019089   Sujaya K;Heera Singh R;Rao B C S; Sathyanarayana M (Servo Systems Lab, Satellite Data Reception Systems, NRSC, Hyderabad, Email: sujaya3030@gmail.com) : Current control strategy for BLDC drive in satellite ground station. Int J appl Engng Res Dindigul 2011, 2(1), 1-9.

New current control strategy is implemented to control the BLDC motor drive based on a common DC signal. Current sensors are used to sense the motor currents, these currents are compared with reference currents to get required error for controlling BLDC drive. This error is compensated in PI controller and is compared with the triangular wave to produce the desired pulses. In this way the amplitude of the signal is controlled in a closed-loop manner by sensing the output currents and comparing with reference currents. The instant at which it has to be given is found by using the position sensors. This strategy is very simple, dynamic in behavior, easy and flexible to control & implement. The major advantage being one signal is sufficient to control the three phase currents of the motor. The program selected for implementation is SimPowerSystems/ Matlab to show the dynamic characteristics, flexibility & simplicity of drive system. It has been compared with the conventional techniques and excellent results have been found.

10 illus, 11 ref

019088   Sudhanandh V S;Udayakumar P;Ouseph P P; Amaldev S;Narendra Babu K (Coastal Ocean Monitoring and Prediction System (COMPAS), Ministry of Earth Science Unit, Centre for Earth Science Studies, Thiruvananthapuram-695 031, Email: sudhanandvs@gmail.com ) : Dispersion and accumulation trend of heavy metals in coastal and estuarine sediments and its textura characteristics, a case study in India. J hum Ecol 2011, 36(2), 85-90.

This study evaluated the persistence of heavy metals, cadmium (Cd), lead (Pb) and mercury (Hg) in surficial marine sediments and their relationship with textural characteristics. Furthermore, heavy metal distribution was studied against organic carbon concentration within the sediments. Our results suggest that Cochin estuary is highly polluted in the case of all heavy metals (Pb of 29.48 ± 4.37 μg/g, Cd of 0.21 ± 0.17 μg/g and Hg of 0.17 ± 0.15 μg/g). All the studied trace elements showed negative correlation with sand particles. However, significant positive correlations were observed between lead and mercury with silt and organic carbon (P <60> 0.01), presumably metal accumulation increases with decrease in sediment grain size. The concentrations of the trace elements reported in this work are useful as reliable baselines and can be used for comparison in future studies.

5 illus, 3 tables, 13 ref

019087   Sivakumar V;Biju C;Deshmukh B (Geomatics Solutions Development Group, Centre for Development of Advanced Computing, Pune-411 007, Email: vsivakumar@cdac.in) : Hypsometric analysis of Varattaru river basin of Harur taluk, Dharmapuri districts, Tamil Nadu, India using geomatics technology. Int J Geomatics Geosci 2011, 2(1), 241-7.

Hypsometric analysis describes the distribution of horizontal cross-sectional area of river morphology with respect to elevation (area-altitude analysis). Morphology of a river basin plays primary role in the dynamics of surface and subsurface water runoff generation. It is also an essential tool to measure and represent the form of a watershed and its evolution. Aim of the study is to carry out the Hypsometric analysis of Varattaru river basin of Harur taluk, Dharmapuri district, Tamilnadu using remote sensing and GIS technologies. Hypsometric data were derived and analyzed for each of the divided sub zone of Varattaru river basin from the 30 meter ASTER DEM. It was found that high-medium hypsometric integrals/elevation-relief ratios indicating a youthful to mature stage landscape, medium to complex denudational processes, the linear river morphological changes of this river basin and remote sensing data and open source tools it becomes less tedious to make hypsometric integrals and curves. Emphasizes the rainwater harvest practices and management for the watershed at suitable locations for controlling further erosion, reducing the runoff and increases the groundwater potential.

6 illus, 7 ref

019086   Sitender;Rajeshwari (Geography Dep, Kurukshetra University, Kurukshetra-136 119, Email: sitendar@gmail.com) : Delineation of groundwater potential zones in Mewat district, Haryana, India. Int J Geomatics Geosci 2011, 2(1), 270-81.

Groundwater is one of the very precious natural resource of earth that sustains all human activities. It is essential not only for sustenance of the human life but also for the economic and social progress of a region. The study is an attempt to delineate groundwater potential zones in a southern district of Haryana, named Mewat. Survey of India toposheets, satellite imageries and some other collateral data is used for the preparation of thematic layers like geology, geomorphology, percent slope, drainage density, lineament density and land use/land cover of the study area. Multi-criteria evaluation technique is used to integrate all the thematic layers. Individual themes and their corresponding categories are assigned a knowledge base ranking from 1 to 6 depending on their suitability to hold groundwater and their weightage are calculated. Using rater calculator tool in Arc GIS software, all thematic maps are integrated to produce a composite groundwater potential map of the study area. This map was further classified into five categories which represents very poor to excellent potential zones. The study reveals that paleo channels and alluvial plain are the geomorphological features with excellent potential for groundwater occurrence followed by aeolian plain. The residual hills, structural hills and linear ridges due to high slope and absence of primary porosity lies in the very poor to poor potential zones.

6 illus, 1 table, 14 ref

019085   Singh O (Geography Dep, Kurukshetra Univ, Kurukshetra-136 119, Email: ovsome@yahoo.com) : Rainfall, runoff and sediment transport from a forested lesser himalayan watershed in Himachal Pradesh. J Indian Geophys Union 2011, 15(4), 207-20.

Sediment transfer from continents to oceans via rivers is one of the most important processes. The amount of sediment transported from a watershed system is an indicator of the rate of erosion or the soil loss. In the present study, the long-term annual, seasonal, monthly and diurnal variations in sediment transport have been studied at the outlet (concentration point) of Tirthan watershed using the monitored data during 1981-2004. The sediment transport at the outlet of watershed is a function of rainfall and runoff occurring over the watershed area. A temporal and spatial variation in the amount of rainfall and runoff clearly exhibits annual, seasonal, monthly and diurnal variation in the sediment generation response behaviour. The higher concentration of rainfall depths exceeding 5 mm or more with significant variability could result in generation of more sediment fluxes. Both sediment concentration and load have been found to be the highest in the month of July followed by August and nearly 67% of the total sediment load has been transported in these two months. The peak of sediment load in July and August indicates that materials weathered during the dry season get mobilized during this period. Sediment load for the entire study period is computed as 454 t km^-2 yr^-1. Sediment yield from the watershed was lower as compared to the average sedimentation rate of the north Indian reservoirs. Availability of good forest cover (56%) within the watershed system may be attributed to low sediment transport rates from this watershed. The lower sedimentation rate from the watershed will enhance the operational efficiency of hydro-power projects to be built or already constructed in the Tirthan watershed system.

8 illus, 5 tables, 36 ref

019084   Sharifian H;Bargi K;Mohamad Ahangar; Safarnezhad M (Civil Engineering Dep, College of Engineering, University of Tehran, Tehran, Iran, Email: hesam_sharifian@ut.ac.ir) : Important factors of quay walls deformation under seismic loading. Int J appl Engng Res Dindigul 2011, 2(1), 270-7.

Harbor structures, such as quay walls, bridges, break waters, dolphins and etc. are divided into retaining walls and shallow and deep foundations due to geotechnical aspects. Gravity type foundations such as caissons may be affected from many geotechnical factors like soil properties and liquefaction sensitivity on earthquake damages. ABAQUS is used to determine the mechanism of damage of 1995 Hyogoken - Nanbu earthquake on the caisson quay wall. In addition, the effects of geometry of quay wall, properties of soil etc. on quay wall evaluated. As it was seen in Kobe, this numerical modeling is also offers 3 meters displacement in average for caisson walls. It shows that the most influential factors are permeability, friction angle and dynamic properties of the backfill.

4 illus, 2 tables, 7 ref

019083   Senthi Vadivel A S;Bhupatthi R (NO, Indian Society for Training and Development, Hyderabad Chapter, Hyderabad, Andhra Pradesh, Email: senthilvadivel@gmail.com) : Overview of GSI mission in disaster management using geoinformatics. Int J Geomatics Geosci 2011, 2(1), 57-70.

About 60% of area in India is prone to various natural hazards. The frequent natural hazards in the late 20th century, have forced some of the Organisations under Government of India to plan for risk reduction by early warning system and to mitigate the post disaster effects. Geological Survey of India (GSI) is one of the oldest survey organizations, which is one among the government organisations engaged in the study of natural hazard in India for more than last 125 years apart from its main activity of mineral exploration. From the year 2004, GSI being the convener of the Technical Committee of the Ministry of Home Affairs (MHA) prepares Landslide Hazard Zonation Mapping as these base maps depict the ground reality in disaster prone areas and provide meaningful insights into various decisions making. Pesents the futuristic plan of GSI from middle of XI plan to XIII plan using 3D GIS, RDBMS, 3D processing technology, etc. in preparation of National _ Dimension (3/4D) geospatial data with special reference to natural hazard management, particularly integrated thematic mapping after geomorphological mapping, scale as per site specific requirements based on the vulnerability, for the purpose of Natural Hazards Processes and Geo-Environmental Hazard, etc., Focuses on the relevant portion of Mission III of the GSI on Geoinformatics, Mission IV of the GSI on natural hazards viz., landslide, earthquake, flood and volcanoes and Mission V of the GSI on Training and Capacity Building. The authors conclude that Geoinformatics as a tool of Intelligent Decision Support System, Expert system and Earth Observation System, can play a major role in Disaster Management and can sustainably contribute towards nation's sustainable development.

