023065   Rajendra Prasad B;Rao G K (National Geophysical Research Institute, , Uppal Road, Hyderabad-500007) : Effective criteria to assess seismic source efficiency in poor signal to noise conditions in a trap covered region. J Indian Geophys Union 2003, 7(3, 155-8.

NGRI had taken up an ambitious project for imaging subtrappean sediments in Deccan Syneclise. As a routine, the team had conducted certain experimental recordings in the eara. The experiment consisted of shooting different charge sizes (350 and 600 kg) in sepcially drilled shot holes with charge placed at an average depth of 23 meters. Care has been taken to place the charge in similar geological environments and near by locations. The seismic records are processed on Promax 2003 with the aim of styding the energy contnent and the amplitude decay with offset. Even though, it appeared that the quality of seismic monitor record with 350kg charge size is better than that of 600 kg, the study of average trace amplitude, its decay and amplitude spectrum of noise free traces have shown, as expected, that the record quality of 600 kg charge size stands better. The technique is verified in poor S/N conditions. The misleading impression from monitor record of 350 kg can be attributed to the random noise conditions.

7 illus, tables, 2 ref

023064   Pillai K G M;Dabas R S;Veenadhari B;Lakshmi D R (National Physical Laboratory, , New Delhi-110012) : The scientific basis for solar-terrestrial predictions at Natinal Physical Laboratory, New Delhi. J Indian Geophys Union 2003, 7(3), 159-65.

Solar-Terrestrial Predictions are essential to plan a variety of systems including communication and navigation, Earth orbiting satellites and other space missions. The paper describes the prediction services porvided by the National Physical Laboratory, New Delhi, which incidentally is the only source in India for such predictions. The paper also gives examples of some innovative approaches introduced to improve the prediction accuracy such as Equatorial Electrojet strength as an index in ionospheric predictions. The recent controversies regarding the contribution of natural solar variability vis-as-vis anthropogenic sources in global/climate change have also enhanced the interest of the Geophysical community in fine-tuning Solar-Terrestrial Predictions.

6 illus, tables, 24 ref

023063   Patil V D;Phulari P S (Civil Eng Dep, Govt. College of Eng., Pune-411005) : Cathodic protection system for underground M.S. pipeline of watersupply project. Indian J envir Hlth 2003, 45(1), 11-4.

Corrosion of steel embedded in soil can generally be explained in terms of long cell action arising from differential acration. The significant factors to promote corrosion are soil potential, Resistivity and draining characteristics. As the corrosive nature of soil is not fixed absolute value, the said study can be analyzed by adopting the following methodology. Study of state of soil at different locaton, nature of corrosion under consideration. With above methodology an attempt can be made to achieve the following objective to, assess the extent of corrosive tendencies of soil along the pipelline. Co-relate potential an dresistivity with corrosive parameters of soil and suggest the appropriate remedial means for protecting it from corrosion, i.e., Galvanic activity.

illus, 3 tables, 11 ref

023062   Pathak V;Mahavar L R;Sarkar A (Central Inland Capture Fisheries Res Inst, 24, Panna Lal Road, Allahabad-211 002, ) : Ecological status and production dynamics of a stretch of river Mahanadi. J Inld Fish Soc India 2001, 33(1), 25-31.

Ecological status and productivity potential of river Mahanadi between Durgapalli and Narsinghpur was studied in relation to various parameters. The sediment texture indicated very high percentage to sand and was poor in nutrient. The water phase showed rich concentration of dissolved oxygen, while the other parameters showed moderate to reasonably high values.

4 tables, 13 ref

023061   Pant G B (Indian Institute of Tropical Meteorology, , Pune-411008) : Long-term climate variability and change over monsoon Asia. J Indian Geophys Union 2003, 7(3), 125-34.

5 illus, 1 tables, 71 ref

023060   Nisar Shaikh;Yeragi S G (Zool dep, G M Momin women's Coll, Bhiwandi, Dist. Thane, Maharashtra) : Some physico-chemical aspects of Tansa river of Thane district Maharashtra. J Aquatic Biol 2004, 19(1), 99-102.

A number of physical and chemical parameters were studied as a part of river water monitoring programme. Tanasa River is the most important river of Thane district in Maharashtra. It originates from the foot of Thalghat and ultimately meets in Arabian Sea. It is at present a non-polluted river; hence, its water is mainly used for drinking, irrigation and other domestic purposes. A dam is built on Vaitarna through which the Greater Mumbai gets water supply.

1 table, 18 ref

023059   Niraj Kumar;Singh A P;Gupta S B;Mishra D C (National Geophysical Research Institute, , Uppal Road, Hyderabad-500007) : Gravity signature, crustal architecture and collision tectonics of the Eastern Ghats mobile belt. J Indian Geophys Union 2004, 8(2), 97-106.

The Middle-Late Proterozoic Eastern Ghats Mobile Belt (EGMB) exhibits a conspicuous paired gravity anomaly structure with a relative gravity high over the EGMB and low over the adjoining Archean cratons. 2D modelling across the EGMB, contrained by available seismic information, suggests an eastward dipping crustal column with a thick crust of about 38-40 km under the adjoining older cratons which warped up to 35 km under the younger EGMB. The oblique ridge like structure along with the deep seated intrusive such as anorthosites and carbonatites, and occurrences of ophiolite melange indicate an ancient collision zone along the eastern margin of the adjoining cratons. The westward verging structure together with the exposed charnokite and khondalite rocks along the EGMB may represent lower crustal rock upthrusted from the east to the west. Highly disturbed Middle-Late Proterozoic Purana sedimentary basins abutting the EGMB may represent the peripheral foreland basins over the eastward subducting adjoining Archaean cratons.

4 illus, 49 ref

023058   Nayar S;Gowda G;Lakshmipathi M T (College of Fisheries, , Mangalore) : Diel variation of biotic parameters in a tropical coastal lagoon on the South West coast of India. J Inld Fish Soc India 2001, 33(1), 32-7.

Diel variation in a coastal lagoon near Mangalore was studied during monsoon, postmonsoon and premonsoon. Chlorophyll-a was maximum at 1500hr with relatively higher values during post monsoon. Phaeopigment was also high at 1500h particularly during pre monsoon. Bacillariophyceae dominated the phytoplankton assemblages with higher counts during premonsoon. Primary productivity exhibit a similar trend as that of chlorophyll-a. Zooplankton biomass was observed to be generally high during early hours (0600 ^ 0900h) with higher values during premonsoon. the study points out light, salinity and temperature to be regulating the biotic fluxes in the environment.

