000211   Tinti S;Armigliato R;Tonini R;Maramai A; Graziani L (Dipartmendo di Fisica, Univ di Bologna, Viale Carlo Berti Pichat, 8-40127 Bologna, Italy) : Assessing the hazard related to tsunamis of tectonic origin: a hybrid statistical-deterministic method applied to southern Italy coast. ISET J Earthquake Technol 2005, 42(4), 189-201.

Italy is one of the countries of the Mediterranean Sea most affected by tsunamis. Catalogues of Italian tsunamis show that Italian coasts were attacked by large tsunamis in the past that had catastrophic effects, causing thousands of victims and severe damage. Though the cases of tsunamis associated with volcanic activity and submarine slides cannot be neglected, most tsunamis were the results of coastal and submarine earthquakes. Therefore, assessing the occurrence probability of tsunamigenic earthquakes is an important contribution to the global evaluation of tsunami hazard. Improving a methodology used for a preliminary evaluation of tsunami hazard in Italy more than one decade ago, applies probabilistic seismic hazard techniques focussing on Calabria and Sicily, that are among the most active seismic and tsunamigenic regions in Italy. The estimated tsunami activity, expressed in terms of the number of expected events in a 10,000-year period with run-up heights exceeding a given threshold value, is compared with the information deducible from the most recent Italian tsunami catalogue.

8 illus, 1 table, 17 ref

000210   Tinti S;Armigliato A;Pagnoni G;Zaniboni F (Dipartimento di Fisica, Univ di Bologna, Viale Carlo Berti Pichat,8-40127 Bologna, Italy) : Scenarios of giant tsunamis of tectonic origin in the Mediterranean. ISET J Earthquake Technol 2005, 42(4), 171-88.

Scenarios represent a very useful technique for the definition and evaluation of tsunami hazard and risk for any given region, and a basic step in the frame of tsunami mitigation and preparedness and of sustainable coastal zone development. With the exception of very few countries, like Japan and the United States, emergency plans in the rest of the world have never taken serious care of tsunamis until the occurrence of the giant Indian Ocean tsunami on December 26, 2004. That event dramatically brought the problem of tsunami hazard and risk assessment to the general attention and showed the urgent need for implementation of tsunami early warning systems (TEWSs). The problem is particularly urgent for the Mediterranean countries that are known to have been attacked by numerous tsunamis in the past, several of which had catastrophic size and impact. An attempt to develop some simple scenarios of earthquake-generated tsunamis in the Mediterranean has been presented. Identifyed four different seismogenic areas in the western, central and eastern sectors of the basin. For each of them, taken into account a seismic fault capable of generating an earthquake with magnitude equal or larger than the highest magnitude registered in that region in historical times. Stimulated numerically the ensuing tsunamis, highlighting the basic features of the wave propagation and roughly identifying the coastal sectors that are expected to suffer the heaviest tsunami effects. One of the most important outcomes is that these scenario tsunamis attack the nearest coasts within at most 15 minutes, which poses serious constraints for designing appropriate TEWS for the Mediterranean.

11 illus, 4 tables, 55 ref

000209   Sugawara D;Minoura K;Imamura F;Takahashi T; Shuto N (Inst of Geol and Paleontology, Tohoku Univ, Aobayama, Sendai 980-8578, Japan) : A huge sand dome formed by the 1854 earthquake tsunmi in Suruga Bay, central Japan. ISET J Earthquake Technol 2005, 42(4), 147-58.

The 1854 Ansei-Tokai earthquake brought massive destruction to Suruga Bay, central Japan. The earthquake triggered a large-scale tsunami, which surged over the Pacific coast of Japan. Waves exceeding 13.2 m in height attacked Iruma, southeastern coast of Suruga Bay, and provoked peculiar types of tsunami sedimentation. On the coast of Iruma, a huge mound of shoreface sand, reaching more than 11.2 m above sea level, appeared after the tsunami run-up. Performed a historical and sedimentological survey to clarify the origin of the mound. Result of a field excavation and submarine investigation suggests that the sand came from the seafloor with a water depth of 20 to 30 m, and historical data illustrates a dramatic change of the landform by the tsunami run-up. Numerical examination of the tsunami implies that the coastal topography played an important role in excitation of the tsunami, and it induced the characteristic tsunami sedimentation.

8 illus, 22 ref

000208   Sisodia M S;Lashkari G;Bhandari N (NO, , , Email: msisodia@sancharnet.in) : Impact origin of the Ramgarh Structure, Rajasthan: some new evidence. J Geol Soc India 2006, 67(4), 423-31.

In the absence of definite evidence, no consensus exists regarding the origin of Ramgarh structure (N 25°20^': E 76°37^') located in the baran district of Rajasthan, India. A detailed survey of the structure was therefore undertaken during which it has been found impact spherules, diaplectic glasses and observed planar deformation features in quartz grains. These observations are indicative of impact since they require high pressure-temperature of 30-50 GPa, which is generally produced due to shock and not normally encountered in terrestrial processes such as volcanism and compression due to tectonic forces.

8 illus, 2 tables, 31 ref

000207   Sikka D R (NO, , 40, Mausam Vihar, Delhi-110 051, Email: drsikka@yahoo.com) : Major advances in understanding and prediction of tropical cyclones over north Indian Ocean. Mausam 2006, 57(1), 165-96.

Research on tropical cyclones in the north Indian Ocean has passed through different phases in the last 150 years and progress was made as the technology for more and better observations evolved. Till the middle of the 20th century, the only way of knowing about the formation and intensification of this disastrous phenomenon, while out at sea, was through rather sparse ship observations and hence the climatology of the cyclones, their surface structure, movement and the rules to avoid the damage to shipping at sea were emphasized in most of the research studies in India till 1960s. Introduction of new atmospheric technologies through weather radars, upper air soundings, weather satellites and computers have brought a phenomenal change in tropical cyclone research in different countries during 1950s to 1980s. The period also witnessed break-through in theoretical studies and the development of computer models to simulate the complete genesis cycle of tropical cyclones. Predicting the track of tropical cyclone also became an area of active research in this period and a variety of techniques were increasingly developed. During the last 10 years sophisticated high resolution models embedded within global circulation models have been developed in advanced countries and tested for predicting the development and movement of the system as an interactive process. In India, too such developments have been adopted.

2 illus, 7 tables, 284 ref

000206   Shivhare R P;Srinivas V S (NO, Directorate of Met Air HQ (VB), New Delhi, Email: rpshivhare@yahoo.com) : Tropical cyclonic storms - modeling studies in Indian Air Force. Mausam 2006, 57(1), 135-40.

Directorate of Meteorology is responsible for the provisioning of weather services for safe conduct of Indian Air Force (IAF) flying operations in the country. The Meteorological (Met) Section at IAF bases closely monitor a Tropical Cyclone formation, intensification and movement and issue storm warning to safeguard its valuable property that primarily includes Aircrafts. It also provides the weather services for all the helicopter/aircraft Rescue Operations that are taken up after the fury of the cyclone experienced at a place. Generation of real time forecast from model studies is in the Research Stage in IAF. A meso-scale model (MM5) studies of super cyclone of Orissa were carried out by IAF Met to generate forecast tracks of the Cyclone using Grell and Kain-Fritsch 2 (with shallow convention) cumulus parameterization scheme. The Grell scheme indicated the track slightly close to the actual track of the storm. The KF2 scheme led to the generation of the track that indicated the re-curvature of the system in to West Bengal and adjoining regions.

