013691   Upadhyay V K;Upadhyay S P (Gandhi Mahavidyalaya, , Mirdha, Beruarbari, Ballia, Uttar Pradesh) : Statistical analysis of rainfall distribution and trend of rainfall anomalies districtwise during monsoon period over eastern Uttar Pradesh. Crop Res 2008, 36(1-3), 375-9.

Statistical analysis of rainfall distribution in different districts of Eastern U. P. during monsoon period for 48 years (1953-2000) has been made in this paper. The statistical parameters such as moments, coefficient of skewness and kurtosis have been computed to understand the nature of rainfall distribution in each district. The rainfall anomalies during monsoon period (June-September) have also been examined for each district by fitting regression lines through 'Least Square Method' and results for rainfall trends for each district of Eastern U. P. have been presented in this paper.

5 tables, 9 ref

013690   Sasmal S K;Choudhury A (NO, S.D. Marine Biological Research Institute, Bamankhali, Sagar Island, 24 Pgs (S), West Bengal) : Ichthyoplankton assemblages in the Hooghly estuary, Sagar island, Sundarbans, West Bengal, India. Envir Ecol 2009, 27(3), 1090-4.

Ichthyoplankton survey (in five sampling sectors in three stations) was conducted in Hooghly estuary in 2008 to assess abundance, distribution and seasonal occurrence of juveniles of estuarine fishes. The ichthyoplankton samples collected with plankton nets (mesh size 550-650 pm). The taxonomic composition of ichthyoplankton comprised 65 taxa with 27 genera, 38 species under 20 families. Maximum abundance of fish juvenile occurred during March to June (pre-monsoon season), minimum abundance during September to February (post-monsoon season). Species diversity was maximum during March to May and lowest during October to January. The most dominant families were Engraulidae (18.5%), Mugilidae (14.6%), Clupeidae (10.8%), Gobiidae (9.2%) and Cynoglossidae (7.4%). Ichthyoplankton samples from all three stations have similar species diversity indeces (FT = 0.56-1.19, mean 0.87) and evenness indeces (J' = 0.70-0.80, mean 0.75).

2 tables, 14 ref

013689   Hemapriya R;Sankar K;Imaran A D (Industries and Earth Sciences Dep, Tamil Univ, Thanjavur-613 010, Email: wonder_env@yahoo.com) : Geologic and geomorphologic investigation of Gadilam river basin (India). J Envir Res Dev 2010, 4(3), 750-7.

The study area (Gadilam river basin) lies between 79° 05' and 79°27' east longitude and between 11° 55' and 11° 45' north latitude covered Villupuram and Cuddalore district of Tamil Nadu. The basin area is demarcated from the survey of Indian topographical maps and covers an area about 860 km^{2. The problem of the present study is a representative case of overexploitation of groundwater resources, leading to the continuous exhaustion of the grained as well as the groundwater aquifers. The application of the increasingly and internationally accepted method of artificial recharge on the ground water aquifer was decided to be the most effective for the restoration of balance of the hydrogeological System. The details of Hydrological conditions of the area is necessary for the success of the method, whose planning has to be made based on the principles of environmental protection and sustainable development. Use of state -of-the-art technology and estimation of all the parameters involved, which are necessary, have been taken into account. Geological, geomorphological, landuse etc., investigation of the study area, which is necessary for groundwater resources evaluation has been digested well in this paper.}

6 illus, 9 ref

013688   Banerjee A;Masanta S (Soil & Water Conservation Dep, Bidhan Chandra Krishi Viswavidyalaya, Mohanpur-741 252, Email: shyamdulal_masanta@yahoo.co.in) : Effect of tsunami on some physico-chemical properties of soil under different land use systems of Nicobar islands. Envir Ecol 2009, 27(3), 1142-5.

Investigation was carried out during 2007-2008 of the existing Tsunami affected area under various land use system to study the changes occurred in physico-chemical properties of soil between pre-Tsunami and post-Tsunami period and to find out the effect of five different land use system. The results revealed that due to effect of Tsunami, soil texture, and soil reaction slightly changed i.e. sand percentage, bulk density, ph and EC Value increased whereas organic carbon, total nitrogen, available phosphorus and potassium content decreased. Among the different land use systems forest soil had low bulk density, high porosity and water holding capacity and high nutrient status in both pre-Tsunami and post-Tsunami period in respect of organic carbon percentage, total nitrogen and available phosphorus and potassium.

3 tables, 5 ref

012594   Sunil P S;Reddy C D;Ponraj M;Dhar A;Jaypaul D;Dharwadkar A (NO, Indian Institute of Geomagnetism, Kallamboli Highway, New Panvel, New Mumbai-410 218, Email: cdreddy@iigs.iigm.res.in) : Determination of the velocity vector of Schirmacher glacier (Dronning Maud Land Antarctica) using global positioning system. Indian J Geosci 2009, 63(2), 235-40.

Global Positioning System (GPS) has proved to be one of the most effective methods to measure glacier velocity. To give insight into the kinematics and quantitative understanding of the Schirmacher glacier (central Dronning Maud Land, Antarctica), two GPS campaigns were made during the austral summers of 2003 and 2004. GPS data were collected at 21 sites and have been analysed to estimate the site co-ordinates, baselines and velocities in ITRF2000. All the GPS points in the glacier have been constrained with the base station established at MAITRI, the Indian Antarctic Research Station and the nearby IGS stations, viz. VESL and SYOG. Displacement measurements were made from the GPS sites in Schirmacher glacier, parallel to the Schirmacher Oasis. The velocity of the sites is found to lie between 2 - 11 m yr-1 in NNE direction and the average velocity of the ice stream over the study region is 6.2 m yr-1. The site velocity distribution is spatially correlated to the surface undulation gradients, crevasses, and blockage of Schirmacher Oasis. In this paper, we report the glacier velocity vector derived from GPS and dynamic nature of the Schirmacher glacier.

4 illus, 1 table, 15 ref

012593   Subba Rao D V;Hussain S M;Balaram V;Moeen S; Naga Raju K (NO, National Geophysical Research Institute, Uppal Road, Hyderabad-500 007, Email: dvsubbarao3s@rediffmail.com) : Mineralogy, REE geochemistry and origin of the Proterozoic Gruber anorthosite massif in the Wohlthat ranges in East Antarctica. Indian J Geosci 2009, 63(2), 163-74.

Gruber Mountains in central Dronning Maud Land, East Antarctica exposes a typical Proterozoic massif-type anorthosite complex exposed over an area of approximately 900 sq km. Termed as Gruber anorthosite massif, it comprises monomineralic coarse-grained rock having homogeneous composition. The massif shows evidence of deformation and has also been intruded by lamprophyre, gabbro, pyroxenite and peridotite. It is associated with gabbronorites in the peripheral zone. Plagioclase is the dominant mineral phase present which has the composition of labradorite. The whole-rock composition too suggests dominance of plagioclase. Based on detail geochemical and petrochemical studies it has been indicated that the massif anorthosite has been derived from shallower mantle source having bulk composition of tholeiite through partial melting, leaving behind a pyroxene-dominant residue which was subsequently emplaced as norite. The Gruber anorthosite has comparable similarities with massif-type anorthosite complexes like the Nain anorthosite complex, Canada, the Adirondack anorthosite complex, USA and the massif-type anorthosite complexes exposed in Eastern Ghats and in the southern India granulite belt.

7 illus, 4 tables, 32 ref

012592   Shekhawat M S;Somani M K (Geology Dep, M.L. Sukhadia Univ, Udaipur-313 001) : Mineral economics of bauxite resources of Saurashtra region, Gujarat in light of amendments in mineral legislation. Indian J Geosci 2009, 63(3), 297-304.

The development and utilisation of bauxite resources of Saurashtra region, Gujarat represents a unique example caused mainly by positive changes in mineral legislation in the country. In the region, bauxite deposits are widely distributed and occur as irregular pockets of variable size within a zone of laterite derived from alteration of underlying Deccan Traps of Upper Cretaceous to Lower Eocene age. These deposits are being developed by open-cast, manual to semi-mechanised methods of mining on small-scale. Bauxite produced from the area is found suitable for its use mainly in metallurgical, refractory, abrasive and cement industries. The amendments made in mineral legislation in past two decades have played an important role in systematic development of this resource. Production and utilisation of bauxite of the region largely depends on export due to lack of any metallurgical plant in the State. The lifting of restriction imposed on export of this resource in export-import policy of the country with added advantage of sea-ports in the area has helped in increase in production and utilisation of the resource.

