010605   Saran A K (Engine Div, Hindustan Aeronautics Limited, Koraput, Odisha, India) : Manufacturing of single crystal blade casting for aero engines. SGAT Bull 2014, 15(2), 57-64.

Something exciting has been happening during these last several years in the field of aero engine blade castings. Initial development was polysrystal castings and then came DS (Directionally solidified) castings and the latest one is single crystal castings. A new precision casting technique, based on directional solidification, which imparts significantly improved ductility and thermal shock resistance to high temperature creep resistant, nickel-base super alloys, has been carried through from research to production. This controlled solidification technique has been used to produce single crystal gas turbine components. The improvement in physical properties is achieved by controlling the solidification process to produce a complete single crystal throughout the part, with a preferred [001] crystallographic orientation. This single crystal structure and orientation is established parallel to the major stress axis of the part with the use of a "seed crystal". HP turbine blade is cast by this method. The Single Crystal (SX) castings are produced basically by keeping the molten metal in the mould in the liquid stage itself and allow it to solidify in the desired manner. In the conventional castings the molten metal starts solidification as soon as it comes into contact with the mould walls. This is avoided in case of SX castings. The mould is kept at high temperatures (1500-1600 °C), almost close to the pouring temperature, and then solidification is allowed to start at a predetermined place, usually the bottom of the mould. Solidification starts at the 'starter' at the bottom, which is a Ni-W button (there is provision in the shell to place this). Every shell has 6 blades. 8 coatings form the ceramic shell. The 'starter' is checked for its crystallographic orientation before placing in the mould.

illus

010604   Santharam A (Indian Bureau of Mines, , , Email: asantharam33@gmail.com) : Geotechnical investigation - a tool for deciding mining method for chromite deposites in Odisha. SGAT Bull 2014, 15(1), 60-6.

Chromite deposits of Sukinda valley, Odisha are of strategic importance for the development of ferro-alloy industries. Majority of the chromite production comes from two important chromite belts, namely the Baula-Nuasahi belt and Sukinda ultramafic complex. In terms of rock strength properties, the host rocks and ore body in Baula-Nuasahi are hard and compact, with some structural defects and majority of chromite is produced by underground mining methods. Whereas, in the case of Sukinda valley deposits, both the wall rocks and ore body are weak, highly weathered and are being mined by opencast method. As most of the working mines in Sukinda valley almost reached its economic pit limit, there is an immediate need to convert the opencast workings to develop further as underground mines. The chromite ore bodies of Sukinda area were proved up to depth of 270m. Some major mining companies, working with common lease boundary, are planning for underground mining operations due to the space constraint for dumping, slope instability and high volume of stripping ratio, which necessitate the exploitation of remaining reserves at depth. To overcome such problems, the basic step is to conduct the detailed geo-technical investigations to avoid any unexpected surprises during mine development and stoping. The geo-technical investigations include mapping of existing mined out benches using scan line surveys, geo-technical drilling and logging of cores for the estimation of RQD, structural discontinuities, testing of cores for material properties followed by performing numerical modeling to evolve a suitable stoping method and excavation geometry. The paper deals with the results of the geo-technical investigations carried out for the planning and design of excavations, design of stope parameters were evolved based on the geo-mining conditions.

5 illus, 5 tables, 9 ref

010603   Sahoo B C;Chakraborty T K;Mohanty R K;Suresh Kumar T S (Natural Resource Div, Tata Steel Limited, , Email: bc.sahoo@tatasteel.com) : Application of geochemical exploration technique for identification of sub-surface manganese mineralisation - a case study from Joda West iron & manganese lease of Tata Steel Limited, Odisha. SGAT Bull 2014, 15(1), 46-56.

Geochemical exploration is one of the advanced tools in unravelling the subsurface ore body to facilitate in generating drill target for testing. This technique is gaining significance over other tools of exploration like Remote Sensing which may not reveal dimension of the subsurface occurrences of minerals. This method, adopted as a geological technique since ages, can verify anomalous ore bodies in better way than ground or airborne EM survey. The surface geochemical signature of each mineral deposit is unique in some respect owing to differences in geological, geomorphological and environmental settings; although, many similarities in dispersion characteristics may be discerned over a vast expanse / area, either generically for many ore minerals or specifically for any one. Geochemical models are made to illustrate the nature and origin of the surface expression of mineralization. In regolith-dominated terrains, the models must account for relict features as well as active processes to indicate the nature of geochemical anomalies, element associations, dispersion mechanisms and host rocks. The surface geochemical exploration may be very much useful in identifying the subsurface occurrences of manganese ore bodies because of the nature of mineralisation. Manganese ores of Joda region in Odisha state of India occur as lenses and isolated pockets associated with banded iron formation by the process of remobilisation and supergene enrichment. To understand the dispersion pattern of manganese mineralisation at Joda region which is mostly secondary in nature, the geochemical distribution of manganese in in-situ soil horizon has been taken into consideration. For this, the primary dispersion pattern of manganese in subsoil horizon (B horizon) has been studied from Joda West Iron & Manganese lease area of Tata Steel limited located near Joda in Keonjhar district of Odisha. . The soil samples have been collected with the help of conventional augers from a depth of 1-3ft. The response of manganese assay values have been compared with the threshold value of manganese in this area and their distribution pattern have been prepared. Accordingly, the anomalous zones for manganese have been identified and validated by Reverse Circulation (RC) drilling. The results of RC drilling is evident that some of the anomalous zones as per positive geochemical responses correspond to sub surface manganese mineralisation at few places. Hence, the use of geochemical sampling technique reflects vista of probable manganese mineralisation in any virgin area in such metallogenic Province.Summing up, this paper illustrates successful adoption of geochemical exploration method for identification of concealed subsurface manganese ore bodies.

8 illus, 1 table, 15 ref

010602   Sahai A K;Sharmila S;Abhilash S;Chattopadhyay R;Borah N;Krishna R P M;Joseph S;Roxy M;De S;Pattnaik S;Pillai P A (NO, Indian Institute of Tropical Meteorology, Dr Homi Bhabha Road, Pashan, Pune-411 008, Email: sahai@tropmet.res.in) : Simulation and extended range prediction of monsoon intraseasonal oscillations in NCEP CFS/GFS version 2 framework. Curr Sci 2013, 104(10), 1394-1408.

The present study investigates the role of ocean-atmosphere coupling in improving the simulation and extended range prediction skill of the monsoon intraseasonal oscillations (MISOs) using the NCEP CFS (version 2) vis-…-vis its atmospheric component GFS (version 2) forced with bias-corrected sea-surface temperature (SST) derived from CFS. Though the CFS free-run analysis shows dry bias over Indian land as compared to GFS, the interactive air-sea coupling in CFS has considerably improved the simulation of large-scale dynamical fields, SST-rainfall relation-ship, and the northward propagation of the MISOs with respect to GFS. However, the improvement of MISO simulation in CFS over GFS has not necessarily guaranteed the improvement of real-time extended range prediction during 2011 and 2012. CFS shows better skill over GFS (forced with bias-corrected CFS derived SST) at pentad lead4. The phases of MISOs are better predicted in GFS and the amplitude prediction skill is marginally improved in CFS. The present study also advocates the need of probabilistic category (active, normal or break) forecast at extended range.

15 illus, 69 ref

010601   Reddy D V;Nagabhushanam P;Ramesh G (NO, CSIR-National Geophysical Research Institute, Uppal Road, Hyderabad-500 007, Email: dvreddy.ngri@gmail.com) : Turnover time of Tural and Rajvadi hot spring waters, Maharashtra, India. Curr Sci 2013, 104(10), 1419-24.

Sixty hot springs are spread over 18 regions in the west coast of Maharashtra, India. The area is covered by Deccan Basalts. Periodic water sampling was done for more than 5 years from Tural and Rajvadi hot springs along with waters from other deep wells for hydrochemical and isotopic analyses to study the relation between seismicity and hydrochemistry. Residence time of hot spring waters was estimated using the ^{14C dating. Though the studied hot springs are located in an active seismic region, their hydrochemical, isotopic and temperature signatures did not indicate any major change during the period of the experiment. A comparison with the data collected by GSI three and a half decades ago indicates no longterm change in the hydrochemistry and temperature. Lack of long-term change in hydrochemistry reveals no major effect of seismicity on these geothermal waters. Radiocarbon dating of these two hot spring waters indicates relatively more turnover time for Tural spring (3080±40 years BP) than the Rajvadi (1720 ±45 years BP). The trace element characteristics of the spring waters are close to those measured on waters of granitic terrains, thus indicating the circulation of meteoric water through the granitic basement, before its discharge in the form of thermal springs in the Deccan Trap terrain.}

4 illus, 2 tables, 16 ref

010600   Rath P C (NO, CSIR Institute of Minerals and Materials Technology, Bhubaneswar-751 013) : Acid coal mine drainage. SGAT Bull 2014, 15(2), 7-25.

