bluuebunny/crossref_metadata_2025_split huggingface dataset:
Petrology of Jutogh Metapelites near Chaur, Himachal Himalaya, India
Authors: Das Brijraj K. , Rastogi R. 
Published: November 2024

Abstract
The Jutogh metasediments in Chaur area have undergone three phases of deformation D1, D2 and D3 respectively, associated with two metamorphic episodes M1 and M2. The M1 episode was synkinematic in relation to the F1 folding phase (D1) and continued postkinematically to F1. reaching its climax during a static phase between D1 and D2. Most of the porphyroblastic minerals such as staurolite, kyanite, sillimanite and even garnet crystallized during this period. The M2 metamorphism superposed M1 during D2 deformation and was of retrograde nature. The isograds have been delineated by specific mineral reactions and the zones are characterised by critical mineral assemblages.
Metamorphic conditions suggest pressure of about 6.0 (±0.5) kb, and temperatures of 540°C (±10°C), 560°C (±10°C), 640°C (±10°C) and 650°C (±10°C) in zones (B) garnet-chlorite, (C) staurolite-biotite, (D) kyanite-biotite and (E) sillimanitegarnet-biotite, respectively.
Petrogenesis of Basalts: Examination of REE Data Using Pattern Recognition Approach Through Principal Component Analysis
Authors: Arunachalam J. , Murali A. V. , Sankar Das M. 
Published: November 2024

Abstract
A pattern recognition (PR) approach based on the principal component analysis (PCA) is adopted for the petrogenesis of basalts using the relative behaviour among the REE, on the data-sets of tholeiites (MOR, ocean island and continental) and alkalic basalts (melilites, nephelinites and alkali olivine basalts). It is observed that the overall variability in the REE data requires two or three principal components; with the first component accounting for 80% of the variability. The coefficient patterns of these components reveal distinct features. The dominant (first) component of tholeiites, exhibits a poor covariance of La and Ce with MREE. Coefficient patterns of the dominant component of tholeiites show breaks at Sm and at Dy/Tb similar to those observed in high pressure partition coefficients for cpx. The coefficient patterns in this major component appear to describe the REE behaviour during partial melting and high pressure fractionation of opx or cpx and eclogite.
In contrast with the tholeiites, the dominant component in alkalic basalts, shows excellent covariance among the LREE and MREE. Among the alkalic basalts, the alkali olivine basalts, show a different HREE behaviour. Comparison of the coefficient patterns of the dominant component of tholeiites and alkalic basalts suggests distinct differences in their source/mechanism of formation.
Theoretical computations involving partial melting and fractional crystallisation of only the major mineral (ol, opx, cpx, garnet/spinel) prove to be inadequate to simulate the observed coefficient patterns. The inclusion of 87Sr/86Sr isotopic ratios along with REE in the PCA, generates 'features' suggestive of additional sources (interstitial liquid, accessory minerals in the mantle and/or granitic crustal contamination) as contributing factors.
The PR approach described in this work allows one to extract more information from the REE data-set than what is possible by simple chondritic normalisation.
Structures and Textures of Vanadium-Bearing Titaniferous Magnetite Ores and their Interpretation
Authors: Chakraborty K. L. , Roy Jishu , Majumder Tapan 
Published: November 2024

Abstract
Various types of exsolution and replacement structures and textures uf the vanadium-bearing titano-magnetite ores have been described from the titano-magnetite deposits occurring in the gabbro-anorthosite complexes of Orissa, India. Attempt has been made to correlate different textures to various oxidation stages. The ores were formed within the temperature range of 600°-800°C and average fO2 = 18.4.
Geology of Greywackes West of Ranibennur, Dharwad District, Karnataka State
Authors: Chavadi V. C. , Hegde V. S. 
Published: November 2024

Abstract
The greywackes of Ranibennur are granodioritic in composition, and have been deposited in eugeosynclinal basin under reducing conditions. Matrix of the greywackes indicates operation of more than one process for its origin.
Silica Bead Industry in Cambay, Gujarat State, India
Authors: Karanth R. V. 
Published: November 2024

