006817   Jha M K (High School, Hulaspatti, Madhubani, Bihar) : Morphometric treatment of some linear aspects of the rivers around Gaya city. Indian J Landsc Syst ecol Stud 2009, 32(2), 189-96.

Of late, quantitative treatment of the geomorphic features has got an upper hand over the traditional descriptive hence, morphometric analyses have been ventured here to assess the linear properties of the rivers through the area around Gaya city. The evolutionary stage of the landscape may be gauged by the quantitative analyses and syntheses of the linear and relief aspects of the drainage networks. Here linear aspects have been preferred for ascertaining the geomorphic frame the region because of their decisive control on the other two aspects. Stream orders, bifurcation ratios, stream lengths, stream length ratios and the sinuosity indices are in tune with of R.E. Morton, A.N. Strahler, Savindra Sinha and J.E. Mueller with slight variations at places due to local structural and geomorphic restraints. In fine all the linear attributes of the drainage nets, working hand -in-hand, not only determine the geometry of their respective drainage basins but portray the stage of their geomorphic evolution also.

5 illus, 6 tables, 10 ref

006816   Jayagondaperumal R;Dubey A K;Sen K (NO, Wadia Institute of Himalayan Geology, Dehradun-248 001, Email: ramperu@wihg.res.in) : Structural and magnetic fabric studies of recess structures in the western Himalaya: implications for 1905 Kangra earthquake. J Geol Soc India 2010, 75(1), 225-38.

Kinematic information from deformation structures and magnetic fabrics are used to infer recent tectonics around Kangra and Dehradun recesses, western Himalaya. Three types of magnetic fabrics (Type I & II, III, and IV) are identified based on the angle between K3 axis and bedding pole. It was observed that Kangra recess shows more mature fabric type IV as compared to Dehradun recess, where orientation of K3 axes and tectonic fabric reveals dominance of superposed deformation. In the vicinity of Dehradun recess, normal faults occur in un-indurated Quaternary fan deposits confirming their recent formation. The observations are in conformity with earlier studies that during the 1905 Kangra earthquake, the Main Boundary Thrust (MBT) (or one of its subsidiary thrusts) near Kangra showed thrusting whereas the MBT near Dehradun underwent either normal faulting or post seismic adjustments characteristic of normal faulting. The thrusting could be a result of subsurface processes whereas the normal faulting was a result of prevailing surface strains.

8 illus, 2 tables, 156 ref

006815   Jain A K (Irrigation and CAD Dep, Government of India, Andhra Pradesh) : Internalizing negative externalities associated with groundwater development through watershed approach as related to organizational arrangement. J Hydrol 2009, 32(1), 153-6.

13 ref

006814   Hrouda F (NO, AGICO Inc., Jeena 29a, Box 90, CZ-621 00 Brono, Czech Republic, Email: fhrouda@agico.cz) : Modelling relationship between bulk susceptibility and AMS in rocks consisting of two magnetic fractions represented by ferromagnetic and paramagnetic minerals-implications for understanding magnetic fabrics in deformed rocks. J Geol Soc India 2010, 75(1), 254-66.

Measurement of Anisotropy of Magnetic Susceptibility (AMS) has become an important tool for Structural Geological analysis in the past few decades. In the past, AMS data have been used for petrofabric analysis of deformed rocks as well as for gauging strain. However, the AMS of some rocks can be carried by both ferromagnetic and paramagnetic minerals. Separating effects of these mineral groups on the rock's AMS is difficult because of expensive and commercially less available instrumentation. On the other hand, instrumentation is available in most rock magnetic and palaeomagnetic laboratories for resolving bulk susceptibility into ferromagnetic and paramagnetic components. Mathematical modelling was made of the relationship between bulk susceptibility and AMS. If the contribution of the ferromagnetic or the paramagnetic fraction to the rock susceptibility is dominant (let us say higher than 80%), the resultant AMS is relatively near to the AMS of the dominating fraction in all aspects, the degree of AMS, shape parameter and orientation of principal susceptibilities. In the interpretation of the AMS of rocks with dominating one fraction, the resolution of the AMS into paramagnetic and ferromagnetic components is not necessary, the resolution of bulk susceptibility into components is sufficient that can be made using the instrumentation available in most rock magnetic and palaeomagnetic laboratories.

7 illus, 45 ref

006813   Hota R N;Sahoo M (P.G. Geology Dep, Utkal Univ, Bhubaneswar-751 004, Email: rnhota@yahoo.com) : Cyclic sedimentation of the Karharbari formation (Damuda group), Talchir Gondwana basin, Orissa. J Geol Soc India 2009, 73(4), 469-78.

The cyclic arrangement of lithofacies of the Karharbari Formation of the Damuda Group from a part of the Talchir Gondwana basin has been examined by statistical techniques. The lithologies have been condensed into five fades states viz. coarse-, medium-, fine-grained sandstones, shale and coal for the convenience of statistical analyses. Markov chain analysis indicates the arrangement of Karharbari lithofacies in form of fining upward cycles. A complete cycle consists of conglomerate or coarse-grained sandstone at the base sequentially succeeded by medium-and finegrained sandstones, shale and coal at the top. The entropy analysis categorizes the Karharbari cycles into the C-type cyclicity, which is essentially a random sequence of lithologic states. Regression analysis undertaken in the present study indicates the existence of sympathetic relationship between total thickness of strata (net subsidence) and number and average thickness of sedimentary cycle and antipathic relationship between number and average thickness of sedimentary cycle. These observations suggest that cyclic sedimentation of the Karharbari Formation was controlled by autocyclic process by means of lateral migration of streams activated by intrabasinal differential subsidence, which operated within the depositional basin and the channels carrying coarse grade clastic sediments, which make the cycles thicker, tend to be more common in the areas of maximum subsidence. Clastic sediments issued from the laterally migrating rivers interrupted the cyclic sedimentation of the Karharbari Formation in many instances.

8 illus, 4 tables, 34 ref

006812   Hota R N;Das B K (P.G. Geology Dep, Utkal Univ, Bhubaneswar-751 004, Email: rnhota@yahoo.com) : Cyclic sedimentation of the barren measures formation (Damuda group), Talchir Gondwana basin: statistical appraisal from borehole logs. J Geol Soc India 2010, 75(3), 549-59.

The succession of lithofacies of a part of the Barren Measures Formation of the Talchir Gondwana basin has been studied by statistical techniques. The lithologies have been grouped under five facies states viz coarse-, medium-, and fine-grained sandstones, shale and coal for statistical analyses. Markov chain analysis indicates the arrangement of Barren Measures lithofacies in the form of fining upward cycles. A complete cycle consists of conglomerate or coarsegrained sandstone at the base sequentially succeeded by medium-and fine-grained sandstones, shales and coal at the top. The entropy analysis puts the Barren Measures cycles into A-4 type cyclicity, which consists of different proportions of lower, upper and side truncated cycles of lithologic states. Regression analysis indicates a sympathetic relationship between total thickness of strata (net subsidence) and number of cycles and an antipathic relationship between average thickness and number of sedimentary cycles. The cyclic sedimentation of the Barren Measures Formation was controlled by autocyclic process which occurred due to the lateral migration of streams triggered by intrabasinal differential subsidence. In many instances, the clastic sediments from the laterally migrating rivers interrupted the cyclic sedimentation resulting in thinner cycles in areas where the number of cycles are more. Principal component and multivariate regression analyses suggest that the net subsidence of the basin is mostly controlled by the thickness of sandstones, shale beds and coal stringers.

7 illus, 6 tables, 37 ref

006811   Hota P N (P.G. Geology Dep, Utkal Univ, Vani Vihar, Bhubaneswar-751 004, Email: rnhota@yhoo.com) : Coal correlation and intrabasinal differential subsidence-a case study from the Barakar formation of Talchir Gondwana basin, Orissa. J Geol Soc India 2010, 75(2), 403-10.

In case of autocyclic sedimentation, direct relationship exists between net thickness of strata and number of coal cycles. Many of the coal basins including coal bearing Gondwana basins of India are good examples of autocyclic sedimentation, in which the cyclicity is attributed to intrabasinal differential subsidence of the basin floor. In the present work an attempt has been made to quantify the intrabasinal subsidence in a part of the Barakar Formation of the Talchir Gondwana basin. Eight undisturbed intervals were delineated in the Barakar stratigraphy. During different phases of sedimentation, different parts of the study area subsided with varying magnitudes. The areas of maximum subsidence accommodated thicker sediment column in comparison to the areas of slow subsidence rate.