Mining of coal is carried out in many parts of the world because of its large demand as an important industrial commodity. Exposure of coal and the associated minerals to the atmosphere because of mining results in the weathering of some of the constituent minerals contaminating the water regime in and around the mining area by the weathering products. The weathering of different sulfide minerals particularly pyrite, a common metallic mineral constituent in coal deposits, leads to the generation of acid which can contaminate mine drainage water and adversely affect the environment in the long run. Assessment of the acid generation phenomenon and prediction of mine drainage characteristics are helpful in deciding suitable mitigation measures to combat the environmental effects. This paper attempts to present a comprehensive picture of acid coal mine drainage phenomenon with respect to the genesis of the problem, assessment and prediction of mine drainage quality and, the approaches towards prevention and mitigation of the problem.

3 tables, 33 ref

010599   Rajendran K;Sajani S;Jayasankar C B;Kitoh A (NO, CSIT - Fourth Paradigm Institute (CSUR 4PI), Bangalore-560 037, Email: rajendrank@hotmail.com) : How dependent is climate change projection of Indian summer monsoon rainfall and extreme events on model resolution?. Curr Sci 2013, 104(10), 1409-18.

Advances in climate modelling now provide the oppor-tunity for utilizing global general circulation models (GCMs) at very high-resolution for projections of future climate and extreme events. Diagnostics of global atmospheric GCM simulations at different horizontal resolutions of 20, 60, 120 and 180 km reveals the marked skill of 20 km mesh GCM (MRI-AGCM3.2S) in capturing regional characteristics of climatological summer monsoon rainfall over India and its frequency distribution, and mean annual variation of rainfall over most of the homogeneous regions of India. Future projections by time-slice simulations of MRI-AGCM3.2S under global farming scenario show widespread but spatially varying increase in rainfall over interior regions of peninsular, west central, central northeast and North East India (~5-20% of seasonal mean) and significant reduction in orographic rainfall over the west coast (~10-15%, consistent with the recent observed trends). MRI-AGCM3.2S projects spatially heterogeneous increase in warm days and extreme hot events (highest decile) over India. Projected changes in extreme rainfall events (above 95 percentile) show intensification of extreme rainfall over most parts of India by the end of the century with opposite change over the west coast. Ultra-high-resolution is found to be crucial not only for realistic mean summer monsoon simulation, but for achieving useful future projections of Indian monsoon and extremes. At lower resolution, the simulations fail to capture the observed characteristics of present-day monsoon rainfall and its spatial heterogeneity, and projections lack useful regional climate information. Thus, consideration of fine-scale processes are critical for reasonable probabilistic projection of regional-scale climate change

8 illus, 32 ref

010598   Rajendran C P;Andrade V;Sanwal J;Kurian J; Jena B (Centre for Earth Sciences, Indian Institute of Science, Bangalore-560 012, Email: cprajendran@ceas.iisc.ernet.in) : Constraining large earthquakes along the Andaman trench using deepwater turbidites: prospects and challenges. Curr Sci 2013, 104(10), 1300-7.

The 2004 Sumatra-Andaman earthquake was unprecedented interms of its magnitude (Mw9.2), rupture length along the plate oundary (1300 km) and size of the resultanttsunami. Since 2004, efforts are being made to improve the understanding of the seismic hazard in the Sumatra-Andaman subduction zone in terms of recurrence patterns of major earthquakes and tsunamis. It is reasonable to assume that previous earthquake events in the Myanmar-Andaman segment must be preserved in the geological record in the form of seismo-turbidite sequences. Here we present the prospects of conducting deep ocean palaeoseismicity investigations in order to refine the quantification of the recurrence pattern of large subduction-zone earthquakes along the Andaman-Myanmar arc. Our articipation in the Sagar Kanya cruise SK-273 (in June 2010) was to test the efficacy of such a survey. The primary mission of the cruise, along a short length (300 km) of the Sumatra-Andaman subduction front was to collect bathymetric data of the ocean floor trenchward of the Andaman Islands. The agenda of our piggyback survey was to fix potential coring sites that might preserve seismo-turbidite deposits. In this article we present the possibilities and challenges of such an exercise and our first-hand experience of such a preliminary survey. This account will help future researchers with similar scientific objectives who would want to survey the deep ocean archives of this region for evidence of extreme events like major earthquakes.

5 illus, 1 table, 32 ref

010597   Patra R N;Mohanty M (Geological Survey of India, , ) : Exploration for platinum group elements in Odisha. SGAT Bull 2014, 15(1), 57-9.

010596   Patel S (Chaarat Gold Holding Limited, , London, Email: chaarat.com) : Quality assurance and quality control in gold exploration at Chaarat gold, Kyrgyzstan. SGAT Bull 2014, 15(1), 37-45.

Chaarat is one of the largest gold discoveries in the recent times. It is located in the Tien shan orogenic belt of Kyrgyzstan. It is a structurally controlled deposit hosted by the Paleozoic sediments and associated with late Palaeozoic intrusives in fore- and back-arc terrains. The paper discusses the standard operating procedure adopted by Chaarat Gold in its exploration program to eliminate human error, make the results reproducible and meet the standards prescribed by NI-43-101 and JORC for reporting. Being a company listed in AIM, many of these procedures are statutory requirement. Further, the management took a conscious stand from the day one not to compromise on the quality assurance and quality control as it is fundamental to any decision to develop the deposit which involves huge investment. The statutory audit by an agency of good standing carried out by a Competent Person as prescribed by AIM is another measure which makes a stringent operating procedure nonnegotiable.

5 illus, 1 table, 6 ref

010595   Nanjundiah Ravi S;Francis P A;Ved M;Gadgil S (Centre for Atmospheric and Oceanic Sciences, Indian Institute of Science, Bangalore-560 012, Email: sulugadgil@gmail.com) : Predicting the extremes of Indian summer monsoon rainfall with coupled ocean-atmosphere models. Curr Sci 2013, 104(10), 1380-93.

An analysis of the retrospective predictions by seven coupled ocean-atmosphere models from major forecasting centres of Europe and USA, aimed at assessing their ability in predicting the interannual variation of the Indian summer monsoon rainfall (ISMR), particularly the extremes (i.e. droughts and excess rainfall seasons) is presented in this article. On the whole, the skill in prediction of extremes is not bad since most of the models are able to predict the sign of the ISMR anomaly for a majority of the extremes. There is a remarkable coherence between the models in successes and failures of the predictions, with all the models generating loud false alarms for the normal monsoon season of 1997 and the excess monsoon season of 1983. It is well known that the El Ni¤o and Southern Oscillation (ENSO) and the Equatorial Indian Ocean Oscillation (EQUINOO) play an important role in the interannual variation of ISMR and particularly the extremes. The prediction of the phases of these modes and their link with the monsoon has also been assessed. It is found that models are able to simulate ENSO-monsoon link realistically, whereas the EQUINOO-ISMR link is simulated realistically by only one model - the ECMWF model. Furthermore, it is found that in most models this link is opposite to the observed, with the predicted ISMR being negatively (instead of positively) correlated with the rainfall over the western equatorial Indian Ocean and positively (instead of negatively) correlated with the rainfall over the eastern equatorial Indian Ocean. Analysis of the seasons for which the predictions of almost all the models have large errors has suggested the facets of ENSO and EQUINOO and the links with the monsoon that need to be improved for improving monsoon predictions by these models.

9 illus, 2 tables, 43 ref

010594   Mukherjee M M;Gunaseelan T N (IMC, , Kolkata) : Adoption of UNFC-2009 in India- retrospects, prospects and comparison with JORC-style classification. SGAT Bull 2014, 15(1), 83-96.

UNFC 1997-2004 has been accepted by Govt. of India for adoption by all. Now a change-over to UNFC-2009 is under serious consideration for sustainable development. This is an umbrella classification system which is reported to be aligned with the key commodity-specific systems in place worldwide forminerals -International Reporting Template. It addresses the minerals, petroleum and uranium sectors using a single set of definitions and terminology. India had adopted UNFC scheme of classification system of 1997-2004 almost verbatim as reporting standard for mineral resource and reserve but its scope for the classification of Mineral Resource and Mineral Reserve estimates into various categories deserve enlargement and immediate attention. The terms "reserves" and "resources" are not defined in UNFC-2009, because they both have specific, but different, definitions in the solid minerals and petroleum sectors. The three axes namely E, F, and G have been redefined as Socio-economic viability, Project feasibility and Geological Knowledge respectively and terms like Commercial Projects, Potentially Commercial Projects, Non-commercial Projects, Exploration Projects and Additional quantities in place have been proposed instead. JORC-style classification addresses commercial issues more pointedly keeping in mind that companies are not necessarily interested in resources if they have no reasonable prospect for economic exploitation in the near future under expected market conditions. The dichotomy between UNFC and JORC appears complex and difficult to resolve at the moment.

