016319   Rai D C;Singhal V;Bhushan Raj S;Sagar S L (Civil Engineering Dep, Indian Institute of Technology Kanpur, Kanpur-208 016, Email: dcrai@iitk.ac.in) : Performance of residential buildings during the M 7.8 gorkha (Nepal) earthquake of 25 april 2015. Curr Sci 2015, 109(11), 2126-35.

The M 7.8 earthquake of 25 April 2015 was a significant event in the long seismic history of the Eastern Himalayas, which caused more than 8000 casualties and widespread destruction of various structures in the western and central regions of Nepal. This article discusses the general observations in the earthquake affected regions, with special emphasis on the seismic performance of residential structures in the Kathmandu valley region. Widespread damage was observed in unreinforced masonry and reinforced concrete structures in this region which lacked adequate lateral strength and seismic load resisting features. Lack of engineering input was evident from the poor structural configuration of the buildings and non-compliance with the building codes, which aggravated the seismic vulnerability of these structures. Since maximum shaking intensity on Indian side was between V and VI, most structures did escape serious damage, but they continue to remain vulnerable for future design level earthquakes. Despite the knowledge of the high seismicity of the Himalayan region, the present lack of preparedness is unacceptable and it is necessary to implement good earthquake-resistant practices to minimize losses in future earthquakes.

12 illus, 25 ref

016318   Pratheesh P;Prasannakumar V (Geology Dep, Kerala Univ, Kariavattom Campus, Thiruvananthapuram, Kerala, Email: pratheeshponline@gmail.com) : Mafic dykes from the bhavani shear zone: evidences to supra- subduction tectonics in the South Indian granulite terrain. J appl Geochem 2015, 17(3), 352-65.

Bhavani Shear Zone (BSZ) of South Indian Granulite Terrain (SIGT) bears evidences of extensive magmatic activity ranging from acidic to ultramafic intrusives. The dykes belong to two sets (Group I and Group II dykes) with sub-alkaline to calc-alkaline nature and NE-SW or NW-SE trend. Group I belongs to high-Mg tholeiites while most of Group II show a high-Fe tholeiitic nature. Incompatible elements suggest a depleted mantle source for both the Groups and REE distribution indicates considerable fractionation and possible crustal contamination along with probable elemental mobility in the presence of an aqueous solution during high temperature metamorphism. Elemental ratios like K/P, La/Ta and Th/Ta are indicative of probable supra-subduction-mantle source characteristics. Tectonic discriminations imply MORB-CAB-IAT nature for Group I, while Group II dykes show MORB like signatures.

7 illus, 2 tables, 77 ref

016317   Panda S P (Geography Dep, Utkal Univ, Bhubaneswar, Odisha) : Drainage analysis of the baitarani river basin, Odisha. Indian J Landsc Syst ecol Stud 2015, 38(2), 51-60.

Morphometric analysis of the drainage system is an important aspect of characterization of a watershed as all the hydrologic and geomorphic processes occur within the watershed. It is an open physical system in terms of inputs of precipitation and solar radiation, and outputs of discharge, evaporation and re-radiation. Thus, it forms the most fundamental unit of spatial study as the landform in general and the drainage in particular shape the spatial morphometric geometry of a landscape. Various linear and areal aspects of the catchment were computed using GIS environment and manipulated for the different calculations. The analysis has revealed that the total number as well as the total length of segment is maximum in first order streams and decreases as stream order increases. The ' bifurcation ratio between different successive orders is almost constant and its stream length exhibit high degree of positive correlation (0.99) with its number suggesting that there is increase in stream population with respect to increasing stream length and vice versa.

7 illus, 2 tables, 12 ref

016316   Naresh Kumar;Khandelwal D D (NO, Wadia Institute of Himalayan Geology, 33 GMS Road, Dehradun-248 001, Email: nkd@wihg.res.in) : Strong motion data analysis of the 4 April 2011 Western Nepal earthquake (M 5.7) and its implications to the seismic hazard in the central Himalaya. Curr Sci 2015, 109(10), 1821-30.

In the present study, the strong motion data of the 4 April 2011 western Nepal earthquake (M 5.7) recorded by a dense network of 24 strong motion accelerograph stations have been used to estimate horizontal and vertical component of the peak ground acceleration (PGA) to better understand its bearing on the seismic hazard scenario of the Central Himalayan region. We assimilated attenuation curves using the observed PGA values and found that the zone is associated with higher H/V ratio in which the attenuation trend remains bimodal with one trend for closer distance up to 100-120 km, while the other trend corresponds to distances extending beyond 1000 km. We infer that the two different PGA trends have close bearing on the major tectonics and structural set-up of the region, which is possibly attributed to subsurface structural variation through which the seismic wave travels, suggesting changes of crustal heterogeneities beneath the source zone. The present work may improve the concept of ground motion model for evaluating seismic hazard for the Himalaya.

8 illus, 3 tables, 33 ref

016315   Nandy D R (NO, , ) : Tectonic landforms of Northeast India and associated natural hazards. Indian J Landsc Syst ecol Stud 2015, 38(2), 9-31.

Geomorphologically the Northeastern India is the most bewitching part of India presenting contemporary land- forming tectonic processes active since Cretaceous time. Its narrow valley and razor edged high hills, snow clad mountains, meandering rivers, flat high lands (plateau), deep gorges and water falls form fascinating landscapes in a relatively small geographical expanse (fig.l). The world's rainiest spot, Mawsynram, is located here along the southern fault bound scarp face of the Meghalaya Plateau, The narrow and relatively densely populated Brahmaputra valley, the life center of the region, evolved during the last two million years through subsidence and alluviation of the foreland depression in between the young mountain ranges of eastern Himalaya, Mishmi Hills and the Indo-Myanmar mobile belt and the block uplifted plateau of Meghalaya due to the ongoing tectonic process of collision/subduction of the Indian plate. The mighty Brahmaputra River originating from Manas Sarovar of Tibet is one of the most sluggish rivers of the country in the proper valley area creating devastating floods almost every year. The world's largest fresh water river island, Majuli, a stabilized channel bar, occurs in the river Brahmaputra. But the whole river regimen may get changed with the construction gigantic dams across its upper reaches in Tibet. Most of the landforms/landscapes of Northeast India and its adjoining region are geologically very young, developed due to post-collision and active subduction process related tectonic activities of the leading edge of the Indian plate with the Eurasian plate. The said tectonic processes are very active even today making the whole region very unstable that resulted in frequent landslide hazards and floods. The Indian continent is moving at the rate of 18mm per year towards north and 11mm per year to the north-east see the (fig.la).

14 illus, 1 table, 7 ref

016314   Mukhopadhyay S C (Geography Dep, Calcutta Univ, Kolkata-700 019, Email: profscmukhopadhyay_2009@rediffmail.com) : Erosional landforms of parts of the rejuvenated lower Subarnarekha basin, Jharkhand, West Bengal and Odisha. Indian J Landsc Syst ecol Stud 2015, 38(2), 267-82.

This is an attempt of deciphering the polycyclic and poly genetic characters of soils, landforms, environment, drainage patterns (fluvial and Aeolian-combined) autogenic and alogenic changes both in time and space. The author has adopted modern methodology and the advanced techniques including the intensive field work. Special stresses are given on corroded/eroded landforms and the surfaces like thus in the rejuvenated lower Subarnarekha basin India. Along with special attentions are given within from the Domohoni, Jamshedpur downwards-Jharkhand. West Bengal - Odisha States and neighbourhoods.

10 illus, 10 ref

016313   Mondal P D (Geography Dep, Calcutta Univ, Kolkata, West Bengal) : Landslide hazard zonation mapping along transport and arterial sector of Kalimpong sub-division, Darjeeling district, West Bengal. Indian J Landsc Syst ecol Stud 2015, 38(2), 81-91.