1 table, 20 ref

019082   Selvam G;Banukumar K;Srinivasan D;Selvakumar R;Alaguraja P (Geology Dep, National College, Tiruchirappalli-620 001, Email: geoselvar@gmail.com) : Identification of ground water potential zone in hard rock terrain - a case study from parts of Manapparai block Tamil Nadu using remote sensing and GIS techniques. Int J Adv Remote Sens GIS 2012, 1(1), 9-18.

Freshwater is a scarce resource with partial existence above and predominantly beneath the surface. Owing to population explosion and improper management, the resource is depleting drastically and is accomplished by extensive mining of groundwater. But the occurrence of groundwater that too in hard rock terrain still remains enigmatic. The movement and storage of groundwater is controlled by various terrain parameters. Hence geoscientists were employing various techniques to explore the potential zone amongst Multi-Criteria Evaluation (MCE) technique seems to be more precise in demarcating the potential zone. Remote sensing and geographic information system (GIS) has proven as effective tools in mapping and modeling terrain features. In this context, an attempt has been made to identify groundwater potential zone in parts of Manapparai block, central Tamil Nadu, India using Remote Sensing and GIS. The study area chiefly comprises of crystalline gneissic rock of Archaean age. Thematic layers were generated on geomorphology, landuse/land cover, lineament density etc. Based on the potentiality to groundwater, weights were assigned to individual themes and ranks to features in each theme and by multiplying both, feature Scores were derived. Themes were converted into raster datasets and added using raster calculator. The final integrated map was regrouped into five classes of groundwater potential zones as very good, good, moderate, moderately poor and poor.

3 illus, 1 table, 45 ref

019081   Sarma A A L N;Sivaram B (Meteorology & Oceanography Dep, Andhra Univ, Visakhapatnam-530 003, Email: aalnsarma_met@rediffmail.com) : Spatiotemporal distribution of weekly hydroclimatic potentialities of India - monsoon period. J Indian Geophys Union 2011, 15(1), 9-24.

Hydroclimatic potentialities such as precipitation, potential evapotranspiration, actual evapotranspiration, water surplus, water deficit, soil moisture storage along with the indices such as humidity, aridity and moisture, soil wetness and soil moisture adequacy over India for the monsoon period on a weekly basis are reported by following the revised water balance model. The paper address the occurrence of varied degrees of drought and humid events for the selected stations drawn from the climate spectrum along with All India during the monsoon period and are of vital importance for crop scheduling especially in the context of increased climate variability.

11 illus, 5 tables, 23 ref

019080   Sankar S;Prabaharan S;Lakshumanan C; Ramalingam M (NO, Institute of Remote Sensing, Anna University, Chennai-600 025, Email: haripraba@gmail.com) : Remote sensing and GIS based tectonic evolution studies in parts of Dindigul and Tiruchirappalli district, Tamil Nadu. Int J Geomatics Geosci 2011, 2(1), 157-63.

Detailed and critical observations of the earth and its changing faces have become very essential now a days so as to need to clear understanding on the natural resources of the planet earth, modern geologic process and their control over natural resources, environment and natural disasters. In really geo-system anomalies clearly indicate that active tectonic is going on. Lineaments, geomorphology, drainage and structural trend lines using the remote sensing tools and find out the various geosystem parameters and also identifying of geosystem anomalies. The geosystem dynamics plays a major role in the earth system activities. It is a major criteria in the every study such as mineral, groundwater exploration etc.

2 illus, 12 ref

019079   Samuel Selvaraj R;Uma R (Physics Dep, Presidency College, Chennai-600 005, Email: umajeel@gmail.com) : Geomagnetic disturbances and cyclonic activity over the north indian ocean during 22<. J Indian Geophys Union 2011, 15(2), 95-9.

Tropical Cyclone activities over the North Indian Ocean (comprising Bay of Bengal and Arabian Sea) constitute one of the major natural disasters of our country. To understand the Tropical Cyclonic activities, estimations of their frequencies are necessary. In this study the number of Geomagnetic Storms (Sudden and Gradual type) during 22nd solar cycle and Cyclonic Activity includes Depression, Cyclonic Storm and Severe Cyclonic Storm over the North Indian Ocean has been analysed using Spearman Rank Correlation technique. A positive correlation is found in both cases. When compared to Sudden or Gradual type of Geomagnetic Storms, the Gradual type of Geomagnetic Storms increases the Cyclonic Activity over the North Indian Ocean during 22nd solar cycle.

2 illus, 2 table, 12 ref

019078   Rawat M;Sharma H;Singh M;Kedareswarudu U; Singh R P (NO, Petroleum & Energy Studies Univ, Energy Acres, Bidholi, Dehradoon, Uttarakhand, Email: kedareswarudu@yahoo.com) : Evaluation of aquifer parameters and groundwater quality in doon valley, Uttarakhand. J Indian Geophys Union 2011, 15(3), 125-34.

Doon valley forms part of Dehradun District, Uttarakhand in the Himalayan Mountain Belt. Doon valley area is drained by the mighty rivers, Ganga, Yamuna and their tributaries prominent of which are Asan, Tons, Rispana and Song rivers. Though the area is bestowed with plenty of surface water resource, the major drinking and irrigation requirements of the valley are met through groundwater. Therefore, it becomes imperative to know the scientific attributes of the ground water bearing formations so that the ground water may be developed and managed in an objective and controlled manner. There are two aquifers in the valley, shallow aquifer under unconfined conditions and deeper with confined conditions. Pumping tests are carried out, one in each of the aquifers, to estimate the aquifer parameters and well characteristics. These values infer that these aquifers are with high potential. Groundwater quality is also analyzed through hydrochemical data obtained from 20 samples covering the area. Ninety five percent of the samples fall in field 5 of the Richard's diagram where alkaline earths dominate over the alkalies and weak acids exceed the strong acids. The data suggests that the groundwater in Doon Valley is potable and suitable for domestic and irrigation purposes.

8 illus, 2 tbales, 10 ref

019077   Rao N B;Srinivas N;Rao B S P;Jai Sankar G;Rao V V;Amminedu E;Venkateswarlu N;Rajesh N;Rao P K;Satya Kumar M (Geo-Engineering Dep, College of Engineering, Andhra Univ, Visakhapatnam-530 003) : Study on nagarjunasagar to somasila link canal alignment and its impact on environment using IRS-P6, AWiFS data. J Indian Geophys Union 2011, 15(2), 113-22.

Rainfall in the country is extremely erratic and unevenly distributed. A huge amount of water is wasted into the sea as run-off whenever there is heavy precipitation due to monsoon/cyclones. Run-off/surplus water can be harvested through the proposed linking of river basins envisaged by National Water Development Agency (NWDA). The NWDA suggested three link canals from Krishna River to Pennar River to harvest the surplus water as well as the transferred surplus from Godavari. The present study is confined to Nagarjunasagar to Somasila link canal, which is one of them, is 341 km length. The study includes 10 km buffer area on either side of the alignment and the proposed command area 3252 sq km in Prakasam district. The total study area is 9,367.5 sq km. IRS-P6 AWiFS data of March 2009 is utilized for the real time study. The study revealed that 162 villages, which are fallen in the alignment, are to be rehabilitated while executing the canal. About 1202 villages will be benefitted by way of drinking water/groundwater recharge and additional irrigation source. The environmental impact on forest, agriculture land, roads and drainage are discussed in the study. Remote sensing study revealed that a large extent of area is under the class of wasteland (229,483 ha) in the study area. Hence, this canal water is extremely useful for the mankind and at the same time mitigating floods in the donor basin (Krishna basin).

5 illus, 3 tables, 19 ref

019076   Rao B S P;Pernaidu P;Amminedu E;Rao T V; Satyakumar M;Sathi Devi K;Rao P J;Srinivas N;Rao N B (Geo-engineering Dep, College of Engineering, Andhra Univ, Visakhapatnam-530 003, Email: bosukonda@gmail.com) : Run-off and flood estimation in krishna river delta using remote sensing & GIS. J Indian Geophys Union 2011, 15(2), 101-11.

Run-off and flood estimation is attempted for cyclone induced rainfall in this study using real time data. A cyclone has potentially destructive characteristics such as strong winds, heavy rains and waves induced from storm surges as exemplified by the severe storm that crossed the Bay of Bengal coast in the Krishna delta region, 40 km south of Machilipatnam on 9th May 1990 is the subject of present investigation. Flood mapping and hazard zonation are indispensable for a real time study of floods and is only possible through remote sensing and GIS. An attempt is made to estimate run-off and flood with real time information derived from remote sensing as conventional approach does not give accurate estimates nor is fast. Soil Conservation Society (SCS) model is adopted to estimate storm run-off. Weighted Curve Number (CN) of the Krishna river basin (India) is determined as 72.4 based upon combinations of land use, soil type and hydrologic features. Flood estimation in the Krishna river basin using SCS Run-off model is estimated at 989.74 MCM during rainfall of 11 days from 5th may to 15th May 1990. The method of weighted curve number is easier, less time consuming and accurate with real time data, hence is applicable for the assessment of flood due to cyclone elsewhere.