5 illus, 2 tables, 25 ref

006810   Heilbronner R (Environmental Sciences Dep, Geological Institute, Basel Univ, Basel, Switzerland, Email: renee.heilbronner@unibas.ch) : Mapping texture domains in quartzite microstructure. J Geol Soc India 2010, 75(1), 160-70.

Deals with the combined application of two methods for microstructure and texture analysis (1) optical orientation and misorientation imaging and (2) autocorrelation function (ACF). Using two different samples, the usefulness of the methods and the quality of the results are discussed. One sample is a quartzite layer from the limb of a small scale fold in the Suretta Nappe (Val Avers, Switzerland) which was deformed under upper greenschist conditions, the other is a sample of Black Hills quartzite, experimentally sheared in dislocation creep. Using the method of computer-integrated polarization microscopy (CIP), c-axis orientation and misorientation images were prepared and pole figures were calculated from the azimuth and inclination images. Misorientation images were prepared and analyzed in a number of ways: (1) In as much as misorientation images constitute texture maps, they visualize the geometry and spatial distribution of texture domains; they show if the texture domains are spatially coherent, i.e., if the rock is domainal or not. (2) Thresholded misorientation images allow the calculation of the volume fraction of texture domains, which is a means of estimating the texture intensification independent of the shape of the pole figure skeleton. (3) From the ACF of thresholded misorientation images the average grain size and shape in those domains can be derived. (4) From the shape of the domains (if they exist as spatial entities), the strain or strain partitioning as well as the Theological contrast can be estimated. The paper seeks to demonstrate the importance of localized texture analysis. The aim is to discuss the quality of the results that can be obtained. The samples were chosen because one is domainal the other one is not. A full discussion of the geological implications of the results of the analysis is outside the scope of this contribution.

4 illus, 3 tables, 33 ref

006809   Gupta S;Sarkar G (NO, PCMM & APC College, Kolkata, West Bengal) : Comparative analysis of fluvio-geometric characterestics of river Chamta and its principal stream river Panchnoi, North Bengal, West Bengal, India. Indian J Landsc Syst ecol Stud 2009, 32(2), 197-206.

In fluvial geomorphic analysis nature and character of the flow of streams is a significant factor which may control the valley shape, size, channel pattern and overall channel dynamics. Here in this paper the channel configuration of the River Chamta and Panchnoi have been studied by primary observation of field geomorphology. The study has been concentrated particularly on the view point of fluvial geomorphic aspects and five chapters in addition to conclusion and suggestions have been formulated for the specific study. A number of geomorphic parameters have been selected for study and mostly field data collected for specific objectives have been used for representation. Based on fluvio-metric principles a micro level study has been carried out for getting the geomorphic status of the studied stretch of the basin and a point to point observation, analysis and interpretation relating to the problems are considered for the problem specific study.

9 illus, 6 ref

006808   Gupta S;Das A;Goswami S;Modak A;Mondal S (Geology & Geophysics Dep, I.I.T., Kharagpur, Kharagpur-721 302, Email: saibl@gg.iitkgp.ernet.in) : Evidence for structural discordance in the inverted metamorphic sequence of Sikkim Himalaya: towards resolving the main central thrust controversy. J Geol Soc India 2010, 75(1), 313-22.

Inverted metamorphism in the Himalayas is closely associated with the Main Central Thrust (MCT). In the western Himalayas, the Main Central Thrust conventionally separates high grade metamorphic rocks of the Higher Himalayan Crystalline Sequence (HHCS) from unmetamorphosed rocks of the Inner sedimentary Belt. In the eastern Himalayas, the Inner sedimentary Belt is absent, and the HHCS and meta-sedimentary Lesser Himalayan Sequence (LHS) apparently form a continuous Barrovian metamorphic sequence, leading to confusion about the precise location of the MCT. In this study, it is demonstrated that migmatitic gneisses of the sillimanite zone in the higher structural levels of the HHCS are multiply deformed, with two phases of penetrative fabric formation (S1HHCS and S2HHCS) followed by third folding event associated with a spaced, NW-SE trending, north-east dipping foliation (S3HHCS). The underlying LHS schists (kyanite zone and lower) are also multiply deformed, with the bedding S₀ being isoclinally folded (F1LHS), and subsequently refolded (F2LHS and F3LHS). The contact zone between the HHCS and LHS is characterized by ductile, top-to-the southwest shearing and stabilization of a pervasive foliation that is consistently oriented NW-SE and dips northeast. This foliation is parallel to the S3HHCS foliation in the HHCS, and the S2LHS in the LHS. Early lineations in the HHCS and LHS also show different dispersions across the contact shear zone, implying that pre-thrusting orientations of the two units were distinct. The contact shear zone is therefore interpreted to be a plane of structural discordance, shows a shear sense consistent with thrust movement and is associated with mineral growth during Barrovian metamorphism. It may well be considered to represent the MCT in this region.

7 illus, 30 ref

006807   Gupta A (P.G. Dep of Geography, Jammu Univ, Jammu-180 006) : Landslides along western Himalayas and it's impact on the economy of the J&K state. Indian J Landsc Syst ecol Stud 2009, 32(2), 487-95.

Hazards occur without warning, and yet no landslide can take place unless the factor of safety or the ratio between the average shearing resistance of the ground and the average stresses on the potential surfaces of the sliding decreases from an initial value greater than one to unit at the instant of the slide. This ratio normally declines gradually and slope failure occurs; however, it may drop instantaneously during earthquakes. Many a time, observers fail to notice the phenomena that precedes the hazards, and so it may appear that hazards are sudden and surprise. Hence to overcome the loss, immediate remedial measures have to be taken to stabilize these hazards in order to revitalize the geo-ecology of the area.

4 illus, 3 tables, 10 ref

006806   Greiling R O;Obermeyer H (Institute fur Angewandte Geowissenschaften, Karlsruhe (TH) Univ, Hertzstrasse 16, 76187 Karlsruhe, Germany, Email: er8@agk.uka.de) : Natural electromagnetic radiation (EMR) and its application in structural geology and neotectonics. J Geol Soc India 2010, 75(1), 278-88.

Natural electromagnetic radiation (EMR) impulses are emitted from rocks under stress. Electromagnetic emission may start during crystal deformation prior to and during the nucleation phase of nanocracks. The emission direction is either parallel with or normal to the crack surfaces. The EMR magnetic component is measured by the sensor or aerial of an instrument, the Cerescope, at frequencies from 5 to 50 kHz. Measurements at the surface show directions of recent stresses remarkably well. A calibration of EMR intensity in terms of stress magnitude is possible in tunnels, where the overburden pressure can be calculated. Two examples from the Upper Rhine Graben and NW India show EMR line measurements. In both cases, stress concentrations at fault or bedding surfaces can be detected. These surfaces can be regarded as tectomcaliy ictivc. Two further examples of EMR determinations in tunnels give more detailed information on the regional stress field. The example from the Swiss Jura fold-and-thrust belt shows directional results, with different directions beneath and above the regional detachment horizon at the base of the belt. The example from central Scandinavia shows a late Caledonian shear zone as a boundary between two recent stress domains, and gives absolute values of stress.

8 illus, 47 ref

006805   Ghoshal S;Dedalal S S;Lahiri S C (Chemistry Dep, Kalyani Univ, Kalyani-741 235, Email: sujitclahiri@yahoo.com) : Comparative study on the geographical, physical and engineering properties of soils of West Bengal. part-II : field test (experimental methods) working equations and engineering properties of soils of North Bengal. J Indian Chem Soc 2009, 86(7), 703-10.

The experimental methods for the determination of mechanical properties of soils based on field tests, the basic equations for the determination of the design values of the bearing capacity according to the load of the superstructure and the properties of the sub soils have been described. The mechanical (engineering) properties of soil samples of North Bengal have also been described.

2 illus, 3 tables, 17 ref

006804   Ghosh S K;Sengupta S (Geological Sciences Dep, Jadavpur Univ, Kolkata-700 032, Email: sudiptasg@yahoo.com) : Paradoxical situation on determining relative competence from wavelength/arclength ratios within buckle folded multilayers. J Geol Soc India 2010, 75(1), 13-17.

By measuring the ratio of wavelength to arclength of folds in closely associated disharmonically folded competent layers, it is possible to determine which layer has undergone a greater layer-parallel strain and has a smaller competence. This method may lead to a paradoxical situation. For example when foliated quartzite and mica schist layers are folded together, the mica schist laminae show a much larger buckle shortening than the quartzite layers. On the other hand, the geometry of folds in quartzite indicates that quartzite was more competent than the mica schist. The structure can be explained by different modes of buckling, general buckling in quartzite layers and internal buckling in strongly anisotropic mica schists.