Kalimpong Sub-division at Darjeeling Himalaya in West Bengal, India is a place where landslides and related phenomena have became frequent. Recently the incidence of landslide occurrence has increased rapidly with the gradual anthropogenic abuse of slopes specially the development of transport arteries and consequent jerk and vibration by vehicles. Therefore, landslide hazard zonation mapping becomes indispensable to identify the risk zone for future prevention and management of such hazards. With this view in mind the present paper takes an attempt to undertake the work of landslide hazard zonation mapping of Kalimpong Subdivision, Darjeeling district.

5 illus, 4 tables, 14 ref

016312   Mir A R;Alvi S H (Earth Sciences Dep, Kashmir Univ, Srinagar-190 006, Email: mirakhtar.r@gamil.com) : Mafic and ultramafic dykes of singhbhum craton form Chaibasa district, Jharkhand, Eastern India: geochemical constraints for their magma sources. Curr Sci 2015, 109(8), 1399-1403.

17 ref

016311   Meshram T M;Shukla D;Behera K K (NO, Geological Survey of India, Hyderabad-560 068, Email: tusharmeshram1984@gmail.com) : Alkaline lamprophyre (Camptonite) from bayyaram area, NE margin of the eastern dharwar craton, Southern India. Curr Sci 2015, 109(11), 1931-4.

4 illus, 3 tables, 25 ref

016310   Manu Raj R;Kumar S N (Geology Dep, Univ of Kerala, Kariavattom, Email: manuraj1331@gmail.com) : Characterisation of selected sulphides associated with the granitic pegmatites of Nagamalai-Pudukottai area, Madurai district, Tamil Nadu, India.. J appl Geochem 2015, 17(4), 444-50.

The Nagamalai-Pudukottai area, forming part of the Southern Granulite Terrain, is mostly covered by different types of gneisses, quartzite, granites and migmatites. The mineralogical characters and field relations point to the presence of A-type of granites. The granites and gneisses are mainly intruded by two varieties of pegmatites viz., gray-feldspar bearing and pink feldspar bearing pegmatites. The important minerals constituting the gray feldspar pegmatites are feldspars (both white and gray), quartz, biotite, magnetite, calcite and sulphides. The pink feldspar- pegmatites and contain quartz, feldspar, biotite and hornblende as essential minerals and are mostly devoid of sulphide minerals. Sulphides in gray-feldspar pegmatites are seen both in the massive form and as small individual euhedral crystals/crystal aggregates. The massive sulphides which show different colours like whitish gray, brownish yellow and light brown are mostly magnetic. The present study attempts characterization of selected sulphides with the help of XRD and SEM-EDS techniques. Three sulphide samples were subjected to XRD analysis for identification and cell refinement parameters. Of these, the diffraction values of one correspond with pyrite and the other two show a match with pyrrhotite. The pyrrhotite pattern shows excellent agreement with Fe₇S₈ composition. The cell refinement parameters and composition point to the 4C monoclinic character of pyrrhotite. The morphological and chemical study of one pyrrhotite sample, with the help of SEM-EDS analysis, also supports this inference. The monoclinic pyrrhotite is stable only below a temperature of 254°C. The inversion of hexagonal pyrrhotite to monoclinic pyrrhotite is possible by hydrothermal alteration. The association of pyrrhotite with pyrite indicates sulphur richness in the stability field.

7 illus, 2 tables, 23 ref

016309   Manjunatha S;Narasimha P;Ugarkar A G (Geology Dep, Karnatak Science College, Dharwad, Email: manjunarhas29@yahoo.in) : Ore fluids associated with the gold mineralisation in Mangaluru, Karnataka. J appl Geochem 2015, 17(3), 290-5.

Mangalur deposit has two parallel gold bearing zones hosted in the metavolcanic sequence in the south-central part of the Mangalur greenstone belt of Dharwar craton. In these zones, gold mineralization is structurally controlled, hydrothermal epigenetic vein type and is invariably associated with wall rock alterations characterized by ubiquitous presence of pyrrhotite, pyrite, arsenopyrite, chalcopyrite and sphalerite. The gangue minerals are quartz, chlorite, biotite, tremolite and ankerite. Three types of fluid inclusions, namely CO₂ inclusions, H₂O inclusions and H₂O-CO₂ inclusions are recorded in the gold bearing vein quartz of Mangalur gold deposit. H₂O-CO₂ the dominant fluids with low salinity (1.65-7.81 wt% eqv. of NaCl) and low density (0.734-0.878 g/cc) seem to be responsible for gold deposition over a homogenization temperature range of 210 to 240°C.

3 illus, 2 tables, 26 ref

016308   Latha A;Parihar P S;Shiv Kumar K;Nayak S (Atomic Minerals Directorate for Exploration and Research, Begumpet, Hyderabad) : Understanding U-mineralization at Bichun-Nayagaon, Jaipur district, Rajasthan- A petrological approach. J appl Geochem 2015, 17(4), 416-20.

Metasomatite type of uranium mineralization occurs in India along the albitite zone extending from parts of Rajasthan to southern Haryana. Recent Exploration by AMD has established uranium mineralization in Banded Gneissic Complex (BGC) terrain around Bichun-Nayagaon area of Jaipur District, Rajasthan. The host rocks of U-mineralization are characterized as variably albitized granite gneisses and albitites. Albite is the predominant mineral in all these rocks, plagioclase and quartz are the other felsic constituents, with minor K-feldspar. Biotite, hornblende, zircon, apatite and allanite are the accessory minerals. Titano-magnetite, hematite, pyrite, chalcopyrite, bornite, galena, goethite and anatase are the opaque phases. Radioactivity is attributed to davidite, uraninite, U-Ti-Fe complexes, metamict REE mineral, radio-element bearing sphene, adsorbed/labile uranium among various phases. The nature of uranium mineralization and its mode of occurrence suggests that the mineralization has a two phase development, the initial phase of migmatisation followed by later phase of albitization which cumulatively concentrated uranium in these litho-units in this area.

4 illus, 6 tables

016307   Krishnan G;Rao M S;Kumarm S;Garg P K (National Institute of Hydrology, Roorkee, Uttarkhand, Email: drgopal.krishna@gmail.com) : Seasonal variation in the isotopic composition of ground level vapour (GLV)- unraveling monsoon dynamics. J appl Geochem 2015, 17(4), 477-80.

A stronger isotopic depletion in the ground level vapour (GLV) has been noticed in the monsoon period (June -September) during all the years from 2007-2013 at Roorkee, India. GLV received during southwest (SW) monsoon period is always depleted as compared to the GLV received during pre-monsoon (January-May) and post-monsoon period (October-December). Further, it has been found that synoptic weather circulation along with the prevailing local conditions show strong influence on the isotope composition of GLV. The present study provides insight into the atmospheric dynamics, though long term data is required to verify the philosophy and results of the paper.

3 illus, 18 ref

016306   Gusain H S;Manish Kala;Ganju A;Mishra V D; Snehmani (Research and Development Centre, Chandigarh-160 036gusain_hs@yahoo.co., , ) : Observations of snow-meteorological parameters in Gangotri glacier region. Curr Sci 2015, 109(11), 2116-20.

In this communication analysis of the snow-meteorological parameters recorded in the Gangotri glacier region has been presented. Maximum temperature, minimum temperature, snowfall, snow cover thickness, incoming shortwave radiation flux, reflected shortwave radiation flux and albedo have been recorded at 'Bhojbasa' observation station. Meteorological data of 13 years from 2000 to 2012 have been presented for annual and seasonal variations in temperature, snowfall and snow cover thickness. Winter, premonsoon, monsoon and post-monsoon data have been considered for analysis. Annual mean maximum and minimum temperature are 11.1 ± 0.7°C and -2.3 ± 0.4°C respectively. Mean values of these parameters obtained for winter season are 3.0 ± 1.0°C and -10.4 ± 1.3°C respectively. Mean annual snowfall amount is 257.5 ± 81.6 cm and maximum snow cover thickness varies from 42 to 205 cm for different years. Incoming shortwave radiation flux and reflected shortwave radiation flux have been recorded using pyranometer sensor mounted on automatic weather station, and data for 2012 and 2013 are presented. Incoming shortwave radiation flux and total atmospheric transmissivity have been estimated. Mean annual atmospheric transmissivity is 0.37 at the observation location. Mean seasonal albedo for winter season is observed to be quite high compared to other seasons. Maximum and minimum temperature reveal an increase of 0.9°C and 0.05°C respectively, during the decade. Annual snowfall amount reveals a decrease of 37 cm in the decade. The observed temperature and snowfall patterns during the past 13 years, at the present study location, indicate that trends in Central Himalaya may be in accordance with the observed trends in the Western Himalaya.