3 illus, 1 table, 3 ref

000205   Sarangi S;Gopalan K;Roy A B;Sreenivas B;Das Sharma S (NO, Natn Geophys Res Inst, Hyderabad - 500 007, Email: abroy_g@yahoo.com) : Pb-Pb age of carbonates of Jhamarkotra formation: constraints on the age of Aravalli supergroup, Rajasthan. J Geol Soc India 2006, 67(4), 442-6.

Lead Pb isochron age of carbonate rocks of the Jhamarkota Formation of the Aravalli Supergroup from the Udaipur sector in Rajasthan has been measured for the first time as 1921±67 Ma (2σ). Censiders lead this as a reset aged, as it is indistinguishable from the earlier reported Rb-Sr isochron age of 1900±80 Ma for the Darwal Granite formed synkinematically with the Aravalli deformation. the depositional age of the Jhamarkotra carbonates could be 200-300 Ma older as suggested by the positive δ¹³C anomalies noted in these carbonate rocks.

3 illus, 2 tables, 17 ref

000204   Saatcioglu M;Ghobarah A;Nistor I (Dep of Civ Engng, The Univ of Ottawa, Ottawa, Ontario, Canada) : Effects of the December 26, 2004 Sumatra earthquake and Tsunami of physical infrastructure. ISET J Earthquake Technol 2005, 42(4), 79-94.

Devastating earthquake and the resulting tsunami hit coastal areas of Indian Ocean on December 26, 2004. A team of Canadian engineers conducted a reconnaissance in Thailand and Indonesia. Their findings are presented paper in terms of performance of buildings, bridges, coastal structures and other physical infrastructure. It was observed that non-engineered reinforced concrete structures, low-rise timber frames and unreinforced masonry buildings suffered extensive damage due to hydrodynamic pressures generated by tsunami and impact forces induced by floating debris. Banda Aceh, Indonesia suffered extensive damage due to seismic excitations. A large number of non-engineered and engineered reinforced concrete frame buildings experienced partial or total collapse. A number of 3 to 5 story engineered reinforced concrete government buildings and shopping centers were damaged due to lack of proper seismic design practices. The engineering significance of disaster is presented with observations made during the reconnaissance visit.

33 illus, 5 ref

000203   Rambabu G (NO, INS Garuda Sth Nav Command, Kochi, Kerala, Email: gr_navy@yahoo.com) : QuikSCAT scatterometer wind data impact o tropical cyclone forecasts by mesoscale model. Mausam 2006, 57(1), 141-50.

Describes the positive impact of QuikSCAT Scatterometer data on tropical cyclone analyses and forecasts using a Mesoscale Model (MM5). QuikSCAT data is especially valuable because they are available in the data sparse genesis regions of tropical cyclones, and because they are available in cloudy and rainy conditions. The model used in the study, MM5 is known as fifth generation NCAR/Penn State Mesoscale model (MM5). In order to understand and investigate the impact of QuikSCAT Scatterometer wind data, simulation with and without assimilation of scatterometer data has been performed for a few tropical cyclone cases during the period 1999 to 2003. For a cyclonic situtaion, data of few ships of opportunity and of some coastal or island stations are only available. For the assimilation of observed data into MM5, a few passes of QuikSCAT at different times are available. These additional data strengthen the initial data for assimilation. The results showed that the initial field with the inclusion of scatterometer data was nearer to the actual situation. In the prediction experiment, it was also shown that the inclusion of satellite data improved the prediction up to 48 hrs.

9 illus, 1 table, 8 ref

000202   Rama Rao Y V;Hatwar H R;Agnihotri G (NO, India Meteorological Dep, New Delhi, Email: ramarao@imdmail.gov.in) : Tropical cyclones prediction by numerical models in India Meteorological Department. Mausam 2006, 57(1), 47-60.

Cyclone bogusing techniques followed in India Meteorological Department (IMD) has been discussed. Using the idealized vortex in the initial fields for Orissa super cyclone October 1999, the specialized cyclone model, Quasi-Lagrangian Model (QLM) 72 hours track forecast and also 36 hours forecast with IMD limited area model (LAM) were simulated. In this case, the QLM average track forecast errors based on 26-28 October initial conditions were 21 km for 24 hours, 91 km for 48 hours and 179 km for 72 hours. Also the QLM track forecast error statistics during the last 7 years 1998-2004 are discsussed. In addition, the impact of initial conditions on the LAM forecast was examined. It was observed that the mean (ensemble) forecast generated from different initial conditions was shown track error of 123 km in 24 hours at 81 kmin 36 hours forecast which is less than individual forecast. These experiments have established that the QLM model, with idealized vortex, provides track forecast within an accuracy level that was currently available from numerical models.

5 illus, 3 tables, 16 ref

000201   Ram Gopal (Geophysics Div, Geol Surv of India, Western Region, 15-16, Jhalana Doongri, Jaipur - 302 004) : Geoelectric exploration for concealed graphite zones within laterite capping in Karimukal area, Ernakulam district, Kerala. J Geol Soc India 2006, 67(4), 503-8.

The self-potential, resistivity and electromagnetic prospecting techniques used and the responses obtained over flaky graphite occurrences within laterite capping in Karimukal area, Ernakulam district, Keral has been discussed. The three main factors controlling these responses are the size and concentration of the conductive body, depth from surface and the country rock. Detailed self-potential (SP) surveys conducted in the area have delineated nine anomalous zones with peak negative values varying from -145 to -680 mV having width of 30 to 50 m and extending in strike length of 100 to 300 m. Graphite has been struck in five of these zones. Results of four more anomalies are yet to be tested. Resistivity and Horizontal loop electromagnetic (HLEM) surveys over SP anomaly zones have yielded conductive zones, at shallow depths of 2-9 m. Pitting carriedout over these zones revealed graphite occurrences at interpreted depth.

5 illus, 2 tables, 4 ref

000200   Radhakrishna B P (NO, , , Email: gsocind@gmail.com) : Small scale mining and rural employment generation : Some new perspectives. J Geol Soc India 2006, 67(4), 419-22.

000199   Puspito N T;Gunawan I (Dep of Geophysis and Meteorology, Inst of Technol Bandung Jalan Ganeca 10, Bandung-40132, Indonesia) : Tsunami sources in the Sumatra region, Indonesia and simulation of the 26 December 2004 aceh tsunami. ISET J Earthquake Technol 2005, 42(4), 111-25.

A total of 19 tsunamis generated by earthquakes occurred in the Sumatra region in the period from 1770 to 2005. About 84% of the tsunamigenic earthquakes have magnitude M_s <62> 6.0 and about 86% of them have focal depth less than 100 km. This characteristic is comparable with the characteristics of tsunamigenic earthquakes in the Pacific region. The empirical relationship between tsunami intensity I on Soloview-Imamura scale and the earthquake magnitude M_s can be written as I = 0.80M_s - 4.18. The tsunamigenic earthquakes in the Sumatra region tend to generate larger tsunami than the ones in the Pacific region where the relationship can be written as I = 1.22M_s - 8.89. A numerical tsunami simulation was performed to model the 26 December 2004 Aceh tsunami by utilizing a method developed by the Tohoku University. In general, the calculated tsunami arrival times were comparable with the observed or reported ones, while the calculated tsunami heights were smaller than the observed ones. Judging from the root-mean-square error values at Sibolga and Belawan tide gauge stations it can be noted that the amplitude of the time series of the calculated tsunami heights were quite different compared to the observed ones. However, their coefficient correlation values were relatively high which may indicate that the shape of the two time series of the calculated tsunami heights were comparable with the observed ones.