5 illus, 1 table, 12 ref

006803   Ghosh S (NO, Presidency College, Kolkata) : Classification of degraded land and its management, Purulia district, West Bengal, India. Indian J Landsc Syst ecol Stud 2009, 32(2), 415-22.

The supply of land on the earth's surface is limited and practically closed. It is controlling the pivot mechanism of primary production systems. Over the years, the country's landmass has suffered from different types of degradatip Land degradation is a serious threat to the world, not merely as an environmental issue, but also a socio-economic problem. In this regard the present paper concerns an attempt to the Ecological investigation, identification, status of distribution, extent and precise characteristics of different types of degraded land of Purulia district of West Bengal.

3 illus, 2 tables, 11 ref

006802   Ghosh Bobba A;Singh V P (Water Science and Technology Branch, National Water Research Institute, Environment Canada, Burlington, Ontario Canada L7R 4A6) : Eco watershed management approach to inter-connect rivers in India. J Hydrol 2009, 32(1), 96-124.

Many rivers in India are shared resources, flowing through or between more than one province and more than one country. The combined effect of climatic stochasticity, rapid population growth and inefficient water infrastructure is increasing stress on river basin ecosystems. As stresses on river basins continue to increase, water re-distribution schemes are rapidly assuming the status of a 'growth industry', but they have a potential for intra-and international conflict and for severe ecosystem perturbation. Despite their high cost and 'high profile' in terms of complex engineering and technical inputs that they require, the ecological and social implications of such schemes have been, and continue to be, inadequately addressed. Healthy freshwater ecosystems provide a wealth of goods and services for society, but our appropriation of freshwater flows must be better managed if we hope to sustain these benefits and freshwater biodiversity. This paper will propose a framework for developing an ecologically sustainable watershed management approach, in which human needs for water are met by storing and diverting water in a manner that can sustain or restore the ecological integrity of affected watershed ecosystems. The framework includes: (1) developing initial numerical estimates of key aspects of river flow necessary to sustain native species and natural ecosystem functions; (2) accounting for human uses of water, both current and future, through the development of a hydrologic simulation model that facilitates an examination of human-induced alterations to river flow regimes; (3) assessing incompatibilities between human needs and ecosystem requirements with particular attention to their spatial and temporal characteristics; (4) collaboratively searching for solutions to resolve incompatibilities; (5) conducting watershed management to resolve critical uncertainties that frustrate efforts to integrate human and ecosystem needs; and (6) designing and implementing an adaptive management program to facilitate ecologically sustainable watershed management for the long term. Drawing from case studies to illustrate the framework, this paper hypothesizes that ecologically sustainable watershed management is attainable for a vast majority of watersheds.

8 illus, 46 ref

006801   Gerik A;Kruhal J H;Caggianelli A (Tectonics and Material Fabrics Section, Technische Munchen Univ, Germany, Email: axel.gerik@geophysik.uni-muenchen.de) : Quantification of flow patterns in sheared tonalite crystal-melt mush: application of fractal-geometry methods. J Geol Soc India 2010, 75(1), 210-24.

Fractal-geometry-based analysis techniques offer simple and efficient ways for analyzing magmatic fabrics that are otherwise difficult to describe quantitatively. This study shows an application of two different methods on flow patterns observed in a syntectonic magmatic body injected into the lower crust. XZ and YZ rock cuts are scanned, and the scans are automatically transferred to binary patterns of mafic and felsic minerals. These are analyzed by box-counting as well as the modified Cantor-dust method. Box-counting leads to characterization of the entire patterns, proves their fractality in two different scale ranges, and yields information about magma mingling and grain-aggregate forming processes. The modified Cantor-dust method quantifies the anisotropy of pattern complexity and represents a potentially powerful method for determination of shear sense during magmatic flow. Both methods represent useful tools specifically for analyzing diffuse magmatic fabrics and for connecting field-related studies with analyses on the microscale.

10 illus, 41 ref

006800   Fazio E;Punturo R;Cirrincione R (Scienze Geologiche Dep, Corso Italia 57, 95129 Catania, Italy, Email: efazio@unict.it) : Quartz c-axis texture mapping of mylonitic metapelite with rod structures (Calabria, southern Italy): clues for hiden shear flow direction. J Geol Soc India 2010, 75(1), 171-82.

This quantitative microstructural study deals with textures of quartz domains within a mylonitized metapelite collected near a thrust surface corresponding to the tectonic contact between two metamorphic units, which crop out in the Aspromonte Massif, southern Calabria (Italy). The sample investigated lacks a mesoscopic stretching lineation. Therefore, quartz c-axis fabrics were investigated in two mutually orthogonal thin sections (a) parallel to the quartz rod lineation and perpendicular to the foliation (YZ plane) and (b) perpendicular to the quartz rods and perpendicular to the foliation (XZ plane); the data were generated using classical (manual measurements of quartz c-axis using U-stage) and modern methods (Computer Integrated Polarization microscopy). Both these sections show oblique foliations at ca. 40° from the main shear plane, implying that the actual X direction (stretching lineation that is absent on the mesoscopic scale) must lie between these two sections. Quartz c-axis data from the YZ section when rotated by 90° are similar with those from the XZ section. Hence, the data from the two sections are merged. These data when rotated by an angle of 50° from the direction of quartz rod lineation, gives an asymmetrical pattern indicating top-to-the-North sense of shear. This was confirmed by investigating quartz c-axis patterns in a section striking NS and perpendicular to the foliation. Based on the study it is thus concluded that this method can be used to do kinematic analysis in rocks that are devoid of stretching lineations. Apart from the above, the advantages and disadvantages of the classical and modern methods of quartz c-axis analysis are discussed.

8 illus, 24 ref

006799   Duraiswami R A;Dumale V;Shetty U (Groundwater Surveys and Development agency, Bhujal Bhavan, Shivajinagar, Pune-411 005, Email: raymond.duraiswami@gmail.com) : Geospatial mapping of potential recharge zones in parts of Pune City. J Geol Soc India 2009, 73(5), 621-38.

Runoff has increased many fold in urban areas due to increase in paved areas, training of streams and construction of storm water drains. The recharge is therefore continuously decreasing; resulting in depleting groundwater reserves beneath large cities, especially those situated on water divides. In order to reduce surface runoff and replenish groundwater many advocate artificial recharge through rainwater harvesting. Conventionally, detailed hydrogeological survey is needed by expert hydrogeologists to suggest suitable sites for rooftop rainwater harvesting and storage in the subsurface aquifers. Pune, a rapidly growing city, is under severe stress due to shortage of water in some areas. An effort has been made in this study to identify areas suitable for rooftop rainwater harvesting by integrating traditional hydrogeological survey data with the help of Remote Sensing and Geographic Information System. This endeavour has led to develop a program called SLUGGER-DQL which helps to identify potential sites for rooftop rainwater harvesting and artificial recharge. The program is open ended and several other factors controlling potential recharge can be easily added on. Based on the results of the present study, potential sites for rainwater harvesting and artificial recharge have been identified in the Pune University-Shivajinagar-Kothrud area. The present paper demonstrates the utility of traditional hydrogeological surveys combined with modem techniques in solving problems related to urban hydrogeology and town planning.

12 illus, 20 tables, 22 ref

006798   Druguet E;Castano M (MIET-Research Group, Geologia Dep, Autonoma de Barcelona Univ, 08193 Bellaterra (Barcelona), Spain, Email: elena.druguet@uab.cat) : Analysis of syntectonic magmatic veins at the mesoscale. J Geol Soc India 2010, 75(1), 60-73.

Syntectonic magmatic veins are useful tools to identify the interaction between magmatic and deformation processes in the lithosphere. They can be present at all crustal levels, scales and tectonic regimes. The structural analyses of sets of leucocratic veins and dykes from the Rainy Lake zone (Canada) and from Cap de Creus area (Spain), combined with the results of analogue deformation experiments, allows distinction between structures related to intrusion and emplacement, and structures related to post-emplacement deformation. This study also gives an insight on the influence of host rock rheology, regional thermal conditions and deformation history on the developed structures.

12 illus, 1 table, 44 ref

006797   Devaraju T C;Sudhakara T L;Kaukonen R J; Viljone R P;Alapieti T T;Ahmed S A;Sivakumar S (NO, , Rajamangala Saptapur, Haliyal Road, Dharwad-580 001, Email: tcdevaraju@gmail.com) : Petrology and geochemistry of greywackes from Goa-Dharwar sector, western Dharwar craton: implications for volcanoclastic origin. J Geol Soc India 2010, 75(3), 465-87.