6 illus, 1 table, 18 ref

023057   Nath D;Srivastava N P (CICFRI, , Barrackpore) : Physico-chemical characteristics of Narmada for the stretch Sandia to Mola in M.P. state in the context of construction of reservoirs on the river or its tributaries. J Inld Fish Soc India 2001, 33(1), 17-24.

Physico-chemical regime of Narmada between Sandia and Mola in M.P. State was studied at seven centres during 1996-1999. The physico-chemical parameters such as temperature, D.O., pH, total alkalinity, free Co₂, chloride, phosphate, nitrate, silicate, sp. conductivity, calcium and magnsium in general, indicated normal trends. However, forestation in the catchment areas might have determental effect on the ecology of the river as evident from low water depth, low flow rate, high silt deposition and dense growth of submerged vegetation. Though, the river was receiving industrial (S P M) and municipal (Hoshangabad) effluents, the damage was generally of low magnitude in view of its high self purifying capactiy.

3 tables, 6 ref

023056   Narayanan K (Dhruva, 5th Cross Street, , Trustpuram, Chennai-600024) : India's choice of an energy policy and its impact on future economic growth-discussed with special reference to fossil fuels. J Indian Geophys Union 2004, 8(2), 79-96.

Natural gas seems to be the only available alternative fuel for energy infrastructure growth. However, domestic reserves would seem to be inadequate to base any more thermal plants on gas. Unless India imports very large volumes of piped gas or LNG, this route is also not easily available. Regional arrangements outside the purview of global trading systems would be the only safe was for India to go for increased use of energy by the natural gas route.

14 tables

023055   Nagarnaik P B;Bhole A G;Natarajan G S (Laxminarayan Institute of Technology, , Nagpur) : Adsorption of Arsenic on flyash. Indian J envir Hlth 2003, 45(1), 1-4.

Studies on removal of AS(III) by adsorption on flyash and activated carbon powder have been carried out at room temperature (30±1°C). The adsorption isotherm of AS(III) on flyash and activated carbon powder was obtained in a batch reactor. Various parameters such as pH, initial concentration of absorbate and absorbent does were studied. The experimental adsorption data fitted reasonably well to the Langmuir and Freunlich isotherm for both the absorbents. Activated carbon has been observed to have greater adsoptive capacity than flyash.

6 illus, 1 table, 7 ref

023054   Mohan Kumar G;Sampath S;Jeena V S (Atmospheric Sciences Division, Centre for Earth Science Studies, PB7250, Akkulam, Thirvanathapuram-695031) : Continous measrement of ambient carbon monoxide at a tropical coastal station. J Indian Geophys Union 2004, 8(3), 205-10.

Carbon monoxide (CO) is toxic gas formed in all burning processes under insufficient oxygen conditions. Accmulation of CO in the atomosphere is of concern as its accumulation degrades the ambiet air quality. Measurements of ambinent CO was carried out uisng a standard CO Analyser (Monitor Europe Model 9830B) in Thiruvananthapuram, a tropical coastal station (8.5°N, 77.6°E). CO was measured from January till June 2003 only during the daytime and on a continuous mode from August 2003 onwards after using an uniterrupted power supply. The site of measurement is close to a water body (Akkulam Lake) adjoining the Arabian Sea. Preliminary results indicate that the ambient CO values are close to 100ppb and indicate agreement with the MOPITT satellite data for the surface. During this measurement in 2003, there were two local events associated with firewood burning in open areas. Enhanced CO values were noticed associated with the events and the dissipation of this enhancement with time was also see. The ambients levels of CO, its diurnal variations and its links with meterological parameters are presented and discussed.

4 illus 10 ref

023053   Melwanki M B;Seetharamappa J (Reseacher Scholar, Dep of Chemistry, Karnatak Univ, Dharwad-580003) : Spectrophotmetric studies on the investigation of chromium in environmental samples. Indian J envir Hlth 2003, 45(1), 25-8.

Isothpendylhydrochloride is proposed as a sensitive and selective reagent for the rapid spectrophotometric determination of chromium (VI). The reagent instantaneously gives a red coloured species on reaction with chromium (VI) in phosphoric acid medium which exhibits maximum absorbance at 510 nm with Sandell's sensitivity of 2.28 ng cm^-2. Beer's law is valid over the concentration range of 0.1-1.9 mg/l with an optimum concentration range of 0.2-1.7 mg/l. The method has been successfully applied to the analysis of chromium in environmental samples.

^iiaillus, 2 tables, 7 ref

023052   Meitei N S;Patil P M;Bhosle A B (Zool & Fishery Sci Dep, Sci Coll, Nanded -431 602) : Physico-chemical analysis of purna river for potability. J Aquatic Biol 2004, 19(1), 103-05.

Physico-chemical characteristics of Purna river water along a 3 km stretch were analyzed over a period of one year. The various parameters include pH, temperature, dissolved oxygen, total solids, total hardness and chloride. The parameters showed pollution trend were increasing due to discharge of sewage and anthropogenic activities. The dissolved oxygen content showed an inverse relationship with temperature. The total hardness and chloride were positively correlated. The water was found alkaline in nature.

8 ref

023051   Mahajan S R;Nandan S N (Botany Dep, Bhusawal Arts, Sci and P.O.Nahata Commerce Coll, Bhusawal Dist-Jalgaon) : Studies on euglenophycaean diversity in Velhala lake of Jalgaon, Maharashtra. J Aquatic Biol 2004, 19(1), 13-14.

265 algal taxa were recorded from three stations of Velhala lake situated on small tributary of river Tapti at 25°55' North Latitude and 75° 50' East Longitude. Out of these, 23 species belonging to 6 genera of euglenoids have been enlisted.

8 ref

023050   Jayaraju N (Dep of Geology, S.V. Univ, Tirupati-517502) : Control on formation an distribution of heavy minterals along southern tip of India. J Indian Geophys Union 2004, 8(3), 191-4.