11 illus, 23 ref

000198   Prasada Rao G S L H V;Krishnakumar K N (Dept of Agric Meteotology. Coll of Hort, Kerala Agric Univ, Vellanikkara, Thrissur-680 656) : Monsoon onset over Kerala (India): 1870-2004. J Agrometeorol 2005, 7(2), 161-7.

Statistical analysis has been carried out using the long series of data available on onset of monsoon and its rainfall over Kerala, the Gateway of monsoon over India, for the period from 1870 to 2004. There was no change in onset of monsoon (1st June ± 7 days) over a period of time and 28.2 per cent of the years only fell under early or late monsoon years, indicating that the onset of monsoon was normal and ranged from 25th May to 8th June. The early monsoon was seen in 1918 (11th May) and belated monsoon in 1972 (18th June). It also appeared that the monsoon rainfall is likely to be deficit rather than excess if the monsoon is early and no such trend was seen when the monsoon was late. Overall there was a decrease of 131.4 mm in monsoon rainfall over a period of time, indicating a decline of 6.8 per cent against the normal rainfall of 1933 mm. However, the deficit was more evident in monsoon rainfall since last sixty years. Of the 21 occasions between 1871 -2004 when monsoon onset over Kerala was delayed by 7 days or more, 10 cases were associated with El Nino episodes and 3 years with La Nina episodes. Delays/ early monsoon onset occurred preferentially in the year +1 El Nino /La Nina.

2 illus, 3 tables, 10 ref

000197   Peterson C;Yeh H;Chadha R K;Latha G;Katada T (NO, Portland St Univ, Portland, Oregon 97207, U.S.A) : Flood elevation, inundation distance and flow competence of the 2004 Sumatra-Andaman tsunami, as recorded by tsunami deposits in thirteen shore-normal profiles from the Tamilnadu coastline, India. ISET J Earthquake Technol 2005, 42(4), 95-110.

Thirteen shore-normal profiles in South-East India have been surveyed for tsunami deposit evidence of run-up height, flow depth, inundation distance, flow competence, and flow direction from the December 26 Sumatra-Andaman tsunami. Mud lines on buildings were surveyed into timed tide level (swash zone) to establish maximum still-water height, which ranged from 2.3 to 4.4 m mean tide level (MTL). Hanging debris and structural damage were used to establish maximum surge heights of 3.9 to 6 m MTL. Differences between maximum surge height and ground surface yielded flow depths of 1.2 to 3.2 m. Landward flow directions, as recorded by vegetation flop-overs, sand ripples, and debris shields averaged 250°N yielding an oblique wave attack of 30-40° in central study area. Maximum inundation distances of gravel, i.e., shore-normal distance from mid-swash zone, ranged from 30 to 60 m. Maximum sand transport ranged from 90 to 400 m in distance from the shoreline. Sand sheet deposits ranged from 1 to 30 cm in thickness, and included internal stratification, rare pebble and shell clasts. Maximum tsunami flood inundation, based on transported flotsam, ranged from 140 to 800 m in shore-normal distance. Flotsam transport exceeded sand transport by between 15 and 50% of maximum inundation distance in nine profiles. These preliminary reconnaissance observations characterize the recent tsunami inundation from low-to-moderate forcing, i.e, maximum still water 2-4 m MTL, in the low-relief settings of the South-East India coastal plain.

11 illus, 9 tables, 6 ref

000196   Papadopoulos G A;Fokaefs A (NO, Inst of Geodynamics Natn Obs of Athens, Athens-11810, Greece) : Strong tsunamis in the Mediterranean sea: A re-evaluation. ISET J Earthquake Technol 2005, 42(4), 159-70.

Historical documentary sources of the Mediterranean Sea region contain much information about earthquakes and associated phenomena like tsunamis. A catalogue of historical tsunamis generated by earthquakes is compiled. One of the parameters included is the tsunami intensity calculated by several authors in the past on the basis of traditional 6-point tsunami intensity scale. The historical information is re-examined and the intensity of tsunami events is re-evaluated according to the new 12-point tsunami intensity scale introduced by Papadopoulos and Imamura. An attempt has been made to establish quantitative relations between the traditional and the new intensity scales as well as between the tsunami intensity and parameters of the earthquake size like magnitude and intensity.

8 illus, 4 tables, 17 ref

000195   Murty T S;Nirupama N;Nistor I;Rao A D (Dep of Civ Engng, Univ of Ottawa, Ottawa, Canada) : Why the atlantic generally cannot generate transoceanic tsunamis?. ISET J Earthquake Technol 2005, 42(4), 227-36.

For the three oceans with major and concentrated population centers around the coastlines, namely, the Pacific, Atlantic and Indian Oceans, past events as well as numerical models appear to suggest that, while the Pacific and Indian Oceans can support trans-oceanic tsunamis, in general, the Atlantic Ocean cannot. There are seismological and physical oceanographic reasons for this difference in behaviour. It is not that the Atlantic Ocean does not give rise to tsunamis, but they are all generally local and do not impact the whole Atlantic Ocean. This local behaviour of tsunamis in the Atlantic Ocean needs to be taken into account in developing a tsunami warning system.

10 illus, 1 table, 33 ref

000194   Murty T S;Nirupama N;Nistor I;Hamdi S (Dep of Civ Engng, Univ of Ottawa, Ottawa, Canada) : Far-field characteristics of the Tsunami of 26 December 2004. ISET J Earthquake Technol 2005, 42(4), 213-17.

The tsunami of 26 December 2004 in the Indian Ocean not only propagated throughout the Indian Ocean, albeit with varying amplitudes at different coastlines, but also travelled into the Pacific and Atlantic Oceans via the southern ocean route. In this study, the emphasis is on the far-field characteristics, where the tsunami amplitudes are much smaller than those in the Indian Ocean, and are somewhat devoid of local resonance amplification effects as in the Indian Ocean, where the tsunami was generated.

1 illus, 1 table, 8 ref

000193   Mandal M;Mohanty U C (Cent for Atmospheric Sci, Indian Inst of Technol, Delhi, Email: mohanty@cas.iitd.ernet.in) : Numerical experiments for improvement in mesoscale simulation of Orissa super cyclone. Mausam 2006, 57(1), 79-96.

Super cyclone that crossed Orissa coast on 29 October 1999 was the most intense storm in the history of Orissa with 12 coastal districts of the state were battered by winds reaching 250 kmph. The fury of winds continued for more than 36 hours after landfall of the storm. The storm caused huge damage to properties and nearly 10,000 people lost their lives. In the study, extensive numerical experiments are conducted to investigate some important aspects that may lead to the improvement in mesoscale simulation of the storm. The aspects that are addressed here include non-hydrostatic dynamics, model horizontal resolution and parameterization of important physical processes. The mesoscale model MM5 is used to produce 5-day simulation of the storm. The influence of non-hydrostaticity is investigated by simulating the storm with hydrostatic (HS) and non-hydrostatic (NS) dynamics at same resolution (30 km) and with same time step. The storm, in particular its intensity is better simulated with non-hydrostatic dynamics. The importance of incrasing model horizontal resolution is investigated by simulating the storm at 90 km, 60 km and 30 km resolutions with non-hydrostatic dyamics and found to have perceptible impact in simulation of the storm. Numerical experiments also are conducted to find out the best possible combination of the parameterization schemes available in the model for the important physical process cumulus convection, planetary boundary layer (PBL) and radiation.

12 illus, 4 tables, 27 ref

000192   Loe B R;Verma B L;Giri R K;Bali S;Meena L R (NO, India Meteorological Dep, New Delhi-110 003, Email: loe@imdmail.gov.in) : Recent very severe tropical cyclones over the Bay of Bengal: analysis with satellite data. Mausam 2006, 57(1), 37-46.