5 illus

016305   Gopalan K (NO, CSIR-National Geophysical Research Institute, Hyderabad, Email: gopalank1@rediffmail.com) : Natural radioactivity and geochraonometry: an overview. J appl Geochem 2015, 17(3), 266-89.

Radiogenic isotope data generated and published by specialists are meant for serious students and active workers in radiogenic isotope geochronology and geochemistry. Even books on the subject are generally addressed to the same audience. As such data bear increasingly on many other areas of earth science, there is a great need for a concise and clear overview of the basic concepts and principles of isotopic dating (geochronometry) rather than facts (geochronology) to help non-specialist students and researchers gain an intelligent understanding of radiogenic isotope literature. This overview aims to fill this need, and assumes only college level knowledge of physics, chemistry and mathematics. A review of fundamentals in a mature field cannot be very original in its contents, but considerable effort has been made to unify and generalize the essential information in a new and original way.

14 illus, 2 tables, 43 ref

016304   Gokula A P;Sastry R G (Earth Sciences Dep, Indian Institute of Technology, Roorkee-247 667) : Gravitational attraction of a vedrtical pyramid model of flat top and bottom with depth-wise linear density variation. Curr Sci 2015, 109(10), 1870-75.

In 3D gravity modelling, a right rectangular parallelepiped with either constant density or variable density functions in spatial and spectral domains enjoys wide popularity. However, better unit models are needed to meet the large variety of geological scenarios. Here, we present an analytical expression for the gravity effect of a vertical pyramid model with depthwise linear density variation. Initially, we validate our analytic expression against the gravity effect of a right rectangular parallelepiped and provide two synthetic examples and a case study for illustrating the effectiveness of our pyramid model in gravity modelling. The included case study of Los Angeles basin, California, USA, demonstrates the comparative advantages of our pyramid model over the conventional right rectangular vertical prism model. Thus, our pyramid model could be quiet effective as a building block for evaluating the gravity effect of an arbitrarily-shaped 3D or 2.5D source(s).

5 illus, 1 table, 8 ref

016303   Das S K;Routh J;Roychoudhury A N (Geology Dep, Presidency Univ, 86/1 College Street, Kolkata700 073, Email: sdas.geol@presiuniv.ac.in) : Biogeochemsitry of shallow lake sediments: a case study from verlorenvlei, South Africa. Curr Sci 2015, 109(8), 1486-91.

Studying the biogeochemistry of shallow lake sediments, especially the source of sedimentary organic matter (OM), is challenging because of the low preservation of OM in shallow lake sediments. Here we report the source of sedimentary OM in a shallow freshwater lake, Verlorenvlei, in South Africa using a number of biogeochemical proxies. Elemental carbon and nitrogen ratio (C/N), and stable C and N isotopes (δ^{13C and δ15N) indicate algal source of the sedimentary OM. Total organic and inorganic C, different phosphorus fractions, δ13C and δ15N values indicate repetitive presence of non-N-fixing cyanobacteria under moderate N-limited conditions. Cyanobacterial population in Verlorenvlei is likely influenced by the availability of dissolved inorganic C. Cyanobacterial proliferation in the lake has ceased with accelerated N input as recorded at the top of the core.}

3 illus, 1 table, 47 ref

016302   Das C (Geography Dep, S.S. Jalan Girls College, Kolkata) : Meandering course of medinipur upland rivers. Indian J Landsc Syst ecol Stud 2015, 38(2), 65-71.

In this paper analysis of the wavy nature of the rivers and streams flowing in the study area of the Upland of Western Medinipur has been attempted. The area has two rivers Dulung and Taraphini with their full course in the study area. Two main rivers the Kangsabati and Subamarekha have apart of their course within the area. The Subarnarekha has a small section in the south western part while the Kangsabati has a longer run in the area. The analysis is based on Mutter system of Sinuosity Index. The toposheet 1:50,000 has been used, beside on the spot field study at some points The criteria for meandering has been taken to be Sinuosity Index value of greater than 1.5 as suggested by Morisawa and other authors.

8 illus, 1 table

016301   Chttopadhyaya A (North-Eastern Hill Univ, Central Univ with UPE, Meghalaya) : Wave refraction determines inland exuviation over time: A GIS based approach towards the coastal blocks of Purba Medinipur district, West Bengal. Indian J Landsc Syst ecol Stud 2015, 38(2), 203-9.

Beach erosion is a problem in many maritime countries and tackling of beach erosion problems is a real tricky job. The main problem has arised in Bay of Bengal coast particularly in Purba Medinipur coastal regime is due to the change of convergent wave in to divergent one. Changes in way, direction and magnitude of wave has changed all the interrelated geo-environmental systems over time. Changes in underwater topography causes wave refraction which is linked with beach erosion of Digha and its surrounding regions. Drainage channels namely Peechaboni Khal, Munder Mohona, Digha Khal etc. has been contributed in carrying silt and sand into the sea with their discharges. Advanced statistical techniques and methodologies are adopted to analyze the impact of wave refraction on coastal landscape. Therefore, an attempt has been made to find out how inland exuviations have been determined by wave refraction.

5 illus, 9 ref

016300   Biswas S (NO, , Geography Dep, Calcutta Univ) : Shifting of river Bhagirathi and its impact on land use of Nadia and Burdwan district with special reference to Jaluidanga Mouza. Indian J Landsc Syst ecol Stud 2015, 38(2), 190-7.

Holy Ganga, the most precious river with its spiritual value, continues its long journey through the northern parts of the country. Through its eastward journey, it enters West Bengal, one of the states of Eastern India at Rajmahal and covers 207kms before leaving the state at Jalangi. Throughout the snaky-path channel shifting is a common phenomenon generally observed in its flood plain areas. The present paper is concerned with analysis of hydro geomorphic causes of channel shifting of Bhagirathi River and its impact on land resources of Burdwan and Nadia district, West Bengal. The study area extends from 2301631" N to 23022'44"N latitude and 88018'15" E to 88023'15" E longitude. Analyzing the satellite imagary and topographical map (SOI) of the Bhagirathi river in Nadia and Burdwan districts through the year of 1922,1968 and 2011, it is found that, there is distinct channel shifting of Bhagirathi river towards its left bank which is administratively in Nadia district. The right bank of the river is part of Burdwan district. Stream energy, Geo- lithologic characteristics, Geomorphologic characteristics, Climatic condition, Channel configuration, Sedimentation and Bank stratification are the major controlling factors of channel shifting of Bhagirathi River in this area. Sarupganje, Setkhali, Baraganje, Nasaratpur, Jaluidangai Samudragar, Hatipota, Mathrapur, Maltipur are mostly affected due to bank failure. The river has been shifting 15 to 20 meters in every year.

15 illus, 1 table, 12 ref

016299   Banerjee S;Matin A;Muku M (Geology Dep, Calcutta Univ, Kolkata-700 019, Email: sdbanj87@gmail.com) : Overburden-induced flattening structure in the Himalaya: mechanism and implication. Curr Sci 2015, 109(10), 1814-21.

Small-scale structures in fold-thrust belt are mainly formed in response to the emplacement of thrust sheets. However, some small-scale structures may not be developed directly in response to the emplacement of thrust sheets, but might be genetically tied with the orogenic process. Metre- to centimetre-scale late-stage folds on foliation in phyllite with near-recumbent fold geometry are selectively developed with a specific spatial distribution, particularly in places where the foliation is steeply dipping, in the Ramgarh thrust sheet in the Darjiling-Sikkim Himalaya. The recumbent-fold structures appear to have been formed in response to overburden-induced vertical compressive deformation on steep dipping foliation, especially in the subvertical southern limb of the antiformal structure of the Lesser Himalayan Duplex in the Darjiling-Sikkim Himalaya. The role of gravity and overburden in the formation of these structures from worldwide orogenic belts may be considered to validate their genesis.