6 illus, 6 tables, 26 ref

019075   Rajesh Kumar V;Benedict P (Civil Engineering Dep, Parisutham Institute of Technology and Science, Thanjavur, Tamil Nadu, Email: rajeeii@yahoo.com) : Development of route information system for ambulance services using GPS and GIS - a study on Thanjavur town. Int J Geomatics Geosci 2011, 2(1), 147-56.

Improving technologies in this modern world proportion the carelessness of the people in many ways, highlighting the traffic system. The public or ambulance service does not know the nearby location and the level of services provided by the hospitals. The lack of such information may cause several causalities. Hence, the research question arises in a way to answer how to transport patients in the safest and convenient manner. So, ambulance routing and finding feasible path for safe transportation are the probable necessities to avoid traffic and path constraints. The ambulance service, the exemplary gift showered by the nature, to save life, is found handicapped in the present existing condition. Since the urbanization processes hats off in each and every part of the world, the distribution of the shelter for the mankind is very complex. This reflects with the inability of the ambulance driver to reach the spot on time. To avoid these negative conditions, GPS & GIS technologies are used to maintain the objectives of the ambulance system, as presented in this article. A pilot study has been carried out with the road routes, of about 80 km in the enclosed area that extends between 10°44'15. 266''and 10°48'6. 458''N latitudes and 79°5'57. 656''and 79°9'8. 669''E longitudes of thanjavur town, a high population density region extending its suburban limits day by day. The base map of the road routes in the study area was prepared from google earth supplemented with ground truth information. The spatial data for geo-referencing the prepared map was acquired by a handheld GPS (Trimble). The GIS software was used (ArcGIS 8.1.1 version) in linking the spatial data with attributes like ambulance spots and other places to reach, the ambulance is proposed to move and length of the roads (for drivers to reach the destination on time). Subsequently, training has been given to the ambulance driver on the approach developed and the drivers applauded the same.

5 illus, 9 ref

019074   Raja Kumar T J;Balasubramanian A;Kumar R S; Dushiyanthan C;Karthikeyan K;Thiruneelakandan B;Davidraju D;Manoharan K (Earth Sciences Dep, Annamalai Univ, Annamalai Nagar-608 002, Email: tjeyavel@rediffmail.com) : Delineation and evaluation of groundwater potential zones using electrical resistivity survey and aquifer performance test in uppodai of chittar- uppodai water shed, tambaraparani river basin, Tirunelveli-Thoothukudi districts, Tamil Nadu. J Indian Geophys Union 2011, 15(2), 85-94.

Geophysical Resistivity survey and aquifer performance test were conducted to delineate groundwater potential zones of Uppodai, Chittar - Uppodai water shed, Tambaraparani River Basin, Tirunelveli and Thoothukudi Districts. It is located between the North latitude of 8° 52' to 9° 10' and the east Longitude of 77° 35'to 77° 55'. The area is constrained with crystalline rocks of Achaean age consisting of gneisses, charnockites, granites, basic and acidic intrusives. In order to understand the subsurface lithology, 12 Vertical Electrical Soundings (VES) were carried out. The field resistivity data have been interpreted using RESIST 87 software. The resistivity value and subsurface layer thickness for the first layer varied from 18 Ωm to 122 Om and 8.3m to 41.4 m. The depth to basement is observed at a shallow depth of 10.m in the northwestern part and more than 50m in southern part of the study area. For understanding the aquifer characteristics 5 aquifer performance tests were conducted in the study area. The transmissivity and storage coefficient values computed from Jacob's straight line method varied from 43.6525 msq/d to 167.4367 msq/d and 0.00001 to 0.00163 respectively. The optimum yield and Recovery rate have been obtained as 3.0 m3/d to 100 m3/d and 34.0 hours to 379.3 hours respectively. The interpreted result of VES synchronizes with aquifer characteristics. The present study has proved the use of resistivity method and aquifer test as excellent tools to delineate groundwater potential zones and subsurface lithology.

8 illus, 2 tables, 5 ref

019073   Raghu V;Reddy K M (NO, A.P. State Remote Sensing Applications Centre (APSRAC) 8th Floor 'B' a, Swarnajayanthi Complex, Besides Maithrivanam, Ameerpet, Hyderabad-500 038, Email: raghuvangeepuram@rediffmail.com) : Hydrogeomorphological mapping at village level using high resolution satellite data and impact analysis of check dams in part of akuledu vanka watershed, Anantapur district, Andhra Pradesh. J Indian Geophys Union 2011, 15(1), 1-8.

Anantapur District is a hot and arid District, falls in rain shadow zone with a very low annual rainfall of 520mm. The recurrence of drought increased considerably and unless collective measures are initiated on a permanent basis the situation will become grim in future. Akuledu Vanka watershed in Anantapur District is selected to demonstrate the capability of high resolution satellite data in ground water mapping at village level. This watershed is located in Survey of India toposheet Nos. 57F/5 and F/9. This watershed with an area of about 54 sq.km is underlined by hornblende-biotite gneiss and metabasalt traversed by dolerite dykes. Hydrogeomorphological mapping was carried out on 1:10,000 scale using IRS-P6 LISS-IV satellite data. The satellite data facilitates to update the extent of built-up area, road and drainage network. Further, the revenue villages enclosed in the watershed are digitized, mosaiced and superimposed on hydrogeomorphology map. This helps to give site specific recommendation on ground water prospects survey number wise i.e. for individual farmers. In addition, the impact analysis of check dams constructed in the watershed is also discussed. Studies showed that after construction of check dams the water levels in wells increased, abandoned wells got rejuvenated, new bore wells came up resulting increased irrigated area.

4 illus, 15 ref

019072   Prasad N B N (NO, Centre for Water Resources Development and Management, Kozhikode-673 571, Email: nbnprasad@hotmail.com) : Geophysical investigation for groundwater exploration in lakshadweep islands. J Indian Geophys Union 2011, 15(4), 221-7.

Main problems experienced by the islanders of Lakshadweep is associated with the availability of fresh water for drinking purpose. The scarcity of fresh water is due to the peculiar hydrologic, geologic, geomorphic and demographic features. Proper understanding of the groundwater condition, in terms of availability distribution and quality, is very important to meet the increasing demand and also to formulate future planning and development of water resources. However there is very limited data/information available with regard to hydrogeological aspects of Lakshadweep. It is in this context; this study has been carried out. Geophysical investigation, using electrical resistivity method, is employed to locate potential zones of ground water in Andrott Island, one of the 10 inhabited islands in Lakshadweep. The data has been interpreted with the help of computer-aided techniques and presented in the form of spatial maps. The details of sub-surface lithology, as observed from the nearby existing dugwells and the water quality of the surrounding wells have also been considered during the interpretation of resistivity data.

3 illus, 1 table, 8 ref

019071   Pinak R;Bapat G (NO, Centre for Development of Advance Computing, Pune University Campus, Ganeshkhind Road, Pune-411 005, Email: pinakr@gmail.com) : Estimation of power generation from solid waste generated in sub-urban area using spatial techniques: a case study for Pune city, India. Int J Geomatics Geosci 2011, 2(1), 179-87.

Eelectricity sector in India supplies the world's 6th largest energy consumer, accounting for 3.4% of global energy consumption by more than 17% of global population. About 65.34% of the electricity consumed in India is generated by thermal, 21.53% by hydroelectric power plants, 2.70% by nuclear power plants and 10.42% by Renewable Energy Sources. More than 50% of India's commercial energy demand is met through the country's vast coal reserves. The country has also invested heavily in recent years in renewable energy utilization, especially wind energy. Four major economic and social drivers characterize the energy policy of India: a rapidly growing economy, increasing household incomes, limited domestic reserves of fossil fuels and the adverse impact on the environment of rapid development in urban and regional areas. Meanwhile, the rural areas are struggling with a chronically tight supply of electrical power. In order to properly manage the changing conditions, knowledge and estimation of the available resources and applying their relation with the population is of utmost importance. Deals with extraction of such information with the help of spatial techniques. Also deals with estimation of the amount of solid waste generated by a part of the Pune city using spatial techniques.

6 illus, 4 tables, 6 ref

019070   Pareta K;Pareta U (NRM and RS/GIS Div, Spatial Decisions, B-30 Kailash Colony, New Delhi-110 048, Email: kuldeep.p@spatialdecisions.in) : Quantitative morphometric analysis of a watershed of Yamuna basin, India using ASTER (DEM) data and GIS. Int J Geomatics Geosci 2011, 2(1), 248-69.