6 illus, 3 tabes, 20 ref

012591   Sesha Sai V V;Nathan N P;Vijay Kumar R; Balukkarasu A (Petrology Div, , Geological Survey of India, Kumud Villa Complex, Nongrim Hills, Shillong-793 003, Email: v.sai.gov.in) : Occurrence of PGE minerals in Archaean sittampundi layered anorthosite complex, Tamil Nadu, South India. Indian J Geosci 2009, 63(3), 305-10.

Ore microscopic studies revealed the presence of PGE minerals as inclusions within chrome-spinel-rich layers in pyroxenite bands occurring in the layered anorthosite in Karungalpatti and Chettiyampalayam blocks of Sittampundi layered anorthosite complex. Chrome-spinel, magnesio-chromite, magnetite, ilmenite and rutile are the oxide phases, while pentlandite, millerite and bravoite are the sulphide phases along with cobaltiferous pyrite noticed as inclusions. Sperrylite (PtAs₂), braggite (PtS) and stibiopalladinite (Pd, Cu)₅ Sb₂ are identified by ore microscopic studies, while kotulskite (palladium telluride) and laurite (RuS₂) have been confirmed by SEM-EDX studies. Rare grain of gold is noticed in chromite-rich amphibolite in Karungalpatti block. Based on detailed ore microscopic studies, modal analyses and mineral chemistry of bed rock and trench samples it is observed that the PGE minerals occur in the form of micron-sized inclusions (2 to 6 microns) in chrome-spinel cumulates. It is also noted that the higher the volume% of ore minerals particularly chrome-spinel with high MgO and relatively lower Cr₂O₃ contents, the higher the Pt-Pd mineralisation in Chettiyampalayam block.

2 illus, 3 tables, 10 ref

012590   Ravikant V (Geochronology and Isotope Geology Div, Geological Survey of India, , Email: vravi63@yahoo.com ) : Tectono-metamorphic history recorded in high-grade rocks from Filchnerfjella: further evidence for Pan-African reworking of the Grenville-aged crust in central Dronning Maud land, East Antarctica. Indian J Geosci 2009, 63(2), 141-52.

Bedrock exposed in Filchnerfjella comprises migmatitic gneissic biotite - hornblende granite with amphibolite boudins, intruded by peraluminous garnet-bearing alaskite. The garnet-bearing alaskite contains enclaves of deformed mafic granulite layers and migmatitic gneissic granite. The migmatitic gneissic granite shows contact with a sheet-like foliated charnockite and rare layers of garnet-sillimanite-cordierite-bearing metapelitic granulite occur at the contact of foliated charnockite and migmatitic gneissic granite. The rocks record imprints of high-grade tectono-metamorphic events, D₁/M₁ and D₂/M₂ followed by D₃ and D₄ deformation events. The dominant layering and foliation in the migmatitic gneissic granite represents a composite fabric (S₁//S₂) which trends E to ENE with moderate dips to the south and was the form surface deformed during D₂. The D₂ deformation resulted in formation of map-scale N- to NNW-vergent F₂ folds overturned to the south and development of mesoscopic-scale S₂ foliation in foliated charnockite and garnet-bearing alaskite. All the lithounits were later folded by regional F₃ folds formed during the D₃ deformation, which are upright, nearly cylindrical and have axial trace trending E-W resulting in the present-day map-pattern. N-S-trending F₄ folds have weakly deformed the F₃ axial trace. The gneissic granite and its amphibolite boudins preserve an amphibolite-facies imprint, whereas the retrograde P-T path inferred for the high-grade rocks comprises a near-isothermal decompression segment from near-peak granulite-facies conditions of 7-8 kbar and ≥700°C (M₁ -stage) to ~4.5 kbar and ~650-700° C (M₂-stage), recorded in metapelitic granulite and in boudins of mafic granulite. The protolith of the gneissic granite probably was emplaced around 1.1 Ga, as they are similar to the dated granodioritic rocks of adjacent Conradgebirge and Mhlig-Hofmann Mountains. The foliated charnockite yields a Rb-Sr whole-rock errorchron corresponding to an age of 536±56 Ma (MSWD=4.4) with Sr_i=0.7338±0.0007 and is interpreted broadly as time of cooling post-dating the syn-D₂ amphibolite-facies recrystallisation. Thus, it is very likely that this Pan-African timing for the major D₁/M₁ and M₂/D₂ events, with interleaved amphibolite-facies and granulite-facies rocks, links M₁ and M₂ metamorphic stages into a continuous path. This reworking of the Grenville-aged rocks, from the central Dronning Maud Land, is interpreted to have occurred due to collision of the ~1.1 Ga Coats Land-Maud-Grunehogna block with the East Antarctic craton followed by subsequent uplift.

6 illus, 3 tables, 40 ref

012589   Rajan S;Khare N;Pandey A;Pandey D K (NO, Ministry of Earth Sciences, New Delhi-110 003, Email: rajan@ncaor.org) : Proxies and pitfalls - the late quaternary glacial evolution of Schirmacher and Larsemann Oases, East Antarctica. Indian J Geosci 2009, 63(2), 215-20.

Despite a fairly vast paleoclimatic database, the mechanisms of millennial-scale global climate change remain an enigma. The reconstruction of the climatic and environmental history of the Antarctic region is primarily based on the proxy records in ice and lacustrine/marine sediment sequences. These records not only bring out the highly textured nature of the short-term climatic variability across Antarctica but also some significant differences in proximal areas. Two contrasting results from the two coastal oases of East Antarctica and the uncertainties with the available radiocarbon dates highlight not only the need for a multi-proxy, multi-site approach to deciphering the glacial history of Antarctica based on terrestrial records, but also on the need to exercise caution in translating the results from isolated Antarctic terrestrial records to the global scenario.

2 illus, 31 ref

012588   Pathan B M;Dhar A;Asinker R L;Selvamurugan R; Hanchinal A N (NO, Indian Institute of Geomagnetism, New Panvel, Navi Mumbai-410 218, Email: ajaydhar56@gmail.com) : Declining magnetic field at Maitri, Antarctica. Indian J Geosci 2009, 63(2), 187-94.

Earth's magnetic field is due to huge electric current circulating in the core of the Earth. Geomagnetic field is mostly dipolar in nature although multi poles also have some contribution. However, the main complication lies in the fact that there are a multitude of extraneous sources, which produce distortions in the magnetic field. As a consequence, the Earth's magnetic field is very complex which protects the Earth's surface and its inhabitants from hazardous cosmic radiation (energetic protons) received from the Sun. It is known that the Earth's magnetic field is decaying faster than any other worldwide geophysical phenomenon. This reported decrease is a major concern for the human kind. Will this continuous decrease lead to zero magnetic field sometimes in future? If so, how life on this planet will be affected? It is seen that the decline is mostly in the dipolar contribution. The decrease in magnetic field is not uniform all over the globe. It is reported that the geomagnetic field is declining in the Southern Hemisphere while in the Northern Hemisphere it is more or less steady or at a small increase. In the Southern Hemisphere too, the decrease is higher at certain locations. Indian Antarctic station, Maitri (Geog. 70.75° S, 11.75° E), is one such location recording a sharp decrease. Indian Institute of Geomagnetism is taking part in the annual Indian expeditions to Antarctica since its inception in 1981-82. A Proton Precession Magnetometer (PPM) is used to monitor the total magnetic field (F). It is seen that the magnetic field at Maitri has decreased by more than 2000 nT in the last 20 years. Geomagnetic field model reveals that the rate of decrease in the magnetic field at Maitri during the last century is about 105 nT/year. Maximum rate of decrease of about 120 nT/year is seen further north of this station. This result is discussed in terms of change of magnetic pole position, magnetic dipole moment and magnetic energy. It is seen that the decrease of energy in the dipole part has been, almost completely balanced by a corresponding increase in the energy of the non-dipole field. As a net result the energy of the total observed field measured all over the globe has remained almost constant. However, the magnetic moment has been found to change more rapidly at locations close to magnetic poles. Hence, the importance of continuous monitoring of total magnetic field at Maitri is emphasised.

10 illus, 1 table 16 ref

012587   Pant N C;Kundu A;Joshi S;Dey A;Bhandari A; Joshi A (Geology and Geophysics Dep, Indian Institute of Technology, Kharagpur-721 302epantnc@rediffmail.com) : Chemical dating of monazite - testing of an analytical protocol against independently dated standards. Indian J Geosci 2009, 63(3), 311-18.

Chemical dating of monazite using electron microprobe has gained widespread acceptance as a viable tool for quick generation of age-data but in spite of installations of several electron microprobe in India, little chemical-age data of monazite has been published. One of the reasons is the lack of well-dated external standards. This work presents a protocol for dating of monazite and exhibits its application by dating external age-standards ranging from 487 to 3132 Ma.