Shows the impact made by the satellite data in the intensity estimation and track prediction of tropical cyclones of Bay of Bengal. Focused on the recent accomplishment and advances in the remote sensing techniques to optimize the use of satellite data in tracking, formation and movement of cyclonic storms. Two cyclones - firstly the Myammar severe cyclone storm of 16 to 19 May 2004 and secondly the 26 -31 October 1999 Orissa cyclone have been analysed. Satellite based technique using Very High Resolution Radiometer (VHRR) data, scatterometer winds and outgoing long wave radiation (OLR) data in pseudo color around the cyclones have been found to be more useful in predicting formation and movement of cyclonic storms. The study has significantly brought out the difference in formation and movement of the two cyclones formed over the Bay of Bengal.

5 illus, 2 tables, 8 ref

000191   Loe B R;Giri R K;Verma B L;Bali S;Roy S S (NO, India Meteorological Dep, New Delhi, Email: loe@imdmail.gov.in) : Comparative analysis of subjective/advanced objective technique of tropical cyclone intensity estimation. Mausam 2006, 57(1), 159-64.

Dvorak technique operationally used all over the world for estimating the tropical cyclone intensity is based on satellite observations. It involves image pattern recognition based on certain empirical rules along with the analyst interpretation of organized convection. The computer-based algorithm can minimize these subjective judgement discrepancies between different analysis centers estimating the same storm. This modified version is called Advanced Objective Devorak Technique (AODT) and which is applicable for well-developed tropical cycloens. The performance of the AODT is evaluated on three cases of the year 2004 tropical cyclones. Comparative analysis indicates the technique to be competitive with, the Dvorak-based intensity estimates produced operationally by satellite analysts from tropical analysis centers.

12 illus, 3 tables, 10 ref

000190   Koutitas C;Karambas T (Dep of Civ Engng, Aristotle Univ of Thessalonki, 54006 Thessaloniki, Greece) : A computational approach to design codes for tsunami resisting coastal structures. ISET J Earthquake Technol 2005, 42(4), 137-45.

The recent mega-tsunami event on the 26th December 2004, revealed the importance and the necessity of designing "tsunami-resisting" structures. The present study paves a path towards the organization of "design codes" and engineering practices addressing this important issue. A computational model consisting of the nonlinear shallow water equations in the 2DH space, in the presence of an embedded typical building is synthesized and numerically solved by an explicit second order finite difference scheme on a solution domain discretized by a staggered Arakawa "C" grid. The normalized integral of the hydrodynamic loads distributed on the building surface in the direction of the wave propagation is plotted against the normalized length of the structure for various building walls configurations. The importance of the building orientation with respect to the wave propagation and the importance of the openings in the walls are revealed by means of a number of numerical experiments. An experimental verification is pending. The presented numerical tool, in conjunction with the structural resistance analysis of the building walls, leads to operational results as far as the building design specifications are concerned, and mainly in order to resist the expected "design tsunami" and to operate as an "ad hoc" shelter for the people in the vicinity.

6 illus, 7 ref

000189   Kalsi S R;Srivastava K B (NO, India Meteoroligcal Dep, New Delhi, Email: imdsrk@yahoo.com) : Characteristic features of Orissa super cyclone of 29th October, 1999 as observed through CDR Paradip. Mausam 2006, 57(1), 21-30.

An attempt has been made to document the radar observed features of evolution of super cyclone that hit Orissa on October, 1999. Analysis of polar diagrams comprising of hourly PPI images taken between 280800 UTC and 290200 UTC reveals interesting aspects of development of this Super Cyclone in terms of waxing and waning of eye size in relation to intensification process. The smallest radius of maximum reflectivity is in conformity with the colossal death toll observed close to the track of the super cyclone. Structural changes observed through radar images are in conformity with intensity changes as seen through other observing systems.

4 illus, 31 ref

000188   Kalsi S R (NO, India Meteorological Dep, New Delhi-110 003) : Orissa super cyclone. Mausam 2006, 57(1), 1-20.

Orissa was battered by a Super Cyclone Storm on 29 October, 1999 that made landfall near Paradip (43976). The estimated maximum wind speed reached 260-270 kmph in the core area which produced a huge storm surge that led to sea-level elevation of more than 20 feet and took away valuable lives of nearlay 10,000 people. It was accompanied with exceptionally heavy rains whcih led to devastating floods and cut off the State from the rest of the country. An attempt has been made to describe the various features of development and movement of this cyclone through radar and satellite imageries, conventional data and numerical models. Emphasis was laid on the real-time handling of this event, impacts made by the cyclone and the services rendered in relation to disaster management by the State and Central Agencies.

10 illus, 3 tables, 43 ref

000187   Jayanthi N;Prasad S K;Sunitha Devi S (NO, Meteorological Office, Pune-411 005) : Winter season (January-February 2005). Mausam 2006, 57(1), 197-208.

2 illus, 4 tables

000186   Immaculate mary M;Senthamarai kannan K; Suyambulingom C (NO, N.I.College of Engng, K.K. District, Kumaracoil-629 180) : Rainfall-prediction of cyclic changes. J Agrometeorol 2005, 7(2), 241-8.

Rainfall is beyond human intervention, it requires accurate forecast, which is yet to be solved. This attempt exhibits a method to forecast rainfall. Periodic oscillations in the rainfall were observed in the scatter diagram and therefore Harmonic Analysis was used. To justify the validation of the prediction, Markov-transition probability matrix and its powers are used.

2 illus, 4 tables, 9 ref

000185   Gurunadha Rao V V S (Envir Hydrology Grp, Natn Geophys Res Inst, Hyderabad-500 007) : Urban lakes restorations in Hyderabad, India. J appl Hydrol 2005, 18(4), 11-29.

The hydrogeological, geophysical, water quality and groundwater data base collected in three watersheds covering the 5 lakes have been used to construct groundwater flow models. The lake-water and groundwater interaction computed in the model has been used for computation of the lake water budget combining with inflow and outflow measurements on streams entering and leaving these lake. Each lake water budget has been used for design of Sewage Treatment Plants (STPs) on the inlet channels of the lakes for maintaining Full Tank Level (FTL) in each lake. The STPs are designed for tertiary treatment i.e. removal of nutrient load, Phosphates and Nitrates. Through addition of Alum to the influent streams in STPs Phosphates are reduced whereas Nitrates reduction is achieved by sending the treated wastewater from the STP through a wetland before entering the lake. The surplus flows entering the lake have been diverted through surplus contour drains bypassing the lake have been constructed by HUDA. STPs ranging from 2 -10 MLD have been recommended depending the lake water budget of individual lake and surrounding urbanization. Sediment nutrient data has helped for deciding the need for dredging of lake bed for removal of phosphates. The performance of STP on Nadimicheruvu has been also assessed through comparison of nutrient load.

27 illus, 6 ref

000184   Gupta A (NO, Natn Cent for Medium Range Weather Forecasting (NCMRWF), NOIDA, U.P, Email: algi[ta@ncmrwf.gov.in) : Current status of tropical cyclone track prediction techniques and forecast errors. Mausam 2006, 57(1), 151-8.