Studies the detail morphometric characteristics of Karawan watershed in Dhasan basin, which itself is part of the mega Yamuna basin in Sagar district, Madhya Pradesh. For detailed study, used ASTER data for preparing digital elevation model (DEM), and geographical information system (GIS) was used in evaluation of linear, areal and relief aspects of morphometric parameters. Watershed boundary, flow accumulation, flow direction, flow length, stream ordering have been prepared using ArcHydro Tool; and contour, slope-aspect, hillshade have been prepared using Surface Tool in ArcGIS-10 software, and ASTER (DEM). Different thematic maps i.e. drainage density, slope, relief, superimposed profile, and longitudinal profiles have been prepared by using ArcGIS software. Authors have computed more than 85 morphometric parameter of all aspects. Based on all morphometric parameters analysis; that the erosional development of the area by the streams has progressed well beyond maturity and that lithology has had an influence in the drainage development. These studies are very useful for planning rainwater harvesting and watershed management.

8 illus, 5 tables, 33 ref

019069   Mukherjee S (Earth Sciences Dep, Indian Institute of Technology, Bombay, Powai, Mumbai-400 076, Email: soumyajitm@gmail.com) : Estimating the viscosity of rock bodies- a comparison between the hormuz- and the namakdan salt diapirs in the persian gulf, and the Tso morari gneiss dome in the Himalaya. J Indian Geophys Union 2011, 15(3), 161-70.

Based on known extrusion rates, the viscosities of me Hormuz and the Namakdan salt diapirs in the Persian Gulf were estimated to be between l.l5x10¹⁷ and 8.75xl0²⁰ Pa s, and the Tso Morari gneiss dome in the Himalaya to be ≤ 10²² Pa s. The idea behind doing these exercises was that the deduced parameters would help us in building scaled analogue model of tectonics of these areas. Neglecting any gravity spreading, erosion and the geothermal gradient, these diapirs and domes were assumed to be incompressible Newtonian viscous fluids, which extruded at rates of few mm per year through channels of uniform elliptical or circular cross-sections driven by buoyant push arising from minor difference in density of the rocks at the bottom. However, while the salt diapirs rose ≤ 10 km through vertical channels for 10⁴ yrs, the gneiss dome extruded hundreds or even thousands of km along a channel that plunged between 7° and 62° (maximum variation allowed by previous workers in their models) for 53 Ma covering hundreds or even thousands of km along the channel. Starting from the Poisson equation, the velocity profile of the salt diapirs are deduced to be time dependent and free from any overburden rocks, whereas that the velocity profile for the Tso Morari dome was independent to time and a plug of multi-lithology tried to prevent its extrusion were considered.

6 illus, 5 tbales, 22 ref

019068   Mbarga T N;Meying A;Bisso D;Layu D Y;Sharma K K;Dicoum E M (Physics Dep, Advanced Teacher's Training College, Yaounde I Univ, P.O. Box 47, Yaounde Cameroun, Email: theopndougsa@gmail.com) : Audiomagnetotellurics (A.M.T.) soundings based on the bostick approach and evidence of tectonic features along the northern edge of the congo craton, in the messamena/abong-mbang area (cameroon). J Indian Geophys Union 2011, 15(3), 145-58.

Audio-Magnetotelluric (A.M.T) study is carried out in the Messamena/Abong-Mbang area in Cameroon. It consists of two measurement profiles S-N. The A.M.T data sets are collected using a resistivity meter with frequencies ranging from 4.1 Hz to 2300 Hz. The frequency range used has permitted to reach some important depths because of high resistivity values of the metamorphic rocks. A 1D linearized inversion and 2D modelling of data led to attain a granitic basement at 9 km on one hand, and to put in evidence an important buried fault structure at Abong-Mbang in another hand. From a 2D modelling of pseudo-sections of resistivity and phase, a system of folds has been discovered at Messamena. The tectonic structures put in evidence in the Messamena/Abong-Mbang area are perfectly linked to the collision between the Pan-African Belt and the Congo Craton. The pseudo sections of phase for the two profiles permitted to propose two geological models of rock layers distribution.

9 illus, 1 table, 34 ref

019067   Manisha;Dinesh Kumar;Teotia S S (Geophysics Dep, Kurukshetra Univ, Kurukshetra-136 119, Email: san553@yahoo.co.in) : Seismic hazard based on simulated accelerograms due to moderate/strong earthquakes in national capital (Delhi) region. J Indian Geophys Union 2011, 15(2), 77-83.

National Capital Region (NCR) of India lies in the geological realm of the Peninsular India and is about 200 km from the India plate boundary (Himalaya). The NCR may be affected by a great earthquake in Central Seismic Gap (CSG) of Himalaya and/or by moderate/strong earthquake in NCR. The occurrence of moderate/strong earthquake in a densely populated city with several old and weak structures such as Delhi can be devastating and highlights the hazard potential due to local earthquakes here. The envelopes of accelerograms have been generated at bed rock level from hypothetical moderate/strong earthquakes (M 5.5 - 6.0) in the National Capital Region to estimate the seismic hazard and risk from such events. The simulations have been done at number of points distributed on a grid. A semi- empirical technique has been used for this purpose. The peak ground acceleration values have been extracted from the simulated accelerograms and contoured to show the spatial distribution. The results of present analysis may be used for the preparation of scenario hazard maps of the region.

4 illus, 1 table, 19 ref

019066   Kundu A;Dutta D (NO, Centre for the Study of Regional Development, School of Social Science, New Delhi-110 067, Email: arnknd@live.in) : Monitoring desertification risk through climate change and human interference using Remote sensing and GIS techniques. Int J Geomatics Geosci 2011, 2(1), 21-33.

Threat of global climate change has radically increased the attention directed towards understanding the effect on environment and its natural and human induced changes. Climatic conditions along with certain human activities such as improper agricultural practices, violent use of fertilizers, overgrazing and other unsustainable practices have accelerated the conversion of fertile lands into arid lands and this eventually leads to land degradation and desertification. The term "desertification" indicates land degradation in arid, semi-arid and dry sub-humid areas resulting from climate variations and human activity. Stable degradation of vegetation cover is one of the basic characteristics of desertification process. Changes in vegetation cover of the Churu district of Western Rajasthan are very clearly detected from long term satellite data and it has been used for monitoring desertification process. In this paper, long term NOAA-AVHRR (1983-2003) data has been used to monitor desertification processes through NDVI time-trend. The study is based on the analysis of regional long term changes of vegetation conditions that indicates the ongoing desertification processes. Vegetation growth is entirely depended upon rainfall. Here, long term NDVI trend has been analysed corresponding with the long term annual rainfall (1983-2003). It identifies the areas affected by desertification process as a circumstance of climate change. The results confirmed that some parts of Churu district is under climatically induced desertification processes.

4 illus, 1 table, 32 ref

019065   Krishnakumar S;Menon N R (Processing Technology Dep, College of Fisheries, Panangad P.O., Kochi-682 506, Email: srikris_87@yahoo.co.in) : Image analysis in the morphometry of the Indian mackerel, Rastrelliger kanagurta (cuv.). J Mar Biol Ass India 2011, 53(1), 41-5.

Morphometrics are important in fish taxonomy and fishery biology studies. Nine standard morphomerric lengths, viz; total length, fork length, standard length, body depth, eye diameter, snout length, post orbital length, head length and caudal peduncle height of the Indian mackerel Rastrelliger kanagurla were measured by the conventional morphometric method and also using an image analysis technique. Algorithm for the same is described. The image analysis showed good validation with corresponding conventional measurements. Nearly 50 percent of the measurements representing the nine morphometric lengths showed no difference and 31 to 34 per cent showed a difference of < 3 per cent. Another 11 to 19 per cent showed a difference <60> 5 per cent. The results proved that digital image processing and morphometric measurements using image analysis are dependable.

2 tables, 14 ref

019064   Krishnaiah C (NO, Central Water and Power Research Station, Khadakwasla, Pune-411 024, Email: krishnaiahc@yahoo.com ) : Importance of mapping of subsurface structures precisely in groundwater modeling. J Indian Geophys Union 2011, 15(3), 137-44.

Groundwater, an important source of water supply in many regions of India, has been incessantly contaminated from various man made and natural pollution sources. Thus, concern over the potential for migration of wastes in the subsurface has generated a great deal of interest in the study of mechanisms responsible for contaminant transport through groundwater. Numerical models have frequently been proved to be inadequate in spite of considerable efforts made to represent the actual flow mechanism in the subsurface on which contaminant transport depends. However, when modifications representing the flow mechanisms related to some undetected heterogeneous subsurface features were made, improvements were obtained in the agreement between field and modeled flow results. This is because if the subsurface heterogeneities such as fractures, dykes, buried channels or lenses are not known precisely, there is a chance of missing the presence of higher or lower hydraulic conductivity zones, leading to erroneous predictions. In view of the above, finite element numerical modeling technique is used to study the effect of the presence of various subsurface structures, which control the flow mechanism and in turn alter the transport phenomenon. A base case of a homogeneous subsurface is considered and changes in the subsurface flow pattern aroused by heterogeneities were compared and examined. The study indicated that the spread of pollution depends on hydrogeology at the source. It is noticed that the existence of dykes, fractures and buried channels and their orientation modeled in the area greatly influenced the spread of pollution. The spread of contamination also depends on presence of lenses like clay or sand. From these results it can be concluded that if the subsurface is not precisely mapped, the groundwater models may be proved inadequate in the prognosis of contamination transport.