6 illus, 51 ref

016298   Ankana;Mishra K;Mishra S P (Geography Dep, Banaras Hindu Univ, Varanasi) : Morphometric analysis in watershed development in Chakia tehsil, district Chandauli, Uttar Pradesh. Indian J Landsc Syst ecol Stud 2015, 38(2), 33-42.

Morphometrc parameters are very significant variables in watershed development that present inevitable conditions for planning natural resources and ultimately regional development. This approach has gained more momentum after the advancement in space technology and data reception and analysis techniques. Remote Sensing and GIS together are fulfilling the required database for watershed developmental and planning. The present paper attempts to analyze the various aspects of drainage morphometry and development priority assessment of watersheds. Ranking score method has been adopted to assess the priority status of different watersheds based on their morphometric parameters and the result has been summarized as high, medium and low priority orders that may be considered for development planning.

2 tables, 38 ref

015157   Tripathi S K;Resmi S;Roychaudhary S; Karthikeyan M;Meitei S I;Pradhan R K (Operation East Coast-I, Marine and Coastal Survey Div, Geological Survey of India, Kolkata-700 091, Email: stripati208@gmail.com) : Pyrite framboids from buried paleo estuary off Chilka lake, Odisha. Indian J Geosci 2015, 69(2), 145-54.

Framboidal pyrite from core sediment off Chilka Lake has been studied in detail using scanning electron microscope (SEM) and energy dispersive X-ray analyser system (EDX). Study indicates that framboidal pyrite forms in the cavities, tests of degraded organic remains and other entities under reducing condition, where it occurs mostly in clusters. EDX analysis indicates that oxygen, iron and sulphur are the main constituents of framboids. Presence of rod-shaped bacteria on Triloculina test and bacterial colonies over the crystal phases even after the formation of framboids suggest biogenic origin. Clustered framboids are mainly euhedral, octahedral as well as anhedral grains (mostly <62> 12-15 μm and others <60> 5 μm in size) suggesting both syngenetic and diagenetic pyritization facilitated by the decay of organic matter off paleo estuary. So the overall formation of pyrite framboids indicates organic sulphur formed as a result of bacterial action under euxinic to dysoxic or oxic environments. Moreover, presence of foraminifers like Ammonia tepida, Elphidium advenum and Quinqueloculina seminulum along with organic matter and framboids supports estuarine environment.

5 illus, 58 ref

015156   Sitender;Rajeshwari (Geography Dep, Kurukshetra Univ, Haryana, Email: rajeshwariku@gmail.com) : Identification of suitable sites for artificial recharge in Mewat district, Haryana. Trans Inst Indian Geogr 2015, 37(2), 245-57.

Aquifer replenishment through artificial recharge has become necessary to sustain groundwater resources in arid and semi-arid regions to alleviate the problem of continuous declining of water table. In this context, present study deals with the delineation of artificial recharge zones as well as the identification of favorable recharge sites using remote sensing, geographic information system and multi-criteria decision making technique for augmenting the groundwater resources in Mewat district of Haryana, India. For the purpose, thematic layers are prepared : These layers are prepared using Landsat ETM satellite imagery, Survey of India's toposheets, district resource maps by Geological Survey of India and other collateral data collected from different agencies and departments. Thematic layers and their corresponding features have been assigned weight on a scale of 1 to 9 respectively based on their relative contribution to groundwater recharge. Normalized weights are computed using pair-wise comparison matrix of Satty's analytical hierarchy process. All thematic layers are then integrated in the GIS environment using raster calculator tool to prepare a composite map representing artificial recharge zones in the study area. On the basis of the resulted map, study area is classified into three potential recharge zones namely; highly favorable, moderately favorable and least favorable. Intersection points of lineaments with streams of second and third order are considered as possible recharge sites. Results of this study could be very effective in the formulation of sustainable and efficient groundwater management plan of Mewat district.

5 illus, 3 tables, 18 ref

015155   Sinha D D;Mohapatra S N;Pani G P (Centre of Remote Sensing & GIS, SOS in Earth Science, Jiwaji Univ, Gwalior) : Site selection for suitable water harvesting structure using remote sensing and gis. Trans Inst Indian Geogr 2015, 37(2), 223-34.

Site selection for suitable water harvesting structures using modern techniques such as remote sensing and GIS has become inevitable for any water resources development planning work. In the present work suitable sites have been demarcated to develop a water resources development plan in Bilrai watershed of Shivpuri district Madhya Pradesh using geospatial techniques. The Indian remote sensing satellite data along with other collateral data sets and other existing maps have been utilized to extract information of various features such as lithological, geomorphological, structural, drainage, slope, land use/land cover and soil. These thematic maps have been generated using ARC GIS and ERDAS Imagine software. DEM has been generated from contours in order to obtain the slope percentage and slope aspect of the area. The major geomorphic units are alluvial plain, pediplain, valley fill, linear ridge, denudational hill and structural hill. Groundwater potential zones were delineated by weighted overlay analysis. As far as the groundwater potential zones are concerned 62.4 5% of the area falls in zones of good and very good category, where as the very poor, poor, and moderate category accounts for 37.55%. These are the areas of concern for further development in terms of ground water prospects. Finally a map showing suitable sites for the water harvesting structures has been prepared based on the IMSD criteria. The major water conservation structures recommended for the area are nala bunds, check dams, gabions and drought ponds. On the basis of the result obtained it was concluded that the water availability of the area is mainly controlled by topography, geology and geomorphology. Remote sensing and GIS technology can be efficiently used to develop water resources development plan of semi arid regions of Shivpuri district, Madhya Pradesh.

4 illus, 2 tables, 23 ref

015154   Sharma K;Jalan S (Geography Dep, Rajasthan Univ, Jaipur, Email: kavitasharma2712@gmail.com) : Spatio-Temporal assessment of land use/land cover changes in Jaipur city using satellite data. Trans Inst Indian Geogr 2015, 37(2), 269-80.

Land use and land cover is an important manifestation of man-environment interactions and thus, for understanding this inter-relationship, simulation of contingent changes assumes great significance. This paper attempts to study the land use and land cover changes in Jaipur city, the fast growing capital of Rajasthan State, over a decade from year 2000 to 2011. Remote Sensing and Geographical Information System have been employed to identify, delineate and quantify the changes. Thematic maps have been prepared using LANDSAT imageries of May 2000 and May 2011 and changes in land use/ land cover have been identified through post classification change detection. Accuracy of classification has been verified using ground truth sample observations. Results reveal that urbanization has taken a toll on green area in the city region. Total agricultural area which occupied about 35.07 percent of the city area in 2000 has reduced to 31.03% in 2011. Vegetation has also undergone negative change. Total Built-up land has notably increased by approximately 10% from 31.95% to 41.91% of the total area. Results underline the pressing need for proper land use planning for sustainable development of Jaipur city to meet the challenges posed by rapid urbanization.

8 illus, 8 ref

015153   Samanta S K;Majumdar R K;Chowdhury S (Geological Sciences Dep, Jadavpur Univ, Kolkata-700 032, Email: ranjit_mazumdar2000@yahoo.co.in) : Modes of slope failure in layered rocks of landslide zones: insight from finite element modelling. Indian J Geosci 2015, 69(2), 117-30.

