average shear wave velocity of the sediments down to 30 m depth at different sites around Chandigarh Urban Centre varies from less than 216 to 305 m/s. The predominant frequencies at which the seismic waves are expected to resonate in the soil column of 30 m depth were also computed using frequency-shear wave velocity relationship. Based on the analysis of the geotechnical properties of subsurface soil samples, their disposition with respect to each other and also with ground water table conditions liquefaction potential around Union Territory has also been assessed.

6 illus, 2 tables, 16 ref

004609   Jayaprasad P;Narender B;Pathan S K;Ajai (Forestry Land Use and Photogrammetry Group, RESIPA, Space Applications Centre, ISRO, Ahmedabad-380 015, Email: ajai@sac.isro.gov.in ) : Generation and validation of DEM using SAR interferometry and differential GPS supported by multispectral optical data. J Indian Soc Remote Sens 2008, 36(4), 313-22.

Digital elevation model (DEM) and the derived terrain parameters e.g. contour, slope, aspect, drainage pattern, etc are required for natural resources management, infrastructure planning and disaster management. The present paper aims at generating DEM from ERS tandem pair using interferometric technique supported by differential GPS measurements (DGPS) and multispectral optical data. Validation of DEM has been carried out by DGPS measurements. Ground Control Points (GCP) established by DGPS measurements have been used to georeference the IRS-ID optical data that has finally been co-registered with SAR amplitude image. Optical data, co-registered with ERS - I SAR data has helped in locating the GCP's and check points, precisely, for refinement of DEM and its validation.

7 illus, 2 tables, 14 ref

004608   Farooq S;Ahmad S (Geology Dep, Aligarh Muslim Univ, Aligarh, Email: farooq.amu@gmail.com) : Urban sprawl development around Aligarh city: a study aided by satellite remote sensing and GIS. J Indian Soc Remote Sens 2008, 36(1), 77-88.

Rapid urbanization causes disorganized and unplanned growth of towns and cities. The r pressure of an ever growing population becomes f a burden on the limited civic amenities which are virtually collapsing. Asymmetrical growth of urban centres consumes agricultural land adjacent to these, resulting in lower agricultural productivity. Besides taxing the groundwater resources available for an urban centre, an increase in the paved area severely reduces the groundwater recharge potential, leading to situations which may truly be potential catastrophes. An understanding of the growth dynamics of urban agglomerations is essential for ecologically feasible developmental planning. With almost a third of India's population already having become urban, it is necessary to acquire information on growth patterns of cities and how they impact the living environment. The current trend of spatial urban growth in almost all Indian cities has a haphazard pattern, particularly along the urban-rural fringe. There is an obvious need for continuously monitoring the phenomena of growth, and mapping and analyzing its patterns, since this is of great concern to urban administrators and planners whose concern it is to provide basic amenities and infrastructure for the complex urban environment.

3 illus, 3 tables, 10 ref

004607   Dhorde A;Dhorde A;Gadgil A S (Geography Dep, Pune Univ, Pune-411 007) : Long-term temperature trends at four largest cities of India during the twentieth century. J Indian Geophys Union 2009, 13(2), 85-97.

Investigations have been carried out by climatologists to find a possible link of climate change with anthropogenic activities by studying trends in different climatic parameters, particularly surface air temperature of densely populated cities. The present research aimed at quantifying the change in surface air temperature at India's four most populated cities - Delhi, Kolkata, Mumbai and Chennai. The cities taken up for study have experienced rapid urbanization in the recent past. Therefore, the main objective of the research was to find the impact of urbanization on temperature trends at these cities. Trends in annual and seasonal temperature series were analyzed using linear trend and Mann-Kendall test. From the population trends Less Urbanized Period (LUP) and More Urbanized Period (MUP) were identified. The average population and surface air temperature of these two periods were used to further assess the urbanization effect. Most of the trends showed positive change in temperature with different rates in different seasons. In some cases, the trends showed asymmetry. For example, the maximum temperature at Mumbai during winter and monsoon is significantly increasing whereas minimum temperature shows significant decrease. On the other hand remaining cities recorded significant increase in minimum temperature during winter. The analysis based on LUP and MUP indicates that, on seasonal scale the difference in temperature of these two periods is significant for post-monsoon and winter seasons. Further the relationship indicates a negative change in temperature with increase in population. This indicates that the effect of urbanization is more pronounced during these seasons, as far as warming is concerned. Thus, an inconsistent climatic response to urbanization is observed, at these cities.

