bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Note on the Auriferous Banded Iron-Formation of Kolar Schist Belt
Authors: Natarajan W. K. , Mukherjee M. M. 
Published: November 2024

Abstract
Banded Iron-Formation (BIF) comprising quartz, pyrrhotite/grunerite-actinolite and quartz, magnetitejgrunerite-actinolite occurs widely in Kolar schist belt as narrow (0.5 rom to few tens of metres wide) interbeds within the metamorphosed basic volcanic and acid volcanogenic rocks (' Champion gneiss '). All gradations between these two end members render the BIF bands heterogeneous in composition. The sulphidic BIF horizons occurring near the western margin of the schist belt in association with pillowed metabasaJts are persistent along strike for several kiJometres and are auriferous at places. The BIF horizons occurring towards the eastern margin of the schist belt are narrower) impersistent in strike and are not known to contain gold mineralization.
Two types of mineralization have been recognised in BIF. In sulphide facies BIF, native gold occurs in arsenopyrite which along with pyrrhotite and amphiboles form massive layers alternating with quartz. Here the auriferous sulphide layers are primary, subsequently modified by metamorphism and deformation. In the second type, gold mineralization is confined to syntectonic quartz veins in the sulphidic BIF. A volcanogenic model for the precipitation of auriferous BIF is favoured.
The Cycling Redox State of Iron in the Genesis of Banded Iron-Formations and their Associated Enrichment Iron Ores
Authors: Morris R. C. 
Published: November 2024

Abstract
A simplified eclectic model for the genesis of Banded Iron-Formation (BIF) and associated iron ores in the Hamersley Group of Western Australia can be applied with suitable modifications to comparable situations elsewhere.
BIF was deposited from upwelling ocean currents as a chemical sediment in a platformal environment. Ferrous iron and silica were supplied to seawater by direct input from rivers and sediment-seawater reactions, forming a general background level which was periodically supplemented by exhalative components from major submarine'hot spot' activity. Iron was precipitated largely by photo-oxidation of ferrous iron as it reached the surface rather than by a more commonly advocated biochemical process. During early diagenesis ferrous minerals, such as magnetite, were formed.
Following consolidation, folding and exposure, supergene enrichment occurred in suitable hydrodynamic systems enabling deep ores to form in the BIF while the surface eroded. The enrichment in these small artesian systems was controlled by large electrochemical cells driven by oxygen reactions in the outcrop. This allowed ferrous to ferric reactions to occur at depths well beyond the reach of atmospheric oxygen. Burial and subsequent metamorphism of such goethite-rich deposits, particularly those formed during the Precambrian, resulted in the development of hematite-rich ores. Some of these have been thermally metamorphosed by igneous intrusions to give magnetite-rich deposits. Later re-exposure has further modified the ores by leaching, oxidation, dehydration and surface lateritisation.
Ores formed during later periods are generally unmetamorphosed and retain their goethite-rich character. These have been modified by continuing exposure and are commonly strongly leached.
Loess Deposits of Kashmir, Northwest Himalaya, India
Authors: Pant R. K. , Dilli K. 
Published: November 2024

Abstract
The spatial and temporal variation of Kashmir loess deposits has been explained as the function of palaeotopographical configuration consequent to the Pir Panjal Range uplift datable at 0.4 m.y. At least three palaeosurfaces were available for loess deposition at different time intervals. Three types of loess-palaeosol profiles developed on these palaeosurfaces which show altitudinal differences. Stratigraphical correlation between different profiles was possible with the help of marker beds and soil typological parameters. Seven lithounits constitute the total loess-palaeosol succession in the basin. Soil types were recognised using sedimentological, mineralogical and microfabric parameters in addition to field criteria.
Charnockite 'in the Breaking': Evidences from the Trivandrum Region, South Kerala
Authors: Santosh M. , Yoshida Marasu 
Published: November 2024