An attempt has been study the southern most tip of India extending on either limbs to a length of 100 kms for varied compositional suite of heavy minerals. A total of 25 samples have been collected to study the control and distributional pattern. The abundant heavies are ilmenite, monazite, garnet, zircon rutile, tourmaline, limonite, Kyanite, sphene and hornblende. The high concentrations of monazite an dilmenite are more in Kovalam area (min 12.3% and max. 44.1%) and decreases toward Kannyakumari (Cape-Camorin). The black sand concentration increase wth smaller amounts of garnet giving red hue to the sediment. The trasformation of black sand to red is not rapid but gradual wtih a transitional stage of almost equal proportions of black (50% and red (50%) sands. This may be due to the distinegration and decomposition of host rock made up of relatively resistant garnet minerals in the interland/floor of the ocean. The relatively resistant heavy minerals might have been detached from the source rock and brought on the shore forming patches and pockets by winnowing and turbulent actions of waves. In some samples, black hue may be due to the predominance of titanium minerals but not magnetite, which is in meagre amounts. In the study area each species is characterised by the predominance of one constituents which is also emphasised by colour variation. Further, climatic changes play a pivotal role in the formation and distributin of heavy mineral suits, indriectly inflecting the impact of climate in the sedimentary environment. The economically viable heavy mineral deposits along the study area are governed by the presence of host rock in the close proximity, existing drainage pattern, topography, climate and coastal processes. Heavy minerals associated with sediments indicate that they are derived from a metamorphic terrain dominated by Precambrian gneiss, shist and ferruginous quartzite of Indian peninsular shield

1 illus, 1 table, 13 ref

023049   Israil M;Gupta P K;Tyagi D K (Dep of Earth Sciences, Indian Institute of Technology Roorkee, Roorkee-247667) : Determining sharp layer boundaries from straghtforward inversion of resistivity sounding data. J Indian Geophys Union 2004, 8(2), 125-33.

The main purpose of this paper is to develop methodology to determine geologically inspired layer boundaries from the inverse model obtained using inversion techniques like straghtforward inversion scheme (SIS) and Occum's whrein sharp boundaries are missing. These techniques essentially solve for an over prarmeterized model and through regularized minimum norm solution a smooth model achieved. Two different methodologies to identify sharp boundaries of the model inherent in the smooth model have been presented. In the first, the solution of linear inverse probelm is improved iteratively through weighted minimum norm inverse, the weight being taken from the current solution. The technique is referred as Iterative Sraightforward scheme (ISIS). The second method is an analytical, based on the application of smoothing filter and referred as Edge-Preserving smoothing (EPS). The implementation of these methodologies are demonstrated by different test models from the published literature and over a field data set. These methodologies also reduced the conspicuous oscillations in the smooth solutins caused due to converstin of sharp boundaries to the smooth one.

6 illus, 31 ref

023048   Himabindu D;Ramadass G (Centre of Exploration Geophysics, Osmania Univ, Hyderabad-500007) : Estimation of crustal thickness from power spectra of regional bouguer gravity: Jadcharla-vaso transect. J Indian Geophys Union 2004, 8(2), 173-8.

A procedure for rapid estimation of average crustal configuration from spectral analysis using an established relation has been described. From the regional Bouguer gravity profile along the 600 km Jadcharla-Vasco transect in the Dharwar craton, four deep-seated faults were inferred from the undulations in the Moho, which formed the basis for tectonic classification of the craton into the western, intervening and eastern blocks. While the average crustal thickness obtained for the western block was 39 km, for the eastern block it was 37 km. The two blocks are separated by an upthrust intervening block where the depth to the Moho at the Chitradurga thrust that occurs roughly in the middle of the block, was found to be 34.5 km.

2 illus, 21 ref

023047   Gowd T N (National Geophysical Research Institute, , Hyderabad-500007) : Stable continental region earthquakes due to pressure weakening of existing faults. J Indian Geophys Union 2004, 8(3), 195-8.

Stress conditions for the reactivation of existing thrust faults to rupture have been analytically investigated. The results indicate that the steeply dipping faults at Latur (θr=45°) and at Bhuj (θr=46°) and high angle reverse fault at Jabalpur (θr=67°) cannot be reactivated to rupture due to tectonic stress (σ₁ accumulation alone. Further, the results show that the steeply dipping thrust faults at Latur and Bhuj and the high angle rupture fault at Jabalpur can be reactivated to rupture by pressure-weakning due to near-lithostatic fluid pressures and Supra-lithostatic fluid pressures respectively caused by the fault valve behaviour. Deadliest Latur earthquake of 1993, the devastating Bhuj earthquake of 2001 and the Jabalpur earthquake of 1997 were caused due to pressure weakening of thrust faults due to near-lithostatic fluid pressures and supra lithostatic fluid pressures respectively, caused by fault valve mechanism because of which deposition of valuable ores in the deeper parts of these fault, might be taking place during each earthquake cycle.

9 ref

023046   Deo A A;Ganer D W;Salvekar P S (Indian Institute of Tropical Meteorology, , Pune-411008) : Behaviour of the upper ocean in response to an idealized symmetric and asymmetric Indian Ocean cyclone in opposite hemisphere. J Indian Geophys Union 2004, 8(3), 211-22.

The effect of moving symmetric and asymmetric tropical cyclone in the northern and southern Indian Ocean, on the oceanic upper layer is studied, using a simple reduced gravity ocean model. Different tracks in the norther Indian Ocean and their mirror image in southern hemisphere are considered on the basis of existence of various such systems. The model temperature and mixed layer depth are examined during the passage of cyclone along these tracks. The model fields show the bias to the right (left) of the storm track in the northern (southern) hemisphere for the symmetric cyclone case. The asymmetric winds to the left and right of the each track considered are used to force the model in another experiments. The model output is found to be enhanced with the right asymmetric case as compared to the left asymmetric case.

7 illus, 1 table, 12 ref

023045   De U S;Rao G S P (Visiting Faculty, Pune Univ, Pune) : Urban climate trends-The Indian scenario. J Indian Geophys Union 2004, 8(3), 199-203.

The growth of population in India during the past few decades has been stupendous. Some of the biggest megalopolis of the world are located in India with population in excess of 10 million. The study focuses on the trends in the climatic parameters in major cities of India, whiuch have population in excessess of 1 million (10 lakhs). The 'Urban heat island" is well known. Apart from this, long term trends in rainfall, temperature and aerosols have also been noted (Pillai 1999). Total suspended particles (TSP) in major Indian cities vary from 200-500 mg/m³ and these are generally basic (soil origin) in nature. However, the major urban airports are faced with increased load of aerosols as reflected in the long-term deterioration of visibility, especially during winter months (De & Dandekar 2001). Studies in long-term trends of rainfall in several cities such as New Delhi, Kolkata Mumbai and Chennai show significant increasing trends in annual and monsoon rains. These may be due to changes in the meso scale circulations near the cities as reported in studies done else where such as project Metro Max in USA. Changes in frequencies of occurrence of warmer day (Maximum temperature above certain threshold) and colder days (Minimum temperature below certain threshold) have also typical signatures of urbanization (Rao, Jaswal & De 2000). With a shife in demography towards urban areas deterioration of air quality formation of `heat islands' and poorly constructed dwelling units make over urban centers to weather hazards (De & Dandekar 2001). There is an urgent need of urban growth planning for to overcomeing these problems.