3 illus, 3 tables, 3 ref

010593   Mohanty R C;Patnaik B C (SGAT, , ) : Exploration program for developing new bauxite mines : challenges and oppor tunities. SGAT Bull 2014, 15(1), 109-115.

After discovery of East Coast Bauxite Deposits having resources of about 2 billion tones, prospect of development of aluminum sector in India appeared to be bright. Success of NALCO in utilizing this bauxite for the first time, producing aluminum metal at low cost and getting recognition in international market, projected India as one of the potential global players for future. The expected growth of aluminum sector could not be achieved because of agitations spearheaded by eco-political groups on the pretext of environmental and social impacts of bauxite mining in the locality. As such, Panchpatmali of NALCO is the only established mine, while all the other major bauxite deposits with more than 1.5 billion Tones still remain virgin. While the existing refineries of this sector suffer due to non-availability of bauxite, there is little hope of developing new mines over these deposits. The objective of the paper is to develop some small mines as quick as possible with very low cost and demonstrate the people in the locality that Bauxite mining is eco-friendly. More than 250 small deposits and some in clusters exist in East Coast. Suitable ones can be initially planned for exploration to prove the resources and confirm it by exploratory trial pits. Subsequently, the trial pits can be extended as small quarries to meet the requirement of the existing industries. All attempts have to be adopted in these model mines to convince the local people and others that they should not be biased and allow bauxite mining for their socio-economic development. The proposed programs have to be initiated by Govt. or PSUs. The exploration program is planned to be economically viable with scope of income generation and eco-friendly operation. In long term, it would help in growth of industry which is the objective of all exploration programs.

2 illus, 2 tables

010592   Mitra A K et al (National Centre for Medium Range Weather Forecasting, , A-50, Area, Sector 62, Noida 201 309, Email: ashis.mitra@nic.in) : Prediction of monsoon using a seamless coupled modelling system. Curr Sci 2013, 104(10), 1369-79.

Rainfall for India and South Asian region mainly comes during the summer monsoon period. Realistic model representation of monsoon rainfall variability is a scientific challenge and is of great societal consequences. Due to scale interactions, study of monsoon variability and predictability from hours to a season using a realistic model is of vital importance. Under the Ministry of Earth Sciences, National Monsoon Mission, National Centre for Medium Range Weather Forecasting (NCMRWF) is focussing on the week-2 forecast of monsoon rainfall using a coupled model and its initialization. Improving the skill of models within the timescale of the first two weeks period is vital because of its seamless connection to the monsoon intraseasonal and seasonal variability and prediction. Model development for monsoon rainfall has to be dealt in a holistic way, including the scales from days to a season. NCMRWF on its effort to undertake advanced research in tropical/monsoon simulation/prediction across a range of timescales from hours to a season, has made one incremental step forward by implementing a state-of-the-art coupled model. In this study, we report results from monsoon simulations from the high-resolution global assimilation-forecast set-up in NWP medium range timescale and also from the simulation results from a relatively coarser coupled model. The monsoon lower tropospheric flow and associated rainfall patterns are quite realistic. The existing model biases in flow, rainfall and surface parameters are also discussed. To remain at the fore-front of monsoon prediction, a much higher resolution version of the coupled model and its initialization component will be implemented in the coming years on a more powerful supercomputer. The focus will be to improve simulation of coupled monsoon variability in timescale of hours to a season with an aim to improve forecast skill in week-2 time-period over the Indian region.

11 illus, 59 ref

010591   Khosla V;Jain S C (CMPDI, , RI-VII, Bhubaneswar) : Detailed coal exploration planning & management and strategu & challenges. SGAT Bull 2014, 15(1), 1-12.

2 illus, 5 ref

010590   Guharay A;Chenna Reddy K;Chakrabarty D; Yellaiah G (NO, National Institute for Space Research, Sao Jose dos Campos, 12237-010, Sao Paulo, Brazil, Email: guharay@laser.inpe.br) : Study of meteor characteristics over Gadanki using VHF radar observations. Curr Sci 2013, 104(10), 1425-30.

Meteor characteristics during shower and non-shower periods in 2005-2008 have been studied using narrow beam (HPBW ~3±) VHF radar at Gadanki (13.5±N, 79.2±E). Various interesting echoes are illustrated and probable explanations for their behaviour are also provided. Doppler spectra of the Range Spread Trail Echo indicate a probable plasma convergence and gradient drift instability associated plasma turbulence in some cases.

4 illus, 1 table, 22 ref

010589   Gowthaman R;Sanil Kumar V;Dwarakish G S;Mohan Soumya S;Singh Jai;Ashok Kumar K (Ocean Engineering, CSIR-National Institute of Oceanography, Dona Paula, Goa-403 004, Email: samo;@mop.org) : Waves in Gulf of Mannar and Palk Bay around Dhanushkodi, Tamil Nadu, India. Curr Sci 2013, 104(10), 1431-4.

Surface wave characteristics around Dhanushkodi are studied based on the measured data in the Gulf of Mannar and in the Palk Bay. Wave spectra are mainly double-peaked in the Gulf of Mannar and single-peaked in the Palk Bay. High waves (maximum wave height up to 5.4 m) are observed in the Gulf of Mannar compared to the Palk Bay (maximum wave height is 3.6 m). Wave heights are more in the Gulf of Mannar during the southwest monsoon period and the waves are from south-southwest. In the Palk Bay, high waves are found during the northeast monsoon period. Swells dominate the Gulf of Mannar, except during the southwest monsoon period, whereas wind seas exist in the Palk Bay as distant swells cannot reach the bay due to the protection by Indian peninsula and northern extremity of Sri Lanka. Influence of cyclone Laila is observed during the study period in both the Gulf of Mannar and the Palk Bay.

3 illus, 2 tables, 20 ref

010588   Francis P A;Vinayachandran P N;Shenoi S S C (Indian National Centre for Ocean Information Services, , Hyderabad-500 090, Email: shenoi@incois.gov.in) : The Indian Ocean Forecast System. Curr Sci 2013, 104(10), 1354-68.

In order to meet the ever growing demand for the prediction of oceanographic parametres in the Indian Ocean for a variety of applications, the Indian National Centre for Ocean Information Services (INCOIS) has recently set-up an operational ocean forecast system, viz. the Indian Ocean Forecast System (INDOFOS). This fully automated system, based on a state-of-the-art ocean general circulation model issues six-hourly forecasts of the sea-surface temperature, surface currents and depths of the mixed layer and the thermocline up to five-days of lead time. A brief account of INDOFOS and a statistical validation of the forecasts of these parametres using in situ and remote sensing data are presented in this article. The accuracy of the sea-surface temperature forecasts by the system is high in the Bay of Bengal and the Arabian Sea, whereas it is moderate in the equatorial Indian Ocean. On the other hand, the accuracy of the depth of the thermocline and the isothermal layers and surface current forecasts are higher near the equatorial region, while it is relatively lower in the Bay of Bengal.

18 illus, 5 tables, 47 ref

010587   Faruque B M (Geological Survey of India, , Zahirland, Tinkonia Bagicha, Cuttack-753 001) : Exploration of the seabed for mineral resources in the Indian shelf region: a synoptic view. SGAT Bull 2014, 15(1), 116-25.

Earlier the ocean basins were regarded as huge reservoirs that simply held the oceans and served as a repository of the disintegrated rock material transported from the continents. Evolution of the concept of plate tectonics followed by the researches in marine geology have helped understand the formation and loci of marine minerals that are derived by the following processes: terrigenous mineral resources- eavy minerals; biogenic mineral deposits skeletal remains (carbonate sand and limestone); chemogenic minerals (lime and phosphorite); mineral deposits associated with the hydrothermal processes comprise metalliferous sediments, sulphides, polymetallic manganese nodules and the hydrocarbons trapped in the reservoirs of older sedimentary structures and frozen with moisture as gas hydrate. In the Indian set-up all the above types of minerals have been discovered and their occurrences have been delineated, by the Geological Survey of India. Beach and offshore heavy minerals in the shelf off southern Odisha, north Andhra Pradesh, southern Kerala, western Tamilnadu, parts of Maharashtra coast around Ratnagiri, are some of the mineral deposits. Phosphorite occurrences have been mapped in the shelf and slope region off Gujarat and Tamilnadu. GSI has mapped lime mud in the outer-shelf off Andhra Pradesh and Gujarat. Carbonate sand is seen almost in the entire shelf edge except for sectors off deltaic regions. The paper includes case history of exploration for offshore heavy minerals and geochemical scan for microseepage of hydrocarbons in the Indian exclusive economic zone, carried out by the Geological Survey of India.

010586   Das G C;Patel S (Geological Survey of India, , ) : Exploration for gold at Hutti in India and Chaarat in Kyrcyzst an - a comparative case study. SGAT Bull 2014, 15(1), 67-77.