5 illus, 3 tables, 51 ref

004606   Dey S;Debbarma C;Sarkar P (Geography and Disaster Management Dep, Tripura Univ, Suryamaninagar-799 130, Email: sudip_geo@rediffmail.com) : Mono-spectral imaging for nanoscale physical character analysis of silica from lake deposition: an experimental study. J Indian Geophys Union 2009, 13(2), 69-74.

Digital microphotography and image analysis is considered as an important tool in sedimentology and mineralogy for the assessment of physical characteristics at micro and nano level. The authors attempted to analyse the physical characteristic like surface condition of a silica grain of a lake deposition layer from mono-spectral imaging at nanometre scale. For that purpose a silica grain was picked up from microphotography of a thin section of sediment layer and lum X lμm base image in greyscale was prepared for operation with sophisticated software. Reflectance capacity of the particle has been considered to measure the topographic condition. Contour plot from the base image was prepared along with a topographic image prepared on the basis of blackbody law. A complete topography map of silica grain was prepared on the basis of two previous plots. A 3D image and four profiles were also consulted for understanding the geometry of the surface of silica. Roughness analysis was also done from the mono-spectral image.

5 illus, 18 ref

004605   Bhatt C M;Litoria P K;Sharma P K (NO, National Remote Sensing Centre, Hyderabad-500 625, Email: combhatt@nrsa.gov.in) : Geomorphic signatures of active tectonics in bist doab interfluvial tract of Punjab, NW India. J Indian Soc Remote Sens 2008, 36(4), 361-73.

Bist Doab interfluvial tract in the northwestern part of Punjab, India, has been investigated for geomorphic signatures of active tectonics using remotely sensed data and geographical information system (GIS). The anomalous river flow, abrupt changes in flow direction, angular drainage, compressed meanders, asymmetry of river bends, high channel sinuosity, abandoned channels, water-logged and marshy areas observed along the courses of Beas and Sutlej rivers and their tributaries indicate tectonically active nature of the terrain. The strong control exercised by the NE-SW and NW-SE trending lineaments on the drainage network is well evident in the form of long straightened slope deviatory courses, definite changes in channel pattern and sharp knee bend turns taken by the seasonal rivulets. The asymmetric and elongated nature of watersheds and straight to curvilinear mountain fronts quantified through morphotectonic analysis are characteristic of tectonically active settings and further corroborate the evidence of active tectonics.

7 illus, 19 ref

004604   Amit Kumar;Sihgh K N;Brij Lal;Singh R D (NO, Institute of Himalayan Bioresource Technology (CSIR), Palampur, Post Box No. 6, Himanchal Pradesh-176 061, Email: amitpnk@yahoo.co.in) : Mapping of apple orchards using remote sensing techniques in cold desert of Himachal Pradesh, India. J Indian Soc Remote Sens 2008, 36(4), 387-92.

The study was conducted to map Apple orchards in dry alpine Spiti region of Indian Himalaya using LISS III satellite image. The barren terrain with sparse woody vegetation helped in classification of apple orchards with 91.3 % accuracy. The orchards were found in 154.6 ha of the study area and are anticipated to expand owing to its economic importance.

4 illus, 13 ref

023471   Vinod Kumar;Bhagat D K U R;Satya Kumar M;Shiv Ganesh (NO, Meteorological Office, Mumbai, Maharashtra) : Impact of low level jet on heavy rainfall events over Mumbai. Mausam 2007, 58(2), 229-40.