3 illus, 2 tables, 10 ref

019063   Kouassi A M;Koffi Y B;Kouame K F;Lasm T;Biemi J (Earth Sciences and Mineral Resouraces Dep, Institut National Polytechnique Felix Houphouet-Boigny, PoBox 1093, Yamoussoukro, Email: michel.a_kouassi@yahoo.fr) : Modeling of annual flows using a conceptual model and an artificial neural network model in the N'zi-Bandama watershed (Cote d'Ivoire). Int J envir Sci 2012, 2(4), 2063-75.

Study presents a comparison between two models of the rainfall-runoff transformation on an annual basis: a conceptual model and an artificial neural network (ANN). Both models are applied to three watersheds of the N'zi River (Bandama) in C“te d'Ivoire. The comparative analysis is based on the performances of simulation in terms of Nash-Sutcliffe criterion. The models have been tested on two periods, a dry (1973-1997) and a wet one (1961-1972). The input data of the two models are the rain and the potential evapotranspiration to annual time step. The main results of this work show that the performances of both models (conceptual and neuronal) remain satisfactory in general with Nash-Sutcliffe criterion higher than 60%. These models appeared also robust and suitable for the simulation of the annual flows of rivers. The comparison of the two models has showed that the neural network performed significantly better than the conceptual model.

4 illus, 1 table, 31 ref

019062   Joshi P C (NO, Maulana Azad National Institute of Technology, Bhopal, Madhya Pradesh, Email: skkatiyar7@rediffmail.com) : Performance evaluation of vegetation indices using remotely sensed data. Int J Geomatics Geosci 2011, 2(1), 231-40.

Vegetation is one of the most important components of the ecosystems. Knowledge about variations in vegetation species and community distribution patterns, alternations in vegetation phonological (growth) cycles, and modifications in plant physiology and morphology provide a valuable insight in to the climate, geologic and physiographic, characteristics of an area, so mapping vegetation cover is important to understand various ecological processes occurring in nature, their relationship and the various geomorphological changes occurring over the period of time. Remote sensing is the advanced tool for surveying. It provides the synoptic view of the area. Remote sensing satellites provide data with different spatial, spectral, radiometric and temporal resolutions. Based on requirement and level of study the different data products can be used for mapping. Mapping vegetation through remotely sensed images involves various considerations, processes and techniques. Increasing availability of remotely sensed images due to the rapid advancement of remote sensing technology expands the horizon of our choices for imagery sources. Various sources of imagery are known for their differences in spectral, spatial, radiometric and temporal characteristics and thus are suitable for different purposes of vegetation mapping. Various techniques have been developed to map the vegetation with varying accuracies and cost. The simplest one is to use vegetation indices, they are easy to understand and calculate. Various vegetation indices have been designed and have their specific utility for vegetation mapping. Some vegetation indices not only help to identify vegetation but also help to identify and map other land cover classes. The study will throw light on various vegetation indices developed, their applications and provide a detailed comparison study for their mapping efficiency based on spatial resolution of data used. This study reveals that NDVI gives the better result in terms of overall accuracy to assess the vegetation.

6 illus, 2 tables, 7 ref

019061   Ibitola M P;Ebinola O A;Akinnigbagbe A E (NO, Nigerian Institute of Oceanography and Marine Research, 3, Wilmot Point Road, Victoria Island, P.M.B. 12729, Lagos, Nigeria, Email: mayoribi@yahoo.co.uk) : Electrical resistivity method in delineating Vadose and Saturated Zone in some selected dumpsites in Ibadan part of South-Western Nigeria. Int J Geomatics Geosci 2011, 2(1), 164-78.

Impact of solid waste disposal on the groundwater within the vadose and saturated zone of two dumpsites namely Aba-Eku and Ajakannga in Ibadan Metropolis was investigated using Vertical Electrical Sounding (VES) to determine the depth and thickness of subsurface layers. Aba-Eku Landfill site is located at the extreme south-western area of Ibadan, along Ijebu road covering an area of approximately 3.5 acres, while that of Ajakannga landfill site is located at the south-eastern area of Ibadan, along Old Ijebu, covering an area of 3 acres, The areas under investigation, Ajakannga and Aba-Eku landfill sites are located within the Oluyole Local Government Area and Ona Ara Local Government in Ibadan, Oyo State respectively. Ajakannga is located between latitude 3° 50 187 and 3° 50 696 and longitude 7° 18 021 and 07° 18 997, Aba-Eku in Ona Ara Local Government is at latitude 3° 59 009 and 3° 59 973, longitude 7° 19 270 and 7° 19 843. Both qualitative and quantitative interpretations of the field data were carried out from Vertical Electrical Sounding (VES). The qualitative interpretation reveals points of anomalous resistivity along the traverses of 10m station separation. Partial curve matching and computer assisted iteration techniques were used for the interpretation of the VES data. The approximated topography of the dumpsite was plotted using GPS readings. The pictorial pattern produced gives an elevation model of the two dumpsites. An integrated analysis of qualitative and quantitative interpretations reveals the lithologies of the subsurface for VES with topsoil (0.5m-1.0m) with resistivity ranges from (9.2-68.3)Ohm-m, clayey soil (2.0-11.3m) with resistivity ranges from (2.2-12.30)Ohm-m, overlying the fresh basement of unknown thickness of the respective dumpsites. The result from the VES data gives a qualitative lithology of topsoil and clayey soil (aquitard) which has a low resistivity zone <60>100 Ohm-m, underlain by higher resistive basement. The combination of both interpretations obtained from geophysical survey and the digital elevation map was used for the establishment of the environmental and health hazards associated with groundwater movement within the subsurface (vadose and saturated zones) along the two dumpsites.

3 illus, 2 tables, 31 ref

019060   Hutti B;Nijagunappa R (Environmental Science Dep, Gulbarga University, Gulbarga-585 106, Email: urbasu@gmail.com) : Identification of groundwater potential zone using geoinformatics in Ghataprabha basin, North Karnataka, India. Int J Geomatics Geosci 2011, 2(1), 91-109.

Systematic planning of groundwater exploitation using modern techniques is essential for proper utilization and management of this precious but shrinking natural resource. With the advent of powerful and high-speed personal computers, efficient techniques for water management have evolved, of which Geoinformatics technology includes RS (Remote Sensing), GIS (Geographic Information System) and GPS (Global Positioning System) are of great significance. In the present study, an attempt has been made to delineate possible groundwater potential zones in the Ghataprabha sub basin of Krishna river, Karnataka using Geoinformatics technology. The thematic layers considered in this study are lithology, landform, drainage density, recharge, soil, land slope and surface water body, which were prepared using the Google Earth imagery and conventional data. All these themes and their individual features were then assigned weights according to their relative importance in groundwater occurrence and the corresponding normalized weights were obtained based on the Saaty's analytical hierarchy process. The thematic layers were finally integrated using AutoDeskMAP and MapInfo GIS software to yield a groundwater potential zone map of the study area. Thus, three different groundwater potential zones were identified, namely `good', `moderate' and `poor'. Moreover, the average annually exploitable groundwater reserve in the good zone was estimated to be 915 million cubic meter (MCM), whereas it is 381.25 915 MCM for the moderate zone and 228.75 MCM for the poor zone. Finally, it is concluded that the Geoinformatics technology are very efficient and useful for the identification of groundwater potential zones.

9 illus, 6 tables, 34 ref

019059   Gupta R K (Geography Dep, Delhi School of Economics, University of Delhi, Delhi-110 007, Email: gisrs@oneindia.com) : Multi-temporal and multi-resolution satellite data for urban land use study through change detection techniques. Int J Geomatics Geosci 2011, 2(1), 196-218.

Study was focused on the monitoring of land use land cover over 34 years. The study has based on secondary and satellite data along with statistical techniques as well as limited field verification. Jaipur City is situated in the North West zone of India. Its population has grown from 0.3 million in 1951 to 2.3 million in 2001 and 2.9 million in 2009. The annual average growth rate from 1971 to 2001 has been in the range of 4.1 to 4.7. The growth rate was the highest in the year 1981 but declined sharply by 0.6 per cent in 1991 and in grew again by 0.2 per cent in 2001. The impact of such growth is seen in the change in land use and led to the congestion of walled city. The population growth has major driving forces of land use change. The crop land has shrinked to 1.60 sq km/year, fallow land 2.94 sq km/ year, wasteland 0.59 sq km/year during 1975-2009, whereas the built-up land has increased in the rate of 4.46 sq.km/ year or 1.02 per cent/year. Based on the use of multi resolution and multi temporal satellite data of 1975 to 2009, the spatial and temporal changes in the various types of land uses of city are detected and discusses.