11 illus, 9 ref

010585   Biswal B C (NO, Metallurgical and Material Engineering, Dy. Manager, Forge shop, HAL, Koraput) : Isothermal forging: A state of art of forging process for manufacturing of aero engine components. SGAT Bull 2014, 15(2), 50-6.

Titanium and titanium alloys are used extensively both as structural materials and engine component materials in aerospace applications because of their high specific strength which results in significant weight reduction. Due to increasing demand for higher performance of titanium alloys in aerospace sector requires new processing technique to be developed to tailor the microstructure. This requirement gives a reason to develop a unique forging method known as isothermal forging. The isothermal forging technology emerged as development efforts in the early 1970s and became a production reality shortly thereafter. Basically this is a forging process where the forging stock and the die temperature maintained at equal/ near equal temperature throughout the forging cycle. Slow deformation within tight temperature ranges minimize flow stress, minimize deformation heating, and allow super plastic behavior of titanium alloys. The process itself claims to produce net/nearnet shape components, leading to optimum utilization of materials, product Uniformity and optimum mechanical properties. In aero engine industries engine inlet fan blades and compressor blades are manufactured to near net shape from many years. However blades in recent advanced aircraft engines i.e Al-31FP, Pratt & Whitney F119-PW-100, RD33 engine are made from difficult to forge alloys with very thin aerofoil with less tolerance for thickness and geometrical deviations. Due to increasing demand for thinner aerofoil, sharper edge radii, close tolerances and high strength to density and modulus to density ratio Isothermal forging of Ti-alloys came in to picture for producing fans and Compressor blades of aero engine.

010584   Adhikaree S (NO, Odisha Mineral Sands Project (OMSP), TSPL Bhubaneswar, Email: sudhakar.adhikaree@trimexgroup.com) : Value addition option for the mineral sand resources of odisha, with particular reference to oxides of titanium like ilmenite. SGAT Bull 2014, 15(2), 1-6.

Hinterland geology, hot and humid tropical climate and favourable coastal geomorphology makes 2100 km of the Indian Coast line, including 105km of Odisha, a potential target for placer mineral sands. The Odishan coastal placers dominantly comprise of Ilmenite (45 Million Tonnes), Garnet (33 Million Tonnes) and Sillimanite (21 Million Tonnes) out of the total heavy mineral resource of 106 Million Tonnes. Ilmenite offers wide scope for value addition to TiO₂ Pigment, which is the market driver for titanium feedstock. The Odishan ilmenite shave lower TiO₂of around 48-50% and require beneficiation/upgradation to intermediate products like Synthetic Rutile (SR) or Titania Slag.For the SR (a chemical process of corrosion/leaching),there are issues of (i) handling logistics for the specific type of coal required in Bechar SR, (ii) technology transfer for Benilite SR, and (iii) environmental impact and cost involved in disposal of the huge chloride contaminated iron oxides/hydroxides generated. For the Ti-Slag (a pyro-metallugical process),though the chemistry of Odishan ilmenite is ideal and both the products of this process (Ti-Slag and Pig Iron) are equally good and saleable, the cost of power in this extremely power intensive route, holds the key. It is suggested that if cost of power can be reasonably handled, the Ilmenite-TiSlag-TiO₂ Pigment value addition chaincan become the success formula for the huge potential of Odishan Ilmenites.

009576   Wadhawan S K;Raju M;Ghosh S;Bodas M S;Ghoshal T B;Jaiswal P (NO, Geological Survey of India, 27 J.L. Nehru Road, Kolkata-700 016, Email: saibal.springdale@gmail.com) : Geoscience considerations in formulation of national landslide disaster management plan. Indian J Geosci 2013, 67(3-4), 203-16.

Nearly 15% of Indian landmass (about 0.49 million km^{2) in mountainous terrains (including permafrost and ice-covered areas) are prone to landslide hazards. Like other natural hazards such as earthquake, flood, landslide-related disasters also cause havoc and often register considerable fatality and complex nature of damage pattern in mountainous terrains in India. Therefore, to minimize its losses, an effective Landslide Disaster Management Plan (LDMP) is needed. According to the National Disaster Management Act (2005), LDMP should give maximum stress on preparedness and mitigation rather than incurring more expenditure and making ad-hoc arrangements for relief and rehabilitation measures. Thus, the onus of effectively managing landslide-related hazards becomes a challenging task because preventing or minimizing losses owing to an inevitable and consequential geomorphic phenomenon like landslides needs proper geoscientific appraisal and studies which should be the integral part of any detailed disaster management plan. To successfully implement the LDMP, the roles of the State Governments and all the stakeholders including Geological Survey of India (GSI) being the nodal agency are crucial which needs to be defined in ft well-coordinated manner. This paper documents in the form of a Standard Operating Procedure (SOP), the roles and responsibilities of the relevant and best geoscientific practices for effectively mitigating and managing this particular hazard which could be the fundamental basis for framing the LDMP for landslide-prone areas in India.}

1 illus, 1 table, 38 ref

009575   Wadhawan S K;Jaiswal P;Ghosh S (NO, Geological Survey of India, 27 J. L. Nehru Road, Kolkata-700 016, Email: pankaj.jaiswal2@gmail.com) : Landslide early warning in India-prospects and constraints. Indian J Geosci 2013, 67(3-4), 229-36.

Forecasting of a natural disaster has gained importance in many disciplines, including landslide studies. The literature on landslide early-warning system illustrates the developments and successful use of the warning in 1980s by United State Geological Survey in the San Francisco Bay area. In the last few decades, several attempts have been made to quantify rainfall thresholds required to trigger one or more landslides. Several studies have also been carried out for site-specific monitoring of individual landslide for issuance of early warning. However, the development of a real-time early-warning system for absolute prediction of landslides, both in space and time, and communication of warning to individuals by local authorities may appear a step too far, especially in large developing countries like India. This paper attempts to highlight the problems associated with developing early-warning system over larger areas, to discuss a number of difficulties related to modelling landslide initiation, including geospatial and temporal aspects, magnitude and slide run-out issues. It is imperative to provide scientific observations, analyses and research-based data that would enable the Nation to become more resilient to natural hazards, including landslides. A number of new initiatives, taken by the Geological Survey of India, the 'Nodal' agency for landslide studies in India, in these regards, particularly in landslide monitoring and development of an early-warning system, are enumerated.

2 illus, 27 ref

009574   Vishnu R;Anil Kumar V;Varikoden H;Krishnan K S;Sreekanth T S;Subi Symon V N;Das S M;Kumar G M (NO, Centre for Earth Science Studies, Thiruvananthapuram-695 031, Email: vishnuplr@gmail.com) : Convective thundercloud development over the western ghats mountain slope in Kerala. Curr Sci 2013, 104(11), 1506-14.

Studies were carried out on the data from Braemore mountain observatory (lat. 8°45'N, long. 77°5'E) using a single-lens ceilometer (LIDAR), an electric field mill and a portable automatic weather station throughout the year 2010. The simultaneous data collected using the above instruments indicate the existence of strong updrafts followed by the formation of thunderclouds, a characteristic of the mountain slopes, during the thunderstorm months. Changes in atmosphere related to condensation and formation of water droplets during updraft events on the mountain slope could be detected from the ceilometer scattering data. Results of the study point to the cause of relatively more thunderstorm activity in that zone. This seems to be due to excessive updraft, which is strongly related to lightning activity in the region.

13 illus, 2 tables, 23 ref

009573   Vinod Kumar;Hosalikar K S;Rajeev V K;Kamble D S;Pareekh N I;Khanum N (NO, , Meteorological Office, Mumbai, Email: vinodmanjusingh@yahoo.co.in) : Killer tornadoes during high tide period. Mausam 2013, 64(2), 379-84.

1 illus, 1 table, 10 ref

009572   Theophilus P K;Chasie M;Sarkar N K (Geological Survey of India, Landslide Hazard Zonation Project, Northeastern Region, Shillong-793 003, Email: niroj4@gmail.com) : Field-based lanslide inventory-constraint from two contrasting geological domains of North East India. Indian J Geosci 2013, 67(3-4), 237-48.

Study highlights the perspective landslide hazard assessment of the two contrasting geological domains of North East India attempted through a detailed field-based landslide inventory work. Landslide inventory data were generated through detailed evaluation of various kinds of slope failures along major communication corridor between Bomdila and Tawang township of Arunachal Himalaya and that of some of the major communication corridors of the plateau region of central Meghalaya. The generated database was analysed and synthesized to understand the landslide susceptibility across these contrasting geological domains of North East India. Detailed characterization of the landslide/cut slope failures was done through study of distribution, types and pattern in the said two domains. The study highlighted both the geological control and large-scale anthropogenic interferences mostly in the form of excavation of natural slope for making and widening of road benches. Understanding of landslide initiation processes in these domains through the present study can be utilized for perspective assessment of landslide susceptibility, hazard, and risk scenario across the North East India. The significance of mass wasting with respect to the landscape evolution in the region is also discussed.