Study of 186 (168) cases of heavy (≥65 mm) to very heavy rainfall (≥125 mm) occurred at Santacruz (Colaba) during 21 selected years (normal/deficient All India monsoon years) between 1966 and 2005 suggests that (i) when the low level westerly at 850 hPa is reported ≥ 30 knots by Minicoy/Aminidivi islands or any other station along the west coast of peninsular India from Thiruvananthpuram to Mumbai and (ii) Wind-Temperature-Humidity (WTH) index reaches critical value, very heavy to extremely heavy (≥250 mm) rain occurs over Mumbai and suburbs. Based on above model even unprecedented rainfall of 26 July (944 mm) and very heavy rainfall of 09 September 2005 (223 mm) have been forecast for all domestic flights in the significant weather charts by indicating occasional cb around Mumbai (VABD) 24-30 hours early.

6 illus, 3 tables, 10 ref

023470   Tyagi A (NO, Directorate of Meteorology, Air HQ(VB), New Delhi-110 011) : Thunderstorm climatology over Indian region. Mausam 2007, 58(2), 189-212.

Thunderstorms are primarily short lived mesoscale weather phenomena. Existing synoptic network of part time observatories have limitations in recording all the occurrences of thunderstorms at the observatory and adjoining areas. Inclusion of data from such observatories results in lower frequency of the event and vitiates climatology. Efforts have been made in this study to develop thunderstorm climatology by using quality data of full time current weather (Airport) observatories, class I and selected class II IMD observatories. Since number of full time observatories in most of the sub divisions is few, the study is not able to bring out finer spatial variation of thunderstorm activity with in sub-divisions. Thunderstorm is a high impact severe weather event, which affects all the sectors of the society. Therefore, both from operational and climatological point of view, there is urgent need to establish at least one full time current weather observatory in each district to ensure proper reporting of all thunderstorm occurrences and to build district level thunderstorm climatology in the country.

7 illus, 5 tables, 19 ref

023469   Sarkar P;Singh B (International Div, Geological Survey of India, 27, Jawaharlal Nehru Road, Kolkata-700 016, Email: psarkar_gsi@yahoo.co.in) : Zoning pattern of Jabor rare-metal pegmatite body, Purulia district, West Bengal. Indian Miner 2007, 61(1-2), 45-56.

Documents mineralogical, textural and chemical zoning behaviour within labor rare-metal (RM)-bearing pegmatite of Purulia district, West Bengal. Among the reported five number of rare-metal-bearing pegmatite bodies along ENE-WSW-trending lineament zone within the Chotanagpur Gneissic Complex (CGC) (others are near Beku, Belamu and Khatanga villages), the labor RM pegmatite is the largest one and is fairly exposed on surface. This Precambrian pegmatite body is of LCT type enriched in Rb, Li, Cs rare-earth alkalis and contains minor amount of pollucite (by far the only ore of Cs metal). It is enriched with Rb component in comparison to Li & Cs. Like other LCT pegmatites of the world, it resides within a non-consanguineous granitoid pluton and form anastomising vein and fracture-filling dykes within a granitic host rock. Seven zonal sequences, represented by individual petrographic units were identified on surface outcrop Conspicuous grainsize and textural variations were noted within the pegmatite body from the outer zone to central quartz-rich core. Whole-rock chemistry of individual zonal pegmatite units more or less shows systematic variation of K/Rb from outer zone (=58.4) to inner zone (=28.5). The labor RM pegmatite is of peraluminous nature (P.A index varying from 1.12 to1.92) and possibly evolved from the adjoining composite granite gneiss showing peraluminous chemistry.

7 illus, 2 tables, 19 ref

023468   Saha D;Dhar Y R;Das S (Applied Geology Dep, Indian School of Mines, Dhanbad-826 004) : Delineating ground water potential zones in the marginal alluvial areas of gangetic plain - A case study from Nalanda District, Bihar. Indian Miner 2006, 60(3-4), 181-92.

