bluuebunny/crossref_metadata_2025_split huggingface dataset:
On The Age of the Pondicherry Formation of Madras South India
Authors: Samanta Bimal K. 
Published: November 2024

Abstract
A sequence of three planktonic foraminiferal zones, the Globorotalia angulata Zone, Globorotalia velascoensis Zone and Globorotalia aequa Zone, is recognised in the Pondicherry Formation of South India. The G. angulata Zone includes the lower marlstone, the G. velascoensis Zone includes the algal limestone and the G. aequa Zone corresponds to the discocyclinid limestone and the upper marlstone. The lower zone is dated as Middle Palaeocene and the upper two as Upper Palaeocene. Thus, on planktonic foraminiferal evidence, the Pondicherry Formation is Middle to Upper Palaeocene in age.
A New Mammalian Fossil from the Lower Murree of Kalakkot, Jammu And Kashmir State, India
Authors: Khan Aijaz 
Published: November 2024

Abstract
The problem of age and environment of deposition of Murree rocks in the Tertiary stratigraphy of north-western Himalaya is under debate for more than fifty years. The age of Murree Series was regarded as Lower Miocene by celebrated geologists viz. Pilgrim (1912), Wadia (1928 & 1966), Gansser (1964) and others on the basis of Fatehjang fauna (Lower Burdigalian) occurring at the base of these rocks in Potwar Basin, Pakistan.
During the course of geological mapping in Kalakot area, the present author found a new species of Upper Eocene (?) rhinoceratoid. This is the first rhinoceratoid fossil recorded from the lower Murree of Jammu foot hills, and its identification has revealed that it has a close affinity with the Russian and American rhinoceratoids of Palaeogene age. This means that the well established unconformity representing a big gap between the Subathu and Murree sediments in Potwar Basin has certainly narrowed down east of Jhelum Syntaxis.
Distribution Coefficient (KDFe2+-Mg) of Orthopyroxene-Biotite and Garnet-Biotite Mineral Phases in Relanon to Equilibrium
Authors: Dhana Raju R. 
Published: November 2024

Abstract
Petrographic study of the granitic rocks of Chipurupalle-Razam area in Srikakulam district of Andhra Pradesh showed that biotite was formed either from orthopyroxene or garnet in reaction with potassium feldspar, under textural disequilibrium conditions. To test whether chemical equilibrium was attained during the formation of biotite, iron distribution coefficient (KDFe2+-Mg) in orthopyroxene-biotite and garnet-biotite mineral phases was considered. KD of orthopyroxene-biotite pair varies from 1.1 to 2.0, while that of garnet-biotite pair varies from 2.6 to 6.5. After considering the effects of temperature difference and of other elements on the distribution coefficient, the large variation in KD values in the area was mainly related to the chemical disequilibrium conditions which operated during the biotite formation. An examination of KD values from different areas showed that in a majority of orthopyroxene-biotite phases and in all garnet-biotite phases, biotite is Mg-rich while the coexisting orthopyroxene or garnet is Fe-rich; and this was explained by the principles of crystal chemistry.
Calc-Silicate Skarns from Chinnabantupalli, Srikakulam District, Andhra Pradesh
Authors: Bhattacharyya C. 
Published: November 2024

Abstract
Calc-granulites of Chinnabantupalli area, Srikakulam district were subjected to contact metasomatism by the injection of K-feldspar-forming fluid. This paper describes the mineralogy of the calc-silicate skarns, mineral chemistry of clinopyroxene and garnet, and emphasizes the textural aspects which have a bearing on the genesis of skarn minerals. The minerals like wollastonite, hornblende, biotite, epidote-clinozoisite-zoisite, a part of the scapolites, garnets and calcites were secondarily formed as a result of contact metasomatism. Most of the scapolites are suggested to be of regional metamorphic origin. The formation of wollastonite, other conditions remaining same, is shown to have been favoured by higher CaO/(FeO+MgO) ratio of these rocks.
Genesis of Lead-Copper Ores in Agnigundala Area Andhra Pradesh
Authors: Krishna Rao J. S. R. , Dhana Raju R. 
Published: November 2024