2 illus, 2 tables, 9 ref

023044   Cynthia Johnson M E;Kauser R (Limnological Lab, Botany Dep, Osmania Univ college of Women, Koti, Hyderabad-500 195) : Chemical and microbial quality of different types of drinking water of Hyderabad, Hi-Tech city, A.P., India. J Aquatic Biol 2004, 19(1), 93-7.

An examination of certain chemical and microbial parameters of various drinking water samples of Hyderabad Hi-tech city was carried out to assess their hygienic quality and impact in human health. Three different types of drinking water sources were identified i.e. well, bore well and piped municipal water supply. It was observed that chemical components like HCO₃, Cl, NO₃, and PO₄ had a direct effect on the bacterial and fungal population of the water samples. Consuming well water containing more number of bacteria led to dysentery and diarrhoea, while bore well water having more fungal members led to throat, ear and scalp infections.

2 tables, 18 ref

023043   Allam S M;Ezzat A A;El-Maghraby A M;Solimen I A;Wadie W F (National Inst of Oceanography of Fisheries, , Alexandria, Egypt) : Systematic study of the genus Trachurus in the South-Eastern part of mediterranean sea. J Inld Fish Soc India 2001, 33(1), 54-8.

Systematic study of the Genus Trachurus is described from the Egyptian Mediterranean waters. This will not only in proper identification of the species but also in scientific management of fisheries.

12 ref

022237   Ugarkar A G (Department of Geology, Karnatak University, Dharwad 580 003) : Characteristics of banded iron formation hosted gold mineralisation in the archaean schist belts of Karnataka craton. Indian Mineralogist 2002, 36(1), 14-25.

Banded iron formations (BlFs) are the characteristics components of the Archaean schist belts of Karnataka craton and at several places they are found to be gold bearing. Volcanic association is generally common in respect of these BlFs and they are more akin to Algoma type. Based on the facies of host BlF, gold mineralisation of Karnataka craton can be classified into two types. First type is hosted by sulphide facies BlF and second type is hosted by oxide facies BlF. Both share certain similarities in the mineralisation characteristics. These BlFs and the associated lithologies are co-folded and metamorphosed under greenschist to amphibolite facies. Gold occurs in native form, intimately assciated with Fe-sulphides like pyrite, pyrrhotite, arsenopyrite and chalcopyrite. Alternations around quartz veinlets are characterized by abundant chlorite, sericite, actinolite and carbonates. Sulphidation reaction <75> to partial replacement of magnetite by pyrite and pyrrhotite is noticed in majority of places.

1 table, 48 ref

022236   Tomar A S;Ranade D H (All-India Co-ordinated Res Project on Dryland Agric, Coll of Agric, Jawaharlal Nehru Krishi Vishwa Vidyalaya, Indore-452 00, ) : Modelling cumulative rainfall by growth models for rainfed Indore region of Madhya Pradesh. Indian J agric Sci 2004, 74(2), 108-09.

2 tables, 4 ref

022235   Subba Rao D V (Department of Mineral Beneficiation, S D S Autonomous College, Shreeramnagar 535 101) : Evaluation of washability characteristics of Talcher coal, Orissa. Indian Mineralogist 2002, 36(1), 26-33.

Increase in the production of non-coking coal in India and the deterioration of the quality of coal supplies necessiates the beneficiation of non-coking coal in order to use them for several purposes in general and for metallurgical purposes in particular where the coal with ash content as low as 15% is required. An attempt is made to evaluate the washability characteristics of thermal coal from Talcher, Orissa at different size fractions through various parameters viz., Characteristic Curve, Near Gravity Material, Overall Washability Index, Partial Washability Index. Index of Washability. Degree of Washability and Washability Number. The coal sample used for study is of 36.28% ash. The raw coal sample is crushed to -38 mm, 4 +2 mm and - 2 + 0.5 mm are prepared and float and sink tests are conducted on all five fractions. This study has revealed that the coal is having difficult washability characteristics and washability at finer sizes is better.

7 illus, 4 tables, 4 ref

022234   Sikdrar P K;Chakraborty S;Paul P K; Chakraborty M (Dep of Environment Management, Indian Institute of Social Welfare and Business Management, Kolkata) : A GIS approach to evaluate the impact of integrated wasteland development programme of Ghogha, Bhavnagar district, Gujarat. Indian J Earth Sci 2002, 29(1-4), 27-38.

The study of about 61 sq km comprising nine villages is located in Ghogha block, Bhavnagar district of Gujarat. The area suffers from acute shortage of water and ingression of saline water. This has resulted in land degradation, formation of wasteland and consequent shrinking of agricultural land. These probelms called for an integrated wasteland development programme (IWDP), which started in January 1999. Impact of development programmes on natural resources and local community has been evaluated. Analysis reveals that water related problems are far less in project villages compared to villages where IWDP has not been initiated. Multi-Criteria evaluation (MCE) using MAPINFO indicates that in the project villages there have been significant beneficial impact in the form of rise in ground water level, increase in crop and milk yield and decrease in population migration. The most beneficial villages are Vavdi and Oderka and the least impected villages are Rajapara and Chhaya. To increase the beneficial impact still further appropriate measures have been suggested. It is envisaged that if these measures are implemented then there will be a distinct improvement in the quality of life in Ghogha.

6 illus, 13 tables, 5 ref

022233   Sharma V;Shah D (Central Ground Water Board, , Northern Region, Lucknow) : Safe distance for heavy deep tube wells tapping upper tertiary sandstones of Tripura State. Indian J Earth Sci 2002, 29(1-4), 19-26.

A potential system made up of Upper Tertiary Tipam Sandstone exists in the state of Tripura between 50 m 250 m below ground level. Ground water caters about 90% of the total domestic supply of the state and also pays a crtical role to meet the irrigation demand. Heavy-duty deep well, having a depth range of 80-200 m are becoming popular, dependable and cost effective structures for domestic as well as irrigation supply. Pumping test results indicate that the tube wells ranging in depth between 132 and 231 m tap confined to semi confined aquifer with transmissivity ranging from 90.3 to 1582 m²/day. To achieve optimum density to deep tube well, safe distance for tube wells used for irrigation purpose has been worked out to be 2 km for low transmissivity aquifers (less than 700 m²/day) and at least 3 km for high transmissivity aquifers. For the deep tube wells used for drinking purpose the safe distance can be kept as 1.5 km for low transmissivity area and 2.5 m for higher transmissivity areas.