It has been observed that world-wide rate of reduction of forecast errors was of the order of 1%-2% per year for all time horizons, with most rapid improvement at longer durations (beyond 48 hours). While other basis like Atlantic and Pacific oceans reported greater rate of decline of these errors due to various factors, the trend has been quite modest for Indian region. The only factor responsible for reduction of errors in the region was the greater use of synthetic vortex by operational NWP centrs like India Meteorological Department (IMD) and Natioanl Centre for Medium Range Weather Forecasting (NCMRWF) in their Regional and Global model analyses. The current emphasis of international tropical cyclone research is to achieve greater accuracy of TC track prediction, especially in the short range, by maximizing the use of non-conventional data, meso-scale analysis, use of synthetic data for vortex specification, and the performance of physical parameterization at higher model resolution. The current research and operational emphasis of the ongoing Hurricane WRF project for land falling cyclones, is expected to benefit the Indian region in the years to come. Nevertheless, the Indian region needs to assign higher priority to the greater availability of conventional and non-conventional data and use of advanced data assimilation technique for model analysis besides its concerted efforts on model developments.

2 illus, 6 tables, 35 ref

000183   Grover A K (NO, Geol Surv of India, 15-16, Jhalana Institutional Area, Jaipur - 302004) : Salient features of the ancient gold panning sites and stone grinding implements of Bhukia-Jagpura prospect and adjoining areas, Southeastern Rajasthan. J Geol Soc India 2006, 67(4), 523-31.

The recent find of gold mineralisation in the Precambrians of Bhukia-Jagpura area in southeastern Rajasthan, was based on the identification of native gold flakes in the gossan in close vicinity of old workings. Detailed investigation in the area has brought out the presence of physical evidences of gold extraction from the auriferous ores by ancient prospectors, in the form (i) ancient gold panning sites and (ii) stone grinding implements. The panning sites exhibt special characters in comparison to the sites of commonly known riverside gold panning activites. The stone grinding implements include pestles, mortars and poly-mortars, which however, are similar to those already reported from other parts of India. A widespread presence of these features in Bhukia-Jagpura prospect and adjoining areas indicates towards the existence of a flourishing gold winning industry in southeastern Rajasthan during recent past. Identification of such ancient gold panning sites and implements can form a tool in locating new gold prospects.

21 illus, 1 table, 20 ref

000182   Goswami P;Mandal A;Upadhyaya H C;Hourdin F (NO, CSIR Cent for Math Modelling and Computer Simulation (C-MMACS), Bangalore, Email: goswami@cmmacs.ernet.in) : Advance forecasting of cyclone track over north Indian Ocean using a global circulation model. Mausam 2006, 57(1), 111-18.

Tropiclal cyclones pose a serious and growing threat to many coastal areas world over; there is increasing demand for better accuracy as well as longer range for tropical cyclone forecasts. While the traditional tool for dynamical forecasting of tropical cyclones has been Limited Area Models (LAM), there are reasons to believe that use of Global Circulation Models (GCM) may result in improved representation of cyclone dynamics. Over Bay of Bengal, for example, while some cyclones develop in situ, many result from intensification of low pressure system that travel from the east, implying need for consideration of a large domain. Shows that a relatively new class of Global Circulation Models (GCM), combining the advantages of LAMs and GCMs, can provide both longer range and better accuracy for such critical parameters like track and intensity. For seven cyclones representing different locations, seasons, years and strength, simulated tracks and land-fall locations show, with initial condition more than 5 days ahead and only monthly climatology of sea surface temperature (SST), errors comparable to those from current operational forecast 48 hours in advance.

7 illus, 2 tables, 17 ref

000181   Gokhale V A (NO, Dr. B.N Coll of Archit, Karve Nagar, Pune-411 052) : Analytical study of living environment in the tsunami-affected areas of Tamil Nadu, India. ISET J Earthquake Technol 2005, 42(4), 219-25.

More than 4500 km stretch of the Indian coastline was badly affected by the tsunami on 26th December 2004. The worst affected state Tamil Nadu faced the loss of 7993 lives and destruction of about 123,105 houses. In a developing country like India both socio-economic and climatic aspects largely govern the architectural development as a whole and, consequently, the extent of damage, as far as occurrence of natural disasters is concerned. Presents an analytical study of damage to living environment and damage pattern of the above-mentioned event. It highlights the character of typical settlement pattern in Tamil Nadu and various socio-economic aspects responsible for architectural development to find out the cause of failure of existing building stock. Based on surveys, examines the suitability of various temporary shelters provided to the tsunami victims in order to find out the appropriate approach for the development of a sustainable architecture for the victims. This is indeed imperative for the people who have suddenly lost their entire social, physical and cultural surroundings.

12 illus, 3 tables, 7 ref

000180   Geist E L (NO, U.S. Geol Surv, 345 Middlefield Road, Menlo Park, CA 94025, U.S.A) : Rapid tsunami models and earthquake source parameters: far-field and local applications. ISET J Earthquake Technol 2005, 42(4), 127-36.

Rapid tsunami models have recently been developed to forecast far-field tsunami amplitudes from initial earthquake information (magnitude and hypocenter). Earthquake source parameters that directly affect tsunami generation as used in rapid tsunami models are examined, with particular attention to local versus far-field application of those models. First, validity of the assumption that the focal mechanism and type of faulting for tsunamigenic earthquakes is similar in a given region can be evaluated by measuring the seismic consistency of past events. Second, the assumption that slip occurs uniformly over an area of rupture will most often underestimate the amplitude and leading-wave steepness of the local tsunami. Third, sometimes large magnitude earthquakes will exhibit a high degree of spatial heterogeneity such that tsunami sources will be composed of distinct sub-events that can cause constructive and destructive interference in the wavefield away from the source. Using a stochastic source model, it is demonstrated that local tsunami amplitudes vary by as much as a factor of two or more, depending on the local bathymetry. If other earthquake source parameters such as focal depth or shear modulus are varied in addition to the slip distribution patterns, even greater uncertainty in local tsunami amplitude is expected for earthquakes of similar magnitude. Because of the short amount of time available to issue local warnings and because of the high degree of uncertainty associated with local, model-based forecasts as suggested by this study, direct wave height observations and a strong public education and preparedness program are critical for those regions near suspected tsunami sources.

3 illus, 66 ref

000179   Fernandez-Arce M;Alvarado Delgado G (Cent for Geophys Res, Univ of Costa Rica, San Pedro, Costa Rica) : Tsunamis and Tsunamis prepardness in Costa Rica, Central America. ISET J Earthquake Technol 2005, 42(4), 203-12.

The Costa Rican coasts are at risk of local tsunamis. On both Pacific and Atlantic sides of Costa Rica there are coastal segments characterised by a flat relief, which increases the vulnerability of the coastal communities. In addition to tsunamis originating in the Middle American Trench (MAT), Costa Rican communities are at risk of a local tsunami generated by an earthquake in an undersea thrust fault system that runs along the Caribbean coasts of Costa Rica and Panama (NPDB). Furthermore, recent bathymetric studies reveal evidence of prehistorical submarine landslides in the Pacific Ocean capable of generating large tsunamis. The Golfo Dulce tsunami in 1854 in the Pacific and the Bocas del Toro tsunami in 1991 in the Caribbean are the real evidence of the hazard in the country. The University of Costa Rica is working on the implementation of the Tsunami Hazard Mitigation Program.

6 illus, 2 tables, 22 ref

000178   Elango L (Dep of Geol, Anna Univ, Chennai) : Numerical modelling-an emerging tool for sustainable management of aquifers. J appl Hydrol 2005, 18(4), 40-6.