Abstract
Lead-Copper deposits in dolomites, cherty dolomites, quartzites, and calcareous quartzites occur at Bandalamottu, Dhukonda, and Nallakonda of Agnigundala area. The mineralization is mainly controlled by stratigraphic and lithologic features. Galena, sphalerite and pyrite are the dominant ore minerals in dolomites, while chalcopyrite and bornite are dominant in quartzites. Linnaeite, covellite, chalcocite, and bravoite are accessories. In addition to these, X-ray patterns show the presence of violarite, cobaltite, niccolite, stibnite, meneghinite, sternbergite, penroseite, and cuprobismutite. Malachite and azurite are the liberation products of chalcopyrite and bornite during oxidation.
The field and mineralogical associations, textural, petrographic and petrochemical features show that Pb, Zn, and Fe sulphides represent a primary sedimentary genesis, subsequently metamorphosed and recrystallized, while copper mineralization is due to later hydrothermal activity. The presence of linnaeite and bravoite indicates low temperature of the order of 300°C and below, low pressure, and low oxidation for the ore formation.
Geochemistry of Granite-Greenstone Terrain of South India
Authors: Sreenivas B. L. , Srinivasan R. 
Published: November 2024

Abstract
A critical evaluation of the available major and trace element data on rocks of the granite-greenstone belts or South India leads to the following inferences: Barrovian and Abukuma facies series of metamorphism are recognizable in the terrain. Rocks of peridotitic and basaltic komatiite affinities occur in the pre-Dharwar and early Dharwar ultramafic-mafic sequence. The bulk of the greenstones are island arc tholeiites with a strong calc-alkaline affinity. The presence of detrital pyrites in the oldest conglomerates, and the occurrence of red beds in the topmost Dharwar sequence, indicate that an oxygenic atmosphere evolved through the Dharwar times. The pre-Dharwar granitoids were probably tonalitic, and through time, alkali fractionation gave rise to the Champion gneisses, Peninsular gneisses and Closepet granites. The available data are inadequate to elucidate the fractionation pattern of the granitic crust of Peninsular India.
Pyrolite and eclogite mantle are invoked for tectonomagmatic events during the pre-Dharwar and Dharwar times, respectively. Convection, and eclogite sinkers, are proposed as alternative geodynamic models.
From the geochemical evolution, it is contended that the granite-greenstone belts of Peninsular India represent a more evolved crustal condition as compared to the Archaean granite greenstone belts of South Africa and Western Australia. Obviously, the granite-greenstone belts of all the shield areas, did not evolve simultaneously.
Some New Approaches to Geochemistry of Precambrian Hydrothermal Ore Deposits in India
Authors: Raymahashay B. C. 
Published: November 2024

Abstract
Recent field data on hydrothermal ore deposits and experimental data on solution chemistry of minerals and dissolved species have been applied to certain Precambrian ore deposits of India. Parameters of the environment of ore deposition like temperature, fugacity of gases and concentration of dissolved species have been calculated from selected mineral assemblages. Possible lines of future research have been suggested and gaps in the present knowledge pointed out .
Geochemistry of Precambrian Carbonatite Complexes of India: Present Status of, and Gaps in our Knowledge
Authors: Udas G. R. 
Published: November 2024

Abstract
Carbonatites of Precambrian age occur at Newania and Mundwara in Rajasthan, Sevathur and Hogenakal in Tamil Nadu, Kunavaram in Andhra Pradesh, and KolJegal in Karnataka. The Newania carbonatite is 959±24 m.y. old (K-Ar age of an alkali amphibole), and the Sevathur carbonatite is 720±30 m.y. old (K-Ar age of a biotite). Although comprehensive geochemical studies involving major, minor, and trace elements and carbon, oxygen and strontium isotopes have been undertaken on the 37.5±2.5 m.y. old Eocene carbonatite complex at Amba Dongar, Gujarat, geochemical studies on the Precambrian carbonatites of India have been confined only to routine determinations of selected elements like Sr, Ba, Y, Ce, La, Nb, Zr, Th, Mn, Ti, F and P to demonstrate their carbonatitic affinites. Except for two K-Ar ages, and for some limited trace element data, no attempts have been made to elucidate the chronologie and petrogenetic evolution of these Precambrian carbonatites by the application of Rb-Sr, K-Ar, and U-Pb geochronometry, critical element ratios, stable and radiogenic isotope abundances, and geothermometry. Basic researches aimed at formulating geochemical criteria for locating commercially exploitable economic Precambrian carbonatite complexes are yet to be initiated in India.
The Mayurbhanj Granite - A Precambrian Batholith in Eastern Inola
Authors: Saha A. K. 
Published: November 2024