2 illus, 5 tables, 8 ref

022232   Rudramuniyappa M V;Ravi Raju (Department of Mineral Processing, Gulbarga University P G Centre, Krishnadevaraya Nagar, Sandur 583 119) : Beneficiation of ferruginous chromite ores of Sukinda area, Orissa. Indian Mineralogist 2002, 36(1), 71-5.

Sukinda-Nausahi ultramafic belt of Orissa, represents about 98% of the Indian chromite ore reserves. Chromite is mainly used in metallurgical refractory and chemical industries. The chromite deposits of Sukinda ultramafic belt is located in E-W trending valley flanked on the north by Daiteri hill ranges and Mahagiri range on the south. The ultramafic body consists mainly of magnesite rich dunite and peridotite with the chromite bands. Low grade ferruginous chromite ore analysing Cr₂O₃-24.12% and Fe-21.95 has been subjected to Jigging studies at two stages. One, without magnetic separation of the feed and secondly the feed was subjected to magnetic separation. The non magnetic product was used for Jigging studies. The results obtained have been discussed. Three experiments in each case were conducted by varying the flow rate of water i.e., 4, 6 and; 8 lit/min at 3/16" stroke length and water flow rate of 8 lit / min. the Cr₂O₃ concentrate obtained was 42.5% for the feed without magnetic separation. At the same condition the experiments carried out for non magnetic product has resulted in little improvement in the Cr₂O₃ content with Cr:Fe ratio 1.74. The concentrate obtained with Cr:Fe ratio less than 1.4 are not acceptable in metallurgical plants. The results obtained have shown Cr: Fe ratio more than 1.4 and the low grade Chromite ores of Sukinda area can be used effectively after beneficiation in different industries.

4 tables, 4 ref

022231   Ray A;Mondal R P (Dep of Geology, Presidency College, Kolkata) : Petrological account of nephline syenites and associated rocks, around Kankarkiari, Purulia District, West Bengal. Indian J Earth Sci 2002, 29(1-4), 1-11.

Nepheline syenites and associated magmatic rocks (namely syentsies, alkali gabbrro etc.) occurring around Kankarkiari, Purulia district, are disposed in east west direction along the strike of the regional foliation of high grade metamorphic country rocks. The magmatic suite is composed dominantly of nepheline syenites with little amount of alkaline basic rocks. Coarse, mafic dominated alkaline basic rocks occur as inclusion within felsic, fine-grained nepheline syenites. Texturally nepheline syenites can be classified as coarse, well foliated and fine, crudely foliated ones, the latter being intrusive into the earlier. Mineral composition indicated variuos mineralogical types of nepheline syenites such as-biotite-nepheline syenite, perthite-nepheline syenite, amphibole-nepheline syenite etc. Major and few trace element data indicate significant variation indicating differentiation within the magmatic suite. Such differentiation is possibly be the result of fractination of early formed minerals like pyroxene and calcic plagioclase from an alkaline basic melt. The residual melt, thus produced, might have given rise to the nepheline syenites of the present area.

8 illus, 2 tables, 32 ref

022230   Ravi B P;Rao B S (Regional Ore Dressing Laboratory, Indian Bureau of Mines, Bangalore 560 022) : Small capacity mineral processing plants of peninsular India. Indian Mineralogist 2002, 36(1), 5-13.

The small capacity mineral procesing plants are defined as the plants having a maximum annual ore treatment capacity of 2 lakh tons. The advantages of small plants and their contribution to mineral industry are mentioned. The small mineral processing plants of Peninsular India are enlisted. Some of the characteristics of small plants are outlined. The problems faced by small plants in general, the probable reasons for poor performance and some general suggestions to improve the performance are mentioned. A few Indian case studies are also discussed. Efforts for concerted corrective action by the government agencies, management of small plant, suppliers, global leaders and consumers are stressed to minimize the wastage of small natural resources and ecological damage.

1 table, 2 ref

022229   Rajashekar Reddy K;Puranik S C;Wodeyar J K (Department of Studies in Geology, Karnatak University, Dharwad) : Recovery and settling rate of - 10m clay fractions from precambrian clay deposits of Majjur area, Gadag Schist Belt, Karnataka. Indian Mineralogist 2002, 36(1), 1-4.

The recovery and settling rate of -10 m clay fractions from Majjur area, Gadag schist belt, Karnataka are studied. The - 10 m clay fractions are recovered after degritting of raw clays. The deflocculation study in performed with degritted clays using gravity sedimentation technique to know the efficiency of dispersants and flocculants on yield of - 10 m clay fractions. The dispersants used are sodium phosphate, sodium hexametaphosphate and sodium pyrophosphate. The dispersants are used individually and as well as in combination. Alum and line + starch are used as flocculants. The experiments reveal that the rate of setting is more with high concentration of flocculants and in the first minute of settling. The rate of settling gradually decreases and is uniform after sixth minute for next 20 minutes or till the settling is complete. The recovery percentage of - 10 m clay is 41 % when sodium carbonate + sodium (1:1) is used as dispersant and alum as flocculant.

1 illus, 1 table, 3 ref

022228   Paul A;Singh V N (Dep of Geology, Kumanon Univ, Nainital 263 002) : Fault slip distribution models from aftershock data a study using waveform modelling. Indian J Earth Sci 2002, 29(1-4), 44-52.

Two models of slip distribution on the fault plane obtained from the avilable data on aftershock activity following the occurrence of Uttarkashi earthquake of October 19, 1991 have been determined. The first of these models based on aftershocks with local depth less than 5 km and the second, on aftershocks deeper than 5 km. The two slip models have been used to generate synthetic accelerograms. The Fourier phase spectra of synthetic accelerograms have been compared with those of observed ones recorded at Uttarkashi, Koteshwar and Ghansyali. The comparison indicate that the model obtained by shallow aftershocks yield better results.

8 illus, 2 tables, 14 ref

022227   Naganoor P C;Appanagoudar (Department of Earth Sciences, G U P G Centre, Nandihalli-Sandur - 583 119) : Production of ferro-titanium from the titaniferous magnetite deposits of Madanagere-morahalli area, North Kanara district, Karnataka. Indian Mineralogist 2002, 36(1), 34-41.