Abstract
Silica bead manufacturing industry in Cambay has a tradition of more than two thousand years. Even today it forms an important cottage industry in Gujarat. With the indigenously developed age-old methods of bead making, this industry here is successfully competing with other bead industry centres in the world. Only recently mechanised grinding and tumbling processes have been adopted. However, the concept of tumbling is not entirely alien to this cottage industry, because some forms of manunl tumbling were in practice in earlier years.
Foraminifera from Shore Sands of Bhatkal and Devgad Islands, West Coast of India
Authors: Shareef Nayaz Ahmed , Venkatachalapathy V. 
Published: November 2024

Abstract
Investigation of foraminiferal microfauna of the shore sands of Bhatkal and Devgad islands (Karnataka) , west coast of India, has facilitated recognition of 40 species from Bhatkal and 41 species from Devgad islands. A check list and illustrations for the species identified are provided. Three species are recorded for the first time from Indian waters. Based on population characteristics and distributional pattern, depositional environment and Indo-Pacific affinities of the microfauna are elucidated.
Monitoring Landslides in Dihang and Subansiri River Basins, Arunachal Pradesh
Authors: Prakash P. , Parthasaradhi E. V. R. 
Published: November 2024

Abstract
A study of aerial photographs taken before and immediately after the Great Assam Earthquake of 15th August 1950 revealed that the event had caused extensive landsliding in the northeastern India, including parts of catchments of Dihang and Subansiri rivers. Examination of the photographs of the same areas taken during 1959-60 and 1976-77 showed, that majority of the slopes that failed as a result of the earthquake, got stabilised to a large extent and some fresh landslides occurred during the period in a few areas.
Air-photo study shows that (i) the highly jointed nature of the Miri Quartzite has contributed to the maximum incidence of landslides in any particular lithological unit. (ii) The Main Boundary Fault and the system of faults parallel to it, in the Subansiri catchment have been reactivated during the Assam earthquake. (iii) In Dihang catchment, the MBF, and the Siang fracture have been reactivated.
In view of the possibility of fluid pressure exerted by impounding large quantities of water triggering off a major earthquake, it is suggested that construction of very large dams be avoided, even though the region has a very high hydel power potential.
Trace Fossils from Cambrian Tal Formation, Himachal Lesser Himalaya, India, and their Stratigraphic Significance
Authors: Mathur V. K. , Joshi Ashutosh , Kumar Gopendra 
Published: November 2024

Abstract
Two assemblages of ichnofossils are recorded from the Cambrian Tal Formation, Nigalidhar Syncline, Himachal Lesser Himalaya. The assemblage-I. occurring in the Arenaceous Member 300m below the horizon yielding redlichiid trilobite and brachiopod faunas of Tsanglangpuian Stage of Early Cambrian, contains forms like Rusophycus sp. aff. R. carinata Seilacher, monomorphichnus lineatus Crimes, Diplichnites spp.) Gordia sp., Astropolichon sp., ichnogenus A and ichnogenus B. The assemblage-II, in the Phulchatti Member ('Upper Tal'), includes Cruziana sp. and ichnogenus C cf. Buthotrephis. It occurs in sediments 70 m above the horizon containing trilobites and brachiopods. The former assemblage is of world-wide distribution in Lower Cambrian (upper Meishucunian to Lower Qiongzhusian), and thus, in the absence of microfauna, can be utilised in identifying Early Cambrian successions.
Morpho-Chemistry of Rutile in Dengura Manganese Ore Bodies of Koira Valley, Orissa
Authors: Mohapatra B. K. , Natarajan R. , Paul A. K. , Sahoo R. K. 
Published: November 2024

Abstract
Minute discrete grains of rutile present in manganese ores of Dengura, Koira valley, Sundergarh district, exhibit imperfect columnar and crystallographic forms and an outstanding illustration of twinning. EPMA and EDAX results indicate the presence of Fe, Mn, Cr, Al, Ba, K and Ta, Nb in minor proportion, in rutile crystals. Some of these clements are either present in limited solid solution or later got introduced into its structure during late epigenetic processes. These are detrital grains, pre-existing in the host shale and later affected by solution during epigene manganese are formation.
The Conglomerates of Holenarasipur Schist Belt and the Nature of Pre-Holenarasipur Crust of Peninsular India
Authors: Hussain S. M. , Naqvi S. M. 
Published: November 2024