20 illus, 4 ref

009571   Subramanyam K S V;Balaram V;Reddy U V B; Satyanarayanan M;Roy P;Sawant S S (NO, CSIR-National Geophysical Research Institute (CSIR-NGRI), Hyderabad-500 007, Email: konduri2003@yahoo.com) : Problems involved in using improper calibration CRMs in geochemical analyses: a case study on mafic rocks of Boggulakonda pluton, east of Cuddapah basin, India. MAPAN 2013, 28(1), 1-9.

The performance and response of two commonly used certified reference materials (CRMs) for mafic rocks MRG-1 (CANMET, Canada) and JGb-1 (Geological Survey of Japan), both gabbroic in composition, are evaluated for a set of mafic plutonic rocks (gabbros) from Boggulakonda (BK) occurring to the east of Proterozoic Cuddapah Basin, South India. In this study, quadrupole-inductively coupled plasma mass spectrometry was used to generate trace and rare earth element (REE) data using MRG-1 and JGb-1 as calibration standards separately for a comparative study. It is found that the two CRMs show highly variable major, minor and trace element compositions except ΣREE. When used for BK gabbros, JGb-1 has yielded better results than MRG-1 with respect to trace elements (HFS elements Nb and Ta in specific), whereas a good agreement was observed between both CRMs for REE concentrations when compared with certified data. The Nb-Ta element distribution patterns for BK gabbros in the spidergrams plotted using JGb-1 as CRM show relatively prominent and pronounced negatively spiking anomalies with reference to Th, whereas using MRG-1 as calibration CRM yielded unresolved and unclear Nb-Ta anomalies in the present study. The geochemistry (major, minor and trace) of MRG-1 is different when compared to that of JGb-1. Probably this is reason for the disparity in the results obtained by inductively coupled plasma mass spectrometry on mafic plutonic rocks. The study conducted on the BK gabbros, reveals better and reliable results using JGb-1 as CRM. This study also reveals the importance of using proper CRM for calibration having closely matching trace and REE concentrations in addition to major and minor elements, for obtaining reliable data in geological samples.

9 illus, 4 tables, 32 ref

009570   Srivatava H N;Singh R K;Singh D;Prakash R; Shukla A K (NO, , 128, Pocket, A, Sarita Vihar New Delhi-110 076, Email: dal.singh538@gmail.com) : Comparative study of before and after effects of Bhuj (2001) and Muzafarbad (2005) earthquakes in [hindi]. Mausam 2013, 64(2), 323-44.

Bhuj 2001 and Muzaffarabad 2005 earthquakes of same moment magnitude of Mw:7.6 occurred in different tectonic regions, i.e. intraplate and interplate regions of Indo-Eurasian plates respectively. Keeping this in view, their comparative study has been attempted in this paper. A detailed catalogue of earthquakes has been prepared to study seismicity of Kutchh region by including historical and paleoseismic data. Discussion on seismicity of Muzaffarabad earthquake is based on IMD catalogue of earthquakes. Difference has been found between Bhuj 2001) and Muzaffarabad (2005) earthquakes based on their foreshocks, magnitudes of aftershocks and their decay, b-value and their spectra. Though no relation between magnitudes of aftershocks and stress drop could be found but mostly the corner frequency and magnitude are inversely related. Difference in both these large earthquakes (M ≥ 7.6) occurring in different tectonic plate set up is clearly evident from their stress drop. Seismic gap is noticed prior to main event of Muzaffarabad earthquake; which is similar to other Himalayan earthquakes of that region like Uttarkashi (1991) and Chamoli (1999). From the point of view of earthquake prediction, the results based on satellite thermal anomalies, ionosphere, electromagnetic and sodar observations reported for these earthquakes are considered to be of limited value due to the larger influence of atmospheric parameters Though approximate displacement measured through GPS is useful for calculating the plate motion but their results to derive large vertical displacement is questionable in case of Bhuj earthquake due to use of standard radio atmosphere. The errors in such results can be reduced by adopting radio atmosphere for the Indian region. Through a review of methodologies to predict the strong ground motion in the near field, it is evident that further research is called for.

7 illus, 6 tables, 53 ref

009569   Srivastava T P;Devrani A (Met Faculty, Air Force Administrative College, Red Fields, Coimbatore, Email: tarendrasrivastava@gmail.com) : Track, intensity and few dynamical aspects of 'AILA' as simulated by operational NWP model of the IAF. Mausam 2013, 64(1), 59-76.

Attempt has been made in this study to analyse the efficacy of operational NWP Model of the 1AF in predicting the track, intensity, landfall and few dynamical aspects of 'AILA' a Severe Cyclonic Storm that formed over the Bay of Bengal and affected West Bengal during May 2009. Model runs were done with and without employment of cumulus parameterisation scheme in the finer domain of 6 km. The forecasts of D-l were relatively better and more realistic in comparison to the one generated on D-2, in both sets of experiment, respectively. Patterns with cumulus parameterisation produced delayed convection but with finer details in comparison to the patterns generated without it. Maximum radar reflectivity without using cumulus parameterisation scheme in the finer domain of 6 km, compared well with the actual reflectivity of Kolkata DWR both in time and space.

52 illus, 2 tables, 7 ref

009568   SivaKumar K N;Sudarsana Raju G;Raghu Babu K (Geology and Geoinformatics Dep, Yogi Vemana Univ, Kadapa-516 003) : Geohydrological studies in and around Talupula-Nambulapulakunta, Anantapur district, Andhra Pradehs, using remote sensing techniques. Indian J envir Prot 2013, 33(9), 737-42.

Remote sensing techniques using satellite imagery have proved to be an indispensable tool in morphmetric analysis and ground water studies. Remote sensing techniques with an emphasis on lithological and structural identification plays a great role in ground water prospecting and applied on hard rock area of Talupula and Nambupulakuntapalli of Anantapur district. Geohydrological studies have been carried by using satellite data for the study area through visual interpretation of IRS P6 LISS111 imagery 57J/08 of on a scale 1:50000. The area has been visually interpreted to delineate various geology, geo-morphology and geohydrologic units for the development of ground water potential zones. The geohydrological map delineated depicts 4 zones in which high potential zones carries a better ground water resource, when compare to the medium and low potential zones. Where as non potential zones are of barrier lands with hard rock terrain.

5 illus, 13 ref

009567   Singh B P;Singh N;Singh S P (Centre of Advanced Study in Geology, Banaras Hindu Univ, Varanasi-221 005, Email: drbpsingh1960@gmail.com) : Modern salt (halite) deposits of the sambhar lake, Rajasthan and their formative conditions. Curr Sci 2013, 104(11), 1482-4.

^ssc2 illus, 8 ref

009566   Sharma V K;Rawat P V S (NO, Geological Survey of India, State Unit: Uttarakhand, Northern India, Dehradun-248 001, Email: vksharma_gsi@yahoo.co.in) : Post-disaster slope stability evaluation of catastrophic events in Uttarakhand. Indian J Geosci 2013, 67(3-4), 337-46.

The 30,000 km^{2 area in Uttarakhand has witnessed numerous landslides, subsidence and bank erosion after intense rainfall and cloudburst of 16-17 June 2013. The disaster rendered 845 people missing from the Uttarakhand and about 3000 people from other parts of the country and confirmed death of 159, besides colossal damage to houses, livestock, loss of agricultural and forest land. The Kedarnath Township, that houses the holy temple, was the worst affected area where heavy rains, cloudbursts and Glacial Lake Outburst (GLOF) phenomenon changed the course of Mandakini River. The unprecedented flood left lakhs of people stranded. In the present paper post-disaster evaluation of slope stability issues of the catastrophic event has been attempted in five worst-affected districts viz. Rudraprayag, Uttarkashi, Chamoli, Pithoragarh and Bageshwar. The scale of damage caused by the slope failures due to flash floods attained alarming dimensions due to highly vulnerable slopes, glacio-fluvial terraces, morain dump material, etc. Geo-parametric data of 419 landslide locations in different districts have been collected and immediate, short-term mitigation measures have been suggested, besides identifying critical location for detailed studies. In addition, 112 villages were also studied to suggest various remedial measures for reconstruction and rehabilitation to safer zones in proximal environment.}

13 illus, 10 ref

009565   Sharma R S (NO, , 70/36, Pratap Nagar, Sanganer (RHB), Jaipur-302 033, Email: sharma.r.sw@gmail.com) : DST-sponsored field workshop. Curr Sci 2013, 104(11), 1470-70.

009564   Sen K;Tripathi K;Dubey A K (NO, Wadia Institute of Himalayan Geology, Dehradun-248 001) : Is the north Indian continental margin a palaeo-proterozoic magmatic arc? insights from magnetomineralogy and geochemistry of the wangtu gneissic complex, Himachal lesser himalaya. Curr Sci 2013, 104(11), 1527-33.