Vanadium bearing titaniferous-magnetite samples from Madanagere-Morahalli area, North Kanara Dist., Karnataka, India, analysing TiO₂ - 9.3%, V₂O₅ - 1.11 %, FeO - 9.79 %, Fe₂O₃ - 70.64 % %, SiO₂ - 1.68%, Al₂O₃ - 3.93 %, MnO₂ - 0.4 % have been initially subjected to low intensity wet magnetic separation, producing 55.9 wt % magnetic and 44.1 wt % non-magnetic fractions. The non-magnetic fraction containing, Tio₂ - 17.42 %, V₂O₅ - 0.46 %, FeO - 11.50 %, Fe₂O₃ - 54.59 %, SiO₂ - 3.42 % and MnO₂- 0.68 % was subjected to open - aluminothermic reduction process for the production of low-carbon ferrotitanium. Number of experiments have been carried out by varying the process variables to establish the following optimum conditions:- 1. Average size of reductant (Al-powder) - 0.104 mm 2. Amount of reductant-Stoichiometric amount of aluminium powder needed for reduction. 3. Preheating temperature of the charge mixture - 500° C. 4. Amount of flux - Lime in an amount of 25 % of theoretical aluminium. Under these conditions it is possible to produce ferrotitanium analysing - Ti - 11.05 %, Al - 6.59 %, Si - 2.17 %, Mn - 0.55 %, V - 0.33 %. C - 0.11 % and Fe - 70.19 % with a maximum of 82.13 alloy yield and 55.36 % titanium recovery. The experimental details and results obtained are described and discused.

5 tables, 11 ref

022226   Krishna Prasad V;Yogesh Kant;Badrinath V S (National Remote Sensing Agency, Dept. of Space, Govt. of India, Balangar, Hyderabad-500 037) : Studies on DMSP-OLS night time satellite data over Indian cities. Indian J Earth Sci 2002, 29(1-4), 39-43.

The unique capability of Defence Meteorological Satellite Prograe Operational Line Scan System (DMSP OLS) data to detect Visible and Near Infra-Red (VNIR) sources during the night time, has been used for detection of lights from cities, towns, industrial sites, gas flares and ephemeral events such as fires and lightning illuminated clouds in other regions of the world. Such studies in the Indian regiona using DMSP-OLS data are lacking. An attempt has been made to relate stable lights from cities monitored through DMSP-OLS night time data to the population growth over a time period of about ten years from 1987 to 1998. Results suggest that, although the population intensity in the cities is related strong with city lights, pupulation growth trends in some cities such as Bangalore and Hyderabad, do not show regular trend. Various trends in population intensity with that of city lights from different cities of India has been analysed.

3 illus, 3 tables, 5 ref

022225   Kori S A;Reddy P L N;Bhat K L (Dept of Mech Engg Basaveshwar Engineering College, , Bagalkot 587 102) : Effect of process parameters for the extraction of zinc from sphalerite concentrates. Indian Mineralogist 2002, 36(1), 42-50.

An attempt has been made to recover zinc from sphalerite concentrates by anodic electroleaching in sulphuric acid. The effects of particle size, temperature, time, acid concentration, stirring and additives on the extraction of zinc were studied. The results show that, in the sulphuric acid electrolyte, the electroleaching of sphalerite is inhibited after about 40% zinc extraction. Over 90% zinc extraction has been achieved with elemental sulphur as by products when sphalerite was leached in the presence of sodium chloride and potassium bromide. The dissolution of zinc was found to be increased with increase in acid concentration, temperature, time stirring and with decrease in particle size. A so reports on the SEM studies on sphalerite concentrates extracted zinc and by-product of elemental sulphur.

3 illus, 3 tables, 7 ref

022224   Jamal A;Siddarth S;Singh R P;Jain A K (Department of Mining Engineering, Institute of Technology, Banaras Hindu University, Varanasi-221 005) : Use of geological parameters in pre-mining prediction of ACID drainage in lead-zinc deposits, Bilwara district, Rajasthan. Indian Mineralogist 2002, 36(1), 51-60.

Among the various water resource management problems caused by mining industry, acid mine drainage (AMD), is one of the most serious water pollution problems in many metal sulfide mines in the country. IN lead-zinc mines, sulfide minerals particularly pyrite is responsible for acid mine drainage. The occurence of pyrite along with Galena and Sphalerite is most common and it reacts with water (surface and ground water) in presence of oxygen to form sulfuric acid and make the mine water acidic. Disposal of acid water from mines not only corrodes the pipes and pumps, but also degrades the quality of receiving stream. The pre-mining prediction of water effluent in Pb-Zn mine, therefore, is the need of hour to formulate the acid water management even at exploration or planning stage. Geochemical parameters like `acid production' and `acid neutralization' potentials are the most effective tools for prediction of quality of water in general and acid mine drainage in particular. In any mine, the acid production potential (APP) and acid neutralization potential should be approximately equal upto pit depth for neutral water of sump i.e. APP = ANP. If APP is significantly more than ANP, the mine may suffer with acid water core samples of rocks containing lead-zinc near exploration site in Bhilwara district of Rajasthan were collected for weathering experiment. A simulated weathering procedure was followed to know the rock-water interaction behaviour. The result of this study confirmed that the ores and associated rocks in the area have been playing active role in the degradation of quality of natural water.

5 illus, 4 tables, 7 ref

022223   Ghosh N (Dep of Geological Sciences, Jadavpur Univ, Kolkata-700032) : An experimental study on composite boundinage structures. Indian J Earth Sci 2002, 29(1-4), 12-18.

Development of composite boundinage structure in rocks takes place with very complex rheological properties. Simple qualitative experiments with soft materials were carried out to simulate the development of composite boudins in multilayer rocks. The experiments indicate that the relative time of formation of boudins in the inner layers or in the multilayer as whole depends on the relative competence contrasts of the associated layers. The formation of the extension fracture or shear fracture boudins depends on the relative thickness of the inner layers within the multilayer.

5 illus, 5 ref

022222   Desai H Y;Prabhakar B C (Zuari Cement, , Krishna Nagar, Yerraguntla, Cuddapah) : Possibilities of utilising limeslag and limedust in manufacturing cement - a study from Bhima basin, Karnataka. Indian Mineralogist 2002, 36(1), 66-70.