12 illus, 2 tables, 14 ref

019058   Gopalan C V (Marine and Coastal Sueveys Div, Geological Survey of India, Mangaladevi Road, Pandeshwar, Mangalore-575 001, Email: gopalancv@yahoo.com) : Comparative study of the groundwater potential in hard rock areas of Rajapuram and Balal, Kasaragod, Kerala. J Indian Geophys Union 2011, 15(3), 179-85.

Groundwater exploration in hard rock terrain due to the restricted movement/occurrence of water, remains a challenging task. Resistivity of rock formation gives an indication of groundwater occurrence with an established inverse relationship. Resistivity surveys carried out in Rajapuram and Balal areas of Kasaragod district show contrasting results whereas the former is totally devoid of groundwater reserves while the latter has good potential. In Rajapuram, where the surface is covered with thick laterite, the resistivity values vary from 1795 ohm-m to 621 ohm-m from surface to depth of 100 m. The interpretation of resistivity data using inverse slope method shows that there are three layers/formations below the surface. They are (1) Laterite cover at the top with a resistivity of 1000 ohm-m (0-30m) followed by (2) Less fractured rock with a resistivity of 400 ohm-m (30-60m) and (3) Massive rock with resistivity of 746 ohm-m (60-80m). Here, all the formations are dry and this site cannot be reccommended for bore well. In Balal area, where surface is covered with soil, the resistivity value ranges between 133 ohm-m to 253 ohm-m. The results of resistivity data shows three layers/formations. They are : (1) soil cover with resistivity of 118 ohm-m (0-15m) at top followed by (2) Less fractured rock with resistivity of 400 ohm-m (15-35m) and (3) Highly fractured rock with resistivity of 143 ohm-m which contains water at a depth of 35m to 50m. The site is reccommended for bore well with total depth of 50m and casing of 15m.Exploratory drilling confirms a discharge of 3 litres per second.

3 illus, 4 tables, 16 ref

019057   Ghosh S (Post Graduate Geography Dep, The University of Burdwan, Burdwan, West Bengal, Email: sandipanghosh19@gmail.com) : Quantitative and spatial analysis of fluvial erosion in relation to morphometric attributes of Sarujharna Basin, East Singhbhum, Jharkhand. Int J Geomatics Geosci 2011, 2(1), 71-90.

Being the south-eastern part of famous Chotanagpur Plateau of India, the Sarujharna Basin is deemed to be considered as a small museum of Indian geology and geomorphology. On the tectonically stable and frequently modified Dhanjori Highlands (south-west of Singhbhum Shear Zone, copper belt) rivers like Sankh, Netra, Sarujharna, Jou, Gara etc. crave out several geomorphic architects (youth-old phase) which signify the variable intensity of fluvial erosion. Having different magnitude of rock r‚sistance and spatial variability of forest cover, the monsoonal wet-dry type of climate plays a crucial role in hillslope erosion and channel erosion. Emphasizes on the spatial distribution and quantification of fluvial erosion taking drainage basins and slope facets as an ideal geomorphic unit. Side by side, to realize the pattern of erosion we have focused on surface runoff, length of overland flow, constant of channel maintenance, hillslope erosion model, length and number of 1st order stream which are the indirect morphometric measurements of normal erosion. Along with it Geographical Information System (GIS) is used to depict the physical appearance of erosion in thematic maps.

11 illus, 3 tables, 30 ref

019056   Gawali P B;Waghmere S Y;Carlo L;Patil A G (NO, Indian Institute of Geomagnetism, New Panvel (W), Navi Mumbai-410 218, Email: pravin@iigs.iigm.res.in) : Geomagnetic secular variation anomalies investigated through tectonomagnetic monitoring in the seismoactive zone of the narmada-son lineament, Central India. J Indian Geophys Union 2011, 15(2), 61-74.

Data from repeated geomagnetic observations at seventy stations on the five profiles have revealed secular variation anomalies of the total geomagnetic field in the seismically active area of Jabalpur and adjoining regions, in the Narmada-Son Lineament (NSL), Central India. For this tectonomagnetic monitoring, a reference base station was established within study area at seismic observatory Jabalpur. Using proton precession magnetometers with sensitivity 0.1 nT, simultaneous measurements of the total geomagnetic field were made annually at the base station and all field stations. Seven cycles of repeated observations have been performed between 2003 and 2009. For data analysis, a difference method has been applied and the residuals calculated as secular variations of the total geomagnetic field with values ranging from ±0.1 nT/yr to ±9.5 nT/yr over different stations. The anomalies in secular variation of the total geomagnetic field may be related to anomalous accumulation of tectonic stresses and tensions on the deep fault zones and crustal blocks of the NSL as a piezomagnetic effect. However, the geomagnetic depth sounding data have revealed high electrical conductivity anomaly due to saline fluids in the deep crust of Jabalpur area. The fluids related to electrokinetic effect can not be ruled out for causing the anomalies in the secular variation of total geomagnetic field. Thus, tectonomagnetic phenomenon such as piezomagnetic and/or electrokinetic effect or, both these mechanisms may have caused the secular variation anomalies in the seismoactive zone of NSL.

7 illus, 60 ref

019055   Ganapathy G P (Center for Disaster Mitigaton and Management, VIT University, Vellore-632 014, Email: seismogans@yahoo.com) : Use of DesInventar database for preparation of disaster management plan for Vellore district, Tamil Nadu State, India. Int J Geomatics Geosci 2011, 2(1), 282-8.

Natural disasters itself are inevitable and have a drastic effect on our lives and have proven to be detrimental to our economy as well. The risk of human life due to natural disasters can be avoided by looking back into our past. The method of assessing the impact of past occurrences of hazards will provide us with enough information to react effectively and be prepared for all eventualities. The past experience has shown that the occurrence of small and medium scale disasters can be a precursor to big disasters, and the cumulative impact of small and medium disasters may equal or even exceed that of big disasters. The study based on DesInventar Methodology, which analyse the small and medium level disasters and their impact on human lives and Infrastructures were studied for the duration of 30years from 1976 to 2006 for the Vellore District in the State of Tamil Nadu. The data on past disaster events were collected from authenticated sources through data cards and entered in the DesInventar database for analysis. About 12 major disaster events were considered for the present study, which have high frequency of recurrence in the Vellore District. The output spatial maps clearly indicate the multi disaster affected taluks of Vellore district. These maps will be useful to the stakeholders and Government officials to assess the damage for a forthcoming disaster event and have a clear disaster management plan for the district.

5 illus, 1 table, 6 ref

019054   Ganapathi Subramanian R;Subramanian V;Sukumar S (Geology Dep, National College, Trichy, Tamil Nadu) : Pre- and post-monsoon variation in physico-chemical characteristics in groundwater quality of parts of Tirunelveli district, Tamil Nadu, India. Int J Geomatics Geosci 2011, 2(1), 300-10.

Total of 43 groundwater samples for three representative seasons were collected from parts of Tirunelveli district of Tamilnadu, India to decipher hydrogeochemistry and groundwater quality for determining its suitability for drinking and agricultural proposes. The water is neutral to alkaline in nature with pH ranging from 7.1 to 8.6 with an average of 7.8 pre monsoon and 7.7 post monsoon. The abundance of major ions in the groundwater was in the order of Na Ca <62> Mg <62>Na+K<62>Cl <62> SO4<62> TDS<62> TH. As per the classification of water for irrigation purpose, water is fit for domestic and agricultural purposes with minor exceptions irrespective of seasons.

9 illus, 3 tables, 10 ref

019053   Forkuo E K;Nketia A K (Geomatic Engineering Dep, Kwame Nkrumah University of Science and Technology, Private Mail Bag, Kumasi, Ghana, Email: eforkuo.soe@knust.edu.gh) : Digital soil mapping in GIS environment for crop-land suitability analysis. Int J Geomatics Geosci 2011, 2(1), 133-46.

Geo-computational technologies have emerged as useful tools in diverse range of application traditionally catered for by soil surveys. These are used to record, store, manipulate and retrieve data from many soil observations including their location and elevation on the ground. The purpose of this study is to produce a digital soil map and to develop an interactive geodatabase with crop-land suitability analysis on the growth and production requirement of oil palm, cassava, and citrus in the study area. Also, to develop a choropleth map that is able to provide a visual view of all potential areas within the district study area where the selected crops can be grown. A geodatabase for crop land suitability analysis (Crop Mapper) was developed with the combination of ESRI ArcGIS and Microsoft SQL Server. The attribute data of the soils are effective depth, texture, drainage, pH, course fragments, slope, base saturation and climatic conditions such as rainfall, temperature and length of dry season. These attributes which were linked with spatial data to develop the soil geodatabase model, were considered as important criteria to determine the crop land suitability. The developed Crop Mapper has the ability to upload a soil map of the study area, perform spatial queries by attribute or using a query builder, and perfumes suitability analysis on three different soil series for three selected crops. Also, it is user friendly, fast and gives more accurate results.

7 illus, 1 table, 29 ref

019052   Elakkiya P (Geology Dep, University of Madras, Chennai, Tamil Nadu, Email: elakkiya20787@gmail.com) : Environmental and ecological parameters of recent Ostracods in Cauvery river estuary, Poombuhar, Tamil Nadu, India. Int J envir Sci 2012, 2(4), 2104-9.