Late Archaean Supracrustals of the Goa-Dharwar sector (GDS) are composed of a thick sequence of greywacke sequence with narrow intercalations of quartzite, BIF and carbonates. Mafic volcanics occupy the base of the sequence. The greywackes are predominantly tuffacious containing chlorite-sericite and hornblende. Arkosic variations containing biotite dominate the western part of the sector. Fine-grained variations occur as isolated narrow lenses within other types of greywackes. The conglomeratic greywackes are localized along the western and the eastern margins of the sector. All of the greywackes are all typically immature containing coarser clasts of mostly plagioclase (18-23%) and quartz (32-34%). Lithic fragments of felsic volcanic rocks are common. The matrix is dominated by mafic material. Biotite and amphibole are related to metamorphic recrystallization. Chlorite, sericite, epidote, carbonate and chert are products of the interplay of diagenesis and low-grade metamorphism. Fe-Ti oxide, sphene, apatite and zircon are usual accessories. But for slight enrichment in K₂O, the major element chemistry of the GDS greywackes is similar to the chemistry of Late Archaean greywackes. They also compare in respect of V, Co, Hf contents, K₂O/Na₂O, SiO₂/Al₂O₃, Na₂O/Al₂O₃, Ba/Rb, Th/U, La/Th, Sm/Nd ratios, steep REE patterns with distinct LREE enrichment and HREE depletion. The GDS greywackes however are distinctly enriched in Rb, Ba, Sr, Th, U, Cu, Zr, Ce/Ce* and depleted in Cr, Ni, and Zn. The conglomeritic and biotite bearing verities contain considerable proportions of clasts derived from the basement tonalitic/granitic terrain. The common tuffacious greywackes containing hornblende and biotite-sericite however include only volcanic clasts and bear evidence of derivation from submarine weathering of predominantly felsic volcanics erupted on a large scale to form a magmatic arc in the later stages of geosynclinal deposition. Geochemical data suggest that the GDS greywackes were laid down in progressively changing basin geometry from a passive to active continental margin and island arc setting.

16 illus, 4 tabls, 45 ref

006796   Dessai A G;Arolkar D B;French D;Viegas A; Viswanath T A (Earth Science Dep, Goa Univ, Taleigao Plateau, Goa-403 206) : Petrogenesis of the Bondla layered mafic-ultramafic complex, Usgaon, Goa. J Geol Soc India 2009, 73(5), 697-714.

The Bondla mafic-ultramafic complex is a layered intrusion that consists predominantly of peridotites and gabbronorites. A chromitite-pyroxenite-troctolite horizon serves as a marker to subdivide the intrusion into two zones. The Lower Zone displays gravity stratified layers of chromite that alternate with those of olivine, which up-section are followed by olivine+pyroxene-chromite cumulates. The Upper Zone comprises gabbroic rocks that exhibit uniform layering. On the basis of modal and cryptic variation exhibited by the minerals this zone can be subdivided in to several lithohorizons starting from the troctolites at the base to gabbronorites and leucogabbros at the top. The junction between the two zones is marked by the distinct reversal in cryptic variation exhibited by the chromites and pyroxenes. The peridotite chromites contain higher AI₂O₃ and lower Cr₂O₃ than those from the chromitite above. Similarly clinopyroxenes from pyroxenite and troctolites are more magnesian that those from the peridotites stratigraphically below them. The complex in general is characterized by a gabbroic mineral assemblage in which both Ca-rich and Ca-poor pyroxenes coexist and displays a Fe-enrichment trend providing evidence of evolution from a contaminated tholeiitic magma. The rocks are characterized by low-TiO₂; Ni, Cr and V, show negative correlation with Zr whereas the large ion lithophile elements (LILE) are positively correlated and the Nb/La ratio varies from 0.4-0.6. These characteristics are consistent with a low-TiO₂ sub-alkaline tholeiilic magma that may have been modified by fractional crystallization and successive injections of more primitive melts in the magma chamber. The complex evolved in a periodically replenished magma chamber that consisted of two separate but interconnected sub-chambers.

17 illus, 7 tables, 39 ref

006795   Desbarats A J;Koenig C;Beckie R D;Pal T; Mukherjee P K (NO, Geological Survey of Canada, Ottawa, Canada) : Integrated geological, hydrogeological, geochemical and geophysical study of arsenic polution in groundwater of Gotra area, West Bengal part B: Hydrogeology. Indian J Geosci 2010, 64(1-4), 127-38.

Characterisation of the groundwater flow system at the Gotra field site involved the installation of a network of monitoring wells, some of which were instrumented with data loggers for the continuous recording of water levels as well as electrical conductivity, pH and temperature. The potentiometric data, hydrometeorological data from nearby weather stations, as well as hydrostratigraphic data were used to develop a preliminary steady-state numerical (MODFLOW) groundwater-flow model of the site. Groundwater flow-paths determined from the model show that observed high arsenic concentrations can be traced back to organic-rich sediments filling an abandoned river channel.

14 illus, 1 tables, ref

006794   Chowdhury S R (Geography Dep, Calcutta Univ, West Bengal) : Morphometric analysis of Kharsoti river basin in east Singhbhum district, Jharkhand using remote sensing and GIS techniques. Indian J Landsc Syst ecol Stud 2009, 32(2), 475-82.

Measurement of drainage basin interms of its linear aspect of morphometrie analysis of kharsoti river basin of East Singhhhum district in Jharkhand was carried using Remote sensing and GIS techniques. High Spatial Resolution Indian Remote Sensing Satellite (IRS)-P6 Linear Image Self Scanning (LISS)-IV sensor datu of October 2008 in conjunction with Survey Of India (SOI) topographical sheets (1:50.000 scale) were used for systematic analx sis of various morphometrie study. Detailed drainage map preparfed from satellite imagery and SOI toposheets werw used for the morphpmetric analysis of the Kharsoti basin. The basin shows dendritic, Sub dendritic, parallel drainage pattern with coarser drainage texture. High bifurcation ratio indicates a strong structural control on the drainage. Logarithm of number of stream vs Stream order show deviation from the straight line indicating regional upliftment. In spite of hilly relief, low drainage density value indicates that the area is underlain by impermeable sub-surface material. Circulatory and elongation ratios show that the basin has oval shape. The study demonstrates that remotely sensed data and GIS based approach is found to be more appropriate than the conventional methods in evaluation and analysis of drainage morphometry.

2 tables, 14 ref

006793   Chowdhury B K;Roy M K;Chaudhuri S;Marjan Kheleda;Roy D K (Geology and Mining Dep, Rajshahi Univ, Bangladesh, Email: mkr_c@yahoo.com) : Storm hazards along the Bangladesh coast with special reference to eastern region. Indian J Landsc Syst ecol Stud 2009, 32(2), 65-78.

The present work is an endeavor to give some information regarding storm along the coast of Bangladesh. It reports results concerning hazard perception caused by storm and choice of adjustment of the people in the coastal areas of Bangladesh. The analysis of storm data on the whole coastal region shows that the frequency and magnitude of cyclones are increasing day by day. The incidence of severe cyclones increased since 1890s reaching peak in the period between 1960s and 1970s. The intensity of cyclones is also increasing. During the time period of 1971 to 1990, the intensities of cyclones were more or less moderate. But since 1991 both the intensity and magnitude of I'u-lones are increasing. The result shows that the frequency of occurrence of cyclones at the class interval of 3 years, except for the class ranging from <60>1 to 2 years. It is observed that the most frequent occurrence of cyclones in all the regions took place in <60>1 to 2 years interval. The DFT/FFT(power spectrum) indicates that the periodicities of 105, 70, 30 and 23.3 years for the occurrence of severe cyclones. It reveals that the eastern region (ER) witnessed greater number of occasions when more than one storm took place in a single year than central and western region (CR and WR) considered together. Such a distribution of the number of severe cyclones accompanies a higher frequency of cyclones in this region in recent years than the other regions. Obviously, the ER is more hazardous than the other two regions in term of wind speed and number of occurrences. This zone was very much affected by hazardous activities of storms and tides in recent years. So, this coast is very much dangerous for lives, properties and any type of development works, which need more precaution measures to minimize those losses. It is clear that the coastal areas are free from cyclonic storms during the month of January, February and March. Bui the month of May has witnessed the highest number of occurrence-21 severe cyclones in 210 years. it may be said that though depressions are numerous in June to September, the month of May, October and November are span of occurrence of majority of the most severe storms. The month of October with 19 occurrences of cyclone in 210 years is also very prone to cyclones. Barring some exceptions, as in 1970, cyclones are less frequent in the month of November and December. In the month of May, the cyclones initially moved north then turned to the northeast and struck the coast of Chittagong and also affected the coastal belt of Noakhali, but the cyclones in the month of November and December move in northwesterly to northerly direction and then to the northeast.