Present work aims at determining the geometry of slip surface and the modes of slope failure in natural layered or foliated rock system in landslide-prone areas. Simulations are carried out to evaluate plastic deformation in layered anisotropic slope medium under gravitational force. Using ANSYS (ver. 10), the equivalent plastic strain is contoured considering Drucker-Prager yield criterion. Mechanical layer anisotropy is simulated by alternate (thick) strong and extremely (thin) weak layers. The stability analysis is performed in layered anisotropic slope medium considering four factors: 1) degree of anisotropy in the terms of thickness ratio of strong layers to weak layers - 60:1 and 40:1; 2) orientation of the anisotropic planes with respect to the slope - opposite i.e. anaclinal slope (Type I) and same i.e. cataclinal slope (Type II); 3) inclination of anisotropic layers - 75°, 60°, 45°, 30° and 15°; and 4) slope angle - 75°, 60°, 45° and 30°. Slope failure in layered rock medium occurs in two primary modes. They are: Mode 1 i.e. block movement or rock fall; Mode 2 i.e. rock slide. Mode 2 can be subdivided into two categories. Mode 2A involves sliding along newly developed curved slip surface and Mode 2B involves sliding along thin weak layers. The study reveals that: 1) Anaclinal models with layers dipping in opposite direction (Type I) are usually more stable than the cataclinal models with layers dipping in same direction (Type II), 2) In layered medium, presence of thin weak layers may, in some specific situations, reduce the chalices of slope failure with respect to the isotropic model by accommodating the plastic strain, 3) There is no such direct relation between the types of model and modes of failure. Mode 1 failure is very rarely found. It takes place either along the very short new failure surface at the bottom of Type I model, or along the small active weak layers at the top of slope of Type II model. Type I and Type II models both may fail along the newly developed curved sliding surface following Mode 2A in specific situations. But, Type II model fails mainly by sliding along thin weak layers following Mode 2B if the layer inclinations are lesser than the slope angle.

7 illus, 33 ref

015152   Roychowdhury M (Marine Science Dep, Calcutta Univ, 35, B.C. Road, Kolkata) : Effect of salinity on the above-ground biomass and growth of dominant mangrove plants in Indian Sundarbans. Ann Biol Res 2015, 6(5), 20-5.

Depending on the geographic locale of the Indian Sundarbans was diversified in terms of salinity which directly reduced the growth of mangrove vegetation. Above-ground biomass estimation was carried out for five even-aged dominant mangrove species (Sonneratia apetala, Excoecaria agallocha, Avicennia alba, Avicennia officinalis and Avicennia marina) in western and central sectors of Indian Sundarbans during 2011 to 2013. Among the selected species, A. marina (60.15 t ha^{-1) showed maximum above-ground biomass in western sector followed by A. officinalis (55.88 t ha-1), S. apetala (52.85 t ha-1), A. alba (51.55 t ha-1) and E. agallocha (26.41 t ha-1). In central sector, the maximum above-ground biomass was observed in A. marina (49.74 t ha-1) followed by A. officinalis (44.46 t ha-1), S. apetala (42.52 t ha-1), A. alba (36.96 t ha-1), and E. agallocha (17.94 t ha-1). The growth was more in the species of western Indian Sundarbans compared to the central Indian Sundarbans. The relatively higher values of AGB in the western sector compared to the central sector are reflections of salinity.}

3 illus, 4 tables, 32 ref

015151   Ranjan S K;Pal S K;Singh K K K (Applied Geophysics Dep, Indian School of Mines, Dhanbad-826 004, Email: ssanjitism@gmail.com) : Approach to improve shallow surface investigation using joint analysis of rayleigh and love waves. Curr Sci 2015, 109(7), 1239-42.

4 illus, 1 table, 18 ref

015150   Raffic M;Raghubanshi B P S;Chauhan S V S; Mishra R;Dubey S K;Singh Y P (NO, RVSKVV, Gwalior, Madhya Pradesh) : Status of potassium fractions in Morena district of Madhya Pradesh. TECHNOFAME 2015, 4(2), 16-21.

Over all 150 surface soil samples (0-15 cm) were collected from 15 different villages (10 soil sample/ village) of five Blocks, namely Morena, Ambah, Porsa, Joura and Kailaras of Morena district of M.P during the year 2011-12. From each block 25 sites were selected for sampling. Results indicated that the amount of water soluble, exchangeable and nonexchangeable, lattice and total -K of Morena district: ranged from 4.2 - 19.2, 34.0-186.0, 291.3-1628.1 with the mean value of 9.6, 101.1 and 820.0 mg kg^{-1 respectively. The amount of lattice and total-K of Morena district; ranged from 0.42-1.95 and 0.45-2.11% with the mean value of 1.08 and 1.17%, respectively. Electrical conductivity of soil showed negative relationship with all the forms of potassium but they are not reaching the level of significant. In general, organic carbon content of the soils of showed positive relationship with all the forms of potassium. The coefficient of correlation of organic carbon with water soluble, (r= 0.586**), exchangeable (r= 0.615**), non-exchangeable -K (r=0.579**), lattice -K (r=0.482**) and total K (r=0.500**) were observed which were significant at higher level (1%). Highly significant and negative correlations were observed between different forms of potassium and sand particles content of the soils. In general, clay particles of the soil showed positively and significantly relationships with all the forms of potassium. A highly significant (1% level) and positive relationships were observed between different forms of K, these relationship indicated that there existed an equilibrium between these forms of K and depletion of one is instantly replenished by one or more of the other forms of K.}

4 tables, 12 ref

015149   Patra P;Devi R;Bawana (NO, Aditi Mahavidyalaya (Univ of Delhi), Bawana, Delhi-110 039, Email: roshaniberi@gmail.com) : Landslide hazard assessment and mitigation strategy in the Himachal Pradesh. Trans Inst Indian Geogr 2015, 37(2), 235-43.

Landslides are destructive geological processes which not only degrade lands in hilly areas but also cause deaths and destruction to property worth billion dollars. The problem of landslide is common and frequent in Himachal Pradesh. The spatial distribution of landslide in the study region shows linear patterns, viz. along roads, rivers or lineaments/ faults. Besides, heavy rainfall, floods and earthquakes enhance the vulnerability condition. The landslides may be part and parcel of the Himalayan landscape, but they can be mitigated by some suitable measures. Few methods of landslide prevention in the sample location have been suggested.

3 illus, 1 table, 8 ref

015148   Patnaik S K;Patra S C (Geography Dep, Rajiv Gandhi Univ, Itanagar, Arunachal Pradesh) : Interventions on watershed management programme in wetlands of Jaysagar for fishery purposes. Trans Inst Indian Geogr 2015, 37(2), 291-300.

Assam, India has around 43433.50 ha of swampy area constituting 0.55% of the total geographical wherein watershed management programme can be a boon in augmenting the economic condition of the native people. Jaysagar wet land area covering an area of 237hectares and depth of water varying up to three meter i.e. from 67m to 70 m amsl of Nagaon district in Assam is taken as a site for present study. Only few entrepreneurs or SHGs are engaged in fisheries with one pond. Production ranges from 500 kg to 1200 kg per pond per annum and results in an income of about INR25000 to INR50000. The wetland also has wet rice cultivated area, used for sustenance. This multi faceted study reveals there is a potential to up-scale the success of minor fishery ponds into well developed fishery tanks in this swamp area coupled with agricultural practices. As the seasonally alternating economic activities of fishing and cultivation are the mainstay of the people of the area, understanding of the wetland resources and services will further help in augmenting the economy of the dependent households through aquatic resources management and community based ecological management of this fast encroached Jaysagar.

2 illus, 2 tables, 26 ref

015147   Pal S;Shrivastava J P;Mukhopadhyay S K (Geology Dep, Delhi Univ, Delhi-110 007, Email: jpshrivastava.du@gmail.com ) : Polycyclic aromatic hydrocarbon compound excursions and K/Pg transition in the late cretaceous-early palaeogene succession of the um sohryngkew river section, Meghalaya. Curr Sci 2015, 109(6), 1140-50.