Ground water resource development in marginal alluvial areas of Mid-Gangetic plain in Bihar bordering the Precambrian highlands to the south, is a challenging task in view of limited thickness (less than 120 m) of the alluvial deposits and predominantly argillaceous nature of the sediments. The present investigation has been carried out in 250 sq km area, bordering the northern fringe of Chhotanagpur Gneissic Complex. The entire water demand of the area is met up from unconsolidated aquifers within the Quaternary alluvial deposits, laid over northerly sloping Precambrian bedrocks. A total of 20 Vertical Electrical Soundings, using Schlumberger configuration have been carried out in the investigated area to delineate and configure the geometry of the aquifers. The litho-units with resistivity values of 15-150 ohm-m were interpreted as sands of various size grades, which are accumulated along the trough of the bedrock forming potential aquifers. Clay and sandy clay show resistivity values of less than 10 ohm-m and 10-15 ohm-m respectively. Geometry of the various litho-units, prepared by geo-electrical section and panel diagram, reveals frequent lateral facies changes over short distances. A clay blanket with variable thickness of 5-58 m, at the top of the succession, puts the aquifer below under semi-confined condition. Promising aquifers identified for ground water development are: (i) a channel-lag deposit in the western part and (ii) sand deposit along the palaeo-channel of the Panchana, an ephemeral river draining along the eastern part of the study area. Pumping tests conducted in two wells indicate transmissivty of the palaeo-channel deposits (<62> 500 m²day) to be much better than that of the channel-lag deposits (320 m^{2/day). Storage coefficient of the aquifers ranges from 4.3x10-3 to 5.3X10-3.}

7 illus, 4 tables, 16 ref

023467   Patil M R;Venkataiah C;Shivaprasad K H (Earth Sciences Dep, Gulbarga University, Sandur, Bellary-853 119) : Recovery of iron values from waste mine dumps by gravity concentration methods. Indian Miner 2007, 61(1-2), 79-84.

Sandur area in Bellary district, Karnataka, is endowed with rich deposits of high-grade iron and manganese ores. Extensive mining has been taking place in this area for several decades now. It is estimated that about 6 million tonnes of material containing iron values ranging from 35-65% Fe is being dumped as waste. The waste dumps in turn are washed away during the rainy season and are permanently lost in the valleys and streams. Though, this loss has been taking place since mining began no attempt has been made to prevent it and to recover iron values from the dumps. These waste dumps contain high amount of alumina and silica and need processing. In the investigation an attempt has been made to recover iron values by gravity methods as they are cheap, efficient and environment friendly. The waste dumps, collected from the different mine sites of VESCO mines of Sandur area, analysed 49-55% Fe, 6-8% AI₂O₃ and 4-7% SiO₂

023466   Meena L R;Mitra A K;Ahmad N;Nath S (NO, India Meteorological Department, New Delhi) : Probability of the formation of fog over New Delhi: a fuzzy logic approach. Mausam 2007, 58(2), 261-5.

3 illus, 2 tables, 7 ref

023465   Lal R P;Giri R K;Sharma R K (NO, India Meteorological Dep, New Delhi) : Integrated water vapour measurement over Dehradun using ground-based GPS and comparison with values obtained from NCEP reanalysis and MODIS data. Mausam 2007, 58(2), 283-6.

4 illus, 2 tables, 15 ref

023464   Lahiri A;Basu P C;Sengupta D (Palaeontology Div, Marine Wing, Geological Survey of India, Bhu-Vijnan Bhawan, DK-6, Sector-II, Salt Lake, Kolkata-700 091, Email: amitabhaa_lahiri@rediffmail.com) : Anomalous distribution of bryozoa on the shelf areas off East Coast of India. Indian Miner 2007, 61(1-2), 25-38.