1 illus, 3 tables, 35 ref

012586   Panda P K;Panigrahi D (NO, , Geological Survey of India, Operation: Orissa, Bhubaneswar-751 012, Email: prayertojagannath@yahoo.co.in) : Petrochemistry and REE mineralogy of kankarakhol-lodhjhari alkaline complex, Deogarh district, Orissa. Indian J Geosci 2009, 63(3), 249-74.

The alkaline rocks of Kankarakhol-Lodhajhari belt in the Eastern Ghats terrain of Orissa constitute nepheline syenite as the dominant litho-member with minor proportion of other petrographic variants. The rocks are composed of variable proportions of microcline/orthoclase (Or_81.6-94.4), perthite (host potash feldspar, Or_81.1-93.1 with plagioclase lamellae of Ab_94.5-97.5), nepheline, plagioclase (Ab _86.5-99.3), amphibole (dominantly taramite), biotite and ± salite. The alkali amphibole taramite is the chief mafic mineral. Nepheline syenites are undersaturated, alkaline and miaskitic to marginally agpaitic in nature. Rare-earth-mineral phases, identified during the present study, are britholite-Ce, allanite-Ce, fergusonite-beta-Ce, monazite-Ce, bastnaesite-Ce, and RE-bearing pyrochlore and uranopyrochlore. The RE₂O₃ content is maximum (upto75.10%) in monazite-Ce and minimum in RE-oxides (up to 3.47%). The chondrite-normalised REE values show LREE enrichment and HREE depletion. The absence of Eu anomaly in the REE_N plots indicates no amount of plagioclase fractionation from the alkaline melt.

6 illus, 5 tables, 34 ref

012585   Nanda Kumar N V;Nagarjuna A;Reddy D C; Rajasekhar M;Mruthyunjaya Reddy K;Nageswara Rao A (Fishery Science and Aquaculture Dep, Sri Venkateswara Univ, Tirupati-517 502, Email: venkatananda_7@rediffmail.com) : Satellite remote sensing and ground level field studies on rayadouvu sea mouth of pulicat lake sanctuary and its ecological importance. Bioscan 2009, 4(2), 379-82.

Sea mouth at Rayadoruvu is gradually closing with sand bar formation due to blow of north bound wind as per satellite remote sensing imagery data from 2000-2006 and direct observational data showing sand bar formation for the year 2008 and 2009 is presented. Pulicat Lake requires immediate action for dredging as done for Chilka Lake. Construction of a groyne is recommended to prevent sea mouth closure by sand. Thus Rayadoruvu sea mouth passage is not simply a passage but also a biocorridor for migration offish, crustaceans, after spawning and breeding from lake to sea and vice versa acting as food for migratory long distant scheduled birds. The shallow water regimen is also an ideal niche during monsoon and also during post monsoon period upto March for fish and shrimp catch which has come down by 30% in 2009 and plankton density recorded was very less partially due to sea mouth shrinkage.

4 illus, 1 table, 8 ref

012584   Mukhopadhyay B;Dasgupta S;Acharyya A (NO, , Geological Survey of India, 27, Jawaharlal Nehru Road, Central Headquarters, Kolkata-700 016, Email: basabmukhopadhyay@yahoo.com) : Seasonal bias for the occurrence of shallow-focus earthquakes in the Indian tropics. Indian J Geosci 2009, 63(3), 327-32.

Incidence of shallow-focus (≤15 km) earthquakes in Indian subcontinent for magnitude mb ≥4.0 throughout the tropical seasons from January to December has been analysed for the earthquakes within time-period 1960 - June 2008. Earthquake occurrence has a peak in March. We propose a genetic correlation to explain such pattern following volume dilatancy - diffusion model. The infiltration of surface water within dilated seismogenic fault zones during rainy season initiates an enhanced pore pressure front by fluid-diffusion mechanism. This diffusion takes a phase lag of 9 months from the initiation month (June) to create pore-pressure perturbation on the seismogenic surfaces, and generates peak seismicity in March next year. Such seasonal fluctuations in pore pressure coupled with the periodic alteration in the gravitational pull due to Earth's rotation are some of the probable factors responsible for yielding maximum number of shallow-focus earthquakes in March.

2 illus, 131 ref

012583   Mohan A;Prakash D (NO, Dayalbagh Educational Institute, Dayalbagh, Agra-282 005, Email: anand.abhu@gmail.com) : UHT metamorphism in eastern ghats, India and East Antarctica vis-a-vis Gondwana connection. Indian J Geosci 2009, 63(2), 131-40.

As has been documented by the observations, Laboratory data and conceptual understanding of fundamental principles of geology, it has become clear that metamorphic petrology has much to contribute to the dynamics of major crustal processes. The concept of UHT metamorphism evolved gradually to explain some of the unusual granulite assemblages diagnostic of extreme P-T conditions. Initially such rocks reported from a few terrains were treated as rare rocks but today they dominate all continents of the world. There is no question that the application of cutting-edge technology, advanced instrumentation and laboratory techniques have been responsible for much of the progress made in last two decades in our understanding of UHT metamorphic rocks. It all started with careful and enlightened microscopic petrography. The Eastern Ghats Granulite Belt offers enormous scope to the practising metamorphic petrologists to polish their professional skills to the best of their capabilities. UHT metamorphism is an important tool in correlating the Eastern Ghats Belt of India with the Rayner complex of East Antarctica.

3 illus, 99 ref

012582   Mohakul J P;Saha A;Purushothaman D; Vidyadharan K T;Rajendran N (NO, , Geological Survey of India, Op: Orissa, Nayapalli, Bhubaneswar-751 012, Email: asit.saha@gsi.gov.in) : Geochemical mapping as a tool in reconnaissance survey: a case study in the State of Goa. Indian J Geosci 2009, 63(3), 287-96.

Geochemical mapping has been carried out using soil/laterite and stream sediment as media and the samples have been analysed by AAS, ICP-AES and ICP-MS. The statistical parameters are calculated for various elements present in soil and stream-sediment samples and their correlation is attempted. Geochemical maps showing the dispersion pattern of various elements in soils/laterite have been prepared. The Usgaon Ultramafic Complex is very well reflected in the geochemical map with anomalous values of chromium, nickel and cobalt. In addition to this, it has also brought to light two new areas exhibiting mafic-ultramafic signature. The geochemical maps for U, Th, Nb and Ta show a conspicuous anomalous pattern in the northwest part of Goa. The zones show a NE-SW trend, which is across the formational trend of NW-SE. Zirconium and hafnium distribution patterns have also brought out some anomalous zones. The copper distribution in stream sediment has shown anomalous values over the known occurrence associated with the Usgaon Ultramafic Complex and a number of other zones. Nickel shows similar pattern as that of copper. Lead shows two anomalous zones in the southern part. The study has shown usefulness of the regional geochemical maps in demarcating broad geochemical provinces for identifying the target areas for mineral prospecting. These maps can also be used as a base for geo-environmental studies.

5 illus, 4 tables, 13 ref

012581   Mishra O P;et al. (Geo-Seismology Div, CGD, Geological Survey of India, CHQ, Kolkata, Email: o.mishra@gsi.gov.in) : Preliminary note on the recent (late 2009) earthquakes around Koynain Maharashtra and their seismogenesis. Indian J Geosci 2009, 63(3), 333-8.

On November 14, 2009, two consecutive perceptible earthquakes of two different magnitudes (M_L 4.9 and 3.9) rocked the Koyna area of Maharashtra belonging to the stable peninsular part of Indian continental region (GSD, 2009). These two earthquakes were recorded by seismograph stations of Geological Survey of India (GSI) located at Nagpur, Lucknow, and Jabalpur. The preliminary determination of earthquake (PDE) data file was generated using individual seismogram recorded by these permanent seismograph stations. The PDE locations of the two events determined by single-station method demonstrate a good correlation with those generated by Indian Meteorological Department (IMD). The occurrence of these two events is closely related to the preexisting rupture zone of 10 December, 1967 Koyna earthquake (Mw 6.5). Sub-surface geometric dispositions of seismogenic faults beneath the Koyna region create a favourable environment for fault interactions where transfer of stress from one to another may have increased static stress. Based on the proximity of these two earthquakes of November 14, 2009 to the preexisting rupture zone, we infer that stress variability in the concealed conjugate fault system could have been an important cause of spawning earthquakes in the region. Loading and unloading of reservoir might have influenced the effective pore-fluid pressure by bringing drastic change in the confined pressure within fully pore-filled saturated rock matrix, which in turn, generated these two perceptible earthquakes.