Groundwater modelling has been widely used as a management tool, since the development of digital computers and appropriate numerical models. These models solve the basic partial differential equations that govern the flow of groundwater and solute transport through the saturated and unsaturated porous medium. Models solve the equations of more complex hydrogeological problems involving aquifer heterogeneties, anisotropic aquifer properties and complicated boundary conditions. Groundwater models are of several categories developed for specific purposes. Flow and solute transport problems vary in 2 or 3 dimensions. Groundwater flow and solute transport model have widely used by many researchers to solve numerous problems related to groundwater. Groundwater modelling is an effective management tool to sustainably manage the groundwater resources.

6 illus, 4 ref

000177   Dixit A J;Yadav S T;Kokate K D (NO, Dr. Balasaheb Sawant Konkan Krishi Vidyapeeth (DBSKKV), Dapoli-415 712) : Variability of rainfall in Konkan region. J Agrometeorol 2005, 7(2), 323.

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000176   Das G;Ray S S (Agro-ecology and Mgmt Div, ARG Space Applic Cent (ISRO), Ahmedabad-380 015) : Comparative evaluation of two weather generator for Punjab. J Agrometeorol 2005, 7(2), 231-40.

Weather generators (WG) are computer models that generate synthetic series of daily or sub-daily resolution weather data at a site conditional on the statistical features of the historically observed climate. In the study, two WGs, i.e. ClimGen and LARSWG were compared to evaluate their suitability for the area of study, i.e. Amritsar weather station of Punjab. Twenty years of daily data of rainfall, maximum and minimum temperature was used as input and six years' data was used for validation. Evaluation was done on the basis of RMSE (Root Mean Square Error) and r² value, between generated and actual data. Both models generated temperature data very close to actual with RMSE ranging between 0.69 to 3.15 and r² ranging from 0.89 to 0.99. However, error was high for rainfall generation. In most of the cases, LARSWG provided better accuracy than ClimGen in generating weather data.

2 illus, 3 tables, 13 ref

000175   Bhaskar Rao D V;Hari Prasad D (Meteorology and Oceanography Dep, Andhra Univ, Visakhapatnam, Andhra Pradesh) : Numerical prediction of the Orissa super cyclone (1999) : sensitivity to the parameterisation of convection, boundary layer and explict moisture processes. Mausam 2006, 57(1), 61-78.

Numerical prediction of the movement and intensification of the Orissa Super Cyclone (1999) has been studied using PSU/NCAR MM5. Sensitivity experiments were made to study the role of the parameterisation schemes of convection, planetary boundary layer and explicit moisture schemes. The model is designed to have three interactive domains with 90, 30 and 10 km horizontal resolutions covering the Bay of Bengal region. The initial fields and time varying boundary variables and sea surface temperatures at 12 hour interval are provided from NCEP FNL data available at 1° resolution. Three groups of experiments were performed to study the sensitivity of the cyclone track prediction and intensification to the schemes of convection, planetary boundary layer and explicit moisture processes. The results indicate that convective processes play an important role in the cyclone track prediction and the scheme of Kain-Fritsch 2 produces the best track and the planetary boundary layer processes control the intesification with the scheme of Mellor-Yamada producing the strongest cyclone. The explicit moisture processes modulate the movement of the cyclone, which may be due to the fine resolution of the 10 km for the innermost domain. The mixed-phase scheme in combination with Kain-Fritsch 2 and Mellor-Yamada produce the best simulation in terms of the track as well as intesification.

13 illus, 2 tables, 25 ref

000174   Bera A;Bhattacharya B B;Shalivahan (NO, , , Email: aparnaapar_na@yahoo.com) : 2D Tomographic imaging over mineralised zones using self-potential data. J Geol Soc India 2006, 67(4), 447-58.

Self-potential (SP) anomalies for graphite and other ore bodies have so far been interpreted quantitatively by classical approach only, i.e. determination of parameters like depth to the top of the body, dip etc. Using the concept of charge occurrence probability (COP) function, two-dimensional tomographic images are presented for three mined-out graphite deposits of Balangir district, Orissa and a sulphide deposit of Kayar, Ajmer district, Rajasthan. These deposits were located earlier on the basis of SP anomalies. Trend of the ore bodies were obtained by mise-a-la-masse method. The anomalies in each of the two areas - Bender and Behermunda - were over single graphite ore body only. The anomaly over the third area, i.e. in Berni, located three graphite deposits: (i) second ore body of smaller size located 200 m southeast along the strike of the main deposit, and (iii) a small deposit situated 50 m southwest of the main body. Two-dimensional imaging in the tomoplanes clearly define the single ore bodies in Bender and Behermunda as well as all three ore bodies in berni delineating the ore bodies along strike as well as in depth extent. the sulphide ore body in Kayar is yet to be delineated by large scale drilling but imaging of the ore bdoy agrees well with the available drilling result in the area. The results shows that the imaging technique delineates the ore body and, thereby, provides information for better mine planning for the deposits with optimum drilling. The method is recommended for imaging all the ore bodies generating SP anomaly.

15 illus, 22 ref

000173   Bansal A R;Dimri V P;Sagar G V (NO, Natn Geophys Res Inst, Uppal Road, Hyderabad - 500 007) : Quantitative interpretation of gravity and magnetic data over southern Granulite terrain using scaling spectral approach. J Geol Soc India 2006, 67(4), 469-74.

In frequency domain, interpretation of gravity and magnetic measurements was carried out by the spectral method and its variants. The spectral method assumes the source distribution as white noise. Whereas the detailed analysis of borehole data from several areas reveal that physical properties such as density, susceptibility, reflectivity sequences etc. follow a scaling distribution of sources is incorporated in spectral method and the new approach is known as the scaling spectral method. This method is applied to the gravity and magnetic data of Kuppam-Palani geotransect in southern granulites of southern India. The depth values calculated for the Kuppam-Palani transect agree well with the seismic study. The deviation in the value of the scaling exponent for mid-crustal layer shows the differing nature of the crust for Kuppam-Bhavani and Kolattur-Plani sections of the Kuppam-Palani transect. Further, different values of scaling exponent obtainable from gravity and magnetic data for the same depth indicate that sources for gravity and magnetic anomalies are different.

5 illus, 21 ref

000172   Ballukraya P N (Dep of Appl Geol, Univ of Madras, Chennai) : Over-expoltation of groundwater in hard rock areas: problems and perspectives. J appl Hydrol 2005, 18(4), 1-10.

Groundwater abstraction has increased to such an extent that in several areas of the country, well failures have become chronic. In certain over-exploited blocks, the well depths are nearing the critical depths, beyond which it will be impractical to drill borewells. The lowering groundwater levels have created difficulty even in meeting out domestic water supply in such areas. The socio-economic fallout has been very tragic in southern India due to the financial burden imposed on the farmers by the repeated failure of borewells. While artificial recharge of groundwater does offer some hope in remedying the situation the alarming decline in well yields indicates that the present abstraction is simply not sustainable and some long-range and hard decisions are needed to be taken in order to regenerate the health of groundwater environment. It is time that the problem is perceived in the background of environmental economics rather than as a pure resource crunch.

5 illus, 10 ref

000171   Ashrit R G;Das Gupta M;Bohra A K (NO, Natn Cent for Medium Range Weather Forecasting, NOIDA-201 307, Email: raghu@ncmrwf.gov.in) : MM5 simulation of the 1999 Orissa super cyclone : impact of bogus vortex on track and intensity prediction. Mausam 2006, 57(1), 129-34.

NCAR/PSU MM5 mesoscale model (Grellet al, 1995) has been used to simulate the super cyclone that struck the Orissa coast on 29th October 1999. The model makes use of the operational NCMRWF T 80 analysis as initial and boundary conditions and is integrated up to 72 hr for producing 3-day forecast of the storm. The aim of the study is to assess the impact of bogus vortex on track and intensity prediction.