Abstract
Field and microstructural evidences indicating retrogressive-transformation of banded charnockite to leptynite (garnet gneiss) through a transition zone of khondalite (garnet biotite gneiss) is reported from two localities in south Kerala. In the same localities, formation of acid charnockite patches are also noted. Structural analyses show that the breaking event post-dates the formation and isoclinal folding of banded charnockite, but clearly pre-dates the making of patchy charnockite.
Crenulation Cleavage in Slate of the Chamba Syncline: Associated Microstructures and Origin
Authors: Singh Keser , Thakur V. C. 
Published: November 2024

Abstract
The microstructures associated with the crenulation cleavage in the slates of the Chamba Syncline, Western Himalaya, indicate that metamorphic differentiation following differential plastic flattening and fracturing is largely responsible for its origin. The stress gradient leads to migration of soluble minerals like quartz and calcite from limbs to hinge regions of microfolds as a result of pressure solution leaving behind micarich bands (insoluble) defining the crenulation cleavage.
Scanning Electron Microscopy Study of the Quartz Overgrowths Within Neogene Sandstones of Bengal Basin, Bangladesh
Authors: Imam Md. Badrul 
Published: November 2024

Abstract
Scanning electron microscopy study reveals successive stages of quartz overgrowth development during post depositional burial diagenesis in the Neogene sandstones of the Bengal Basin. The quartz overgrowths are most abundant and form major cement in Bhuban sandstones, are less common in Bokabil sandstones, While they are rare in Tipam sandstones. The growth of authigenic quartz proceeds from initial incipient and isolated quartz crystals to advance-terminated and euhedral quartz overgrowth completely engulfing the host detrital grain - the latter being formed by mergence of the incipient quartz units into a single unit. Mutual interlocking of adjacent quartz overgrowths of advance stage frequently produce sutured type contact that may be mistaken as pressure solution under optical petrographic studies. Development of quartz overgrowths is inhibited or retarded by the presence of thick authigenic chlorite rims around detrital grains. Two most important sources of quartz overgrowths are the pressure solution and the smectite to illite diagenesis in illite/smectite mixed layer clay mineral in the interbedded shales.
Garnet + 2 Sillimanite = 3 mg-Spinel + 5 Quartz Equilibrium-A Potential Geobarometer
Authors: Bhattacharya A. , Mazumdar A. C. 
Published: November 2024

Abstract
A geobarometer based on the equilibrium Mg3Al2Si3O12 + 2Al2SiO5 (sillimanite) = 3MgAl2O4+5SiO2 has been proposed. The geobarometric expression can be stated as P(bar)=9.68 T - 7106 + 10.307 T In (agarnetMg3Al2Si3O12)1/3/(aspinelMgAl2O4). Application of the proposed geobarometric formulation to some metapelites indicates that it registers reasonable pressure values which are in good agreement with the recommended pressure values for different terranes.
Petroleum Hydrogeology: A Potential Application of Groundwater Science
Authors: Toth J. 
Published: November 2024

Abstract
Hydrogeological principles and techniques may be useful in petroleum exploration and basin analysis because of two kinds of genetic relations between accumulations of petroleum and regional groundwater flow. First, groundwater flow may create deposits by transporting hydrocarbon particles toward and into sites where conditions for accumulation and entrapment are fluid-dynamically favourable. Second, groundwater flow may reveal deposits by indirect or direct signatures transmitted from potential sites of or actual accumulations, respectively, to locations where they can be detected. Knowledge of groundwater flow pattern thus allows identification of dynamically favourable regions for deposit formation as well as projections to be made in the directions of both developing and eroding deposits. Groundwater flow may be studied by mathematical and field-oriented techniques, and by using its own physical, chemical and thermal manifestations. The four basic types of petroleum exploration problems to which hydrogeology might be applied are: 1. Areal reconnaissance ; 2. Estimates of migrated hydrocarbon volumes; 3. Location of hydrodynamic traps and extension of known deposits ; and 4. Surface exploration. Even though it is not possible to precisely estimate the economics of a groundwater based approach in petroleum exploration, a cost-saving of up to 50% in regional surveys on continental areas may be expected and there is a strong case for a field-test of the concepts.
Groundwater Recharge Estimates by Radio-Isotope Method-A Critical Analysis
Authors: Krishna Rao G. 
Published: November 2024