8 illus, 1 table, 18 ref

012580   Kurtadikar M L;Kulkarni P G;Popalghat S K; Khare N (Physics Dep, J.E.S. College, Jalna-431 203, Email: mkurtadikar@yahoo.com) : Di-electric properties of Antarctic rocks around Maitri station. Indian J Geosci 2009, 63(2), 241-3.

Di-electric constant ∈ and di-electric loss ∈ of some of the rock samples from the locations around Maitri station in Antarctica are measured by using microwave bench set-up. These measurements are done at 5 GHz by using C-band automated bench. Also, the relative di-electric constant ∈_r is measured by using C-band automated microwave bench set-up at 9.6 GHz.

3 tables, 11 ref

012579   Kanthaiah S (NO, S.G.S. Govt. Degree & P.G. College, Jaggayyapet-521 175) : Water quality of Visakhapatnam steel plant (Also called jaggayyapet limestone mine). Acta Cienc Indica-Chem 2009, 35(3), 407-17.

Jaggayyapet Limestone mine is located about 470 kms away from the Visakhapatnam Steel Plant in Jaggayyapet, Krishna District in Andhra Pradesh. The mining area is situated at about 5 Km away from Hyderabad to Vijayawada national Hi way road (NH9). The paleru river is the source of drinking water for people of VSP Steel plant. In this paper, the author reports the quality of water in the Paleru river during the period, i.e., May 2002 to April 2003. For this study, the author selected the following 17 water quality parameters for analysis : 1. pH, 2. Electrical conductivity 3. Turbidity, 4. Total dissolved solids 5. Total suspended solids 6. Dissolved Oxygen 7. Bio-Chemical Oxygen demand, 8. Chemical Oxygen demand 9. Total coli form bacteria 10. Faecal coli form bacteria 11. Chlorides, 12. Sulphates, 13. Florides, 14. Total hardness 15. Ca-hardness, 16. Mg-hardness and 17. Alkalinity. The samples are collected on a monthly basis through out the year. The preliminary survey shows that the water of Paleru river at Visakhapatnam steel plant (Jaggayyapet lime stone mine) near Jaggayyapet town is not fit for human consumption without further treatment and disinfection since it contains a large number of both total and faecal coliforms through out the year.

17 illus, 1 table, 6 ref

012578   Joshi A;Pant N C (NO, Geological Survey of India, NH-5P, N.I.T., Faridabad-121 001, Email: joanil@rediffmail.com) : Petrological and geochemical evaluation of the anorthosite dykes from the Petermann ranges, Dronning Maud Land, East Antarctica: implications on anorthosite genesis. Indian J Geosci 2009, 63(2), 153-62.

Petrological and geochemical characteristics of the multiple anorthosite dykes that occur in the Petermann Ranges, East Antarctica, in spatial proximity to the Gruber anorthosite massif are reported for the first time. These dykes depict lower An content (An_32-52) in plagioclase and a hornblende-biotite-enriched composition in contrast to the orthopyroxene- dominated mafic mineral content of the massif anorthosite. These dykes also depict higher Na₂O and lower FeO and MgO contents in comparison to the Gruber anorthosite. A comparison with four other occurrences of anorthosite dykes from other parts of the world shows that all other dykes except those from Nain Plutonic Complex (NPC) contain hornblende and biotite as the main mafic minerals. The pyroxene-dominated anhydrous mineralogy of the NPC suggests its genetic linkage with the associated anorthosite plutons whereas the dykes of Petermann Range represent hydrous anatectic anorthosite formed probably by the partial melting of the gabbroic rocks of the charnockite suite by water fluxed melting during the 570-550-Ma metamorphic event in this region.

7 illus, 3 tables, 29 ref

012577   Gupta A (Palaeontology Div-I, Central Headquarters, , Geological Survey of India, 15 Kyd Street, Kolkata-700 016, Email: abirgupta@hotmail.com) : Ichthyofauna of the lower triassic panchet formation, Damodar valley basin, West Bengal, and its implications. Indian J Geosci 2009, 63(3), 275-86.

A diverse and abundant freshwater ichthyofauna has been recorded from the Lower Triassic Panchet Formation of Damodar valley basin, West Bengal. It is represented by numerous scales, teeth and tooth plates assigned to actinopterygian and dipnoi fishes and chondrichthyan shark, the latter being an important addition to the known global record of freshwater shark in the Lower Triassic. Some of the actinopterygian fish scales are comparable with those of the Arcadia Formation of Australia which is considered as older than the Lower Burgersdrop Formation of South Africa. This substantiates correlation of the Panchet Formation with the globally recognised Lootsbergian Land Vertebrate Faunachron. The new finds from the Panchet Formation refute the contention that the Lower Triassic freshwater actinopterygian fishes were endemic and support the view that the Gondwana landmasses were connected during the Lower Triassic.

21 illus, 31 ref

012576   Ghosh J B;Saha C;Roychowdhury P;Roy N K (Central Chemical Laboratory, Geological Survey of India, Kolkata-700 016, Email: j.ghosh@gsi.gov.in) : Rapid analysis of limestone and dolomite samples by pressed-pellet XRF technique. Indian J Geosci 2009, 63(3), 319-26.

A pressed-pellet XRF method is developed for rapid analysis of limestone and dolomite samples. Finely powdered 4.5 g (-200 mesh) of limestone and dolomite is pressed on a boric acid base in a hydraulic press at a pressure of 20-25 tons to obtain an uniform disk of 40-mm diameter. This pellet is irradiated and fluorescence is measured on aPhilips WD PW-2400 spectrometer using Rh end window X-ray tube. Eight international standard samples - three original standards, ECRM 782-1 (NIST), Jdo-1 (Japanese dolomite standard), Jls-1 (Japanese limestone standard) and five quartz mixed synthetic standards are used for calibration line. Two international standard samples - SRM 88b (dolomite) and SRM 1C (limestone) (both NIST) are analysed following the proposed method, and the results are quite in agreement with those of recommended values. The method, is routinely being used in Central Chemical Laboratory of Geological Survey of India for analysis of limestone and dolomite samples or any carbonate samples of these nature.

2 illus, 4 tables, 11 ref

012575   George A V;Koshy M (Post Graduate Dep of Chemistry, Christian College, Chengannur, Kerala) : Comparative study of trace metals in the sediments of rivers Manimala, Achancoil and Pamba in Pathanamthitta and Alappuzha districts of Kerala. Acta Cienc Indica-Chem 2009, 35(3), 339-49.

Rivers Manimala, Achancoil and Pamba are flowing through Pathanamthitta and Alappuzha districts of Kerala. In recent years considerable amount of work has been carried out in various lakes and estuaries and a good amount of information is available on the physical, chemical and biological aspects of water and bottom sediments. Attempts have been made to study the hydrography and biology of the River Pamba. But so far, no detailed studies have been made to compare the trace metals of rivers Manimala, Achancoil and Pamba. The trace metals in the sediments of rivers Manimala, Achancoil and Pamba were analysed for a period of one year from January 2007 to December 2007. The trace metals Copper, Zinc, Iron and Manganese showed low concentration in the three rivers as compared to other rivers. This might be due to low industrial pollution or point sources. The nature, source, flux and the dynamics of four metals were studied with a view to delineate the extent of pollution.

4 illus, 5 tables, 43 ref

012574   Chaturvedi S K;Khare N;Beg M J;Asthana R; Srivastava R;Mahesh R;Victor Rajamanickam G;Wangneo A (NO, Ministry of Earth Sciences, Block 12, CGO Complex, Lodhi Road, New Delhi-110 003, Email: chaturvedi@carism.sastra.edu) : Underwater geophysical survey of Antarctic lakes: challenges and implications. Indian J Geosci 2009, 63(2), 201-4.

Underwater geophysical survey in Antarctic lakes utilising acoustic techniques such as echo sounding and sub-bottom seismic reflection profiling provide vital information about the bathymetry and bottom topography of the lake and an estimation of the distribution, thickness and stratigraphy of the sediments underlying the lake floor. Such information assumes significance in the light of selecting suitable site for retrieving the sediment cores from lake bed, as the lake sediment offers exceptional potential to infer the past climatic conditions. Deals with a case study of the hydrographic survey in a lake in Antarctica using geophysical equipment (hydrobox echosounder) and discusses other underwater geophysical techniques and their feasibility to utilise the same for lake survey in one of the extremely difficult environments and unpredictable weather conditions.