12 illus, 2 tables 26 ref

006792   Chattoraj S L;Banerjee S;Saraswati P K (Earth Sciences Dep, Indian Institute of Technology Bombay, Powai, Mumbai-400 076, Email: santanu@iitb.ac.in) : Glauconites from the late palaeocene-early eocene Naredi formation, western Kutchh and their genetic implications. J Geol Soc India 2009, 73(4), 567-74.

Glauconitic minerals are considered as one of the valuable input parameters in sequence stratigraphic analysis of a basin. In the present study glauconitic minerals are reported from subtidal green shale facies in the lower part of the Late Paleocene-Early Eocene Naredi Formation of western Kutch. On the basis of the foraminiferal assemblage the glauconite bearing beds are interpreted to have formed in a mid shelf depositional settings of an unstable marine conditions. XRD studies confirm the glauconite mineralogy of the green pellets and provide an estimation of glauconite maturity. Textural attributes of the glauconites confirm their derivation by different degrees of alteration of precursor feldspar grains. Because of the authigenic origin and autochthonous nature, these glauconites hold promise for understanding sequence stratigraphy of the Palaeogene succession of the western Kutch.

4 illus, 2 tables, 24 ref

006791   Chatterjee N (Geography Dep, Presidency College, Kolkata) : Wetlands of the Rarh region of West Bengal [case studies of Nangalhata and Belun wetlands]. Indian J Landsc Syst ecol Stud 2009, 32(2), 389-96.

Wetlands constitute rich ecosystems. They have flood cushioning effects. The wetlands of Rarh Bengal are winked to the decaying of the Bhagirathi as the main flow of the Ganga shifted eastwards. Backflow from Bhagirathi was responsible for their development. The Nangalhata Wetland and Belun Bil Zone form two of the most important wetlands. Nangalhata remains seasonally submerged during the rainy season. This area has more or less remained the same. The seasonal submergence has influenced the land use pattern. Belun Bil Zone is formed by a linear arrangement of large bils. These are permanent water bodies influencing cultivation patterns. Seasonally inundated area is extremely large. Fishing is carried out in both the wetlands. The main problem faced is that of floods due to overflow from sluggish rivers and breaches in embankments.

1 table, 5 ref

006790   Chandrasekhar P;Vinod Kumar K;Martha T R; Subramanian S K (Space Dep, National Remote Sensing Centre (NRSC), Govt. of India, Hyderabad-500 625, Email: chandrasekhar_p@nrsc.gov.in) : Multi earth observation data to identify indicators for mineralized zones in parts of Iran. J Indian Geophys Union 2009, 13(3), 133-8.

Multi-sensor satellite data such as IRS P6 (RESOURCESAT 1) - LISS IV MX and LISS III, and IRS P5 (CARTOSAT 1) - PAN A were used for the identification of possible locations of chromite occurrence in a highly inaccessible area having less vegetation cover in the north eastern parts of Iran around Gaft region in the south western portion of Joghatay city. The coarse resolution LISS III data were used mainly for the regional understanding of the geological and geomorphological set up of the area, and the fine resolution PAN A data for delineating the microgeomorphological features. These two data sets were merged and hybrid images were generated in order to obtain the best of spatial and spectral interpretations, particularly for enhancing the minor spectral and spatial components of the lithological units. The existing field data i.e., the coordinates of the mineralized zones, collected using Global Positioning System (GPS) were plotted on the image and studied in conjunction with the multi-sensor data interpretation. The typical spectral signatures observed over known chromite mineralization are correlated with the unknown areas using mainly the lithological controls. The mineralization in this area is mostly controlled by lithology, and wherever these signatures matched, those areas are identified as prospective areas for chromite mineralization.

4 illus, 4 ref

006789   Bose S;Mandal N (Experimental Tectonics Laboratory, Geology Dep, Calcutta Univ, Kolkatta, Email: bose.santanu@gmail.com) : Interaction of surface erosion and sequential thrust progression: implications on exhumation processes. J Geol Soc India 2010, 75(1), 338-44.

This paper investigates the evolution of thrust wedges with concomitant surface erosion, and its bearing on the exhumation processes in orogenic belts. We performed sandbox experiments, simulating syn-orogenic erosion on forelandward sloping surfaces (<126>-4°). Experiments show that the erosion process has a significant control on the progression of frontal thrusts. In case of no-erosion condition, wedges with high basal friction develop frontal thrusts with strongly increasing spacing. In contrast, for the same basal friction the thrusts show uniform spacing as the wedge development involves concomitant surface erosion. On the other hand, the erosion promotes reactivation of hinterland thrusts in wedges with low basal friction. We show that erosion-assisted thrust reactivation is the principal mechanism for exhumation of deeper level materials in orogens. Efficiency of this mechanism is largely controlled by basal friction. The exhumation of deeper level materials is limited, and occurs within a narrow, sub-vertical zone in the extreme hinterland when the basal friction is high (μβ = 0.46). In contrast, the process is quite effective in wedges with low basal friction (μβ =0.36), resulting in exhumation along gently dipping foreland-vergent thrusts as well as along thrusts, subsequently rotated into steep attitude. The zone of exhumation also shifts in the foreland direction in the course of horizontal movement. Consequently, deeper level materials cover a large area of the elevated part of the wedge.

4 illus, 34 ref

006788   Biswal T K;Thirukumaran V;Ratre K; Bandyapadhaya K;Sundaralingam K;Mondal A K (Earth Sciences Dep, Indian Institute of Technology Bombay, Powai, Mumbai-400 076, Email: tkbiswal@iitb.ac.in) : Study of mylonites from parts of the Salem-Attur shear zone (Tamil Nadu) and its tectonic implications. J Geol Soc India 2010, 75(1), 128-36.

The E-W running Salem-Attur shear zone demarcates the tectonic boundary between Archaean Dharwar Craton in the north and Proterozoic Southern granulite terrane in the south. This study reveals that the shear zone is a low angle thrust. The thrust zone is around 10 m thick and it merges with the main shear zone along the strike. The thrust is developed on charnockite near Odyarpatti, which is retrograded into schists. Further, it is marked by gently dipping mylonitic foliation and subhorizontal lineation. The S-C fabric, mantled porphyroclasts and intragranular faults indicate northeasterly slip along the thrust. Recumbent shear folds SF₁ are developed within the thrust zone. The thrust has been folded by late stage F₂ fold which has brought variation in the orientation of the mylonitic foliation from subhorizontal to vertical attitude; the mylonitic lineations have been rotated to subvertical orientation also. Additionally, the F₂ crenulations and shear cleavages and intersection lineations are superimposed on the mylonitic fabric. Thrusting along the Salem-Attur shear zone is probably the cause for upliftment of the charnockites to the upper crust. Post-upliftment stage has witnessed brittle deformation in the form of development of shear fractures in NNE-SSW and E-W directions. Pseudotachylites are emplaced along these fractures.

8 illus, 22 ref

006787   Bhattacharjee D (Geography Dep, F.C. College, Diamond Harbour, South Harbour, South 24 Parganas, West Bengal) : Natural hazards and their management with special reference to varunavat landslides in Uttarkashi area. Indian J Landsc Syst ecol Stud 2009, 32(2), 143-54.

The Himalaya is considered to be the youngest mountains on the earth, and is tectonically very active, and hence inherently (geologically) vulnerable to hazards. The state of Uttaranchal has been witnessing a number of natural disasters, which include earthquakes, landslides and flash floods. Some of these disasters affected Uttarkashi and surrounding regions in the recent past. The study area (Uttarkashi) is now under various alarming problems like ladslides, flash floods, storm, avalanche, earthquake etc. Among them landslides disasters in the Himalayan mountains are very common. The study area has suffered a high degree of tectonic activity in the geological past, which is manifested by its geological setting and geomorphic features. The Himalayas being the highest mountain chain on the earth, are marked by very high relief and intense erosional activity. As a result of weathering and denudational processes, enormous amount of debris is released from the region. The natural rock waste may travel as a debris flow. A landslide disaster occurred in Uttarkashi on 24 September 2003, which has affected a part of the town especially in Varunavat hill area. The paper highlights the probable causes of the slide, of instability in the Varunavat hill and risk assessment.