A combustion-derived polycyclic aromatic hydrocarbon (PAH) compounds based high-resolution stratigraphic records across the Cretaceous/Palaeogene boundary section of the Um Sohryngkew river section is presented in this paper. The yellowish brown, organic-rich, 1 to 2 mm thick, clay layer in biozone CF3 is marked by sudden increase in the high molecular weight fluoranthene, pyrene, chrysene, benzo(a) anthracene PAH compounds. These componds are similar to those associated with the well-known K/Pg boundary sections across the world. Besides these, high abundance of low molecular weight 3 ring anthracene and fluorine, and 4 ring PAH compounds is also noticed in this layer. Subordinate amount of low molecular weight 3-ring phenanthrene, 3-methylphenanthrene, 2-methylphenanthrene, 9-methylphenanthrene and 1-methylphenanthrene PAH compounds have also been found in the successive layer of biozone CF2. Occurrence of high molecular weight PAH compounds in the biozone CF3 (66.83-65.45 Ma age) imply global fire, induced by the heat supplied by Abor/ Deccan volcanic activity, possibly linked with the K/Pg boundary transition events as later initiated prior to the K/Pg boundary, however, the main episode of Deccan volcanic activity occurred <126>300 ky earlier or at the K/Pg boundary itself. PAH compound anomalies in the biozone CF3 is well coinciding with the well documented Ce anomaly layer, but, preceded by planktonic foraminiferal break and PGE anomaly bearing layer in the biozone P0. It is inferred that the K/Pg boundary related global fire played significant role in the collapse of the ecosystem, causing sudden demise of organisms.

6 illus, 1 table, 40 ref

015146   Mogalekar H S;Jawahar P;Francis T;Sujathkumar N V;Karal Marx K;Canciyal J;Pavinkumar P (Fisheries Biology and Resource Management Dep, Fisheries College and Research Institute, Tamil Nadu Fisheries Univ, Thoothukudi-628 008, Email: mogalekar.hs10@gmail.com) : Impact of river linking on aquatic ecosystems. J Aquacult Trop 2015, 30(3-4), 247-56.

Present paper overviews potential implications of the proposed river linking project on aquatic ecosystems. River linking might have positive as well as negative impacts on aquatic ecosystems, such as water quality changes, loss of habitat, alteration in spawning and breeding grounds, effect on fish migration, changes in land-ocean interactions, effect on fish ecology and biodiversity, impact of inland navigation and/or effect on fish production. Successful completion of the river linking project could result balanced distribution of water and increase agriculture/aquaculture production and generate employment. However, visualizing many relevant issues of the sustainable aquatic biodiversity conservation is also important. There is need of case specific studies, citing the example of the Western Ghats, Himalaya and Eastern Ghats which is known for its unique flora and fauna, and implementation of such construction-intensive project will lead to biodiversity loss that would be beyond comprehension.

1 illus, 27 ref

015145   Mankar R S;Srivastava A K (Geology P.G. Dep, SGB Amravati Univ, Amravati-444 602, Email: ashokmt2000@hotmail.com) : Salbardi-belkher inland basin: a new site of lameta sedimentation at the border of districts Amravati, Maharashtra and Betul, Madhya Pradesh, Central India. Curr Sci 2015, 109(7), 1337-44.

The Late Cretaceous infratrappean Lameta sediments in central and western India are known from five inland basins, viz. (i) Nand-Dongargaon, (ii) Jabalpur, (iii) Balasinor-Jhabua, (iv) Ambikapur-Amarkantak and (v) Sagar. Among these, the successions in the first three basins are well studied. The dinosaurian remains from the formations of these inland basins serve as a significant tool for regional reconstructions of palaeogeographic and palaeoenvironmental conditions during Lameta sedimentation. Here, a new inland basin with good outcrops of Lameta sediments having dinosaurian skeletal remains egg nests and eggs is documented. Considering the lithofacies and dinosaurian remains from this new inland basin, it is evident that Lameta sedimentation during the Late Cretaceous was not restricted to only five inland basins documented earlier, but was taking place contemporaneously in an additional inland basin in between Balasinor-Jhabua in the west and Nand-Dongargaon basin in the east. We propose the name of this new site as Salbardi-Belkher inland basin. This newly identified basin lying at the border of Maharashtra and Madhya Pradesh also redefines the existing palaeogeographic limits of Lameta sedimentation, including dinosaur inhabitation.

3 illus, 1 table, 44 ref

015144   Lohe S;Rawat M S;Nagaland L (Geography Dep, Kohima Science College, Jotsoma, Nagaland, Email: sakhoveyi_1@yahoo.com) : Land and water resources degradation in Phek district, Nagaland. Trans Inst Indian Geogr 2015, 37(2), 213-21.

Land and water are the two most vital natural resources that provide the most basic needs of mankind. But these two most vital resources are degrading at an alarming rate due to various activities. It is estimated that over 70% of soil depletion, degradation of land and deterioration of water resources in Nagaland are attributed to the practice of shifting cultivation, without proper conservation measures. In addition, natural factors like hilly terrain coupled with heavy rainfall in the state cause soil erosion through runoff water resulting in low food grain production. As such, the farmers continue to remain the poorest of the poor among the society. As land and water resources are limited, it is absolutely necessary that sustainable and scientific management practices are adopted and applied without imparting the ecological and environmental status.

2 illus, 3 tables, 9 ref

015143   Karlekar S (Earth Sciences and Dean, Faculty of Moral, Social and Earth Sciences, Tilak Maharashtra Vidyapeeth, Pune, Email: shrikantkarlekar18@gmail.com) : Beach response to natural headlands on South Konkan and Goa coast. Trans Inst Indian Geogr 2015, 37(2), 201-9.

Coastline of Konkan and Goa is characterized by innumerable pocket sandy beaches. Many of these beaches are log spiral and parabolic in shape and are headland controlled embayed beaches. The shapes produced as natural equilibrium shapes suggest their response to headlands and bays and the pattern of refraction and diffraction of waves approaching the shore. An attempt is made in this paper to investigate beaches from South Konkan and Goa to understand their response to natural headlands in terms of their shape and stability as a function of distance between headlands bounding the embayment, wave obliquity, and site specific shoreline configuration. The equilibrium shoreline form of crenulated or headland-bay beaches is widely accepted by coastal geomorphologists and engineers. In this paper an account of 26 beaches from South Konkan sector of Maharashtra and 8 beaches from adjoining coast of Goa is given to understand their response to bounding headlands resulting in log spiral and parabolic shapes.

4 illus, 10 tables

015142   Gedam R K;Vinoda N K;Misra R K;Khangar R G (Geophysics Div, Geological Survey of India, Central Region, Seminary Hills, Nagpur-440 006, Email: r.gedam@gsi.gov.in) : Geophysical study to delineate the extension of Gondwana in the Northwestern part of Wardha valley coalfield, Yavatmal district, Maharashtra. Indian J Geosci 2015, 69(2), 155-68.

Geophysical surveys employing gravity, magnetic (TF) and limited deep electrical resistivity sounding (DES) were carried out in the area falling in Survey of India (SoI) topographic map 56 I/13 with an objective to delineate the extension of Gondwana below Deccan traps. The area is bounded by latitudes 19°50'04" and 20°00'54" N and longitudes 78°45' and 78°55' E and forms part of Wani Tahsil of Yavatmal District, Maharashtra. A total of 200 km^{2 area was covered involving 170 gravity-magnetic observations and 7 deep electrical resistivity soundings. The gravity and magnetic surveys were carried out along available roads, tracks, etc. The DES surveys were carried out at selected locations by using Schlumberger array with maximum electrode spread (AB) of 3600 m. It appears that the low gravity anomaly in the centre of the area indicates an elliptical-shaped basin/graben structure below the Deccan trap. The margins of the basin are faulted. A swing of contours towards south in the southwestern part and their alignment in east-west direction indicates a sub-basinal structure in this part. The gravity gradient at the northeastern margin is steeper than the gradient observed in the southwestern part. This indicates a fault at the northeastern margin and a contact /fault at the southwestern margin of the basin. The basin is filled with low-density sediments of Motur Formation (Gondwana) below Deccan traps and assumes importance as coal mines are located in Khumbharkhani which is situated in the northeastern part of the basin. The magnetic (TF) contour map shows sporadic nature of bipolar anomalies in the western part, which may be due to variation in thickness /concentration of magnetic material in the basalt. Deep electrical resistivity soundings have been able to determine thickness of traps and depth to bedrock at few locations. DES survey has also confirmed a fault at the northeastern part of the basin and a contact at southwestern margin of the basin.}

6 illus, 2 tables, 13 ref

015141   Fatoba J O;Olorunfemi M O;Eluwole A B (Geophysics Dep, Federal Univ, Oye, Oye-Ekiti, Ekiti State, Nigeria) : Subsurface structures and the effect on flexible pavement performance: the shagamu-Benin expressway, Southwestern Nigeria, as case study. Indian J Geosci 2015, 69(2), 137-44.