4 illus, 5 ref

012573   Chaturvedi A;Shrivastava P K;Kaul M K; Chakraborty S K;Mukerji S (Antarctica Div, Geological Survey of India, NH 5P NIT, Faridabad-121 001, Email: arun.daak@gmail.com) : Recession of Dakshin Gangotri glacier snout in Schirmacher Oasis, East Antarctica. Indian J Geosci 2009, 63(2), 229-34.

Dakshin Gangotri (DG) glacier was identified in Schirmacher range in the year 1983 by the second Indian expedition to Antarctica. Since then its snout is being monitored every year. It was observed that the snout receded persistently at an average rate of 70 cm annually with minor departures. In 1996, for precise quantification of the rate of recession at fixed observation points, a total of 19 peripheral points were marked around the snout. With the quantification of data, now it is possible to plot the behaviour of the glacier at each point separately. It has been observed that the glacial front advances during the winter months, the upper layers of the glacier moving faster than the bottom layers. This results in a bulging of the advancing front, and then, with the arrival of the summer season, this bulge breaks off giving a net retreat. Studying the continuous data on recession available from 1996 to 2005 and the average annual ambient temperature of Schirmacher Oasis, it is proposed that the rate of recession of DG glacier is affected by the average annual ambient temperature recorded for the year previous to the year of observation.

5 illus, 2 tables, 9 ref

012572   Biswal T K;Ahuja H (Earth Sciences Dep, Indian Institute of Technology, Powai, Mumbai-400 076, Email: tkbiswal@iitb.ac.in) : Fold-thrust belt and synkinematic alkali magmatism along terrane boundary shear zone of the eastern ghats mobile belt: does the Rayner-Napier boundary of East Antarctica reflect that?. Indian J Geosci 2009, 63(2), 175-86.

Terrane margin of the Eastern Ghats Mobile Belt (EGMB) with the surrounding cratons of Indian Peninsula is considered to abut against the Rayner-Napier boundary of Enderby Land in the East Gondwanaland assembly. A detailed structural analysis of NW part of the Eastern Ghats terrane margin is attempted. The NW front shows fold-thrust belt structure consisting of Sinapalli, Lathore and Turekela nappes. The basal decollement is exposed as a terrane boundary shear zone that demarcates the high grade Eastern Ghats belt from the surrounding craton. It shows splay thrusts forming schuppen or imbricate structure. Further, the decollement passes over a lateral ramp across which a variation in the rock association is noticed. Nepheline syenite plutons are emplaced along the terrane boundary shear zone. The plutons show transitional fabric from magmatic to solid state, thus ascribing the compressional origin of the alkaline melt and synkinematic emplacement of the pluton with thrusting. The fold-thrust belt development and synkinematic alkaline magmatism characterising the NW margin of the EGMB should also be looked into the tectonic correlative Rayner-Napier boundary.

7 illus, 18 ref

012571   Bhandari S;Khare N (NO, , 1/13, Aashraya Apartments, Satya Marg, Ahmedabad-380 015, Email: satyendra_bhandari@yahoo.com) : Investigations of the seasonally oscillating edge over the southern ocean based on Oceansat-1 and QuikSCAT observations. Indian J Geosci 2009, 63(2), 221-8.

Characterising and understanding the variability of polar sea ice cover at different time scales is fundamental to our understanding of role of polar regions in global climate change. The large expanse of seasonally oscillating sea-ice cover around Antarctica is physically bounded by the continent on its poleward boundary and dynamically on its equatorward boundary by the strong Antarctic Circumpolar Current. Attempts to investigate the seasonal migration of the sea ice edge over the southern ocean between these two extremities, on a monthly scale using data from MSMR - the passive multi-frequency scanning microwave radiometer system onboard Oceansat-1. The location of sea ice edge is derived from weekly averaged MSMR 18- GHz H-polarisation channel brightness temperature images. Simultaneously available sea-ice information from SSM/I is used to validate the MSMR derived sea-ice parameters and to arrive at a brightness temperature threshold of 130 K to distinguish between sea ice and open water. It is observed that the amplitude of seasonal summer-to-winter N-S traverse of sea ice ranges from a few degrees of latitude to as much as about 15 degrees of latitude in different sectors of the southern Ocean around Antarctica. These amplitudes are largest over the Weddell Sea and Ross Sea regions. Further, the monthly rates of this migration show a non-uniform and oscillatory behaviour over the year and reach as high as 8-10 degrees of latitude per month just prior to the approach of summer and winter conditions. The observed seasonal variability shows connectivity to the behaviour of sea-ice edge over longer time scales. These observations have important implications for sea-ice interaction with climate. Recently, we have also embarked on use of higher-resolution active microwave scatterometer data from QuikSCAT to delineate the sea-ice edge more precisely. Preliminary results of these investigations are included.

6 illus, 1 table, 24 ref

012570   Bera S K (NO, Birbal Sahni Institute of Palaeobotany, 53, University Road, Lucknow-226 007, Email: skbera_2000@yahoo.com) : Sustained monitoring of long-distance transported palynodebris in Polar region: an interpretation for palaeoclimate reconstruction. Indian J Geosci 2009, 63(2), 195-200.

Evolution of the present-day terrestrial biota of the Antarctic and sub-Antarctic biomes has probably relied to a large extent on post-glacial immigration of propagules together with a small proportion of periglacial survival of viable propagules. In either case their success in developing and contributing to the sample ecosystems has had to rely on favourable environmental conditions for growth and reproduction. However, trans-oceanic dispersal must rely primarily on: 1) wind patterns and associated storm and precipitation events; 2) ocean currents; 3) birds, and 4) man. Although contamination cannot be entirely discounted, presence of such palynomorphs suggests steady rain of aerobiota over continental Antarctica. Present evidence of pollen spores, diatom and varia in air mass as well as various terrestrial and polar lake sediments (Zub and Long lake) of East Antarctica supports the dispersal system in other polar regions and inspires the idea for long-term monitoring of dispersal aspects across Southern Ocean and East Antarctic mainland which in turn will help in better understanding of palaeoclimatic reconstruction. Sustained monitoring of long-distance transported palynodebris across the Southern Ocean and Antarctic mainland should be developed in a broader way. As of now, only two years' aeropalynological data from Polar atmosphere are available in the context of Indian expeditions to East Antarctica since 1981 which register a fair range but sparse population of bioaerosols. Aerobiological studies of the whole Antarctic region require international cooperation and SCAR & BIOTAS research network have identified aerobiology as a major component of their international research programme which will be ground-, ship- and aircraft-based.

5 illus, 2 tables, 21 ref

012569   Asthana R;Shrivastava P K;Beg M J;Shome S; Kachroo K (NO, Geological Survey of India, NH-5P NIT, Faridabad-121 001, Email: asthana_rajesh2000@yahoo.com) : Surface microtextures of quartz grains from glaciolacustrine sediment core from Priyadrshini Lake, Schirmacher Oasis, East Antarctica as revealed under scanning electron microscope. Indian J Geosci 2009, 63(2), 205-14.

Surface microtextures of quartz grains have been used as an important tool for interpreting transportation and depositional history of detrital sediments. Quartz grains from five segments of a 32-cm-long, undisturbed sediment core retrieved from Priyadarshini Lake have been studied under scanning electron microscope. Debris supplied by ice mass through melt-water streams embouching in the lake and windborne sediments are present in the cores obtained irrespective of their various segments. The sediment column consists of relatively fine-grained material because the water is almost stagnant or has a low flow velocity, enabling even the finest particles to get settled. Various microtextures and microtopographical information observed on the quartz grain surfaces indicate predominance of intense mechanical textures characteristic of glacial transport. Most often several stages of crushing and weathering are noted. Grains are mostly angular to subangular having high relief, large conchoidal fractures, deep troughs, arcuate fracture patterns, subparallel and parallel steps, striations, breakage blocks, adhering particles, oriented scratches and grooves belonging to glacial origin. Dish-shaped concavities, small conchoidal fractures, collision pits, edge rounding are attributed to aeolian transport of grains. Features related to chemical origin are represented by mild dissolution etching and silica precipitation in the form of amorphous and cryptocrystalline overgrowth suggesting precipitation on immobile grains under lacustrine environment. The assemblage of microtextures exhibiting multiple events of glacial crushing overprinted on single grains and different degrees of dissolution features that are discernible are grouped and discussed.

7 illus, 1 table, 21 ref

011665   Shamsul ALam M;Ahmed R (Geography and Environmental Studies, Rajshahi Univ, Rajshahi 6205, Bangladesh, Email: alam_ges@ru.ac.bd) : Tropical cyclones in Bangladesh. Trans Inst Indian Geogr 2009, 31(1), 37-47.