3 illus, 2 tables, 10 ref

008024   Wadhwa R S;Ghosh N;Subba Rao C (NO, Central Water and Power Research Station, Khadakwasla, Pune-411 024, Email: wadhwa_rs.cwprs@nic.in) : Empirical relation for estimating shear wave velocity from compressional wave velocity of rocks. J Indian Geophys Union 2010, 14(1), 21-30.

In situ shear wave velocity is one of the most important parameters for evaluating dynamic elastic moduli and needs special energy sources for generation and receivers for detection. Identification of shear wave phase on a seismic record needs skill as it is not the first wave to arrive and is usually embedded in surface waves. To estimate shear wave velocity for site characterization and for predicting the in situ quality of rock, empirical relations were proposed by Carroll (1969) to predict shear wave velocities from compressional wave velocities of rock samples. His empirical relation was used on the actual field data and the estimated shear wave velocities were compared with in situ velocities measured using cross-hole seismic technique. The shear wave velocities measured at four nuclear power plant sites were used to generate the correlation between compressional and shear wave velocities. A power fit model with a regression coefficient of 0.84 was developed. This correlation is valid for rocks having compressional wave velocity ranging from 4000 m/sec to 6000 m/sec and Poisson's ratio between 0.22 and 0.28. The proposed relation is based on 185 data pairs of in situ compressional and shear wave velocity measurements conducted at four nuclear power project sites. The sites with different host rocks are: Kota (Rajasthan), Kaiga (Karnataka), Tarapur (Maharashtra) and Kakrapar (Gujarat). The empirical relationship proposed in this paper is first of its kind in India. The proposed empirical relation can be used to predict shear wave velocities at similar rock sites anywhere in India.

8 illus, 21 ref

008023   Viswanathan S;Surya Prakash Rao K (NO, , Flat B-203, Block-B, United Avenue Apartments, South End, 7-1-29, Ameerpet, Hyderabad-500 016, Email: ksprao1939@yahoo.co.in) : Wavelength-dispersive x-ray fluorescence spectrometric determination of Rb, Sr, Y, Zr, and Nb in granitic rocks using a gas-flow proportional counter and vacuum path. J appl Geochem 2009, 11(2), 132-9.

The conventional method for determining the petrogenetically significant trace-elements, Rb, Sr, Y, Zr, and Nb, in granitic rocks by wavelength-dispersive x-ray fluorescence spectrometry (WDXRFS) uses a scintillation counter, air path and fine collimator. This paper demonstrates that these trace-elements can also be determined accurately, precisely and rapidly using a gas-flow proportional counter, vacuum path and coarse collimator. The accuracy is excellent (within 3.4%). The precision is also excellent (within 3.7% for Rb, Sr, Y, and Zr and within 5.0% for Nb). The limits of detection for Rb, Sr, Y, Zr and Nb are 2.6 ppm, 2.9 ppm, 2.4 ppm, 8 ppm and 2.6 ppm, respectively. Except for Zr, these values compare excellently with the values of 1.9 ppm, 1.9 ppm, 1.0 ppm, 2.4 ppm and 0.5 ppm for Rb, Sr, Y, Zr and Nb, respectively, obtained by the conventional method. The time taken for determining Rb, Sr, Y, Zr and Nb in a batch of twentyfour granitic rock samples, for a replication of four analyses per sample, by one operator using a manual WDXRF spectrometer, is only sixteen hours.

5 illus, 2 tables, 1 ref

008022   Syrya Prakash Rao K (Applied Geochemistry Dep, Osmania Univ, 1-2-7/1, Kakatiyanagar, Habsiguda, Hyderabad-500 007, Email: ksprao1939@yahoo.co.in) : Establishment of a department of applied geochemistry in the osmania university and the indian society of applied geochemists: significant milestones in the growth of applied geochemistry in India. J appl Geochem 2009, 11(2), 140-65.

The establishment of the Department of Applied Geochemistry (DAG) in the Osmania University, Hyderabad, and the Indian Society of Applied Geochemists (ISAG) with headquarters at Hyderabad are significant milestones in the growth of Applied Geochemistry in India. This paper traces the path leading to the establishment of DAG, outlines the academic programmes in DAG, lists the research projects undertaken by DAG, highlights the major discoveries made as a result of the research, and focusses on the aims, objectives, and achievements of ISAG.

28 illus, 8 ref

008021   Sharma M L;Kumar R (Earthquake Engineering Dep, Indian Institute of Technology, Roorkee-247 667, Email: mukutfeq@iitr.ernet.in) : Estimation and implementations of conditional probabilities of occurrence of moderate earthquakes in India. Indian J Sci Technol 2010, 3(7), 807-16.

The conditional probabilities of occurrence of moderate earthquakes considering the likelihood of occurrence of the next large earthquake in the seismically active regions in India where the last such occurrence has crossed the return periods. The conditional probabilities have been estimated using Weibull distribution. The estimations have been carried out for 24 seismogenic sources earmarked in the Indian subcontinent. The cumulative and conditional probabilities have been interpreted with respect to the last earthquake occurrence in the time intervals of 15 and 50 years. Most of the seismically active regions are found to have lesser recurrence of earthquakes with specific magnitudes as compared with the estimations being carried out using classical probabilistic seismic hazard assessment approach.

3 illus, 3 tables, 53 ref

008020   Sarma A A L N;Sivaram B (Meteorology and Oceanography Dep, Andhra Univ, Visakhapatnam-530 003, Email: aalnsarma_met@rediffmail.com) : Weekly growing periods in extremities over India-monsoon period. J Indian Geophys Union 2010, 14(1), 57-66.

India, being an agrarian country, the studies on Growing periods plays an important role in crop growth and performance in particular during the ocean atmospheric interactions such as ENSO/LNSO, which modulate the south west monsoon of India. The present paper addresses not only the growing period of India and selected stations from the Moist and Dry climates of India during the monsoon period of 1951-80, 1981-91, 1992-98, on a weekly basis, but also the affectivity of ocean atmospheric interactions such as ENSO/LNSO and SST of Nino 3 region for the ENSO year (1987) and LNSO year (1988) through the revised water balance model. The trend analysis of growing periods with respect to the march of SOI and SST of Nino 3 region for the period 1992-98 has been presented.

1 illus, 4 tables, 18 ref

008019   Sarkar A;Raju M M;Anil Kumar (NO, National Institute of Hydrology, Roorkee-247 667) : Sediment runoff modeling using artificial neural networks. J Indian Wat Resour Soc 2010, 30(1), 39-45.

The magnitude of sediments transported by rivers is a major concern for the water resources planning and management. The methods available for sediment estimation are largely empirical, with sediment rating curves being the most widely used. In this study, Artificial Neural Network (ANN) technique has been applied to model the sediment-discharge relationship of a river. Daily data of sediment concentration and discharge of Pranhita River (a sub-basin of Godavari River) in India have been used. A comparison has been made between the results obtained using ANNs and sediment rating curves. The sediment load estimations in the river obtained by ANNs have been found to be significantly superior to the corresponding classical sediment rating curve ones.

3 illus, 2 tables, 14 ref

008018   Reddy A G S;Reddy M R K (NO, Central Ground Water Board, Southern Region, Hyderabad, Andhra Pradesh, Email: sugrive_59@rediffmail.com) : Hydrogeochemistry of potential groundwater zones in Hyderabad city, Andhra Pradesh, India. J appl Geochem 2009, 11(2), 347-62.