Magnetomineralogical, petrographic and whole-rock geochemical studies on the Palaeo-proterozoic Wangtu Gneissic Complex (WGC) of the Himachal Lesser Himalaya have been carried out to understand the tectonic setting of the northern Indian continental margin during the Palaeo-proterozoic. Petrography and mag-netomineralogy suggest that, although the WGC is dominantly composed of S-type/two-mica granitoids having low magnetic susceptibility (<60>500x10^{-6 SI units), part of the complex consists of hornblende-magnetite and biotite-magnetite-bearing I-type granitoids having susceptibility greater than 500 x 10-6 SI units. Comparison of magnetic susceptibility with major element concentration reveals that the high susceptibility (<62>500 x 10-6 SI units) granites are low in silica content and enriched in ferro-magnesian content. Tectonic discrimination based on trace element concentration shows that both I- and S-type granitoids of the WGC contain concentration of Y, Nb and Rb consistent with a collisional/volcanic arc set up. It is concluded that the North Indian continental margin had an active colli-sional set up during the Palaeo-proterozoic.}

5 illus, 2 tables, 31 ref

009563   Sen Jaiswal R;Neela V S;Sonia R F;Rasheed M; Zaveri L;Sowmya V (NO, Centre for Study on Rainfall and Radio wave Propagation Sona College o, Salem-636 005, Email: crrp.official@yahoo.com) : Identification of key parameters producing rainfall. Mausam 2013, 64(2), 281-96.

In search of the key parameters causing rainfall, the authors have explored Tropical Rainfall Measuring Mission (TRMM) satellite data base. By realizing the fact that evaporation of water, condensation of vapour and transport of heat energy by a rising air parcel are all about formation of cloud and rain, the authors have started their quest considering cloud liquid water (CLW), precipitation water (PW) and latent heat (LH) at different altitudes of the atmosphere as major contributors to rainfall mechanism. These data have been fitted to multiple regressions. It is found that significant correlations exist between rainfall and these parameters. The functional relationships so established are able to estimate surface rainfall at any instant, provided columnar CLW, PW and LH values are available. Inclusion of all the three parameters in multiple regression leads to better predictability of rainfall, instead of one or two. Significant correlations exist between CLW, LH and PW.

33 ills, 11 tables, 5 ref

009562   Sawaisarje G K;Shirke C Y;Mohite S (NO, , Meteorological Office, Pune-411 005, Email: gksawaisarje@gmail.com ) : Normalized anomaly patterns of meteorological elements: a case study of northeast monsoon 2002 and 2004. Mausam 2013, 64(2), 297-308.

It is often helpful to express the meteorological data in terms of normalized anomalies as they make it easier to discern normal versus unusual values. Also it removes influence of location and spread from data and facilitates the comparison of observations at two different locations. Thus, Normalized Anomaly (NA) patterns i.e., spatial distribution of anomalies at specified time make a powerful tool in hand of forecasters to analyze extreme events. The present study explores the utilization of NA patterns for the purpose of analyzing extreme events by focusing on the inter-seasonal peculiar behavior of Northeast monsoon 2002. A detailed discussion is given and reasons are explored for droughts like situations during Northeast monsoon 2002. It was also noticed that the persistence of 200 hPa upper level ridge or positive geopotential height anomaly, negative mean sea level pressure anomaly over Siberian High during November, strength of 200 hPa wind anomaly can be one of the reasons for drought-like situation observed in the inter-seasonal behavior pattern of Northeast monsoon 2002. NA patterns of low cloud amount, dry bulb temperature and relative humidity captured drought-like situations during Northeast monsoon 2002 while 'NA of average wind speed captured the scenario of dissipating cyclones in the Bay of Bengal itself and not reaching to Peninsular India. The NA patterns of low cloud amount, relative humidity, dry bulb temperature and average wind speed for Northeast Monsoon 2004 confirm the observations of drought like situations seen in NA patterns for these meteorological parameters in case of Northeast monsoon 2002.

36 illus, 8 ref

009561   Sathiyamoorthy V;Paul Shukla B;Sikhakolli R; Chaurasia S;Baby Simon;Gohil B S;Pal P K (Atmospheric and Oceanic Sciences Group, Earth, Ocean, Atmosphere, Planetary Sciences and Application Area, Spa, Ahmedabad-380 015, Email: bsgohil@sac.isro.gov.in) : Top of atmosphere flux from the Megha-Tropiques ScaRaB. Curr Sci 2013, 104(12), 1656-61.

One of the important payloads on-board the joint Indo-French Megha-Tropiques satellite is the Scanner for Radiation Budget (ScaRaB). It is dedicated for monitoring the Earth Radiation Budget (ERB) parameters at Top of Atmosphere (TOA). In this article, details of the algorithm used for computing two important ERB components, namely TOA reflected shortwave and emitted longwave fluxes from ScaRaB radiance measurements are presented along with preliminary cross-satellite validation results. The ScaRaB flux computation algorithm is similar to the one used in the ERB Experiment. The maximum likelihood estimation algorithm is used for identification of different Earth scenes and cloud types. First, the raw radiances are corrected for spectral filtering effects followed by implementation of scene-type dependent angular correction to deduce shortwave and longwave fluxes. The instantaneous TOA flux data derived from ScaRaB radiance measurements are compared with similar data available from Clouds and Earth's Radiant Energy System (CERES) onboard Aqua and Terra satellites. Preliminary comparison confined to two months period (September-October 2012) using the two satellites suggests that the ScaRaB data are in good agreement with the CERES data. The bias-corrected root mean square difference in ScaRaB longwave flux is 4.7 and 5.3 Wm^{-2 with respect to CERES on-board Aqua and Terra satellites respectively. For ScaRaB shortwave flux, it is 25.9 Wm-2 and 25.5 Wm-2 with respect to CERES onboard Aqua and Terra satellites respectively. A detailed comparison of ScaRaB TOA flux data with more than one-year of CERES data is already initiated. Results from the preliminary comparison exercise suggest that the ScaRaB data can be used with confidence for ERB studies.}

3 illus, 13 ref

009560   Sarkar N K;Chasie M;Theophilus P K;Balaji R; Imtikumzuk (Geological Survey of India, Landslide Hazard Zonation Project, Northeastern Region, Shillong-793 003, Email: niroj4@gmail.com) : Debris flow characterizations, causes and consequences-a study from Kohima district, Nagaland, India. Indian J Geosci 2013, 67(3-4), 303-12.

Three prominent recent debris flows along the slope at Kohima Municipal Council (KMC) old dumping site, Phesama and Meriema, adjoining to National Highway Corridor, in the Kohima District of Nagaland were identified and documented. The debris flow along with other kinds of slope failures in the said locations are responsible for blockade of road traffic, destruction of agricultural and forest land, partial blockade of river course and therefore, responsible for consequent economic losses, social concerns and environmental degradations. The identified debris flows were characterized in respect of the length, area, volume, length/height ratio, slope, material of the flow path, zone of initiation and accumulation. Coarse, variably compacted slided debris material with finer matrix released from moderate to steep slope during recent and earlier episodes of mass wasting are found to have transported downslope as run out for significant distance (maximum up to 1545 m). The large volume (155,000 m^{3) of debris flow from KMC old dumping site is also found to have partially blocked a prominent river and caused further slope failure in the opposite bank due to erosion. The causal factors and mechanism of the debris flow generation are interpreted in terms mobilization, nature of flow and deposition. Mobilization for generation of debris at the hill slope has been explained in terms of poor rockmass [low Rock Quality Designate (RQD)] of variably weathered, jointed; inter bedded shale-dominated sequence of Tertiary Disang Group, action of surface and subsurface water flow, intermittent slope failures which resulted in generation of thin to thick (1-5 m) heterogeneous overburden on the slope consisting of a mixture of in-situ soil, weathered rock fragments and locally released rock debris, the matrix of which is largely dominated by clay to silt size fractions. The finer matrix of mixed overburden due to high porosity and low permeability is saturated within a very short period and during high anomalous rainfall, the same material is supersaturated with meteoric water and behaves more like a fluid with high mobility. The supersaturated debris-mixed fluid descended downslope at a considerable speed due to its momentum. The said interpretation from the studied area supports the contention that though debris flow can originate by various means, initiation from slope failures predominates, which begins with incipient slope movement and ends with deposition. The physical understanding and properties of debris flow studied elsewhere indicates that highly viscous and nearly incompressible pore fluid composed of water with suspended silt and clay, can strongly mediate inter granular friction and collisions. Grain friction, grain collisions and viscous fluid flow may transfer significant momentum simultaneously. Both the vibrational kinetic energy of solid grains and the pressure of the intervening pore fluid facilitate motion of grains past one another, thereby initiating and enhancing debris flow mobility. The debris flow identified in the area may be similarly modelled for understanding debris flow susceptibility of the entire Kohima Master Plan area and consequences of the same in respect to the economic loss, social concerns and environmental degradation.}

15 illus, 15 ref

009559   Samui R P;Kamble M V;Sabale J P (NO, , India Meteorological Dep, Pune-411 005, Email: rsamaui@yahoo.com) : Northeast monsoon rainfall and agricultural production in Tamilnadu and Andhra Pradesh I-rainfall variability and its significance in agricultural production. Mausam 2013, 64(2), 309-16.