Limestone deposits of Bhima basin in Northern Karnataka are well known for their economic value both as decorative stones and as raw material for manufacturing cement. Five major and 15 mini cement plants and about 300 stone polishing and slab quarries are operating in this region. Vast amount of stone chips, dust and sludge is generated during various process of cement manufacturing, especially at crusing sites. It is estimated that an average of 20 tonnes/day of dust crushed chips are accumulated from a 1200 tph crusher. Sludge former due to water action is also a major disposal problem. The waste thus generated in quarrying/polishing units and cement industries are causing environmental hazards, in the form of land degradation, dust pollution and damage to aesthetic value of the sites. To overcome this situation and in view of the effective utilization of the available mineral reserves, reusing of the said waste in manufacturing cement is worth venturing. A mini cement plant of 300 tpd (or reusing of these wastes by major cement industries) in this region is commercially viable by utilizing the wastes.

1 table, 8 ref

022221   Chandra S (Baroaritala, Katawa - 713130, , ) : Gondwana revisited. Indian J Earth Sci 2002, 29(1-4), 53-67.

This revisit of Gondwana is based primarily on a bed - by - bed lithogenetic documentatin of several scores of thousands of metres of cores drilled in the coalfields. The historical comtext emphasises the desirability of building up independently a continuous stratigraphic column in the Godavari valley as the future standard for the whole of Gondwana. `Mode of Formation' at different scales is accorded primacy in assessing attributes like colour, pebbles and shells. It is felt that the half- way house in the Gondwana stratigraphy now makes the paleogeographic mobilist reconstructions rather premature.

2 illus, 3 tables, 55 ref

022220   Ananda T C;Shiva Kumar B S;Mariappa M C (Department of Geology, Bangalore University, Jnanabharathi, Bangalore 560 056) : Structural controls for gold mineralisation in sulphide facies of banded iron formations in central parts of Chitradurga Schist Belt, Southern Karnataka. Indian Mineralogist 2002, 36(1), 61-5.

Gold is being produced in India mainly from the lode deposits of green stone belts of Hutti, Kolar and Ramagiri, With the gold reserves depleting, there is an urgent need to search for new deposits not only in volcanic rocks but also in other different lithologies like banded iron formation (BIF), Laterites, Conglomerates, Graywaske, etc. The central parts of Chitradurga Schist belt (CSB) is one such area, which fulfils the lithotectonic condition favourable for gold mineralisation in BIf. In view of its economic potential, this belt has been selected for detailed structural geochemical sutudies. Chikkasiddavanahalli-Kennedlu-Kurubara mardikere (C S Halli-Kennedlu - K M Kere) blocks from part of central parts of (CSB) belonging to Dharwar Super Group of middle to upper Archean age. Geology of the area comprises of metavolcanics, metasediments, BlFs, basic and younger intrusives, conglomerates, etc. The BlFs in the study area are prominent marker lithounits exposed as linear ridges with N-S to Ne-SW disposition. Generally BlFs show fine lamination, which vary in thickness from 1 mm to few cm with micro, meso, and macro banding of alternate chert and iron minerals. All the lithounits in these blocks occur in the eastern limb of the major Chitradurga are and has general attitude of NNW trend with westerly dipping. ALl BlFs in these blocks are structurally controlled by three phases of deformation. F₂-folds of all BlFs show dextral shifting with SOuth-Easterly plugging (52° towards 165). Evidences of auriferous and basemetal mineralisation in different bands of BIF are observed. Rich mineralisation can be inferred ony at hinge portions of F₂ fold due to sulphidisation of pyrrhotite, arenopyrite, pyrite, etc.

2 illus, 5 ref

000108   Wang L;Zhang S;Liu Z;Li H;Xu A (Mar Biol Dep, Ocean Univ of China, Qingdao 266 003, P R China) : Cloning, characterization and expression of amphicypa, a homologue of eukaryotic cyclophilin a gene from amphioxus Branchiostoma belcheri tsingtauense. Curr Sci 2004, 86(7), 1007-11.

Cloning and characterization of a full-length amphioxus cyclophilin cDNA has been reported. The cDNA consisted of 1358 bp with a 495-bp open reading framd (ORF) corresponding to a deduced protein of 164 amino acids, with a calculated molecular mass of 17.3 kDa. It possesses the signature sequence of Cyclophilins (Cyps) in the PROSITE library, and all the conserved 13 amino acids, including the crucial tryptophan (W) residue (position 121) that are predicted to be involved in PPIase activity and CsA binding. It has neither N-terminal extension sequence nor C-terminal extension sequence. These indicate that the cDNA encodes a homologue of eukaryotic cyclophilin A, designated As AmphiCypA. Phylogenetic analysis shows that AmphiCypA is intermediate between sea urchin Cyp and zebrafish Cyp, clustering together with zebrafish Cyp. This agrees with the notion that amphioxus represents a basal lineage of chordates in phylogeny. Northern blot analysis revealed that amphiCypA is expressed in all the tissues examined, but its expression is apparently elevated in fully-grown ovaries. It is suggested that elevated expression of AmphiCypa in fully-grown ovaries could be due to a role for this protein in oogenesis or it may be involved in early development.

5 illus, 34 ref

000107   Vimal Singh;Tandon S K (Geology Dep, University of Delhi, Delhi-110 007) : Facies association and sedimentary petrological characteristics of Lameta sequences of the Dongargaon area Central India. J Geol Soc India 2004, 63(1), 39-50.

The Lameta Formation of the Dongargaon area is associated with the locally occurring basal Deccan lava flows. These sequences have been studied for their facies associations, petrographic, and diagenetic attributes in four localities: Dongargaon hill, Dongargaon nala, Dhamni/Pavna and Bujoli/Sagra. Four facies associations -lacustrine-A,lacustrine-B, overbank with minor sheetwash deposits and (d) minor channels have been recognized by previous workers as well as in this study. An upsection shallowing trend is inferred. Petrographic studies resulted in the identification of two types of sandstones in the minor channel facies - one composed largely of calcrete grains and the other composed of quartzose grains. Diagenetic structures and fabrics of significance include septarian concretions and radiaxial fibrous calcite; and pedodiagenetic structures include mainly calcrete nodules and rhizocretions. The septarian concretions show a bimineralic character with a dolomicrite groundmass and a coarse crystalline spar filling up the cracks. Stable isotope composition of the calcrete nodules suggests a possible dual origin i.e., phreatic-pedogenic. Marl, calcareous siltstone and ostracods of the lacustrine facies range in values from -2.9>F128>% to -6.4% for δ¹³C and -2.7% to -5.9%o for δ¹⁸O, and suggest marked fluctuations in the lake's hydrological regime. Facies analysis, petrographic studies and stable isotope compositional data of selected carbonate facies and fabrics suggests that the Lameta Formation of the Dongargaon area is dominated by overbank and shallow lake environments. This contrasts with the dominance of palustrine and pond facies described previously from the Lameta Formation of the type locality of Jabalpur in Central India.