Abstract
Isotopes have a wide application in groundwater problems like recharge estimates. Though the results of this method are nearly convincing, the concept behind the method is not. The radio-active tracer movement in the unsaturated zone represents only soil moisture transport which is not available for exploitation as groundwater. The exploitable groundwater corresponds to the 'gravitational water' component of the infiltrating waters.
Drastic: A Standardized System to Evaluate Groundwater Pollution Potential using Hydrogeologic Setting
Authors: Aller Linda , Lehr Jay H. , Petty Rebecca , Bennett Truman 
Published: November 2024

Abstract
DRASTIC is a methodology which allows the pollution potential of any area to be systematically evaluated. The system optimizes the use of existing data and has two major portions: the designation of mappable units, termed hydrogeologic settings, and the superposition of a relative ranking system called DRASTIC. Hydrogeologic settings incorporate the major hydrogeologic factors which are used to infer the potential for to enter groundwater. These factors form the acronym DRASTIC and include depth to water, net recharge, aquifer media, soil media, topography, impact of the vadose zone and hydraulic conductivity of the aquifer. The relative ranking scheme uses a combination of weights and ratings to produce a numerical value, called the DRASTIC Index which helps prioritize areas with respect to pollution potential.
Optimization of Unconfined Groundwater Systems: A Differential Dynamic Programming Algorithm
Authors: Willis Robert , Jones LeDon C. 
Published: November 2024

Abstract
Groundwater optimization models are predicated on the hydraulic or water quality response equations of the aquifer system. These equations relate the state variables of the groundwater system, the head or mass concentrations, and the decision variables that control the magnitude, location, and timing of pumping, artificial recharge, or waste injection. These management models are large-scale, non-convex programing problems. The objective of this paper is to present a differential dynamic programming (DDP) algorithm for solution of groundwater optimization problems. The effects of state and control variable constraints are discussed. The Jacobian matrices of the algorithm are evaluated analytically using a fully implicit, finite difference model of the aquifer system. DDP is used to identify optimal groundwater pumping schedules for a two-dimensional, unconfined aquifer system. The CPU time and central memory requirements of the algorithm are also presented.
Environmental Geochemistry of Indian River Basins-A Review
Authors: Subramanian V. 
Published: November 2024

Abstract
Based on extensive observations, the sediment and the chemical load- both quantity and quality - have been computed for the Indian sub continent. Indian rivers carry total dissolved solids of 159 ppm, which is about 25% more than the world average river water. Indian rivers are also relatively enriched in Na and Cl. They also carry a sediment load of about 1.4 billion tonnes/yr representing 10% of the global sediment flux. The northern rivers carry dominantly illite-kaolinite-chlorite in suspension while the southern rivers carry high exchange capacity clays. The sediment chemistry is comparable to world surface rocks, with corrections for the mobile elements. Heavy metals occur predominantly in the chemically extractable sinks within the river sediments. Limited studies on base metal mining areas in Khetri and Zawar indicated contamination of soil, plants and water in that area.
The Distribution of Intensity Associated with the 1905 Kangra Earthquake and Bounds on the Extent of the Rupture Zone
Authors: Molnar Peter 
Published: November 2024

Abstract
In his report of the damage caused by the 1905 Kangra earthquake, Middlemiss (1910) reported two zones of relatively high intensity: a major one with a maximum near Kangra and Dharamsala and extending southeast to Mandi, and a minor one centered around Dehra Dun. A re-examination of the information that he gave suggests that the intervening zone of low intensity was not well-defined and that the intensity near Dehra Dun was not markedly higher than that at towns in the plains of northern India. Thus, these observations allow three different possibilities for the extent of the rupture zone. The rupture may have extended southeast 280 km, from west of Dharamsala to southeast of Dehra Dun. In this case the rupture probably occurred on segments of two thrust faults connected by a strike-slip fault in the hanging wall (or by a buried lateral ramp) north of Simla. Possibly there were two separate ruptures: one extending from near Dharamsala southeast to Mandi and the other, poorly defined, near Dehra Dun. Finally the distribution of destruction allows for the possibilities that only the area 100km in extent, from west of Dharamsala to Mandi, ruptured and that the 1905 earthquake did not relieve much strain in the region near Dehra Dun. Accordingly, it probably is safe to assume that Dharamsala will not lie in the epicentral area of the next great earthquake in the Himalaya, but it probably would be unwise to assume that that area will not include Dehra Dun.
Economic Potentiality of New Gold Mineralisation in South Kolar Schist Belt
Authors: Mukherjee M. M. , Natarajan W. K. , Shashidharan K. , George Stephen 
Published: November 2024