Study deals with the study of some recent benthic ostracoda in the sediments collected from the Cauvery river estuary of Poombuhar. The sediment samples have been collected from 9 stations from the Cauvery river estuary of the study area. In the present study, 17 ostracod species belongs to 12 genera, 10 families, 3 super families and 2 sub orders. Spatial distribution of ostracoda of the study area reveals that the higher population is found only in the samples collected from the mouth of the estuary. Of the 17 ostracoda identified, the six species cytherelloidea leroyi, Paijenborchella sp, stigmatocythere indica, Keijella reticulata, Loxoconcha sp., and Phlyctenophora orientalis are considered to be wide spread and abundantly occurring species in the present study. Higher diversity and population of ostracod species are noticed in stations 8 and 9 because of their favourable niche. The substrate of present study area is seen to consist of silty-clay sand and clay sand. The most accommodative substrate for higher population is clay sand.

4 illus, 8 ref

019051   Ehsan G (Geography Dep, Payame Noor University, P.O. Box 19395-3697) : Investigation of water supply systems in semi-arid regions of Iran: a case study of western part of Tehran Province. Int J envir Sci 2012, 2(3), 1435-48.

Drought problem has been resulted social and economical effects in several arid and semi-arid regions of Iran. Especially, on environmental and agricultural aspects. Tehran Province involves three river basins and seven regions according to the classification of water management study units employed in the Master plan. In this regard, long-term records (27 years) of precipitation and runoff that concern to more than four hydro - meteorological stations, which located in different sites have been analyzed. Water production in the study area despite that Tehran's water supply is currently groundwater (40%) and surface water (60%) conveyed from Karaj, Latian and Lar dams. The area recently experienced its worst water crisis due to excessive water consumption by Tehranis and that will be further aggravated not only by the impacts of uncontrolled immigration to the capital city of Tehran along with rapid population growth but also by uncontrolled pumping up of groundwater. Appropriate measure are thus required to exploit new surface water resources, as well as the effective use of available water recourses including a legal framework and institutional strengthening to limiting ground water use.

7 tables, 8 ref

019050   Dushiyanthan C;Raja Kumar T;Karthikeyan K; Thiruneelakandan B;Davidraju D;Manoharan K (Earth Sciences Dep, Annamalai Univ, Annamalai Nagar-608 002, Email: hydrodushi@gmail.com) : Delineation of shallow aquifer zones using electrical resistivity and bore hole litholog details in the northwestern part of Bhuvanagiri, Chidambaram taluk, Cuddalore district, Tamil nadu. J Indian Geophys Union 2011, 15(3), 171-7.

Five Vertical Electrical Soundings were carried out in the northwestern part of Bhuvanagiri, Chidambaram Taluk, Cuddalore District, Tamilnadu to identify the shallow fresh water zones and understand the sub-surface lithological sequence. The maximum electrode separation used is 100m by Schlumberger configuration. Geologically, sedimentary rocks of cretaceous and Mio-Pliocene with alluvium are present. The resistivity data was interpreted by using IPI2WIN software. The maximum error percentage observed was 4.3. The interpreted result shows four layer strata. The resistivity and layer thickness of the first layer are 2.82 ohm m to 10.9 ohm m and 0.9m to 4.77m respectively. The resistivity and layer thickness of the second layer varies from 1.66 ohm m to 17.7 ohm m and 3.61m to 12.0m respectively. The VES number 1 and 4 results indicate the shallow aquifer zones. The interpreted results have been compared with the subsurface strata to validate the results.

8 illus, 1 table, 7 ref

019049   Dey S;Debbarma C;Sarkar P;Paul S (Geography and Disaster Management Dep, Tripura Univ, Suryamaninagar-799 130, Email: sudip_geo@rediffmail.com) : Influence of vegetation cover on short distance variations of soil resistivity: an experiment on greyscale (digital) imaging and indexing. J Indian Geophys Union 2011, 15(1), 25-34.

This paper attempts to assess the influence of vegetation cover upon physical character of soil within short distance. For that purpose a very small slope of 6m was selected which is covered by various types of natural vegetations like Cynodon dactylon, Lantana camara, Calamus tennis, and Acacia Arabia and Dracaena spicata. Soil resistivity metre was used for measuring the electrical conductivity of soil in this area. In the field 4 pin method was used and resistivity character of soil was calculated by p = 27πaR. A greyscale index of the soil resistivity was prepared within black to white range. Micrographic study of the soil particles were also done to understand the physical characters of the collected soil samples collected from survey points. Through the study it has been observed that though the area is very small, change of slope angle influenced upon the pattern and distribution of vegetation cover. This study also opens the fact that even within a small area though the general compositions of the soil are similar, resistivity character is influenced by the variation of vegetation cover.

5 illus, 29 ref

019048   Chopra N (Geology Dep, National Defence Academy, Khadakwasla, Pune-411 023, Email: narayan_chopra@yahoo.com) : Land use/land cover information at various levels from different scales of remote sensing data of southern part of Sonbhadra district, Uttar Pradesh. Int J Geomatics Geosci 2011, 2(1), 336-48.

Study, through visual interpretation, aims to obtain the information at various levels on the Land use/Land Cover pattern in the region south of the River Son, Sonbhadra Distict, U.P. Remote Sensing data of different scales, viz., 1RS-1A (LISS-I) standard False Colour Composites (FCCs) on 1:1m, 1:500,000 and 1:250,000 scales for the period of Feb. 1991 & also FCC data on 1:50,000 of 1RS-1A (LISS-II) of the same time period for the entire study area (consisting of 14 scenes) have been used in the study. Moreover, geocoded multi-temporal FCC's of four different time periods for a part of the study area (63 P/7) has been used for standardisation. Finally a list of Land Use/ Land Cover Categories present have been compiled highlighting the problems in identifying and delineating the same. The result shows progressive increase in the Land Use/ Land Cover Categories with increasing scale and have revealed area variations of different Land Use/ Land Cover units.

5 illus, 1 table, 22 ref

019047   Chitra C;Alaguraja P;Ganeshkumari K;Yuvaraj D;Manivel M (Geology Dep, Bharathidasan University, Tiruchirappalli-620 024, Email: chithrachinnain@gmail.com) : Watershed characteristics of Kundah sub basin using remote sensing and GIS techniques. Int J Geomatics Geosci 2011, 2(1), 311-35.

Study area Kundha watershed, the area chosen for the present study lies in the Nilgiri hills which covers a portion of the Nilgiri district of Tamil Nadu state. It lies in the South Western end of Bhavani basin. It is located bound by Geo Coordinate between 76° 35' and to 76° 45' N and 11° 15' to 20° E and parts of udagamandalam. It covered by 1:50,000 scale Survey of India toposheet Nos. 58A/11, 12. It falls a part of Palaghat District of Kerala and the Nilgiris and Coimbatore Districts of Tamil Nadu State in Western Ghats The covering an total area of Kundah watershed is 266. Sq.km. the Peninsular granite- gneiss, Archeans, Charnokites Dharwar gneiss and schist comprise the major lithological units. The watershed forms part of Nilgiri plateau and consist of poly-convex residual hill/ridges separated by flat valley flood, denudational hills and remnants of lder plantion surfaces, which are dissected. The highest point (2637m above M.S.L) lies at a place within Dodda Betta estate. The river kundah and its tributaries drain the watershed. The climate of the area is sub-humid and sub - tropical with a mean anuual rainfall 1250mm to 1500mm at kundah watershed. The mean annual temperature 14.5° C and 28.6C respectively. Natural vegetation comprises of evergreen and semi-evergreen types. Among plantations tea and wattle plantations are very common.

5 illus, 6 tables, 20 ref

019046   Chandra H;Rastogi R G (NO, Physical Research Laboratory, Ahmedabad-380 009, Email: hchandra@prl.res.in) : Space weather event of 25 september 1998: ionospheric response. J Indian Geophys Union 2011, 15(1), 45-59.

Ground geomagnetic data at a chain of stations in India, interplanetary magnetic field, solar wind parameters and the ionospheric data at Thumba are examined to study the great geomagnetic storm of 25 September 1998. The geomagnetic storm is unique because of the strong counter electrojet in the morning, strong electrojet around noon and then counter electrojet in the afternoon hours caused by the enhanced solar wind density and velocity in association with the changes in IMF Bz. Disappearance of Esq in the morning hours, absence of ionization anomaly in the pre-noon hours, strong ionization anomaly near noon and later the absence of the post-sunset height rise and equatorial spread-F on 25 September 1998 are observed as a consequence of the imposition of electric fields associated with the space weather event.

12 illus, 40 ref

019045   Chandel V B S;Brar K K;Chauhan Y (Centre of Advanced Study in Geography, Geography Dep, Punjab University, Chandigarh) : RS & GIS based landslide hazard zonation of mountainous terrains : a study from middle Himalayan Kullu district, Himachal Pradesh, India. Int J Geomatics Geosci 2011, 2(1), 121-32.