Bangladesh is one of the most cyclone-prone countries in the world. Tropical cyclones that hit the coastal areas of Bangladesh from 1960 through 2004 have been statistically analyzed and presented in this paper. During this 45-year period, 22 cyclones hit Bangladesh, with a frequency of one every two years. Of these 22 cyclones, 6 were category 1 cyclones (27.3%), 9 were category 2 (41%), 3 were category 3 (13.6%), 3 were category 4 (13.6%), and 1 was a category 5 cyclone (4.5%). Of the 22 cyclones, 9 (41%) occurred during the pre-monsoon season (April-May), and 13 (59%) during the post-monsoon season (end of September to mid-December), and none during the summer monsoon season (June-September). The coastal zone from the Feni River to Teknaf (the southeast corner of the country) is the most cyclone-prone region in the country, which accounts for 68% of the cyclone occurrences (15 out of 22).

4 illus, 3 tables, 19 ref

011664   Patil R;Sinha Ray K C;Pradeep Kumar P (Physics Dep, Pune Univ, Pune-411 007) : Simulation of the winter precipitation and temperature over western Himalayas using varsha GCM. Bionano Front 2010, ICLAM(spl), 55-8.

Northern India is comprised of complex Himalayan mountain ranges having different altitude and orientations This highly variable terrain is responsible for complexity of the weather systems passing over the region. During winter season, large amount of precipitation is received in this region due to eastward moving Sow pressure synoptic weather systems called Western Disturbances In this study an attempt is made to simulate each month during winter (December, January, February, March) for the period 2000-2008.. The VARSHA model output of precipitation was compared with the IMD's 1° x 1° gridded precipitation data for the period 2000 to 2004 and with the TRMM data for the period 2005 to 2008. The model output of Temperature was compared with the IMD's 1°x1° gridded minimum temperature data period 2000 the period to 2005 and 2008.

1 table, 9 ref

011663   Patil K D (Geography Dep, G.T. Patil College, Nandurbar-425 412) : Physico-chemical charecteristics of ground water in Amravati-Bhad basin of Nandurbar district, Maharashtra. Asian J chem envir Res 2009, 2(3-4), 82-6.

The physico-chemical characteristics of ground water in the Amravati- Bhad Basin of Nandurbar District have been studied. Twenty two water samples representing the ground water of the study area were collected and analyzed. The major physical constituents of natural water like, temperature, pH, total dissolved solids and electrical conductivity and chemical constituents like sodium(Na ^{+ +), Potassium(K + ), Calcium(Ca + ) and Magnesium(Mg+), Carbonate(CO₃), bicarbonates(HCO₃-), Chlorides(Cl-), Sulphates(SO₄2-) were analyzed. An Attempt is made to classify the dominant cations and anions in the ground water of the study area.}

5 illus, 2 tables, 81 ref

011662   Karanjot Kaur Brar (Geography Dep, Panjab Univ, Chandigarh) : Geomorphic expressions of the main boundary fault: a study of the Kasauli ridge area (Shimla hills, Himachal Pradesh). Trans Inst Indian Geogr 2009, 31(1), 81-93.

The Himalayas are a seismically active zone with innumerable faults. Faulting commonly has topographic expression. This is a study of the geomorphic expressions of the Main Boundary Fault in the Himalayas in the vicinity of the Kasauli Ridge area, Shimla Hills, from the Survey of India topographical sheet: 53 B/I3. An intensive study was made of the drainage, springs, and the river terraces; slope analysis of the study area was done and profiles made for topographic interpretation. The evidence of the Main Boundary Fault was seen in the extreme steepness of slope and presence of scarp faces in the proximity of the Fault, the angular bends in the streams, the sudden breaks in slope in the longitudinal profiles of the rivers, the significant difference in slope on either side of the fault and presence of springs and terraces.

6 illus, 1 table, 3 ref

011661   Joshi V U (Geography Dep, Pune Univ, Pune-411 007, Email: vujoshi@unipune.ernet.in) : Scour depth estimation based on the physical properties of soil along the tributaries of river Pravara, Maharashtra. Trans Inst Indian Geogr 2009, 31(1), 71-80.

The estimation of scour depth around bridge piers and abutments is a common practice in Engineering Geology. The local lowering of the riverbeds around the elements of a bridge such as piers, abutments and spur dikes is what is termed as 'scour', which is influenced by the local factors, prevailing in a particular area. -fir This concept has been applied to riverine badland topography to determine the possible depth up to which the river will sour the sediments. Lacey-Inglis's Method has been adopted to estimate the scour depth. The soil physical properties as well as K erodibility index suggest that these soils are fairly to moderately erodible and the estimated scour depth is between 3-4 m. Though the calculated values show extreme conditions under the prevailing set of conditions, it gives a fairly good estimate of the sediment's erodible depth. Recently the area is undergoing rapid land reclamation for the purpose of agriculture, hence evaluation of its properties are relevant to understand the susceptibility of the sediments to erosion.

2 illus, 4 tables, 14 ref

011660   Hassan S M;Adefolalu D O;Sani M (Geography Dep, Abuja Univ, Nigeria) : Recent rainfall trends in the FCT, Abuja. Trans Inst Indian Geogr 2009, 31(1), 49-56.

Certain anomalies within the surface hydrology of the study area prompted the authors to take a critical look of the trend and pattern of rainfall in the past two decades. The derived characteristics of rainfall are obtained and analyzed in order to see salient features of rainfall that are not made visible through copious amount. The specific methods are; Precipitation Periodicity Index (PPl), Onset, Cessation and Length of Rainy Season and Rainfall Intensity. The result obtained showed that the rainfall in the FCT has been declining within the past two decades. This is observed through the monthly, annual average and departure from the mean rainfall. The result also reveal the unique characteristic of rainfall increasing from the south to north in the FCT rather than decreasing in that direction as dictated by the general climatology of the country.

5 illus, 9 ref

011659   Chen C N;Wang J L;Chu C M;Lu F C (Military Acacemy, Republic of China, China) : Ray-trace of an abnormal radar echo using geographic information system. Def Sci J 2009, 59(1), 63-72.

Weather radar plays a key role in natural disaster mitigation just as surveillance radar does in detecting objects that threaten homeland security. Both together comprise an instrumental part of radar observation. Therefore, quality control of the data gathered through radar detection is extremely important. However, radar waves propagate in the atmosphere, and an anomalous echo can occur if there are significant discontinuities in temperature and humidity in the lower boundary layer. The refractive curvature of the earth makes some errors in observation inevitable. On the night of July 3, 2003, Next Generation Radar (NEXRAD) weather radar detected an abnormal echo. The Weather Research and Forecast (WRF) model was utili/.cd to simulate the atmospheric conditions. Radar propagation was simulated using the Advanced Refractivity Engineering Prediction System (AREPS) as well as the GIS. The results show the feasibility of establishing an abnormal propagation early-warning system and extending the application of the GIS in serving as the foundation of a Common Operation Picture (COP). Furthermore, the parameters of the boundary layer near the sea's surface in the numerical weather forecasting model need remodification.

9 illus, 1 table, 35 ref

010507   Yong A;Hough S E;Abrams M J;Wills C J (NO, , 525 South Wilson Avenue. Pasadena, CA 91106, USA, Email: yong@usgs.gov) : Preliminary results for a semi-automated quantification of site effects using geomorphometry and ASTER satellite data for Mozambique, Pakistan and Turkey. J Earth Syst Sci 2008, 117(S2), 797-808.

Estimation of the degree of local seismic wave amplification (site effects) requires precise informaion about the local site conditions. n many regions of the world, local geologic information is either parse or is not readily available. Because of this, seismic hazard maps for countries such as Mozambique, Pakistan and Turkey are developed without consideration of site factors and, therefore, do not provide a complete assessment of future hazards. Where local geologic information is available, details on the traditional maps often lack the precision (better than 1:10,000 scale) or the level f information required for modern seismic microzonation requirements. Uses high-resolution 1:50,000) satellite imagery and newly developed image analysis methods {o begin addressing this problem. Consisting of optical data and digital elevation models (DEMs), is recorded from the ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) sensor system. Applies semi-automated, object-oriented, multi-resolution feature segmentation method o identify and extract local terrain features. Then we classify the terrain types into mountain, piedmont and basin units using geomorphometry (topographic slope) as our parameter. Next, on the basis of the site classification schemes from the Wills and Silva (1998) study and the Wills et al (2000) and Wills and Clahan (2006) maps of California, we assign the local terrain units with V_s30 (the average seismic shear-wave velocity through the upper 30 m of the subsurface) ranges for selected regions in Mozam ique, Pakistan and Turkey. It has been finds that the applicability of our site class assignments in each region is a good first-approximation for quantifying local site conditions and that additional work, such as the verification of the terrain's compositional rigidity, is needed.