Abstract
Auriferous zones are confined to ductile shear zones in the mafic unit (metabasalt/metagabbro) as well as in the felsic unit ('Champion gneiss'). The occurrence of significant gold mineralisation in the' Champion gneiss' comprising quartzo-feldspathic schist is being reported for the first time.
Low grade (about 4 grammes per tonne) gold reserve of the order of 4.7 million tonnes under all categories (probable+possible) in the new prospect has been established.
Correlation of Cave Levels and Planation Surfaces in the Pachmarhi Area, Madhya Pradesh: A Case for Base-Level Control
Authors: Venkatakrishnan Ramesh 
Published: November 2024

Abstract
Strong spatial juxtaposition of stream entrenchment and cave levels with planation surfaces in the Pachmarhi area reveals their mutual synchroneity during recurrent periods of epeirogenic uplift and stillstand that characterized the post-Deccan Trap (middle to late Cenozoic) erosion cycle.
Best correlation of cave levels with planation surfaces is observed in the downstream reaches of the drainage basins far removed from the drainage divides. Cave levels closely mimic the epeirogenically warped Upland planation surfaces indicating their base level control. Cave systems in the headwater regions are less well developed and appear to be controlled more by local tributaries. Both these observations indicate that trunk streams approach equilibrium sooner than their headwater reaches and hence cave levels cluster around the planation level in the downstream reaches where planation surfaces are also better developed. Periods of stillstand are therefore marked by intense cave development and periods of downcutting by stream entrenchment and drainage superposition.
Cave development and landform evolution in the Pachmarhi Area appear to be a non-cyclic but continuous process of recurrent epeirogeny and stillstand during the later part of the Cenozoic Era.
Offshore Extension of the Structural Element at Udipi, Confirmation from Marine Magnetics
Authors: Subrahmanyam V. 
Published: November 2024

Abstract
The isomagnetic anomaly map (1: 3,00,000) reflects conspicuous E-W, NW-SE, WNW-ESE, NE-SW and N-S trends which are similar to that of the onshore Dharwar trend. The map also shows short wavelength, high amplitude anomalies off Coondapoor, broad wavelength anomalies off Mangalore and relatively smooth zone further south to Kasaragod. A prominent WNW-ESE structural element (fault) south off Coondapoor is observed in the three eastern profiles (A-A', B-B' and C-C') which was not reflected in the western profiles (D-D', E-E' and F-F') and this can be extrapolated towards the adjacent coast to join an onshore structural element trending in the same direction. This structural element perhaps represents the offshore extension of the fault at Udipi. The broad wavelength anomalies off Mangalore and Malpe may be generated from sources composed at a depth of around 4 km. The observed magnetic smooth zone south off Mangalore is interpreted in terms of insignificant magnetization contrast in the crystalline basement.
Univariate and Multivariate Stochastic Modelling and Forecasting of Silica Content in Iron Ores of Northern Goa
Authors: Raikar P. S. 
Published: November 2024

Abstract
The distribution of silica (SiO2) content in the iron ores of Northern Goa (Bicholim Mine) was found to be a stationary process by itself and no differencing was heeded for stochastic modelling. The univariate method established an AR (1) process for lateral series (65 samples taken at 3 m interval along strike of the ore body); as well as for vertical series (35 samples taken at 1 m. interval perpendicular to bedding plane) with maximum likelihood estimators of f1 =0.544 and 0.803 for lateral and vertical series respectively.
The univariate forecasts have been upgraded by multivariate analysis techniques after prewhitening the input series. Step-wise multiple regression has resulted in a reduction of error variance (R2) by 27.33% along lateral series with statistical significant inputs of TiO2 and MnO; whereas for vertical section, it yielded simple regression retaining significant input of FeO2O3 and reduced the final error variance by 26.71 %. Some practical aspects of grade forecasting and utility of the models so generated are discussed.
Seasonal Beach Changes Along Quilon District Coast, Kerala
Authors: Prakash T. N. , Aby Verghese P. 
Published: November 2024