10 illus, 7 ref

006786   Bhatt K M;Santosh Kumar (NO, Institute of Seismological Research, Sector 18, Gandhinagar-382 018, Email: kmbhatt@rediffmail.com) : Anomalous b-value in seismogenic layer of Bhuj region. J Indian Geophys Union 2009, 13(3), 99-106.

The earthquake size distributions follow, in most instances, a power law and slope of this power law, defines the 'b-value'. The parameter b is believed to depend on the stress regime and tectonic character of the region. High and low b-value probably means low and high stressed zone, respectively. Fault/faults has tendency to accumulate the stress. Depth wise, unalike segments of fault act in their own way for stress accumulation, depending on geology and rheology. For study, Bhuj aftershock zone is considered, which chiefly underlies two faults i.e. North-Wagad (NWF) and Bachau fault (BcF). The b-value study of this zone, distinctly demarcates faulted line and its different segment linked b-value are found in correlation with the stress-accumulation. It gives a very clear picture that b-value is not only helpful in demarcation of faulted depth line but also in prediction of segments of stress accumulation. This may help in study of earthquake prediction. The studies reveal that the b-value more often decreases with depth. This worldwide behavior is found to be valid for about 32% of the entire seismically active crust, at the 99% confidence level. About 2% of the crust only displays the opposite b-gradient. Kachchh is among the rare seismically active crust, which shows negative b-gradient. One plausible explanation for reverse characteristic of b-value could be the styles of faulting.

5 illus, 29 ref

006785   Bhardwaj S K (NO, Indian Institute of Geomagnetism, Plot No. 5, Sector-18, Kalamboli (Highway), New Panvel (W), Navi Mumbai-410 218, Email: sandeep@iigs.iigm.res.in) : Equatorial and low latitude geomagnetic field oscillations in the Indian region. J Indian Geophys Union 2009, 13(3), 107-20.

Monthly mean hourly values of geomagnetic field components D, H and Z for quiet days at equatorial and low latitude stations in the Indian region are analyzed to study the salient features of geomagnetic field oscillations in magnetic elements. The data used in this analysis is from 1958 to 1993 at equatorial electrojet stations: Trivandrum &. Annamalainagar, from 1970 to 1993 at Kodaikanal and from 1927 to 1997 at low latitude station Alibag. From this basic data, geomagnetic Sq ranges and summed ranges are computed and subjected to the data adaptive, noise reducing technique of Singular Spectrum Analysis (SSA). The pair of eigen vectors analyzed through SSA up to order 18 represent different oscillations of the field such as; 11-year, annual, semi-annual, 4-month, 14-month (Pole-tide) and a Quasi-Biennial Oscillation (QBO) etc. The Sq ranges, summed ranges at all the stations and monthly mean sunspot numbers for the same period are also analyzed by a band pass digital filter method in order to identify whether QBO signal at these stations is the result of dynamo winds or due to QBO like signature in the Sun's atmosphere. It is found that, the amplitude of the signal is stronger at equatorial electrojet stations in comparison with low latitude station Alibag and may be due to solar origin.

11 illus, 33 ref

006784   Bell T H;Hobbs B E (School of Earth and Environmental Science, James Cook Univ, Townsville, Qld 4811, Australia, Email: tim.bell@jcu.edu.au) : Foliations and shear sense: a modern approach to an old problem. J Geol Soc India 2010, 75(1), 137-51.

Argument about shear on foliations began in the mid 19th century and continues to the present day. It results from varying interpretations of what takes place during the development of different types of foliations ranging from slaty cleavages through differentiated crenulation cleavages, schistosity and gneissosity to mylonites. Computer modelling, quantitative microstructural work and monazite dating have provided a unique solution through access to the history of foliation development preserved by porphyroblasts. All foliations involve shear in their development and most can be used to derive a shear sense. The shear sense obtained is consistent between foliation types and accords with recent computer modelling of these structures preserved within porphyroblasts relative to those in the matrix. The asymmetry of curving foliation into a locally developing new one allows determination of the shear sense along the latter foliation in most rocks. The problem of shear on fold limbs and parallelism of foliation and the flattening plane of the strain ellipse is resolved through the partitioning of shearing and shortening components of deformation into zones that anastomose around ellipsoidal domains lying parallel to the XY plane. Conflicts in shear sense occur if multiple reuse or reactivation of foliations is not recognized and allowed for but are readily resolved if taken into account.

14 illus, 79 ref

006783   Beckie R D;Desbarats A J;Koenig C;Pal T; Mukherjee P K;Vaive J E (NO, British Columbia Univ, Vancouver, Canada, Email: rbeckie@eos.ubc.ca) : Integrated geological, hydrogeological, geochemical and geophysical study of arsenic pollution in groundwater of Gotra rea, West Bengal part C: Groundwater chemistry. Indian J Geosci 2010, 64(1-4), 139-54.

Gotra village in Chakdah block, Nadia district of West Bengal is one of the worst arsenic polluted areas where majority of the aquifers yield groundwater with high arsenic. An integrated geological, hydrological, geochemical and geophysical study has been carried out in and around Gotra village. This paper presents the groundwater chemistry in detail to explain the release mechanism of the pollutant into the groundwater. Groundwater, in all available 54 tubewells of variable depths, in Gotra village, is analysed for field parameters like temperature, pH, conductivity, DO, alkalinity, ammonia, and also for elemental abundance. The dissolved arsenic shows strong positive correlation with ammonia and alkalinity; weak positive correlation with iron, calcium and magnesium; but weak inverse correlation with dissolved oxygen, manganese and sulphur. The high-arsenic groundwaters are characterised by elevated concentrations of base cations like Ca, Na, Mg, K. Stable isotope (5δ²H and δ¹⁸O) concentrations of high-arsenic groundwater suggest that these waters represent direct recharge from precipitation. Groundwater geochemistry suggests that a reductive desorption process is acting as the principal mechanism for creating arsenic pollution in Gotra groundwater.

10 illus, 3 tables, 18 ref

006782   Basu A (Geological Sciences Dep, Indiana Univ, 1001 East 10th Street, Bloomington, IN-47405, U.S.A., Email: basu@indiana.edu) : Ediacaran fossils in meso and paleopraterozoic rocks in Peninsular India extend Darwin. J Geol Soc India 2009, 73(4), 528-36.

Typically or arguably Ediacaran fossils (635 Ma to 543 Ma) are reported by several research groups from one unit of the Chhattisgarh and two units of the Vindhyan Supergroups in peninsular India. Depositional ages of the host sediments, however, are inferred to be <126>1000 Ma and<126>1630 Ma as determined by U-Pb dating of magmatic and detrital zircons in rhyolitic tuff (<126>porcellanite) and sandstones, provenance considerations and paleopole positions. The contradiction of absolute ages results from inferring the Ediacaran age strictly on the basis of fossils. I argue that the fossils reported from the Chhattisgarh and Vindhyan Supergroups should be considered mostly Mesoproterozoic and late Proterozoic in age. I also argue that although the Ediacaran Period records explosive diversity of preserved fossils, many forms very likely appeared much earlier with variable degrees of preservation or none at all at times, and, that their age-ranges extend to the Paleoproterozoic. I hypothesize that the rate of increase of biological diversity was lower than the rate of preservation in certain geological intervals, especially immediately after extinction events.

2 illus, 2 tables, 108 ref

006781   Baskey S K;Jana N C (Geography Dep, Burdwan Univ, Burdwan-713 104) : Pedogeomorphic characteristics of lateritic catena and land use patterns in Patrasayer mouza, Bankura district. Indian J Landsc Syst ecol Stud 2009, 32(2), 445-52.

There is a close relationship between slope and landuse. According to the variations in slope, characteristics of surface soil, soil profile characteristics, nature of land degradation and land use patterns vary. The present paper deals with the relationship between pedogeomorphic characteristics of lateritic catena and land use patterns in Patrasayer Mouza of Bankura District, West Bengal.

6 illus, 5 tables, 10 ref

006780   Barman D (Centre for the Study of Regional Development, Jawaharlal Nehru Univ, New Delhi) : Green revolution and it's ecological impacts. Indian J Landsc Syst ecol Stud 2009, 32(2), 181-8.