Monsoon which directly impacts agriculture is an important component of Indian economy because it influences about a quarter of the GDP and livelihood of 60% of the population who depend on agriculture for their livelihood. India receives rainfall mainly during southwest monsoon season. A considerable rainfall also occurs in India during the post monsoon period called as northeast monsoon during October to December, particularly over eastern and southern states and this is of great significance in agriculture and allied sectors in these regions. Increasing trend of rainfall is noticed from south to north in eastern coastal districts of Tamilnadu. On the contrary, it is higher in coastal southeast districts with decreasing trend in northeast parts of Andhra Pradesh. NE monsoon shows greater impact on agricultural production due to its higher quantum of rainfall compared to that of southwest monsoon rain in Tamilnadu than that in Andhra Pradesh. Studies on impact of rainfall on agricultural production revealed positive impact of NE monsoon on rice and maize production in AP. Maize yield is found to exhibit a consistent positive trend. Loss in production due to heavy to very heavy rain and flooding associated with cyclone or depression was more prominent along the coastal districts of Tamilnadu than that in the coastal districts of Andhra Pradesh during northeast monsoon season. Proper understanding of the variability and developing diversified strategies for agricultural operations alongwith the seasonal prediction of northeast monsoon rainfall would have considerable application value for decision making in agriculture and water resource sectors of these regions.

19 illus, 1 table, 1 ref

009558   Saleem M;Ansari M A;Jyotsana;Saxena A K (NO, LF, HF Impedance and DC Standards, CSIR-National Physical Laboratory, Dr. K S Krishnan Marg, New Delhi-110 012, Email: saleem@nplindia.org) : Study of standard mica capacitors with respect to time and temperature. MAPAN 2013, 28(1), 25-9.

Standard mica capacitors manufactured by General Radio are widely used by National Metrology Institutes (NMIs) and other calibration laboratories. The temperature coefficient and stability of standard mica capacitors play significant role in precision measurement. This paper reports the study of standard mica capacitor (General Radio make) with respect to time and temperature. This study is useful for calibration laboratories while reporting measurement results in Proficiency Testing, Inter Laboratory Comparison programmes and calibration reports.

8 illus, 3 tables, 9 ref

009557   Rao T N;Sunilkumar K;Jayaraman A (NO, National Atmospheric Research Laboratory, Gadanki-517 112, Email: tnrao@narl.gov.in) : Validation of humidity profiles obtained from SAPHIR, on-board Megha-Tropiques. Curr Sci 2013, 104(12), 1635-42.

Megha-Tropiques, an Indo French mission, with four on-board payloads was launched in October 2011 to improve our understanding on hydrological cycle and radiation budget. The SAPHIR (Sondeur Atmospherique du Profil d'Humidite Intertropicale par Radiometrie), a sounder for profiling humidity, is a key payload and expected to play a major role in fulfilling the mission objectives. The present article focuses on the evaluation of SAPHIR-derived humidity profiles against a variety of reference datasets, like measurements from GPS radiosondes and ground-based microwave radiometer, reanalysis datasets and satellite retrievals. The data collected during July-November 2012 were employed to validate humidity profiles. A variety of colocations (matching the sampling volumes of radiosonde and SAPHIR) were employed for the validation against radiosondes, launched from Gadanki. The bias (SAPHIR-derived RH - reference RH) and the rms error are found to be small for near-nadir measurements than those far away from the nadir. Further, the bias shows a clear height dependence with positive (negative) bias dominating in the lowest (uppermost) layers. The RH bias and rms errors are small (within 15%) in the middle layers, altitudes at which the sensitivity of SAPHIR channels is high. The comparisons with ECMWF interim reanalysis (ERA) and advanced infrared sounder (AIRS) data, used to extend the evaluation of SAPHIR data to the entire tropics, reveal strikingly similar spatial and vertical structure in RH bias. The vertical structure of RH bias is somewhat similar to that obtained with the radiosonde. Large biases are seen in regions adjacent to South America and Africa in the latitude band of 20°-30°S and large negative bias is seen along the Intertropical Convergence Zone. Possible reasons for such large biases in those regions are discussed.

5 illus, 1 table, 16 ref

009556   Raghavan S (NO, , G1, Prathyeka Apts., 12, 1st Trust Link St., Mandaiveli, Chennai-600 028, Email: raglaksh@gmail.com) : Observational aspects including weather radar for tropical cyclone monitoring. Mausam 2013, 64(1), 89-96.

In the context of the Forecast Demonstration Project (FDP) of the India Meteorological Department (IMD), a review is made of the various observational facilities and techniques which can be deployed, for the detection tracking and understanding of tropical cyclones. The real test of the efforts in terms of technology is the performance of our forecasts in an operational context. The paper discusses the steps needed in this regard.

10 illus, 27 ref

009555   Peshin S;Singh S (NO, , India Meteorological Dep, New Delhi-110 003, Email: sk.peshin@imdmail.gov.in) : WMO/GAW inter-comparison of dobson ozone spectrophotometer in tsukuba, Japan-2006 and inter-comparison of national standard 112 with delhi dobson 36. Mausam 2013, 64(2), 317-22.

WMO/GAW campaign for inter-comparison of Dobson Ozone Spectrophotometer was held from 6 to 24 March 2006 at the Aerological Observatory, Tsukuba, Japan. During the inter-comparison campaign, the Indian standard Dobson Ozone Spectrophotometer no. 112 was compared with the regional standard Dobson Ozone Spectrophotometer no. 116. The comparisons confirmed that the Indian standard Dobson Ozone Spectrophotometer no. 112 was in good state of calibration and the data derived from the instrument was reliable. The results of 112 with 36 are also in good agreement with each other.

5 illus, 10 ref

009554   Pattanaik D R;Mohapatra M;Mukhopadhyay B; Tyagi A (NO, , India Meteorological Dep, New Delhi-110 003, Email: pattanaik_dr@yahoo.co.in) : Preliminary study about the prospects of extended range forecast of tropical cyclogenesis over the North Indian Ocean during 2010 post-monsoon season. Mausam 2013, 64(1), 171-88.

There were two cyclonic storms formed during the post monsoon season of 2010 viz., "Giri" a very severe cyclonic storm (VSCS) formed on 19th October and crossed the Myanmar coast on 22nd and the second system "Jal" a severe cyclonic storm (SCS) formed on 2nd November and crossed north Tamil Nadu-south Andhra Pradesh coasts, close to north of Chennai on 7th November, which caused lot of damage in Tamil Nadu and south Andhra Pradesh coast associated with not only strong wind but also due to associated heavy rainfall. The real time extended range forecasts in terms of weekly mean of dynamical variables are prepared for two weeks based on the coupled model outputs from ECMWF, NECP and the 2 models average (2MAVE) of both. The operational forecast for days 5-11 of weekly mean wind and relative vorticity based on 14th October, 2010 initial condition indicates cyclonic circulation at low level over the central Bay of Bengal during the period from 18-24 October associated with the very severe cyclone "Giri". The genesis of the cyclone "Jal" was very much captured in the 2MAVE forecast valid for 12-18 days forecast based on the initial condition of 21st October, 2010. The 2MAVE forecast valid for 1 -7 November based on 28 October and 21 October initial conditions (with forecast period of days 5-11 and days 12-18 respectively) also clearly indicated large positive rainfall anomalies over Tamil Nadu coast and adjoining coastal Andhra Pradesh region like that of observed rainfall anomalies. This preliminary study further indicates that the model forecasts anomaly of weekly cyclonic vorticity maximum of about 2.5x10^{-5 sec-1 combined with a low level convergence anomaly of about -0.8 to -1.0 x 10-5 sec-1 may lead to formation of a tropical cyclone. However, more number of cases required to be analysed for the proper identification of the threshold values for intensification of the system into a cyclone.}

58 illus, 2 tables, 25 ref

009553   Pal S R;Raha D;Pandey P N (Zoology Dep, S.P. College, Jamshedpur, Email: satyaranjan_pal@yahoo.com) : Aspects of global water resource availability, use and its conservation. Proc Zool Soc India 2014, 13(2), 79-84.