5 illus, 2 tables, 18 ref

000106   Subbaraman J V (1126, Geetha Road, Robertsonpet, KGF-563 122) : Factors of gold concentration in Champion Lode, Kolar Gold fields. J Geol Soc India 2004, 63(1), 114-16.

000105   Srinivasa Sarma D;Sawkar R H;Charan S N;Subba D V;Naqvi S M (National Geophysical Research Institute, , Uppal Road, Hyderabad-500007) : Chemical composition of tourmaline in metarhyolite near Majjur, gadag schist belt, Karnataka. J Geol Soc India 2004, 63(2), 217-21.

Tourmaline mineralisation is associated with fine to medium grained schistose metarhyolite near Mijjur within the Gadag schist belt, which is well knwon for hosting lode type of gold mineralisation largely in metavolcanic rocks. Tourmalines of prismatic habit oriented parallel to the schistosity and as basal sections developed prependicular to the schistosity are observed. Microprobe analysis of these tourmalines repoted here for the first time shows that they represent the end member compostions of Schrol-Dravite solid solution series. No distinct chemical or optical zoning is observed in either type of these tourmalines. These tourmalines are present in the outer frings of the laterations zone developed around the gold mineralized zones in associated rocks. An attempt is made here to relate the chemical compositions of the tourmalines, vis-a-vis their occurrence in the alteration zones and the nature of boron metasomatism.

^ssc3 illus, 1 table, 10 ref

000104   Sridhar M;Chowdhary V S;Nayak S S;Augustine P F (NO, Geological Survey of India, Hyderabad-560 068) : Short communication Discovery of kimberlite pipes in Gadwal area, Mahbubnagar district, Andhra Pradesh. J Geol Soc India 2004, 63(1), 95-9.

Three kimberlite pipes are reported from Siddanpalli village in Gadwal area, Mahbubnagar district, Andhra Pradesh, bringing to light a new kimberlite cluster. Significance of the find lies in the fact that these kimberlite pipes are located in the Krishna river basin well known for its alluvial diamond mining activity since historic times. These pipes are being studied for their diamond potential.

3 illus, 2 tables, 6 ref

000103   Sridhar A R;Tewari H C;Vijaya Rao (National Geophysical Research Institute, , Hyderabad-500007) : Upper crustal features as seen from near vertical and wide angle reflections along thuadhara-sindad DSS profile in Central India. J Geol Soc India 2004, 63(2), 204-16.

Trace normalized record sections of single fold seismic data, in Central India showed several reflections of large amplitude at upper crustal depth. Sythetic seismogram modeling of these reflections, reveal that they have originated from a combination of several alternating high low veocity layers. On a comparison of this model with other models available worldwide, it is felt that while some of these layers may be associated with the presence of fluids, the majority should be due to lateral variations in the near surface structures. However, the first arrival refraction and wide-angle reflection data do not show a similar structure even though a promient upper crustal low velocity layer could be identified.

8 illus, tables, 38 ref

000102   Singh U K;Singh R P (Civil Engineering Dep, Indian Institute of Technology, Kanpur-209 016) : Qualitative study of coast effect on MV and MT measuements in western coast of India. J Geol Soc India 2004, 63(1), 88-94.

Magneto-variational (MV) and Magnetotelluric methods (MT) use natural geomagnetic field which have been found to be affected by the ocean worldwide. During last decade, MV and MT studies have been carried out in the western part of India in the present paper. Two dimensional modelling has been carried out to investigate the coast effect on MV and MT data observed near the coast. Varying coastal and continental layer parameters of the western part of the Deccan trap region have been taken to examine the coast effect. The MV and MT data are found to be affected by the coast up to 300 km.

5 illus, 24 ref

000101   Simon A;Mohankumar K (Dep of Atmospheric Sciences, Cochin Univ of Science and Technology, Fine Arts Avenue, Cochin-682016) : Spatial variability and rainfall characterstics of Kerala. Proc Indian Acad Sci-Earth Planet Sci 2004, 113(2), 211-21.

Geographical regions of covariability in precipitation over the Keral state are exposed using factor analysis. The results suggest that Kerala can be divided into three unique rainfall regions, each region having a similar covariance structure of annual rainfall. Stations north of 10°N (north Kerala) fall into one group and they receive more rainfall than stations south of 10°N (south Kerala). Group I stations receive more than 65% of the annula rainfall during the south-west monsoon period, whereas stations falling in Group II receive 25-30% of annual rainfall duirng the pre-monsoon and the north-east monsoon periods. The meteorology of Kerala is profoundly influenced by its orographical features, however it is difficult to make out a direct relationship between elevation and rainfall. Local features of the state as reflected in the rainfall distribution are also clearly brought out by the study.

5 illus, 5 tables, 9 ref

000100   Sharma M D (Dep of Mathematics, Kurukshetra Univ, Kurukshetra) : Strains of scattering of near-field of a point source. Proc Indian Acad Sci-Earth Planet Sci 2004, 113(2), 247-57.

Three mensional scattering of near-field is studied for dilatation and rotation in the time domain. The perturbation method is applied to solve the equation of motion for the first order scattering from a weak inhomogneity in an otherwise homgeneous medium. The inhomogeneity is assumed close enough to the point source so that the near-field intermediate wave is dominating over the far-field spherical P and S pulses. The integral expressions are derived to related dilataiotn and rotatoin of scattering to the radial fluctuations of velocities and density in the inhomogeneity. These integrals are solved to calculate the stains of scattering from (a part of) an inhomogeneous spherical shell of arbitarary curvature. Varible curvature may allow the shape of of inhomogeneity volume element to change uniformly from spherical to rectangular. Rotation of scattering from a spherical shell is independent of P wave velocity inhomgeneity. Dilatation of scattering does not involve S wave velocity inhomogeneity but its gradient. The back scattering results are obtained as a special case. Stains are computed numerically, for hypothetical models to study the effects of various parameter viz., velocity inhomogeneity, distance of sour from inhomogeneity and from receiver, and thickness of inhomogeneity. The curvature of the psherical shell is varied to study the effect of the shape of inhomogeneous volume element on scattering.

5 illus, tables, 18 ref