Abstract
Two types of conglomerates occur in the Holenarasipur schist belt. The Tattekere conglomerate occurring in the older horizon (&gt;3.4 b.y.) ofthe belt is oligomictic and is tectogenic (autoclastic), devoid of pebbles of detrital sedimentary origin. The Gopalapura conglomerate occurring in the younger horizon (3.2 to 3.0 b.y.) of the belt is, on the other hand, polymictic and sedimentogenic. Occurrence of gneiss pebbles in this conglomerate indicates presence of gneissic terrain in the source area and strongly supports the view that considerable sialic crust had evolved before the younger greenschist sequences were deposited in this region. This extensive crust is formed by widespread emplacement of acidic plutons during the time gap between the older and younger sequences of Holenarasipur. It is proposed that older Holenarasipur schists and gneisses which intruded it supplied the debris to the younger belt.
Petrochemistry of Basics and Metabasics, Mandi-Pandoh Area, Himachal Pradesh, India
Authors: Gupta L. N. , Chaudhri Naveen , Prasad A. K. 
Published: November 2024

Abstract
Basic and metabasic rocks occur in the form of an oval-shaped, plug-like body. intrusive into the granitic gneisses and metasediments belonging to the Chail Formation. The core is made of fresh olivine gabbro metamorphosed to varying degrees at the margins. Chemical data suggest that the basic and metabasic rocks are co-magmatic and the parent magma was of alkali olivine basalt composition. The observed diversity in physical and textural parameters exhibited by different rocks are considered to be the expressions of varying rates of cooling and effects of autometamorphism. These are more pronounced at the margins than in the central parts of the body.
Water and Sediment Load in Streams Draining Mussoorie Phosphate Mining Areas
Authors: Singh B. K. , Subramanian V. 
Published: November 2024

Abstract
Water quality studies in the mining areas clearly point out to the contributions made by the mining activity to the chemical composition of Bandal flver in the Durmala and Maldeota region Levels of phosphates and fluofide in the water are enhanced even in canal waters in the Debra Dun region Drinking water in some taps in Doon valley also show higher levels of contammation for F and P The Bandal fiver carnes total dissolved solids of about 550 ppm which is much higher than the average Indian and world river waters Throughout the region all surface waters are supersaturated With respect to fluorapatite, hydroxyapatite and carbonate apatite. In reality, this equilibrium assembly is not reflected in the phosphate minerals present In tbe river sediments Phosphate minerals constitute nearly half the population of the alluvial sediments in the region with pockets of pyrite minerals up to 10% of the sediments by weight Trace elements like Cu, Cr and F show good Correlation with the P content in the sediment suggesting common sites within the sedlment grains.
Stratigraphy and Structure of Late Archaean, Dharwar Volcanic and Sedimentary Rocks and their Basement in a Part of the Shimoga Basin, East of Bhadravathi, Karnataka
Authors: Chadwick B. , Vasudev V. N. , Jayaram S. 
Published: November 2024

Abstract
The Dharwar Supergroup in the Shimoga basin east of Bhadravathi has been subdivided into seven formations on the basis of sedimentary structures and facies. The lowest is dominated by metabasites including metalavas and tuffs, metagabbros with seams of titaniferous magnetite, serpentinites and talc schists. A range of sedimentary rocks including phyllitic greywackes, quartzites, dolomitic limestones, conglomerates and local banded ferruginous cherts characterise the formations overlying the metabasites. These formations include local metabasites, and the youngest formation contains a thick suite of metarhyolites. The Dharwar lithostratigraphy is characterised by rapid lateral variations in thickness and facies which are the consequence of its original unstable alluvial and relatively shallow marine depositional environments. The instability is marked by slump structures in the phyllitic greywackes and by debris flows at many levels in the stratigraphy. The Dharwar rocks were deposited on a basement of homogeneous granodiorite s.l. and foliated multiphase quartzo-feldspathic orthogneisses. Erosion of elevated parts of the basement and the Dharwar cover provided detritus for alluvial fans, shallow marine quartzites and more distal phyllitic greywackes. Correlation of the lowest formations in tbe Bababudan basin immediately to the south shows that the Dharwar Supergroup becomes progressively younger from south to north in this part of Karnataka.
The structure is characterised by large upright synclines in the Dharwar cover with intervening domal areas of basement. Many of the cover-basement contacts are faults, but some are interpreted as rotated and steepened unconformities. Flushing of water and CO2 through much of the basement and cover took place during deformation. Buoyancy forces related to heating at deep crustal levels and concomitant compressional forces, generated perhaps in a transpressive oblique-slip regime, may account for the structure of the cover and its basement. Comparable tectonothermal instability, but with trans-tensile components, may have characterised the Dharwar volcanic and depositional phases.
A Comparative Study of Transmissivity Values Obtained by Slug-Test and Pump-Tests
Authors: Karanth K. R. , Prakash V. S. 
Published: November 2024