Landslides are short lived and suddenly occurring natural phenomena; it is just a hazard when it occurs in an uninhabited place, however it turns into a disaster causing extraordinary landscape changes and destruction of life and property when it occurs in the vicinity of human habitation. Landslides are particularly common and cause massive damage in tectonically active Himalayas. This work conducts a landslide hazard zonation in western Himalayan district of Kullu in Himachal Pradesh using remote sensing and GIS. The western Himalayan district of Kullu with a location on the southern side of Pirpanjal mountain range, an established history and inherent susceptibility to massive landslides has been chosen for landslide hazard zonation. The satellite imageries of LANDSAT ETM+, IRS P6, ASTER along with Survey of India (SOI) topographical sheets formed the basis for deriving baseline information on various parameters like slope, aspect, relative relief, drainage density, geology/lithology and land use/land cover. The weighted parametric approach was applied to determine degree of susceptibility to landslides. The landslide probability values thus obtained were classified into no risk, very low to moderate, high, and very high to severe landslide hazard risk zones. The results show that over 80 per cent area is liable to high-severe landslide risk and within this about 32 per cent has very high to severe risk.

3 illus, 3 tables, 35 ref

019044   Bhattji N S;Ray Chudhury N;Shah D G;Desai N D (Coastal Zone Studies Project, Faculty of Science, The Maharaja Sayajirao Baroda Univ, Vadodara, Email: nayruti@gmail.com) : Sedimentation pattern in pirotan reef, gulf of Kachchh, India. J Mar Biol Ass India 2011, 53(1), 1-7.

Reef building corals flourish in tropical and subtropical clear waters within a narrow range of bio-physical environmental parameters. Among the parameters, sedimentation affects corals through tissue damage. Multi-temporal, high spatial resolution, multi-spectral satellite images can be integrated on a CIS platform to identify the micro reef-zones vulnerable to future sedimentation. This study attempts to identify micro-level regions of Pirotan reef, part of Jamnagar Marine National Park, Gujarat, India. RESOURCESAT (IRS P6) LISS IV MX images were used to study the reef-scale sedimentation pattern for a period of four years (2004-2007). Digitally classified images were used as base reference to create vector inputs for identifying the micro-level, reef-scale changes in sedimentation pattern. Close observations on the sedimentation pattern in Pirotan reveal an ongoing process of sand filling in the central tidal pool, extension of a juvenile beach within the core region of the reef, a NE-SW trendline demarcating a clear distinction between the relatively sediment-free seaward face of the reef and the contrasting eastern and south-eastern areas showing high sediment loading.

5 illus, 1 table, 11 ref

019043   Banukumar K;Pannerselvam A;Aruchamy S;Ganesh A (Geography Dep, Periyar E.V.R. College, Tiruchirappalli, Tamil Nadu, Email: kbanukumar@gmail.com) : Surface water mapping for watershed management using geospatial technique. Int J Geomatics Geosci 2011, 2(1), 289-99.

Effective data regarding surface water availability for watershed management demands application of geospatial techniques such as remote sensing, image processing techniques and GIS. The study is attempted to investigate the feasibility of surface water mapping from moderate resolution image with the aid of image processing techniques for the Ambuliyar sub watershed covering largely the semi arid tract of Pudukkottai district. The results of the study shows that the application of Tasseled Cap Transformation is useful for reducing image dimension and the Crisp filter algorithm has been used for sharpening the image for enhancing edges. Further, the supervised classification technique with maximum likely hood classifier has been used to separate the tanks and non-tanks pixels. The comparative overlay assessment of tanks extracted from the Survey of India Toposheet in the scale of 1: 50,000 with shows considerable overlap with several isolated pixels similar to the tanks owing to the saturated soil at the time of image acquisition and illumination characteristics of the soil and depth perception of the tanks. Watershed management, Surface water configuration, Geospatial Techniques, Landsat ETM, Tasseled Cap transformation, Crisp filter, Maximum likely hood classifier Effective data regarding surface water availability for watershed management demands application of geospatial techniques such as remote sensing, image processing techniques and GIS. The present study is attempted to investigate the feasibility of surface water mapping from moderate resolution image with the aid of image processing techniques for the Ambuliyar sub watershed covering largely the semi arid tract of Pudukkottai district. The results of the study shows that the application of Tasseled Cap Transformation is useful for reducing image dimension and the Crisp filter algorithm has been used for sharpening the image for enhancing edges. Further, the supervised classification technique with maximum likely hood classifier has been used to separate the tanks and non-tanks pixels. The comparative overlay assessment of tanks extracted from the Survey of India Toposheet in the scale of 1: 50,000 with shows considerable overlap with several isolated pixels similar to the tanks owing to the saturated soil at the time of image acquisition and illumination characteristics of the soil and depth perception of the tanks.

7 illus, 5 tables, 23 ref

019042   Anila Kumary K S;Rajimole K R (School of Applied Life Sciences, Mahatma Gandhi Regional Centre Univ, Pathanamthitta-689 645, Email: ksanilakumary@yahoo.co.in) : Intertidal sedimentology along ambalappuzha coast, Kerala. J Mar Biol Ass India 2011, 53(1), 116-20.

Ambalappuzha coast in central Kerala is well known for persistent occurrence of mud bank at Purakkad. The results of the investigation carried out during July - December 2000 on sediment characteristics of Purakkad mud bank shelf, surrounding shelf of Ambalappuzha outside the mud bank and the shelf of the backwater outlet at Thottappally are reported. Considerable variations in sediment composition in relation to the environmental conditions were observed. Fine-grained particles in the mud bank shelf were the maximum during the active phase of mud bank. The mud bank shelf sediment was quite distinctive from the intertidal sediments outside the mud bank area, in having much higher values of organic matter, pH, chloride, sulphate and alkalinity, but with low phosphate content.

10 illus, 1 table, 11 ref

019041   Anil N C;JairSankar G;Rao M J;Prasad I V R K V;Sailaja U (Geo-Engineering Dep, Andhra Univ, Visakhapatnam-530 003) : Land use/land cover and change detection from parts of South West Godavari district, A.P- using remote sensing and GIS techniques. J Indian Geophys Union 2011, 15(4), 187-94.

Land use/land cover is an important component in understanding the interactions of the human activities with the environment and thus it is necessary to monitor and detect the changes to maintain a sustainable environment. In this paper an attempt has been made to study the changes in land use and land cover of southern part of West Godavari district. The study was carried out through Remote Sensing and GIS approach using SOI toposheets, Landsat imagery of 2000 and IRS-1D-LISS-III 2010. The land use/land cover classification was performed based on the Survey of India toposheets and Satellite imageries. GIS software is used to prepare the thematic maps and ground truth observations were also performed to check the accuracy of the classification. The present study has brought out that the aquaculture tanks have been decreased from 33.02% to 25.66% during 2000-2010 with a net decrease of 7.34%. Agriculture was also decreased from 43.32% to 37.75% with a net decrease of 5.56% during 2000-2010. The reasons for this decrease have been discussed. However, some plantations mixed with crops, fallow lands and settlements have shown considerable increase. The areas under natural streams/rivulets, mangroves etc have shown no significant change and can be considered as a positive sign for sustainable development. Though there are some changes detected in landuse/land cover analysis of the period 2000-2010, it does not indicate any significant environmental impact on the study area. However, it is necessary to closely monitor the landuse/land cover changes for maintaining a sustainable environment.

6 illus, 2 tables, 8 ref

016870   Tyagi A;Singh U P;Mohapatra M (NO, India Meterological Dep, New Delhi-110 003, Email: ajit.tyagi@gmail.com) : Weather & Weather systems at Schirmacher oasis (Maitri) during recent two decades. Mausam 2011, 62(4), 513-34.

Indian Antarctic station Maitri experiences varying external influences from interior of east Antarctica as well as moving depressions and cyclones along the coast. The relative position of circumpolar trough and strengthening of high pressure centre near pole influences variation of atmospheric pressure at Maitri. The diurnal, daily and seasonal variation of temperature mainly depend upon moving pressure systems, katabatic winds, change of solar insulation with change of seasons, reflectivity from clouds and snow surface. The katabatic winds prevail over Maitri which is highly directional from South- East sector due to increase of slope towards south. The blizzards are main weather at Maitri, fog and white out are occasional phenomena. The precipitation is mostly in form of snowfall but rain is very rare at Maitri. Heavy or moderate snowfall indicative of active front leading edge of warm air masses being transported southwards. Strong temperature variant near Schirmacher oasis give precipitation in form of snow. Fog occurred due to slow movement of relatively warm air from lower latitude over the colder surface. Winter season witnessed more snowfall accumulation at Maitri than other season. During summer rise of temperature accompanied with absorption of latent heat by ice pellets in low level of atmosphere results precipitation in form of water droplets. Highest number of blizzards occurs during winter season whereas lowest number of blizzards occurs during summer season. Normally due to cyclonic activities, warm air masses transported towards the Schirmacher oasis which causes rise of temperature at Maitri. Longer duration of the blizzards over the station depends upon strength of slow moving blocking anticyclone situated east of Maitri at lower latitude. Tremendous fluctuation of atmospheric electric field observed before onset is a pre-indication of commencement of blizzards.

^iia16 illus, 1 table, 33 ref