Green revolution is a unique event in the agricultural history of the world, it has dramatically increased the production especially the food crops, never before such a tremendous growth of production occurred in the agricultural sector of the world, it has saved the world from the situation of hunger, food shortage, and famine, unprecedented green revolution also has the adverse effect on our ecology and environment. Green on is basically a package; the success of it depends on cultivation of high yielding varieties of crops. typically depends on the application or input of chemical inorganic fertilizers, pesticides, and irrigation, he other characteristics of green revolution is the cultivation of paddy and such food crops in semi arid parts ol the world, though they require supply of water in constant level. Since the 1960's when green revolution commenced through the invention of the high yielding variety of seeds, the transfer of technology from the world to the 3rd world countries has spread this modern high productive scientific agriculture all over the world which, is based on immense input of fertilizer, pesticides, and irrigation. The traditional methods of fertilizer like use of cow dung, green compost manures were replaced by the use of chemical fertilizers in the production purposes. The growing period of the new genetically modified dwarf was much less, it also leads multiple cropping of the land, but without giving the land the chance to make itself ready for a another cultivation. Thus the rotation process of crops also slowly starts disappearing. The use of number of tube wells increases to get water for the crops reduces the ground water level drastically. On the other hand canal irrigation extended the salinity and water logging. The total dependency on the chemical fertilizers increases the decaying of soil through the loss of its chemical properties. The use of pesticides contaminated the groundwater. increases | the resistance of the pests more, and threatening the ecology of aquatic systems through polluting it and by the process of eutriphication. So the Green Revolution creates a situation where our ecology and the environment continuously threatening by it. The present paper has been written keeping in mind with the ecological and environmental impacts of the green revolution.

19 ref

006779   Balai C M;Yadav K K;Majumdar P S (NO, K.V.K., Dungarpur, Rajasthan) : Effect of compaction on bulk density, saturated hydraculic conductivity and moisture content of soil. J Hydrol 2009, 32(1), 87-95.

A field experiment was conducted at Agronomy farm, S.K.N. College of Agriculture, Jobner to study the effect of compaction on bulk density, hydraulic conductivity and moisture content of soil during kharif seasons of the year 2002 and 2003. The experiment was consisting of three levels of compaction 0, 2 and 4 passing of 500 kg iron roller. The results revealed that four passing of 500 kg iron roller increase the bulk density and moisture retention at all stages and decreased saturated hydraulic conductivity of soil having maximum values in 15-30 cm soil layer.

3 tables, 10 ref

006778   Asthana S P;Suresh Ram;Mondal M K (D.A.V. College, C.S.J.M. Univ, Kanpur, Uttar Pradesh) : Ichhamati basin, W.B.: transformation of occupational structure and its impact on agriculture. Indian J Landsc Syst ecol Stud 2009, 32(2), 241-8.

Occupational structure is the pillar of the economy in an area. Among complex problems of our country, agriculture emerged as fundamental problems. The two basic problems are: One is to face the growing demand for food and other agricultural product by the ever-increasing population. Second is to reduce the widespread real poverty in rural area because it is inversely related to agricultural production. Thus, by increasing the level of agricultural productivity both purposes can be solved. The scientific ideas of productivity patterns and the factors generated them can help to improve agricultural production through development programs. Present study is concerned with the identification and analyses of transformation (1981-2005) of occupational structure of the Ichhamati basin area and will also try to provide guidelines for sustainable development.

2 illus, 2 tables, 11 ref

006777   Appala Raju N (Geography Dep, Andhra Univ, Visakhapatnam-530 003) : Landuse efficiency in Vizianagaram district, Andhra Pradesh. Indian J Landsc Syst ecol Stud 2009, 32(2), 385-8.

India's future is threatened by shortage of food, water and energy and these should be given priority. Agricultural productivity has to be enhanced to meet the increasing demand of ever growing population of the country. This challenging task is feasible by increasing the area of land in agriculture and by enhancing the level of production on sustainable basis. The present study is an attempt to assess the agricultural landuse efficiency in Vizianagaram district of Andhra Pradesh. The study is based on positive variables such as net sown area, area sown more than once, irrigated area to the cultivated area, irrigated area more than once, high yielding varieties, and commercial cropping. The higher the positive parameters the better will be the landuse efficiency.

1 illus, 1 tables, 10 ref

006776   Anjali R;Mohan Kumar G;Sampath S (NO, Centre for Earth Science Studies, PB 7250, Thiruvananthapuram-695 031, Email: anjalimeera@gmail.com) : Observed local enhancements in atmospheric carbon monoxide during biomass burning events. J Indian Geophys Union 2009, 13(3), 163-72.

An attempt is made to present the observed enhancements in atmospheric carbon monoxide (CO) associated with local biomass burning events at a tropical coastal environment Thiruvananthapuram (8° 29' N, 76° 57' E) and with approximations to compare these epochs with empirical estimates. An IR analyzer (Monitor Europe 9830B) was used for the continuous CO monitoring. CO emitted from two massive biomass burning events, including fresh biomass and dry biomass burning near the measurement site, -200 m were measured and estimated empirically. CO measured using the analyzer showed about 30- fold and 27- fold enhancements compared to normal days. Emperical estimates of CO showed 0.287 kg/m² CO emission on fresh biomass burning and 0.198 kg/m² on dry biomass burning. Enhancement in CO during two grassland burning events occurred at a high altitude location about 20 km from the measurement site were studied and about 1.5 fold and 1.4 fold enhancements in CO respectively were observed. Local enhancements in CO during massive biomass burning in open associated with religious festivals were also investigated in the present study.

9 illus, 14 ref

006775   Anil Kumar;Mishra N;Nayal B (NO, G.B. Pant Agricultural & Technology Univ, Pantnagar, Uttarakhand) : Assessment and management of meteorological drought for crop planting in Tarai region of Uttarakhand. J Hydrol 2009, 32(1), 76-86.

The distribution of rainfall in the Tarai region of Uttarakhand is very erratic in space and time and occurrence of occasional droughts is not uncommon. In this study 44 years (1961 to 2004) of rainfall data of Pantnagar have been analyzed on annual, seasonal, monthly and weekly basis for predicting the expected rainfall at different probability levels to determine periods of water deficit and surplus for crop planning in the region. The analysis has revealed that the assessment of drought on weekly basis is very important for better crop planning particularly in rainfed areas. It has also been revealed that there is a need to adopt measures for assured irrigation to mitigate the effect of drought during the pre-monsoon (summer) and post-monsoon (winter) crops, and a provision of supplemental irrigation or in-situ moisture conservation measures to meet dry-spells during monsoon season. It also provides important information about implements of drainage measures at suitable time and place during the periods of surplus surface runoff.

3 tables, 12 ref

006774   Ajay Kumar;Birua S N S;Pande D;Nath A R; Ramesh Babu P V;Pandit S A (Atomic Energy Dep, Atomic Minerals Directorate for Exploration and Research, Khasmahal, Jamshedpur-831 002, Email: priyanapur@redifmail.com) : Radioactive quartz-pebble conglomerates from western margin of bonai granite plution, Sundargarh district, Orissa-a new find. J Geol Soc India 2009, 73(4), 537-42.

Several radioactive quartz-pebble conglomerate (QPC) occurrences at the western margin of Archaean Bonai granite and overlying Iron Ore Group (IOG) rocks have recently been located over a total strike length of 8-10 km intermittently in a NE-SW to E-W trend with steep dips due north- west to north in parts of Sundargarh district of Orissa. The QPC samples have analysed up to 0.039% U₃O₈ and 0.035% ThO₂ with high concentration of Y (74 to 518 ppm), La (<60>100 to 880 ppm), Cr (126 to 633 ppm), Zr (137 to 1250 ppm) and Pb (31 to 581 ppm). Cellulose Nitrate (CN) film studies of few QPC samples indicated adsorbed uranium over goethite and infiltrated ferruginous material (limonite), secondary uranium as encrustation and fracture filling and discrete sub-rounded grains of monazite, zircon, allanite and rare xenotime in the matrix of QPC as radioactive phases. Higher content of Th over U, elevated concentration of Y and La in QPC eliminates the possibility of its low temperature product by epigenetic processes. Poor correlation of U with elements like Pb, Y, Zr, La and Cr can be explained due to surficial leaching of uranium from QPC after its deposition as reflected by adsorbed U over iron- oxides and low U/Th ratio in QPC in the area.

4 illus, 2 tables, 15 ref

006773   Agrawal M (Geography Dep, B.H.U. Univ, Varanasi) : Fluvial morphometry of third order drainage basins of satpura upland: a case study of Jabalpur plateau, M.P. India. Indian J Landsc Syst ecol Stud 2009, 32(2), 371-84.