Abstract
The paper deals with the comparative study of the transmissivity values obtained by slug-tests and pump-tests on 58 wells drilled by DTH rigs in crystalline rocks comprising granites, gneisses, schists and basalts. The present study indicates that transmissivity values obtained by two methods vary mostly within a factor of three, except for pump-test T values of less than 10m2/day.
History of Successive Deformations in Relation to Metamorphism-Migmatitic Events in the Schirmacher Hills, Queen Maud Land, East Antarctica
Authors: Sengupta Sudipta 
Published: November 2024

Abstract
The basement complex in the Schirmacher Hills of East Antarctica records the impress of multiple episodes of metamorphism, migmatization and deformation. In the earliest event there was a regional metamorphism under granulite facies conditions and synkinematic migmatization leading to the development of charnockitic rocks. An amphibolite facies metamorphism was superimposed on them. This late event was closely associated with widespread granitization leading to the development of the majority of the quartzofeldspathic gneisses. In the earliest deformation, a migmatitic banding and a crude foliation formed in the charnockitic rocks. This was followed by a period of strong deformation during which two broadly coaxial sets of isoclinal folds (F2A and F2B) formed. The folding movement was also associated with widespread ductile shearing. The periods of amphibolite facies metamorphism, extensive granitization, F2 folding and the major phase of ductile shearing were overlapping. Localized pegmatite bodies were also emplaced during the later and much weaker folding movements of F3 and F4 and along some discordant ductile shear zones cutting across the axial surfaces of F2 folds.
Ecologic Distribution of Planktonic Foraminifera in the Bottom Sediments of the Northwestern Part of the Bay of Bengal
Authors: Pal Elonee 
Published: November 2024

Abstract
Ecologic distribution of the four abundant species of Planktonic foraminifera Globigerina bulloides, Globigerinoides rubra, Globigerinoides triloba and Neogloboquadrina dutertrei from the bottom sediments are described. The mode of analysis of distribution pattern followed can be used effectively for determining the paleoenvironment of ancient shelf area which bordered the mainland and whose physical environmental conditions were controlled by large river systems.
Analysis of the Gravity Field Over Parts of South Singhbhum, Sukinda Ultramafic Complex and Nature of Sukinda Thrust
Authors: Verma R. K. , Mukhopadhyay M. , Subba Rao P. B. V. , Satyanarayana Y. 
Published: November 2024

Abstract
A regional gravity survey has been carried out over the area lying between latitude 20°30' to 21°30'N, and longitude 85° to 86°15'E, forming a part of south Singhbhum geological province and northern part of the Eastern Ghats. The area is well-known for Sukinda ultramafic complex, Diateri and Malayagiri iron-ore deposits as well as Sukinda thrust.
Nearly 350 gravity stations were established along main roads, forest roads and cart tracks. Bouguer anomaly map of the area shows gravity highs over the Diated iron-ore group, the Malayagiri volcanics, the Sukinda ultramafic complex as well as over the Eastern Ghats province. Two-dimensional models. have been prepared to show the nature of the ultramafic complex, iron-ore group (lOG) of rocks and the Sukinda thrust. The lOG appear to form narrow but steeply dipping sedimentary troughs, while the Sukinda thrust appears to be steeply dipping to the south.
Cretaceous-Tertiary Boundary Events: The Fossil Vertebrate, Palaeomagnetic and Radiometric Evidence from Peninsular India
Authors: Sahni Ashok , Bajpai Sunil 
Published: November 2024