Abstract
Based on the beach profile studies along the Quilon coast during the year 1980-81, accretional and erosional areas were demarcated in the southern and northern sector of the Neendakara outlet. A net gain of 0.194 m3 of sand in the southern sector and loss of 0.374 mimon m3 in northern sector was noticed. There is marked variation in mean grain size, sorting and foreshore slope in these two sectors. Reversal of longshore current from north to south, increase of breaker height and human activity have been found to be responsible for overall beach changes along the coast.
On the Evolution of the Lagoon Barrier System Between N. Lats. 12°5' and 12°15', Cannanore District, Kerala
Authors: Thrivikramaji K. P. 
Published: November 2024

Abstract
The Ettikulam lagoon and the lagoonal islets lying in the coastal plain of Cannan are District, Kerala form typical lagoon-barrier complex. A series of islets dot its full length, and some of the northern islets show a boomerang shape in plan. Other important components are the modern Ettikulam barrier, the Laccadive sea to the west and the coastal plain to the east. The islets occurring in the lagoon are interpreted as remnants of a barrier-dune complex, which was dismembered into fragments (sandy shoals) by storms in the Laccadive sea at a time when the sea-level was also on the rise (in the late Pleistocene). The storms also hastened the reduction of relief of the fragments or protoislets. The destructive phase of the islets terminated with the emergence of the modern Ettikulam barrier, giving the present configuration to the shoreline.
The onset of the new flow pattern, controlled by the two inlets, one off the mouth of Karingote river in the north and the other near Ramanthali in the south, led to further modification of the plan view of the islets giving a boomerang shape.
Evidences are also cited for the migration of the northern inlet and for the closure of the inlet near Ramanthali in the south, mainly due to littoral drift, sometime between 1914 and 1965.
Origin of Calcrete in Red Sediment from Visakhapatnam Coast, Andhra Pradesh
Authors: Sankara Pitchaiah P. 
Published: November 2024

Abstract
Red sediment with calcrete is a characteristic deposit in the coastal tracts of Visakhapatnam region on the northeastern part of Andhra Pradesh. Three structural types of calcrete. rhizoconcretionary, mottled and massive, are recognized from Ramakrishna Mission, Rishikonda and Bhimilipatnam areas. Rhizoconcretionary calcrete is recorded from three profiles, but the mottled and massive are typically absent in Bhimilipatnam.
The origin of the various types of calcrete in the Visakhapatnam area is intimately linked to evapotranspiration of groundwater. The rootlet origin of the calcrete structures is beyond doubt, as the actual woody tissue of the root is occasionally found as a core to the rhizoconcretions.
The massive calcrete is precipitated much above the present day water table which, in general developed in the capillary-rise zone, indicating the rise in palaeo-water table. The well-developed calcrete profiles of Ramakrishna Mission and Rishikonda suggest the possible existence of a grove of old trees in the past. On the other hand, poorly developed calcrete profile of Bhimilipatnam indicates the palaeo-heath/scrub vegetation.
Dinosaur Teeth from Lameta Group (Upper Cretaceous) of Kheda District, Gujarat
Authors: Mathur U. B. , Srivastava S. 
Published: November 2024

Abstract
Theropod and sauropod dinosaur teeth are being described for the first time from Lameta Group (Upper Cretaceous) of Kheda District, Gujarat. Carnosaurian teeth show megalosaurid characters and are placed in Majungasaurus (Megalosaurus)crenatissimus and (?) Megalosaurus. Five morphological types of (?) Megalosaurus teeth have been distinguished which vary from laterally compressed flattened cones to recurved ones having serrations on anterior/posterior margins and directed either at right angles or obliquely to the margins. The sauropod dinosaur teeth are tentatively placed in Titanosaurus and described as a new species viz., (?) Titanosaurus rahioliensis.