Study on the bryozoa, contained in the shelf sediments up to a bathymetric depth of 90 m in the Bay of Bengal, has brought out that bryozoans are embedded in both soft and semi-consolidated to consolidated sediments with a few growing into large-sized colonies. The bryozoan forms, dominant in lesser depth extending up to 60 m, are quite often encrusted on benthonic foraminifera. A detailed taxonomy of the bryozoan species reveals the presence of slender and rigid/stout forms belonging to the Cheilostomata and Cyclostomata. In total, thirteen species have been identified. Of these, eight species are slender and five are rigid/stout. The distribution of the bryozan assemblage is controlled by the bathymetry over the shelf region and exhibits that the cheilostome bryozoans outnumber the cyclostome ones. The latter group is represented by five species - Crisia serrata, C. elongata, Idmonea California, Entalophora cylindrica, Hornera jacksonia and H. ramosa - that are scanty in their occurrence within the total assemblage of bryozoans. The cyclostomes in comparison to the cheilostomes show general depletion in the post-Quaternary period. Despite having depth-controlled distribution a few deeper-water species have been found to occur anomalously in shallower depth especially whenever the host sediments are present. This is a typical scenario in storm-prone areas such as off Orissa coast. The reverse scenario is noticed in this area. Besides, presence of slender forms in higher percentage in the domain of rigid/stout forms and vice-versa has also been noticed along shelf areas. This is suggestive of sea-level fluctuations in the past within a long spell of transgression. This has been corroborated by the study of the vertical distribution of bryozoa in four core sediments. Based on above observations and C¹⁴ dating it is presumed that at least 20m level has been raised by water within last 4500 years. An attempt has been made to find out the reasons for the anomalous distribution of different bryozoans on the shelf areas of Bay of Bengal.

3 illus, 2 tables, 38 ref

023463   Karmakar S;Alam M M (NO, Bangladesh Meteorological Dep, Dhaka-1207, Bangladesh) : Tropospheric moisture and its relation with rainfall due to nor's westers in Bangladesh. Mausam 2007, 58(2), 153-60.

Attempts have been made to compute the precipitable water content of the troposphere, weighted average water vapour and to correlate these parameters with different instability indices and also with the next 24-hr rainfall, next 24-hr maximum rainfall and next 24-hr country averaged rainfall in order to predicting rainfall due to nor'westers in Bangladesh. It has been found that the maximum number of nor'westers occur when the precipitable water is 25-45 mm hr^-1 between 1000 and 500 hPa, the maximum frequency being 48 in the range of 35-45 mm hr^-1. The spatial distribution of precipitable water indicates that the maximum precipitable water is concentrated over the area near the places of nor'westers. The specific humidity has been found to increase on the dates of occurrence of nor'westers in Bangladesh on most occasions. Maximum number of nor'westers occurs when the weighted average specific humidity between the surface (1000 hPa) and 500 hPa is 8-12 g kg^-1, the maximum frequency being 43 in the range of 8-10 g kg^-1. The study reveals that nor'westers have been found to occur near or at the eastern end of maximum weighted average specific humidity. It has also been found that nor'westers occur near the point of inter-section of the axes of moist and dry zones. A number of parameters of the troposphere over Dhaka at 0000 UTC on the dates of occurrence of nor'westers such as precipitable water (mm/hr), MSWI, SWI, SWI/TT, (q₁₀₀₀ - q₈₅₀) weighted averaged specific humidity have statistically significant correlations with next 24-hour rainfall at Dhaka, next 24-hour maximum rainfall in Bangladesh and country averaged rainfall. The correlation co-efficients are relatively small and the standard errors of estimates are higher. The small correlation co-efficients are significant because of the large number of data.

7 illus, 1 table, 13 ref

023462   Jenamani R K;Kalsi S R;Hatwar H R;Subramanian S K (NO, Meteorological Office, IGI Airport, New Delhi-110 037) : Another deficient monsoon 2004 - a comparison with drought 2002 and possible causes. Mausam 2007, 58(2), 161-76.

Rainfall over India as a whole during the summer monsoon season of 2004 was deficient with -13% below normal. Earlier in 2002, India has faced another worst situation when large-scale drought occurred and all India rainfall was below -19%. In the study, compared briefly salient observational features of both the monsoons to find out their distinct characteristics. Comparisons show appearance of many similar as well as contrasting features. Though, both seasons were deficient, their dates of onset of monsoon over Kerala were either before or near the normal date. Progress up to central India was also normal in both the seasons. While Indian Summer Monsoon Rainfall (ISMR) during June was good, a few longest stagnation periods during advancing stage in July of both the years made unexpected delay of monsoon in covering entire India. Rainfall of July also suffered the most in both the seasons with a record lowest ISMR in 2002. Not a single depression formed in 2002 while in 2004, their frequency was less than half of normal. Analysis of other large-scale monthly anomalous ocean and atmospheric conditions over Indo-Pacific region including El-Nino conditions confirms that ENSO and Equatorial Indian Ocean Oscillation or EQUINOO have caused drought in July 2002, but not in July 2004. This is because very high typhoon formation and their recurvature with significantly higher than normal convection over northwest Pacific associated with record lowest ISMR in July 2002 in contrast to occurrence of deficient ISMR in July 2004 which was associated with few typhoon formation and less convection. Also in 2002, Indian region was happened to fall exactly under the subsidence branch of Walker circulation with ascending branch over the western Pacific in the season in contrast to 2004, when subsidence was observed to both over large part of western Pacific and adjoining Indian region.