Geoelectric and electromagnetic surveys were conducted on failed highway pavement segments at Ilisan and Ore localities along Shagamu-Benin expressway. The objective was to determine the causes of perpetual pavement failure along segments of the highway which have always defied rehabilitation. Twenty Schlumberger Vertical Electrical Soundings (VES) were carried out with electrode spacing (AB/2) varying from 1 m to 75 m and a total spread of 150 m. The VES data are presented as sounding curves and interpreted by partial curve-matching technique and computer-assisted 1-D forward modelling. The results of VES are presented as geoelectric sections. Two-dimentional resistivity imaging using dipole-dipole array with electrode spacing (a) = 5 m and expansion factor n = 1 - 5 was conducted along the road segments and along the same profile with the VES. The 2D resistivity imaging data were inverted using the Dipro software. VLF-EM inline profiling with station interval of 5 m was carried out to confirm the geologic features depicted by the VES and 2D resistivity imaging. The VLF-EM results are presented as profiles. The geoelectric sections identified: a) lateritic sand having resistivity of 1230 ohm-m and an average thickness of about 2.2 m as the subgrade materials at Ilisan locality and b) partly weathered basement with resistivity ranging from 283 ohm-m to 7848 ohm-m as the subgrade materials at Ore locality. The subgrade materials at both the localities are adjudged competent to sustain the stability of the highway pavement. However, the 2D resistivity imaging and VLF-EM identified low-resistivity zones (<60> ohm-m), which are diagnostic of the presence of buried stream channel and shear zone respectively, beneath the subgrade materials at Ilisan and Ore localities respectively. These features may have been responsible for the flexible pavement failure always experienced at the investigated highway segments.

4 illus, 13 ref

015140   Dutta P K;Acharyya S K;Jha N;Khangar R; Khasdeo L;Mishra K G;Ramanamurty B V (NO, Indian State Univ, Terre Haute, IN 47809, USA) : Resolving kamthi-related problems in Gondwana stratigraphy of Penisular India. Indian J Geosci 2015, 69(2), 85-102.

Debate on the Gondwana stratigraphy in the Pranhita-Godavari and Johilla valley basins against that of Damodar Valley and many other Gondwana basins is persisting for more than a century. The intra-cratonic Gondwana basins host early Permian to early-mid Jurassic sediments. The Gondwana lithostratigraphic units can be structured broadly around a composite sequence of four representative lithostratigraphic units, like the glaciogene Talchir, the carbonaceous shale and coal-bearing Damuda, the feldspathic sandstone and red-mudstone bearing the Panchet, and the hill-forming, feldspar-poor, quartzarenite and variegated claystone bearing the Supra-Panchet. These lithostratigraphic units are referred to here as units A through D. On the other hand, the unit known as the 'Kamthi formation' has late Permian to early Jurassic dual and mixed- up bio- and lithostratigraphic levels. Each of these lithostratigraphic units corresponds to formation or group rank. These Gondwana sediments derived from granitic source were deposited largely in fluvial basins involved in block-faulted half grabens. The sedimentation coincided with the global climatic cycle as it was changing from an icehouse state in the Late Paleozoic to a greenhouse state in the Mesozoic. The influence of changing climate over the sequential development of lithostratigraphic units also provided an additional stratigraphic tool. The unit D overlies lithostratigraphic units A through C with a distinct unconformity. However, in the Pranhita-Godavari and Johilla valley basins some workers recognized sequences of two C and D lithostratigraphic units. Our study instead, revealed the presence of only one each of lithostratigraphic units C and D in all the Gondwana basins. Improper definition of the Kamthi formation applying over reliance on mega plant-based biostratigraphy, and its dual stratigraphic setting created many problems. To resolve these, a Field Seminar was organized covering the Kamptee, the Satpura, the Pranhita-Godavari valley and the Johilla valley basins (latter being a part of Sohagpur coal basin). Study of critically chosen and representative sections in all these basins established unified Gondwana lithostratigraphy in the peninsular India.

6 illus, 4 tables, 63 ref

015139   Das S;Mistri B (NO, Burdwan Univ, West Bengal-713 104) : Tectono-Morphic analysis of upper Darkeswer basin, Purulia district, West Bengal. Trans Inst Indian Geogr 2015, 37(2), 281-90.

Tectonic deformations revise the relief of a terrain; topography gives the first and requisite indication of the distribution and arrangement of morphological structures. Tectonic activity plays an important part in developing drainage pattern and controlling river behavior. Fluvial geomorphology is essentially linked to tectonics. Rivers are sensitive to changes in tectonic deformation, adjusting over different periods of time depending on the physical properties of the underlying rocks, climatic effects and tectonic activities. Thus, the drainage system of a region records the evolution of tectonic deformation. The Darkeswer River, monsoon-fed river system, draining the western undulating plateau fringe of West Bengal in its upper domain which displays tectonically stable region has responded to slow tectonic movement in the basin. The region comprises an integral crustal segment of the Eastern Indian Shield (Chotonagpur Gneissic Complex) where hard, foliated, friable ancient hard rock of Precambrian age characterized by intense surface fracturing, fault, cracks, and lineaments exposed on the surface. The existence of flat wide valley with no such major variation of channel gradients, represents a comparatively balance situation where the Quaternary alluvium deposited. In some parts of this ancient landscape, however, the role of tectonic is indicated by the presence of incised valley and tilting of the basin. The region does not face any recent tectonic activity but imprints of tectonic controls are there. In this paper, we have attempted to understand the tectonic sensitivity with a look at the response of both types of tilting namely, longitudinal tilting and lateral tilting on the river system. We use DEM-based terrain analysis; geomorphic indices of active tectonics (GAT) such as HI, AF, Vf, SL index, Re and lineament study, to show that the rivers of the upland part of south-western Bengal have responded to slow and subtle tectonic movements. The results are consistent with field observations on landforms and geology.

2 illus, 2 tables, 26 ref

015138   Chaudhuri S N (NO, , Geological Survey of India, NEnR, Block DK 6, Sector II, Salt Lake, Kolkata-700 091, Email: sahnkar_swagata@yahoo.co.in) : Petrographic approach on suitability of a few coal seams for liquefaction in Talcher coalfield, Odisha, India. Indian J Geosci 2015, 69(2), 103-16.

Petroleum precursors are found in Indian coal although; in far lower concentrations than in oil source rocks. Similarly, as they are converted and incorporated into kerogen in the source rock, in coals they are apparently found mainly as hydrogen-rich, aliphatic edge groups on humic substances. To a lesser extent, the precursors are present as macerals of liptinite group, mainly alginite, resinite, bituminite, cutinite and liptodetrinite. It is observed that bituminization takes place with rising rank in the brown coal to sub-bituminous coal range. This is because petroleum-type hydrocarbons are formed at this stage from components of waxy leaf cuticles, pollen and spore coatings by chemical reactions. In context to the above it is interesting to observe that coal seams of Talcher Coalfield, so far studied, fulfil the requirement for potentiality of oil generation. In course of detailed petrographic studies of coal samples from different coalfields it has been characteristically observed that coals of Talcher Coalfield have higher contents of liptinite macerals (sporinite, sporangium, cutinite, resinite, alginite suberinite and liptodetrinite). These macerals have been recorded from most of the blocks so far explored by Geological Survey of India (GSI). Coal seams intersected in one of the boreholes in Jamujhari Block of Talcher Coalfield have higher content of liptinite maceral constituent (up to 53.6%). In other blocks of the same coalfield namely Jalatap Block, Sarapal-Nuapara Block and Kosala (E) Block, most of the coal seams are rich in liptinite content in variable concentrations from 5% to 32%. The liptinite group comprises macerals like, sporinite (both mico and mega), sporangium, cutinite and resinite. These macerals consist of sporine, cutin, suberine, resin, wax, fat and oil of vegetable origin. Rank-wise coal seams of Talcher Coalfield can be categorized under sub-bituminous to high volatile bituminous 'B' type. The values of vitrinite reflectance (Ro %) vary from 0.30% to 0.61%. Coal liquefaction is the procedure adopted in Indian scenario in the recent past to produce synthetic fuel as a substitute for crude oil. Coal quality required for liquefaction should be of low rank and high in hydrogen content. The desired high H/C ratio is intimately linked to rank and petrographic composition which requires the presence of a high proportion of reactive components, such as vitrinite and liptinite in the coal. The above study brings out suitability of coal seams of Talcher Coalfield for liquefaction due to their low rank and high reactive contents.It is worth mentioning that very recently South African company - Sasol and Tata Group were awarded the coal-to-oil project in Talcher Coalfield, Odisha. Sasol plans to produce 80,000 barrels a day of motor fuel by 2018 from a coal block in Odisha.