15 illus, 2 tables, 42 ref

010506   Wang Z (Kentucky Geology Survey, University of Kentucky, Lexington, Kentucky-40506, USA, Email: zmwang@uky.edu) : Technical note on seismic microzonation in the central United States. J Earth Syst Sci 2008, 117(S2), 749-56.

Microzonation is an effort to evaluate and map potential hazards found in an area, urban area in particular. that could be induced by strong ground shaking during an earthquake. These hazards include ground motion amplification, liquefaction, and slope failure. The microzonation maps, depicting ground-motion amplification, liquefaction, and landslide potentials, can be produced if ground motion on bedrock (input) and the site conditions are known. These maps, in combination with ground-motion hazard maps (on bedrock), can be used to develop a variety of hazard mitigation strategies such as seismic risk assessment, emergency response and preparedness, and land-use planning. However, these maps have certain limitations that result from the nature of regional mapping, data limitations, generalization, and computer modeling. These microzonations show that when strong ground shaking occurs, damage is more likely to occur, or be more severe, the higher hazard areas. The zones shown on the hazard maps should not serve as a substitute for site-specific evaluations.

3 illus, 2 tables, 47 ref

010505   Turnbull M L (Faculty of Business and Informatics, Central Queensland University, Bundaberg D C, Queensland, Australia, Email: M.Turnbull.cqu.edu.au) : Relative seismic shaking vulnerability microzonation using an adaptation of the Nakamura horizontal to vertical spectral ratio method. J Earth Syst Sci 2008, 117(S2), 879-95.

An alternative seismic shaking vulnerability survey method to .computational intensive theoretical modelling of site response to earthquake, and time consuming test versus reference site horizontal ratio methods, is described. The methodology is suitable for small to large scale engineering investigations. Relative seismic shaking vulnerability microzonation using an adaptation of the Nakamura horizontal to vertical spectral ratio method provides many advantages over alternative methods including: low cost; rapid field phase (l00km^{2 can easily be covered by a single operator in 5 days); low and flexible instrumentation requirements (a single seismometer and data logger of almost any type is required); field data can be collected at any time during the day or night (the results are insensitive to ambient social noise); no basement rock reference site is required (thus eliminating trigger synchronisation between reference and multiple test site seismographs); rapid software aided analysis; insensitivity to ground-shaking resonance peaks; ability to compare results obtained from non-contiguous survey fields. The methodology is described in detail, and a practical case study is provided, including mapped results. The resulting microzonation maps indicate the relative seismic shaking vulnerability for built structures of different height categories within adjacent zones, with a resolution of approximately 1 km.}

15 illus, 3 tables, 42 ref

010504   Raghu Kanth S T G (Civil Engineering Dep, Indian Institute of Technology, Madras, Email: raghu_stg@yahoo.com) : Modeling and synthesis of strong ground motion. J Earth Syst Sci 2008, 117(S2), 683-705.

Success of earthquake resistant design practices critically depends on how accurately the future ground motion can be determined at a desired site. But very limited recorded data are available about ground motion in India for engineers to rely upon. To identify the needs of engineers, under such circumstances, in estimating ground motion time histories, this article presents a detailed review of literature on modeling and synthesis of strong ground motion data. In particular, modeling of seismic sources and earth medium, analytical and empirical, Greens functions approaches for ground motion simulation, stochastic models for strong motion and ground motion relations are covered. These models can be used to generate realistic near-field and far-field ground motion in regions lacking strong motion data. Numerical examples are shown for illustration by taking Kutch earthquake-200l as a case study.

11 illus, 3 tables, 92 ref

010503   Prabhu S;Kulkarni N (NO, Maharshi Dayanand College, Parel, Mumbai, Maharashtra, Email: drneelimakulkarni@gmail.com) : Assessment of water quality at Dadar beach, Mumbai, Maharashtra, West coast of India. Bionano Front 2010, 3(1), 59-63.

As a coastal city Mumbai has a whole lot of beaches along its western frontier. Dadar is a centrally located recreational beach for public, it is also one of the major sinks on the west coast of Indian subcontinent (Govindan, 1980; Deshmukh, 2002). Quality and area of beach have been steadily degrading due to inappropriate construction activities too close to the beach. Exploitation of shoreline and near shore environment for transportation, residential development and release of effluents, disrupt natural sedimentation movements in variety of ways causing accelerated erosion. Regular monitoring of coastal water quality plays an important role in detection and evaluation of coastal water pollution. Present study was conducted at two fixed stations on 2 km stretch of Dadar beach starting from Baji Prabhu Udyan, towards Northern end to Tata tele services on Southern end. Surface water and sediment samples were collected on the eighth day of lunar cycle (ashatmi) from mid littoral zone to study hydrology for the period of 12 months (October 2007 to September 2008). Water sample was analysed for its Physicochemical parameters such as temperature, pH, salinity DO, BOD, COD, phosphates, nitrites, and ammonium using standard methods (Standard methods for examination of water and waste water, APHA, 18th Ed.) with suitable modifications. Present study indicated that variables of water parameters follow activity based (pollution) and seasonal variations. However sediment analysis showed faster silting at one station as compared to the other.

7 illus, 12 ref

010502   Nath S K;Thingbaijam K K S;Raj A (Geology and Geophysics Dep, Indian Institute of Technology, Kharagpur-721 302, Email: nath@gg.iitkgp.ernet.in) : Earthquake hazard in Northeast India - a seismic microzonation approach with typical case studies from Sikkim Himalaya and Guwahati city. J Earth Syst Sci 2008, 117(S2), 809-31.

The microzonation approach involves multi-criteria seismic hazard evaluation through thematic integration of contributing factors. The geomorphological themes for Sikkim Himalaya include surface geology, soil cover, slope, rock outcrop and landslide integrated to achieve geological hazard distribution. Seismological themes, namely surface. consistent peak ground acceleration and predominant frequency were, thereafter, overlaid on and added with the geological hazard distribution to obtain the seismic hazard microzonation map of the Sikkim Himalaya. On the other hand, the microzonalion study of Guwahati city accounts for eight themes - geological and geomorphological, basement or bedrock, landuse, landslide, factor of safety for soil stability, shear wave velocity, predominant frequency, and surface consistent peak ground acceleration. The five broad qualitative hazard classifications - `low', `moderate', `high', `moderate high' and `very high' could be applied in both the cases, albeit with different implications to peak ground acceleration variations. These developed hazard maps offer better representation of the local specific seismic hazard variation in the terrain.

10 illus, 5 tables, 46 ref

010501   Nath S K;Shukla K;Vyas M (Dep of Geology and Geophysics, Indian Institute of Technology, Kharagpur-721 302, Email: nath@gg.iitkgp.ernet.in) : Seismic hazard scenario and attenuation model of the Garhwal Himalaya using near-field synthesis from weak motion seismometry. J Earth Syst Sci 2008, 117(S2), 649-70.

Presents a seismic hazard scenario for the Garhwal region of the north-western Himalayan range, in terms of the horizontal Peak Ground Acceleration. The scenario earthquake of moment magnitude M_w 8.5 has a 10% exceedance probability over the next 50 years. These estimates, the first for the region, were calculated through a stepwise process based on an estimation of the Maximum Credible Earthquake from the seismicity of the region and Global Seismic Hazard Assessment Program considerations, and four seismotectonic parameters abstracted from near field weak-motion data recorded at five stations installed in Chamoli District of the Garhwal region in the aftermath of the 1999 Chamoli earthquake. The latter include the frequency dependent power law for the shear wave quality factor, Q_s, the site amplification at each station using horizontal-to-vertical-spectral ratio and generalized inversion technique, source parameters of various events recorded by the array and application of the resulting relations between the scalar seismic moment M_o (dyne-cm) and moment magnitude M_ww and the corner frequency, f_c (Hz) and moment magnitude M_w to simulate spectral acceleration due to higher magnitude events corresponding to the estimated Maximum Credible Earthquake. and regional and site specific local spectral attenuation relations at different geometrically central frequencies in the low, moderate and high frequency bands.

21 illus, 7 tables, 44 ref

010500   Luke B; (Univ of Nevada Las Vegas, , Las Vegas, Nevada 89154-4015, USA, Email: barbara.luke@unlv.ed) : Site response zones and short-period earthquake ground motion projections for the Las Vegas Basin. J Earth Syst Sci 2008, 117(S2), 757-72.