7 illus, 4 tables, 24 ref

023461   Jagadish Singh;Giri R K;Surya Kant (NO, India Meteorological Dep, New Delhi-110 003) : Radiation fog viewed by INSAT - 1D Kalpana Geo - Stationary satellite. Mausam 2007, 58(2), 251-60.

Intense, long-spell and synoptic scale fog over north India has been studied using Very High Resolution Radiometer (V.H.R.R.) visible imageries of INSAT-ID and Kalpana Geo-Stationary satellites. The intensity, coverage and characteristics of fog seen in satellite imageries are found to be in conformity with the ground -based surface meteorological observations. The unusually long spell fog formations have been explained using maximum temperature and relative humidity anomalies of I.G.I Airport, New Delhi, Amousi Airport, Lucknow, Babatpur Airport, Varanasi and Rajasansi Airport, Amritsar. Atmospheric stability of very high order was seen in the lower part of the atmosphere at Delhi creating favourable condition for the formation of intense and long-spell fog. The relation between Wetness Index derived based on Basist study (1998) using 19, 37 and 85 GHz frequency channels of Special Sensor Microwave/Imager (SSM/I) onboard Defense Meteorological Satellite Programme (DMSP) satellite and fog duration were studied.

6 illus, 3 tables, 6 ref

023460   Giri R K;Loe B R;Mukherjee S K;Sharma R K; Rajveer Singh;Devendra Singh (NO, Mount Meteorological Dep, New Delhi) : Inter-comparison of GPS derived PWV with MODIS, NCEP and RS PWV. Mausam 2007, 58(2), 279-82.

2 illus, 10 ref

023459   Durai V R;Roy Bhowmik S K;Hatwar H R (NO, India Meteorological Department, New Delhi-110 003, Email: durai.imd@gmail.com) : Distribution of precipitable water contents over Indian monsoon region. Mausam 2007, 58(2), 241-50.

Investigates the spatial distribution of precipitable water contents over Indian region for the southwest monsoon 2005. The precipitable water contents are derived from the objective analysis field of operational Numerical Weather Prediction system of India Meteorological Department. The study shows that the distribution of PWC is capable to capture large scale features of monsoon precipitation system. Real-time availability of this product is expected to be useful in monitoring and prediction of heavy rainfall events.

5 illus, 6 ref

023458   Deb G K;Chakraborti S;Das S (Geology Dep, Durgapur Government College, Durgapur-713 214, Email: kdgautam@rediffmail.com) : Transition from oxidising to anoxic environment of deposition: clues from the proterozoic microbial dolomites, Pranhita-Godavari valley, South India. Indian Miner 2007, 61(1-2), 1-16.

Because of syn-sedimentary development and records from Archaean to recent formations the biosedimentary structures, particularly stromatolites, may provide important clues to test the hypothesis of uniformitarianism. Despite distinctive morphology and the volume of work carried out on the paleontologic and sedimentologic aspects, significance of these structures is still a debatable issue. However, roles of both biogenic activity and precipitation of carbonates are equally important during growth of these structures. Reports of stromatolites and thrombolite have been made for the first time from a region at the northernmost exposed tip of the northeastern Proterozoic rock belt of the Pranhita-Godavari Valley, where the whole Meso- to Neoproterozoic succession belonging to the Godavari Supergroup is preserved. Morphology of the different organosedimentary structures and the characterªistics of the associated rock horizons, taken together, indicate that the structures with similar geometry grew in like environments. But the organosedimentary structures alone may not be useful for stratiªgraphic correlation. Occurrence of domal and stratiform stromatolites in association with shallowªmarine and deep-water lithologies respectively in a transgressive sequence stands for transition from high-energy oxidising environment to low-energy suboxic or anoxic one, during development of the lower two units of the Godavari Supergroup. After exposure to the level of erosion of the said units, re-appearance of the do mal stromatolite in the next higher unit suggests repetition of the oxidising condition. The lithologic-cum-organosedimentary association of the region, in turn, stands for control of the relative sea-level change.