Groundwater exploration is carried out in central part of Hyderabad city between North latitude l7"19'-17"30' and East longitude 78"23'-78"30' comprising about 200 sq km area. The area is underlain by the Archaean crystalline complex comprising peninsular gneisses, younger intrusives and older metamorphic rocks. These rocks exhibit fractures, faults, joints, shear planes and minor folds. Ten bore wells were drilled down to a depth ranging from 131.70 to 203.00m. Deep potential fractures are encountered in the western parts between 115-173m. In the eastern parts of the city, the fractures are found to occur down to a depth of only 70m. There is wide variation in water levels of the bore wells due to elevation difference and varied structural disposition. The discharges of successful wells vary between 2.11 and 6.911ps at drawdown ranging from 7.60 to 20.60m, whereas the transmissivity varies from 8.85 to 201.6 sq m/day. Chemical quality of water is poor as some parameters are beyond permissible limits of the BIS drinking water standards. Ground water in the eastern part, which is a topographic low area having gentle slope is the most polluted having high contents of total hardness, Ca⁺², Mg⁺² Na⁺, Cl^-, SO₄^-2 and NO₃^-. These wells being located in high density of human habitation areas had resulted in large-scale contamination of saturated shallow fractures due to dumping of organic waste, leakage of sewerage lines and very poor drainage system. Fluoride content is high (1.62-2.6) in waters of western part, which is an elevated area with steep gradient. Pink granites, which are rich in fluorite and apatite minerals, had resulted in dissolution and absorption of fluorides into ground water. Accumulation of ground water in these fractured pink granite rocks for long period, undisturbed without extraction and a limited recharge could have led to higher fluoride concentration.

7 illus, 5 tables, 26 ref

008017   Razdan P N (NO, KIIT Univ, Bhubaneswar) : Role of geochemistry in mineral exploration. J appl Geochem 2009, 11(2), 310-14.

Geochemistry is a powerful integration of knowledge and technique in mineral exploration programs. It is a most productive tool available for understanding reserve of any mineral deposit and also to explore the new resources. Hawkes (1957) defines geochemical prospecting as a method of mineral exploration based upon systematic measurement of one or more chemical properties of a naturally occurring material. The purpose of the measurements is the discovery of a geochemical "anomaly" or area where the chemical pattern indicated the presence of Ore in the vicinity. The primary role of geochemical exploration is to find an area that is anomalous in the desired mineral, known to be associated with the type of mineralization sought. Many important mineral deposits are associated with sedimentary rocks, as syngenetic deposits, while with metamorphosed rocks, as syngenetically and epigenetically. They are formed from aqueous solutions at a temperature which is not more than a few hundred degrees which is predominantly water having dissolved cations and anions. The physical condition of water, its solute chemistry and pathway are all controlled by geological processes operating at not more than a few kilometers from the surface of the earth. In the discovery of any mineral deposit, geochemistry plays an important role in understanding the concept of mobilization, concentration, transpiration and deposition of ore elements all through an aqueous solution in which the energy of these processes is either the internal heat of the earth or solar energy. In the ore solutions, hydrogen ion activity, electron activity and anion concentration have significant role to play and as such formation of any ore solution requires a good understanding of the physical chemistry of water in addition to the geology and geochemistry of rocks. Certain elements serve as geochemical pathfinders in the exploration for the mineral deposits. Archean gold ores are typically enriched in gold with variable elements in Ag, As, W, Sb, and Bi. If anomalies of these elements are found, which can substantiate the geological evidence, there appears to be reasonable chance of locating gold. In the recent exploration for gold in India, geochemical methods have not been used much, except in few cases, in comparison to large number of areas that have received attention by trenching and drilling. In addition, knowledge of chemistry of transport and deposition of As, Sb, Hg, Th and Te, which are frequently associated with gold, enhances our understanding of the processes involved. A comprehensive interpretation of noble metals geochemistry is more complete, if additional abundance data of these pathfinder elements are also available. Regional geochemical exploration has traditionally involved use of stream sediments to target potentially mineralized catchments. Regional surveys may use low sampling densities such as one sample per 100 square kilometers. However, under National Geochemical Mapping Programme (NGCMP), the Geological Survey of India has been carrying out regional geochemical surveys on a systematic grid of one sample per square kilometer for 67 elements with reasonably excellent detection limits. Stream sediment geochemistry is the best representative media for the exploration in virgin area where bed rock is either not exposed and where the geological set-up is very inhomogeneous. There are evidences from China, Russia, Canada etc. where geochemical exploration through stream sediment geochemistry has brought several new mineral deposits. Further, the native elements that occur in trace concentrations such as gold, diamonds etc. are best represented in stream sediments. Areas which are covered by transported soils, alluvium, colluviums or are disturbed too much by human activity (roads, rail, farmland), may need to be drilled to a shallow depth in order to sample undisturbed or unpolluted bedrock. The bedrock is the ultimate source of mineral and there are several indicator minerals and mineral associations. For example, arsenopyrite is an indicator for gold and diamond; Ni, Cr, Co and PGE are associated with basic rocks.

15 ref

008016   Raina A;Pande H C;Sharma P;Singh H;Singh R R (Geochemistry Group, KDMIPE, ONGC, Dehradun-248 195, Email: ashokraina59@redifmail.com) : Geochemistry of coal bed gases from Gondwana basins, India. J appl Geochem 2009, 11(2), 300-9.

In present time, the environmental requirements of energy sources have advanced to the forefront along with their economic demands. Consequently, the role of natural gas along with unconventional resources of natural gas has increased sharply in recent years. Some of the prospective areas of these unconventional resources are CBM gases. The coal bearing formations of India occur in two distinct geological horizons in the lower Gondwana(Permian) of West Bengal, Jharkhand, Bihar, MP and Maharashtra and the Tertiary sediments (Eocene-Oligocene) of north-eastern India, Rajasthan, Gujarat and Jammu and Kashmir. The objective of this study is to unravel the molecular composition and origin of the coal bed gases found in Gondwana Basins of India. Barakar Formations, which is the chief contributor of the quality coal seams in most of the coal fields confined to the Permian Gondwana basins, has an estimated coal reserves of about 200 billion metric tones with respect to CBM exploration. The desorbed gas samples from some of the potential areas like Jharia, Bokaro, North Karanpura and Raniganj of Damodar valley in Mahanadi-Bengal-Purnea Basin have been analyzed for their chemical and stable carbon isotopic composition to probe into the coal bed methane potential of this area. Study reveals that the gases desorbed from the cores of coal seams have appreciable amount of methane, more than 70% in most of the cases. The gases have been genetically characterized by stable carbon isotopic values of methane varying from -69 to -22.7%. The isotopic values are indicative of varying proportion of biogenic as well as thermogenic gases generated during coalification process. The geochemical investigation of CBM gas samples in Indian Gondwana has been further extended to central part that is Satpura valley (MP) and Wardha valley (Maharashtra). The compositional analysis of gas samples collected from Satpura is indicative of moderate to high concentration of methane (<126>57% to 94%) in the gas samples desorbed from the cores, with N₂ content varying from 4% to 32 % and CO₂ from 1% to 10%. Small content of C₂+ is also present. The stable carbon isotope data of methane (-52.2 to -41.5%) in the samples of CBM gases indicate that the gases are of thermogenic origin with moderate maturity of coal seams. The chemical composition of CBM gases of Wardha valley reveals that they are devoid of any hydrocarbon gases. The concentration of nitrogen and oxygen is similar to that of atmospheric air. The study gives an insight into the origin of these gases and also a scope to delineate the CBM potential of Gondwana coals in these areas.

8 illus, 7 ref