A deterrministic seismic hazard analysis was conducted to address the effect of local soil conditions on earthquake-induced strong ground motion in the Las Vegas Basin, Nevada (US). Using a large geological and geotechnical database, two response units were defined: a fine-grained unit, predomy clay; and a coarse-grained unit, predominantly gravel. A moderate number of high-quality shallow shear wave velocity measurements were collected from which characteristic shear wave velocity profiles were developed for each response unit. An equivalent-linear one-dimensional site response model was used. The model was calibrated using a basin-wide, small-strain ground motion database. Calibration tests showed that ground motion projections become increasingly conservative increasing ground-motion amplitude. Projections were overconservative for the coarse-grained response unit, likely due to the sparseness' of the velocity database. For the earthquake response analyses, historical ground motions were used to model characteristic 'bedrock' motion for earthquakes on 10 faults judged to be critical. Response spectral envelopes were generated for unit through Monte-Carlo simulations. For the fine-grained response unit, 95th percentile ground acceleration, peak spectral acceleration and predominant period were 310 cm/s^{2, 1100 cm/s2, and 0.29s, respectively. With respect to codified design spectra, projections are lower at short periods and higher at long periods. Projections ofpeak spectral accelerations for the coarse-grained response unit, were more than double that of codified spectra; however, they are believed to overconservative. Near-fault effects and basin-edge effects, though potentially important, were not considered in these analyses.}

18 illus, 3 tables, 44 ref

010499   Kumar S;Narayan J P (Eearthquake Engineering Dep, Indian Institute of Technology Roorkee, Roorkee-247 667, Email: jaypnfeq@iitr.ernet.in) : Importance of quantification of local site effects based on wave propagation in seismic microzonation. J Earth Syst Sci 2008, 117(S2), 731-48.

Presents the three most important aspects of seismic microzonation namely prediction of fundamental frequency (F_o) of soil deposit, aggravation factor (aggravation factor is simply the extra spectral amplification due to complex 2D site effects over the 1D response of the soil column) and the spatial variability of the ground motion caused by the basin-edge induced Love waves. The predicted F_o of single. double and three-soil-layered models revealed that the available empirical ns to predict the F_o of layered soil deposits are inadequate. It has been recommend the use of analytical or numerical methods to predict such an important parameter based on wave propagation . An increase of amplitude of Love wave, strain level and average aggravation factor (AAF) increase of impedance contrast was obtained. Based on the trend of rate of decrease of AAF maximum strain with offset from the basin-edge, we can qualitatively infer that the effects of Love wave may reduce to a negligible value after a traveled distance of 6.5-10.0 λ_F (where λ_F is the wavelength corresponding to the F_o of soil layer). The obtained increase of strain level the decrease of distance between two receiver points used for the computation of strain reflects that structures having spatial extent smaller than the λ_F may suffer damage due to the basin-edge red surface waves. The fast rate of decrease of strain with the offset from the strong lateral discontinuity (SLD)/basin-edge may be attributed to the dispersive nature of Love wave. Incorporates the increased spectral amplification due to the induced surface waves in the form of aggravation factor but till date we have no effective way to incorporate the effects of developed .strain by induced surface waves in seismic microzonation or in building codes.

16 illus, 5 tables, 24 ref

010498   Kamalian M;Sohrabi-bidar A;Razmkhah A;Taghavi A;Rahmani I (Geotechnical Engineering Research Centre, International Institute of Earthquake Engineering and Seismology, 26 Arghaan St. North Dibajee, Farmanieh, Tehran, I.R. Iran) : Considerations on seismic microzonation in areas with two-dimensional hills. J Earth Syst Sci 2008, 117(S2), 783-96.

Presents the results of an extensive numerical parametric study on seismic behavior of 2D homogenous hills subjected to vertically propagating incident SV waves. It is shown that he amplification potential of these hills is strongly influenced by the wavelength, by the shape ratio, by the shape of the hill and in a less order of importance, by the Poisson ratio of the media. The 2D topography effect could be ignored, only if the hill has a shape ratio of less than 0.1 or if it is subjected to incident waves with predominant dimensionless periods of greater than 13 times the shape ratio. In incidence of waves with wavelengths longer than the width of the hill, he amplification curve usually finds its maximum at the crest and decreases towards the base of the hill. Else, some de-amplification zones would occur along the hill. Among hills with similar shape ratios, those with intermediate cross section areas show intermediate seismic behavior, too. Estimated seismic site coefficients for the crest of a 2D rocky hill depend on its shape ratio and could reach even 1.7, which encourages one to classify it according to standard site categorization procedures as soil profile types SC or SD instead of the conventional SB type.

15 illus, 5 tables, 41 ref

010497   Joshi G C;Sharma M L (NO, Indian Institute of Technology Roorkee, Roorkee-247 667, Email: mukutfeq@iitr.ernet.in) : Uncertainties in the estimation of Mmax. J Earth Syst Sci 2008, 117(S2), 671-82.

The parameters affecting the uncertainties on the estimation of M_max have been investigated by exploring different methodologies being used in the analysis of seismicity catalogue and estimation of seismicity parameters. A critical issue to be addressed before any scientific analysis is to assess the quality, consistency, and homogeneity of the data. The empirical relationships between different magnitude scales have been used for conversions for homogenization of seismicity catalogues to be used for further seismic hazard assessment studies. An endeavour has been made to quantify the uncertainties due to magnitude conversions and the seismic hazard parameters are then estimated using different methods to consider the epistemic uncertainty in the process. The study area chosen is around Delhi. The b value and the magnitude of completeness for the four seismogenic sources considered around Delhi varied more than 409( using the three catalogues compiled based on different magnitude conversion relationships. The effect of the uncertainties has been then shown on the estimation of M_max and the probabilities of occurrence of different magnitudes. It has been emphasized to consider the uncertainties and their quantification to carry out seismic hazard assessment and in turn the seismic microzonation.

2 illus, 3 tables, 31 ref

010496   Jaiswal K;Sinha R (Civil Engineering Dep, Indian Institute of Technology Bombay, Powai, Mumbai-400 076, Email: kishorjaiswal@gmail.com) : Spatial-temporal variability of seismic hazard in peninsular India. J Earth Syst Sci 2008, 117(S2), 707-18.

Examines the variability of seismic activity observed in the case of different geological India (l0°N-26°N;68μE-90<109>E) based on earthquake catalog between the period and estimates earthquake hazard for the region. With compilation of earthquake of moment magnitude and establishing broad completeness criteria, we derive parameters for each geologic zone of peninsular India using maximum likelihood estimated parameters provide the basis for understanding the historical seismicity h different geological zones of peninsular India and also provide important inputs for hazard estimation studies in the region. Based on investigation, it is clear recurrence activity in various geologic zones of peninsular India is distinct and ably between its cratonic and rifting zones. The study identifies the likely hazards due to the possibility of moderate to large earthquakes in peninsular India and also presents the spatial rate variation in the seismic activity of this region. Presents the influence of source zone characterization and recurrence rate variation pattern on the maximum magnitude estimation. The results presented provide a useful basis for seismic hazard studies and microzonation studies in peninsular India.

8 illus, 2 tables, 37 ref

010495   Irsyam M;Dangkua D T;Hendriyawan;Hoedajanto D;Hutapea B M;Kertapati E K;Boen T;Petersen M D (Civil and Environmental Engineering Faculty, Institut Teknologi Bandung, Jl. Ganesha 10 Bandung, West Java) : Proposed seismic hazard maps of Sumatra and Java islands and microzonation study of Jakarta city, Indonesia. J Earth Syst Sci 2008, 117(S2), 865-78.

Presents the development of spectral hazard maps for Sumatra and Java islands, Indonesia and micro zonation study for Jakarta city. The purpose of study is to propose a revision of the seismic hazard map in Indonesian Seismic Code SNI 03-1726-2002. Some improvements in seismic hazard analysis were implemented in the analysis by considering the recent seismic activities around Java and Sumatra. The seismic hazard analysis was carried out using 3-dimension (3-D) seismic source models (fault source model) using the latest researc4 works regarding the tectonic setting of Sumatra and Java. Two hazard levels were analysed for representing 10% and 2% ( probability of exceedance (PE) in 50 years ground motions for Sumatra and Java. Peak ground acceleration contour maps for those two hazard levels and two additional macrozonation maps for 10 PE in 50 years were produced during this research. These two additional maps represent short period (0.2 s) and long-period (1.0 s) spectra values at the bedrock. Microzonation study is performed in order to obtain ground motion parameters such as acceleration, amplification factor and response spectra at the surface of Jakarta. The analyses were carried out using nonlinear approach. The results were used to develop contour of acceleration at the surface of Jakarta. Finally, the design response spectra for structural design purposes are proposed.

15 illus, 57 ref