6 illus, 2 tables, 16 ref

015137   Chaturvedi R;Mishra S D (Geography Dep, Indira Gandhi National Tibal Univ, Amarkantak, Madhya Pradesh) : Geomorphic features and flood susceptibility zones: a study for Allahabad district, Uttar Pradesh, India, using remote sensing and GIS technique. Trans Inst Indian Geogr 2015, 37(2), 259-68.

Paper using satellite imagery and GIS attempts to associate geomorphology in defining flood susceptibility zones in Allahabad district, Uttar Pradesh, India. Varied landforms found in the district are the result of the processes of erosion and deposition that were operated in the past and are still continuing. Flood plain and associated features in the northern part of the district got formed during the Quaternary period whereas numerous landform features in the southern part were defined by the development of Vindhyan plateau during Pre-Cambrian to Recent periods.

1 illus, 1 table, 11 ref

015136   Blaiarsingh S K;Parida C;Lotliker A A; Srichandan S;Sahu K C;Kumar T S (NO, Indian National Centre for Ocean Information Services, Hyderabad-500 090) : Biological implications of cyclone Hudhud in the coastal waters of northwestern Bay of Bengal. Curr Sci 2015, 109(7), 1243-5.

4 illus, 12 ref

015135   Bhattacharyya T;Chandran P;Ray S K;Pal D K; Mandal C;Mandal D K (NO, National Bureau of Soil Survey and Land Use Planning, Nagpur-440 033) : Distribution of zeolitic soils in India. Curr Sci 2015, 109(7), 1305-13.

Calcium-rich zeolites control naturally occurring chemical degradation in the black soils (Vertisols and their intergrades). With the help of modern tools such as remote sensing, geographic information system, soil database, geological information, topography and other related datasets, an attempt was made to update the distribution of zeolitic soils in India. To ascertain the presence of Ca-rich zeolites in soils, mineralogical information was generated using X-ray diffraction techniques for the selected soils from the Indo-Gangetic Plains and the black soil region (BSR). The zeolitic soils are mostly confined in the pediments (sloping regions of the upland) of the Deccan plateau in BSR, although a few are also found along the valley floor. The IGP, on the other hand, hosts the zeolitic black soils along the drainage channels in the valley floor where the basaltic alluvium deposited the smectite and clay-rich sediments. The study indicates Ca-rich zeolitic soils in India to occupy an area of <126>2.8 m ha, of which BSR and IGP constitute <126>92% and <126>8% respectively. The zeolites are mostly concentrated in the drier tracts of the country and help in maintaining soil health against natural soil degradation. While the occurrence of Ca-rich black soils in BSR was known, those in the IGP are new findings. With the help of the available information, we have generated state-of-art information approximation map on the distribution of Ca-rich zeolites in Indian soils.

8 illus, 3 tables, 62 ref

015134   Bhattacharya A;Rudra R R;Gupta S;Chakraborty K;Bhattacharya A (Gemmology Laboratory, Geological Survey of India, NECGR, 15 A & B Kyd Street Kolkata-700 016, Email: baparajitagsi@gmail.com ) : Raman spectroscopy as a tool for differentiating natural gem variety corumdum from its syntheitic counterpart. Indian J Geosci 2015, 69(2), 169-73.

4 illus, 14 ref

014123   Sharma D K;Singh A (NO, ICAR-Central Soil Salinity Research Institute, Karnal, Haryana) : Salinity research in India- achievements, challenges and future prospects. Wat Energy int 2015, 58(6), 35-45.

Salinity is one of the major constraints in sustainable food production in many parts of the world. In a changing global scenario characterized by extreme climate variability, land and water degradation, biodiversity loss and trade regulations, the food and nutritional security of a burgeoning population is a cause for concern to the researchers and policy makers. As day-to-day increasing competition for productive lands and fresh water resources coupled with pervasive land use are pushing agriculture to the marginal environments, ensuring sustainable agricultural productivity and remunerative returns to the growers remain the major challenges. Since its establishment, ICAR-Central Soil Salinity Research Institute, Karnal has made significant contributions in harnessing the productivity of salt-affected soils and waters. In spite of credible achievements in the reclamation and management of saline and sodic soils for crop production, different soil, climatic, anthropogenic and policy constraints continue to hinder the productive utilization of vast saline tracts lying in arid, semi-arid and coastal regions of the country. After reviewing the current global trends, we proceed to scrutinize our strengths and weaknesses in salinity management in agriculture with a view to present a plausible future course of action while taking into account the present and emerging challenges.

90 ref

014122   Mondal M;Satpati L N (NO, Bhowanipur S.J. Institution, Hyderabad North 24 Parganas, West Bengal) : Long profile analysis of ichamati river with the help of best-fit curve, India. Indian J Geomorph 2015, 20(2), 109-24.

4 illus, 1 table, 59 ref

014121   Mondal B (Geography Dep, Sagar Mahavidyalaya, Harinbari, Sagar, 24 Praganas-740 373, Email: bikashmondal183@gmail.com) : Rehabilitation; A practical issue in the sundar bandeltaic area with special references to goramara island, South 24 parganas, West Bengal, India. Indian J Geomorph 2015, 20(2), 151-7.

Sundarban deltaic area is built up with the bunch of islands which is situated in the active deltaic region at the confluence of Ganga-Brahmaputra river. As a result, these islands are surrounded by brackish water bodies. Therefore erosional and depositional processes are going on at a same time. But some islands are eroding excessively. For this reason these islands have turned into endangered islands and the fact is that population of this islands becomes endangered in respect of their own settlements. For example Ghoramara and its surrounding islands are slowly abolishing or abolished by the erosional processes by the tidal surge and oceanic hazards. It is found that the islands of Lohachara, Suparibhanga, and Agunmari are at urge of abolishment and people of this area have needed rehabilitation from their own place to others and it will also suitable for Ghoramara island. At present Ghoramara island is maintaining its existence somehow or other. This Present paper deals with the problem of rehabilitation of people and proposes to some in situ and ex situ rehabilitation measures for long term or short basis.

1 illus, 10 ref

014120   Manjare B S;Khan S;Jawadand S;Padhye M;Raut T (Geology Dep, RTM Nagpur Univ, Nagpur, Maharashtra, Email: yogesh_manjare1@rediffmail.com) : Morphometric analysis of sun-watershed in some part of wardha river basin, Maharashtra India using geospatial techniques. Indian J Geomorph 2015, 20(2), 125-36.

Attempt has been made to study drainage morphometry and its influence on hydrology of Wardha River sub watershed, Maharashtra, India. For detailed study we used Advanced Spaceborne. Remote sensing and Geographical information system (GIS) ware used in evaluation of linear, areal and relief aspects of morphometric parameters. The study reveals that the elongated shape of the basin is mainly due to lithological and topographical control. The lower order streams are mostly dominating the basin. The development of stream segments in the basin area is more or less affected by rainfall. The mean bifurcation (Rb) indicates that the drainage pattern is not much influenced by geological structures. Relief ratio indicates that the discharge capability of these watersheds is very high and the groundwater potential is meager. These studies are very useful for planning rainwater harvesting and watershed management.

2 illus, 4 tables, 14 ref