Water is a vital substance in all parts of environment. The Indian Ocean contains 97%o of water of which 77x10^{6KM2 of the water is completely unfit for human consumption and industrial and domestic uses because of its high salt contents. The survey of literature reveals that is locked as icecap and0.3%ois available for human consumption. The demand of water increasing approximately 2.4% per year due to high rate of population growth. The developed countries like America require water 600-1200 liters/day/persons and developing countries like India and Pakistan consume 92-120 liters/day/persons as per their living standard. The increasing human population impact of critical availability/scarcity of water by discharge 60% domestic sewage created water pollution. The study envisaged that clean and pure water is not available to 2 people for drinking purposes out of 10 people in the world. The study further reveals that approximately 22/ac peoples are dying every year due to water born diseases like cholera, hepatitis, typhoid, constipation etc. This effect was observed due to mismanagement of water (17-40%) in metro and cosmopolitan cities like Mumbai, Delhi, Kolkata, etc. The study suggests conserving natural resources of water through public awareness in rural and urban area and by the rain water harvesting. The study also establishes some sort of balance between the population growth and urbanization of natural resources.}

2 tables, 8 ref

009552   Nair S;Hosalikar K S (NO, Regional Meteorological Centre, Colaba, Mumbai, Email: nairsusha@gmail.com) : Trends in surface temperature variability over Mumbai. Mausam 2013, 64(2), 251-64.

Observational evidence points to a warming trend in surface temperatures over the globe. This paper focuses on the trends in Maximum and Minimum temperatures over Mumbai. The temperature trends were investigated at different temporal scales from decadal to daily. The seasonal series were also investigated for trends in frequency of occurrences of extreme events. In general an increasing trend is observed over Mumbai, with the increase in Maximum temperatures more than the Minimum temperatures and statistically significant at 95% confidence level. A seasonal distinction is evident with the warming more in the Winter and Post Monsoon seasons as compared to the Pre Monsoon and Monsoon seasons at both the inter-annual and intra-seasonal scales of investigation. The seasonal distinction Was also evident in the extreme temperature analysis. The frequency of occurrences in the hot days and hot nights were more pronounced in the Pre Monsoon and Monsoon seasons as compared to the Winter and Post Monsoon seasons. Symmetric warming trend was observed for both the daytime and nighttime temperatures at both the stations in all the seasons though the variations at Santacruz are statistically insignificant in the Post-Monsoon season.

13 illus, 2 tables, 12 ref

009551   Mohapatra M;Sikka D R;Bandyopadhyay B K;Tyagi A (India Meteorological Dep, Mausam Bhavan, Lodi Road, New Delhi-110 003, Email: mohapatraimd@gmail.com) : Outcomes and challenges of forecast demonstration project (FDP) on landfalling cyclones over the Bay of Bengal. Mausam 2013, 64(1), 1-12.

Programme has been evolved for improvement in prediction of track and intensity of tropical cyclones over the Bay of Bengal resulting in the Forecast Demonstration Project (FDP) FDP programme is aimed to demonstrate the ability of various Numerical Weather Prediction (NWP) models to assess the genesis, intensification and movement of cyclones over the north Indian ocean with enhanced observations over the data sparse region and to incorporate modification into the models which could be specific to the Bay of Bengal based on the in-situ measurements. FDP Programme is scheduled in three phases, viz., (i) Pre-pilot phase (15 Oct - 30 Nov 2008, 2009, (ii) Pilot phase (15 Oct - 30 Nov, 2010-2012) and (iii) Final phase (15 Oct - 30 Nov, 2013-14). India is planning to take up aircraft probing of cyclones over the Bay of Bengal during 15 Oct - 30 Nov, 2013-14 with hired aircraft and dropsonde experiments. To accomplish the above objective, the initiative was carried out with priorities on (i) observational upgradation, (ii) modernisation of cyclone analysis and prediction system, (Hi) cyclone analysis and forecasting procedure, (iv) warning products generation, presentation & dissemination, (v) confidence building measures and capacity building. Various strategies were adopted for improvement of observation, analysis and prediction of cyclone. Several national institutions participated for joint observational, communication & NWP activities during the pre-pilot and pilot phases of FDP campaign during 2008-11. The comparsion of observational systems before and after FDP indicates a significant improvement in terms of Radar, Automatic Weather Station (AWS), high wind speed recorders over the region. It has resulted in reduction in monitoring and forecasting errors. The performance of NWP models have increased along with the introduction of NWP platforms like IMD GFS, WRF, HWRF and ensemble prediction system (EPS). Salient features of achievements along with the problems and prospects of this project are presented and discussed in this paper. With repeated attempts, the aircraft probing of cyclones could not be possible till now. It is a major challenge for the future campaign during 2013-14.

4 illus, 8 tables, 15 ref

009550   Mohanty U C;Osuri K K;Pattanayak S (NO, Indian Institute of Technology, Delhi, Hauz Khas, New Delhi-110 016, Email: ucmohanty@gmail.com) : High resolution mesoscale modeling systems for simulation of tropical cyclones over the Bay of Bengal. Mausam 2013, 64(1), 117-34.

Landfalling tropical cyclone (TC) is one of the natural disasters producing extremely strong winds, torrential rains, floods influencing many kilometers from the point of landfall and storm surges that overwhelm miles of shores resulting loss of lives, and damages to properties. This disaster is higher in the regions covering Bay of Bengal (BoB). Therefore, the India Meteorological Department (IMD) initiated a field project, "Forecast Demonstration Project (FDP) of landfalling cyclones" over the BoB to acquire detailed understanding of genesis, intensity, and structure evolution of TCs so as for better TC forecasting. A comprehensive performance of state-of-the-art mesoscale modeling systems such as Advanced Research Weather Research and Forecasting (ARW), non-hydrostatic mesoscale model of WRF (NMM) and Hurricane Weather Research and Forecasting (HWRF) etc for the simulation of landfalling TCs during pilot phase of FDP (2008-2011) is presented. The study is not meant for the inter-comparison of different modeling systems. In the present study, six TCs namely Rashmi (2008), KhaiMuk (2008), Nisha (2008), Giri (2010), Jal (2010) and Thane (2011) are considered. Though different aspects of the TC such as track, intensity, structure and rainfall are studied in detail, this paper is mainly emphasized on the track and intensity prediction and associated errors. Results indicates that the high resolution mesoscale modeling systems provide better guidance for TC forecast up to 72 hours. However, the track and intensity error is relatively more when these models are initialized with coarser resolution global analyses and forecast fields. This error can be significantly reduced with the assimilation of additional regional observations into model initial conditions. The track forecast errors are calculated with respect to IMD best track observations. In case of ARW system, the forecast errors are 138, 135 and 182 km from no-assimilation experiment. The assimilation of all available observations during FDP period into model initial condition decreases the errors 72, 99 and 126 km at 24, 48 and 72 hour, respectively with an improvement of about 47%. In case of NMM model, the mean (based on 30 sub-cases) track errors are improved by about 32%, 22%, 23%, 28%, 24% and 16% at 00, 24, 48, 72, 96 and 120 hrs, respectively with data assimilation experiments compared to no-assimilation experiment. The HWRF model improved the initial position and structure significantly because of its improved vortex-relocation and initialization procedures and hence captures the rapid intensification of the TC Giri in the subsequent forecast hour.

55 illus, 3 tables, 38 ref

009549   Mishra A K;Maruthi K V;Pradhan U K;Panduranga R (Geological Survey of India, Geochronology and Isotope Geology Division, 15 A & B Kyd Street, Kolkata-700 016, Email: akshaymishra@yahoo.com) : Stabilization of unstable slopes - a case study in Cabo hill near Rajbhavan, Panjim, Goa. Indian J Geosci 2013, 67(3-4), 313-28.

The stabilization of a failing slope needs careful and detailed investigation so as to arrive at effective remedial measures. The part of Cabo Hill, adjacent of Rajbhavan, a 1540-AD historical monument, was affected by instability, which is manifested by development of tensional and longitudinal cracks, movement in the pavements and tilting of trees. Detailed geotechnical investigations including surface geological mapping, evaluating cross sections, drilling, Standard Penetration Tests (SPT) and characterizing crack geometry were carried out to decipher the affected slope boundary, the slope geometry, failure depth, depth to critical failure plane using shear parameters of slope-forming material (C and φ). Six bore holes were drilled and samples were collected from the bore holes representing different soil units along depth. The grain size, specific gravity, bulk density, natural moisture content, porosity, compressive strength, cohesion (C) and angle of internal friction (φ) of the samples were determined. Since the spatial disposition of the critical slip circle happens to be an important decisive factor in suggesting various stabilization methods, an attempt was also made to compute the factor of safety ('F') to the existing unstable slope. From the observed surface and subsurface geological conditions of the unstable slopes adjacent to Rajbhavan, the in-situ characteristics of the subsoil, their physico-mechanical properties relevant to the stability analysis of the slope, the position of the critical slip circle and the computed safety factor contours were determined. These analytical techniques facilitated recommendations of various corrective and control measures to stabilize the slopes viz. pre-stressed cable anchors, inclined bore piles with beam caps, rock bolting/shotcreting, sealing of ground cracks in the upper part of the slope; easing of slope and surface drainages, vertical bore piles with beam caps, vertical sand piles, turfing/terrace gardening in the middle part of the slope; construction of retaining wall and effective shore protection in the lower part of the slope.

6 tables, 8 ref