Drainage basins, which represent one of the most important topographical feature of the earth surface, bear distinct stamp of multiple action of lithology, structure, climate, relief etc. The present paper deals with the frequency distribution of morphometric elements of only third order drainage basins of a part of Satpura upland situated in the south-eastern part of Jabalpur district, M. P. India. In this region entire Satpura upland is covered by thick sheets of volcanic lava with the Lameta beds exposed along its slopes. Due to marked topographical variations this upland can hardly be treated as a single unit, but is divided in three regions, viz, Eastern Satpura upland, South - eastern Satpura upland and Western Satpura upland. In the selected area 234 third order drainage basins have been delimited. The procedure followed has yielded 74 basins in eastern Satpura upland, 85 basins in the south - eastern Satpura upland and 75 basins in western Satpura upland. The analysis includes the frequency distribution of absolute relief, relative relief, basin area, number of first order streams, drainage density, drainage frequency, elongation ratio and basin slope of third order drainage basins only. From the analysis, it has become apparent, that, in general, the basins of Satpura upland have medium altitude, moderate relief, small drainage basins, low number of first order streams, moderate drainage density, medium drainage frequency, intermediate circularity and moderate slope. Due to similar lithological structure, the three sub regions of Satpura upland, mentioned above, exhibit somewhat similar characteristics, though, there are slight variations in the distribution of some of the morphometric elements. As for example, the drainage basins of eastern Satpura have medium altitude with comparatively higher relief, higher dainage frequency, higher drainage density, intermediate circularity and relatively steeper slope. Whereas the basins of south - eastern Satpura upland are situated at comparatively higher elevations, but here the relief is relatively low and slope is comparatively gentler. The values of both drainage density and drainage frequency are also slightly lower than in the case of eastern Satpura upland. The drainage basins of western Satpura upland are situated at comparatively lower elevations with less dissected topography. They exhibit relatively low relief, poor drainage density, low drainage frequency and gentler slope. But here the basins are larger in size and have higher elongation ratio.

8 tables, 19 ref

006772   Agarwal K K;Jahan N;Agarwal A (Centre of Advanced Study in Geology, Lucknow Univ, Lucknow-226 007, Email: kamalagarwal73@gmail.com) : Modification of fold geometry in Almora crystaline shear zone, lesser Himalaya, India. J Geol Soc India 2010, 75(2), 411-14.

The folds generally initiate at several discrete points along a layer or multilayer undergoing compressional forces. These compressional forces often lead to rotation of fold segments and in all such regimes, folds are strongly asymmetrical and are in complete agreement with the direction in which the force is applied and also with the related thrust sheet movement. This paper illustrates the progressive change in fold geometry with increasing compression and ductile shearing using natural example as studied in the Almora Crystalline Zone (ACZ). The folds in the ACZ have started developing initially by the buckling processes as upright folds with varying degrees of inter-limb angles, which later on with increasing amount of ductile shearing modified in to tight to isoclinal and overturned to recumbent folds.

3 illus, 29 ref

006771   Adham M I;Jahan C S;Mazumder Q H;Hossain M M A;Haque A M (Geology and Mining Dep, Rajshahi Univ, Bangladesh) : Groundwater recharge potentiality of Barind tract, Rajshahi district, Bangladesh using GIS and remote sensing technique. J Geol Soc India 2010, 75(2), 432-8.

The groundwater recharge potentiality in Barind Tract in Rajshahi district, Northwest Bangladesh was studied based on Geographical Information System (G1S) and Remote Sensing technique. In this connection satellite images (Landsat 7 ETM and SPOT) and aerial photos were subjected to several treatment processes using softwares like ERDAS Imagine and ESRI's Arc View. Thus various thematic maps have been prepared for drainage density, lineaments, lithology and land cover/use that allowed deciding their interactive effect. In the present study, the degree of effect was determined for each factor to assess the total groundwater recharge potentiality for two categories (moderate to low). The resultant map shows that 85% of the area has low, and rest has moderate groundwater recharge potentiality. Finally only 8.6% of the total average annual precipitated water (1685 mm) percolates into subsurface and ultimately contributes to recharge the groundwater.

9 illus, 4 tables, 16 ref

006770   Achyuthan H;Thirunavukarasu N (Geology Dep, Anna Univ, Chennai-600 025, Email: hachyuthan@yahoo.com) : Quaternary stratigraphy of the Koratallaiyar-Cooum basin, Chennai. J Geol Soc India 2009, 73(5), 683-96.

Presents Quaternary stratigraphy of the area around Chennai based on archaeological findings on the ferricrete surface, geomorphological observations supplemented by radiocarbon dating. The coastal landscape around Chennai, Tamil Nadu, has preserved ferruginised boulder gravel deposits, ferricretes and fluvial deposits of varying thickness. The area studied is approximately 150 km east to west and 180 km north to south with a broad continental shelf towards the seaward. Several rivers enter the Bay of Bengal along its shores like the Koratallaiyar, Cooum and the Adyar. Precambrian charnockite and Upper Gondwana sandstone and shale bedrock rim the shelf margin. For the most part, the Upper Pleistocene-Holocene fluvial sediments overlie an erosion surface that has cut into older Pleistocene sediments and ferricrete surface. Incised valleys that cut into this erosion surface are up to 5-6 km wide and have a relief of at least 30 m. The largest valley is that cut by the Koratallaiyar River. Holocene sediments deposited in the incised valleys include fluvial gravels, early transgressive channel sands and floodplain silts. Older Pleistocene sediments are deposited before and during the 120-ka high stand (Marine isotope stage 5). They consist of ferricretes and ferricrete gravel formed in nearshore humid environments. Muddy and sandy clastic sediments dated to the ca. 5 ka highstand suggest that the climate was semi arid at this time with less fluvial transport. The coarsening up sequence indicates deposition by high intensity channel processes. Pedogenic mottled, clayey silt unit represents an important tectonic event when the channel was temporarily drained and sediment were sub aerially exposed. Uplift of the region has caused the local rivers to incise into the landscape, forming degradation terraces.

8 illus, 2 tables, 37 ref

005628   Verma S;Mishra A;Gupta S;Agarwal N K (Geology Dep, Lucknow Univ, Lucknow-226 007, Email: senviro@gmail.com) : GIS techniques for evaluating the carrying capacity of the Gomati river basin-a case study of Lucknow urban center. Res Envir Life Sci 2009, 2(2), 67-76.

Geomatic tools have been used as an aid to study the carrying capacity of the Gomati river basin (GRB). The GRB is rich in natural resources, large urbanization, and economic activity. The land use pattern of LUC shows that an area in 1970-1987 was covered 9170.96 while in 2004-05 it was 16270 ha, indicating a 77.4% increase in the total area, while residential use has grown dramatically in comparison to all other uses, although there has also been notable growth in commercial, industrial and public service land use. The rapid increase in population requires more drinking water and transport network. There were 904831 registered vehicles in the year 2007, and 968915 in 2008, which represents annual growth of 7.08 % in the number of registered vehicles. The amount of solid municipal waste, sewage water, air pollutants and noise level has been increased rapidly and reduce the quality of soil, water and air as well as human life. In order to facilitate future planning for the Lucknow urban center therefore, the carrying capacity of GRB is studied with reference of Lucknow urban center resources, i.e. land, water, air, noise and socioeconomic living standards. For this study, digital geographic database of Lucknow urban center is created and analyzed by GIS techniques to examine the carrying capacity of GRB.

005627   Reddy P M (Geology Dep, Dr. B.R. Ambedkar Open Univ, Hyderabad-500 033, Email: pmsrap@rediffmail.com) : Categorization of groundwater quality in Patancheru mandal of Medak district, Andhra Pradesh, India. Res Envir Life Sci 2009, 2(1), 21-24.

Hydrogeochemical investigations, which are significant for the categorization of groundwater quality, have been carriedout in the groundwaters of Patancheru Mandal area of Medak district, Andhra Pradesh, India. 25 groundwater samples were collected from different villages and analyzed to estimate some of the chemical parameters, such as pH, specific electric conductance, total dissolved solids, Cl, SO₄, F and dissolved oxygen. The salinity levels in more than 40% of samples were showing low quality and hence were not suitable for drinking. The chloride and sulphate concentrations in some samples were in medium quality. Even the dissolved oxygen levels in almost all the samples were showing medium quality. It was observed that in the villages where samples were collected the groundwaters were contaminated with one element or other. Granite rocks cover majority of the study area with dolerite dykes and deccan traps in few areas. But the fluoride levels were under suitable condition for drinking. The lithology was not showing similarity with hydrochemistry. However it was noted that the quality was found deteriorated mainly with the industrial activity in the study area.