Abstract
Recent data based on microvertebrates and associated microfossils suggest that the Lameta and coeval formations of Peninsular India are younger (Maestrichtian) than ages previously assigned to them (Cenomanian-Turonian). Similarly, the Takli and their intertrappean correlatives in several localities have yielded dinosaurian elements indicating thereby a Cretaceous rather than Tertiary age. Furthermore, no exclusively Tertiary taxa has been recorded from these beds at Nagpur, Asifabad, Kachchh and adjoining areas. Samples collected for palaeomagnetic studies with reference to vertebrate-bearing horizons suggest that the Deccan basaltic activity was initiated in the Late Maestrichtian at the end of Lameta times. The major part of the eruption took place during the reversed magnetic chron, 29R, which encompasses the Cretaceous-Tertiary Boundary. Radiometric dates (K/Ar, 40Ar/39Ar) tend to cluster in a 60 m.y. 70 m.y. interval. The Deccan traps have been cited as a possible alternative source of Ir enrichment in comparison to the hypothesis which ascribes the anomalously high values of this element at the KTB to an extra-terrestrial impact. The gradual decline of dinosaurs as well as other marine plankton and benthos towards the close of the Cretaceous favours hypotheses that do not advocate 'instantaneous' global mass extinctions.
The Effect of Conrad on Regional Gravity Interpretations
Authors: Ramakrishna T. S. 
Published: November 2024

Abstract
When the regional Bouguer gravity anomalies do not corroborate with the surface geology, the general tendency of many interpreters is to take recourse to the undulations in the Moho, ignoring the Conrad in between, inspite of the fact that Conrad has been traced in several parts of the country by DSS as well as by gravity. Further, while inferring basic intrusives to explain some of the gravity highs, the corresponding magnetic data is also not taken into account. This note shows how Conrad may be creating disorder in regional gravity interpretations and how ignoring magnetic data leads to weak and suspect inferences.
Geometrical Analysis of Two Dimensional and Three Dimensional Oscillation Ripples
Authors: Das Subhasish 
Published: November 2024

Abstract
Analysis of ripple geometries using known tabulated laboratory and field data shows that the geometry can be of three types, i.e., sand ripples, light sediment ripples, and oscillatory bed ripples, reflecting different effects of the fluid shear stress and fluid accleration on the bed sediments. It is shown that when the bed shear stress or the amplitude of the water particle relative to the sediment size is small, the resulting vortices are more regular with low turbulence intensity and the generated ripples are two dimensional. However when the bed shear stress is large, the resulting vortices are very irregular with high turbulence intensity and the generated ripples are three dimensional in character.
Foraminiferal Evidence for Sediments of Santonian Age Occurring on Baratang Island, Andaman, India
Authors: Rajshekhar C. 
Published: November 2024

Abstract
The paper incorporates systematic descriptions of ten planktonic foraminiferal species recovered from the ejected material of mud volcanoes active on the Baratang Island, Andaman. The species are Pseudotextularia browni Masters, P. carseyae (Plummer, Globotruncana aegyptiaca Nakkady, G. arca (Cushman), G. concavata (Brotzen), G. coronata (Bolli), G. fornicata Plummer, G. gansseri Bolli, G. renzi Gandolfi and G. schneegansi Sigal.
Appearance of Rugoglobigerina rugosa, Ventilabrella glabrata, Globotruncana concavata and simultaneous extinction of G. schneegansi indicate Santonian as a lower age limit of Cretaceous rocks on the Baratang Island.
Upper Cretaceous Dinosaur Eggs from New Localities of Gujarat, India
Authors: Mohabey D. M. , Mathur U. B. 
Published: November 2024

Abstract
New occurrences of well-preserved dinosaur eggs have been found in the Lameta sediments near Dohad in Panchmahals district, Gujarat. The new localities lie 90 km east of the well-known Balasinor-Rahioli belt, which has the distinction of being one of the few dinosaur nesting sites in the world. The dinosaur eggs are spherical and have nodose ornamentation. Two types of egg shells have been distinguished on the basis of their microstructure. The egg shelIs have affinity towards sauropod types and are comparable to those of Kheda Type-B.