10 illus, 1 table, 39 ref

023457   Das H P;Kashyapi A (NO, India Meteorological Dep, une-411 005) : Forecasting of minimum temperature for agrometeorological advisory services (AAS). Mausam 2007, 58(2), 265-73.

1 illus, 5 tables, 6 ref

023456   Das D K (NO, , , Email: dkdas_2006@rediffmail.com) : Analytical methodologies and their applications in geoanalysis. Indian Miner 2007, 61(1-2), 57-78.

During the last 50 years, there has been a phenomenal advancement in the field of analytical instrumentation that permits determination of most elements in the Periodic Table down to ppb / ppt levels of concentrations. This unique development has facilitated the geoscientists in elucidating nature of primary and secondary halos associated with mineral deposits as well as to locate deeply buried ore deposits. Besides mineral investigations in the fields of base metals. REEs (Rare Earth Elements), PGEs (Platinum Group of Elements), HFSEs (High Field Strength Elements). straªtegic elements etc., the latest state-of-the-art analytical instruments are being widely used in geoªchemical mapping. environmental studies, agriculture, industries, nuclear chemistry, bio-geochemªistry, clinical investigations, medical geology also in many other diverse fields. Briefly describes the gradual development of analytiªcal instrumentations that have been confidently utilised in different geo-scientific investigations.

10 tables, 100 ref

023455   Chattopadhyay N;Mukhopadhyay D;Bhattacharyya T (Geological Sciences Dep, Jadavpur Univ, Kolkata-700 032, Email: neelakdg@gmail.com) : Primary and secondary features in the Anasagar gneiss near Ajmer and their implication on the evolution of the Proterozoic South Delhi fold belt, Central Rajasthan. Indian Miner 2006, 60(3-4), 105-18.

The Anasagar Gneiss - a typical megacryst-bearing granite gneiss - was syntectonically emplaced during D₁ as a sheet-like body within a supracrustal sequence dominated by quartzite, with subordinate mica schist and discontinuous amphibolite bands. At places, the microcline megacrysts constitute up to 35% by volume of the rocks. The megacrysts are products of slow cooling during late magmatic crystallisation. Parallel alignment of euhedral megacrysts and alternation of megacryst-rich and megacryst-free bands represent magmatic features. The megacrysts are in general recrystallised to aggregates of smaller grains, often retaining their crystal outline. Post-crystallisation deformation has converted the megacrysts to lensoid augen-like objects or thin lenticular bands parallel to the foliation or has disrupted them into fragments. Close to the contact, strong deformation has converted the megacrysts into thin elongated streaks giving rise to a fine-grained streaky banded gneiss. The structural and textural features indicate that the foliation in the gneiss started as a magmatic structure and subsequently acquired the character of a deformational (D₁) planar fabric. This foliation is folded by D₂ and D₃ folds which are also present in the supracrustal envelope. The new information suggests that the Anasagar Granite Gneiss along with its enveloping supracrustals are Pre-Delhi in age, and the D₁ deformation was also Pre-Delhi. The easterly directed movement giving rise to asymmetrical east-vergent folds (D₂), followed by late-stage coaxial upright folds (D₃ ) belong to the South Delhi orogeny.

16 illus, 2 tables, 29 ref

023454   Charan Singh;Bandyopadhyay B K (NO, India Meteorological Department, New Delhi) : Behavior of tropical cyclones along the east coast of India prior to landfall. Mausam 2007, 58(2), 273-9.

7 illus, 3 tables, 3 ref