Abstract
The term 'Mayurbhanj Granite' is proposed here for a batholithic body of biotite-amphibole-(stilpnomelane) granite grading to alkali-feldspar granite which covers nearly 1000 sq. km area in the northern part of Mayurbhanj district, Orissa. The batholith shows intrusive relationship with the adjoining Singhbhum Granite, Dhanjori Group gabbro-anorthosite and the Singhbhum Group metamorphites, and is made up of three units which were successively emplaced within the same magmatic cycle: (a) fine-grained, homophanous biotite-ferrohastingsite (-stilpnomelane) microgranite, in part granophyric, (b) coarse-grained, homophanous to well-foliated ferrohastingsite-biotite granite, which is porphyroblastic and gneissos in the east, and (c) 'biotite aprogranite injections within the porphyroblastic gneisses in the east. The second unit is by far the largest and was intruded synkinematically with respect to the second-generation folding in the Singhbhum Group metamorphites, probably about 1.1 × 109 years ago.
Mineralogy of an Unusual Alteration Product of Kyanite from Karnataka, India
Authors: Ramakrishnan M. , Narayanan Kutty T. R. , Anantha Iyer G. V. 
Published: November 2024

Abstract
An alteration product of kyanite from Kudinirkatte near Holalkere, Karnataka State, is found to be a hydrous alumino-silicate with a chemical composition corresponding to that of muscovite. Thermal, X-ray diffraction, and infrared spectral data show distinct variation from the known polymorphs of muscovite. On hydrothermal reactions with potassium-rich solution, the alteration product converts to 1M muscovite, and in sodium-rich solution, it converts to a mixture of muscovite and paragonite. When seeded, it converts to 2M muscovite at a higher temperature and pressure. The alteration product of kyanite has a 1M muscovite structure with randomly distributed montmorillonite domains.
Inference of Granitic Batholiths by Gravity Studies in South India
Authors: Krishna Brahmam N. , Kanungo D. N. 
Published: November 2024

Abstract
Three well-defined gravity 'lows' in Kodaikanal, Gudalur and Erode regions are explained as due to granitic batholiths at depth. The scattered outcrops of granitic bodies exposed in these regions are suggested to be interconnected at depth, and, therefore, are merely the surface expressions of the three concealed batholiths. Although the exposures of the individual granitic bodies in the Kodaikanal-Coimbatore region are elongated in an east-west direction, it is surmised, from structural evidences, that the main batholith is elongated in a roughly NNW-SSE direction.
A striking correspondence between the isoseismals for the Coimbatore earthquake of February 8, 1900 and the gravity contours is noticed. It is suggested that the Coimbatore earthquake (and the reported seismicity near Kottayam and 'Palghat Gap') could be the result of some minor readjustments of the boundaries of the batholith along fault planes.
Petrographic Characters of Coals from Makum Coalfield, Assam
Authors: Mukherjee B. C. 
Published: November 2024

Abstract
High sulphur coals from Makum Coalfield, Assam, give an interesting petrographic assemblage, the maceral vitrinite forming around 90 per cent of the constituent macerals. Separation of the macerals Vitrinite, Fusinite, Exinite and Micrinite is attempted by gravity separation technique and concentration of these macerals; of good petrographic purity, is obtained. Chemical analyses of the macerals thus separated, reveal among other things (regarding rank etc.) the presence of sulphur dominantly in the Exinite group. From this observation, the removal of sulphur of these coals is visualised.
Evolution of Peninsular Gneiss Restraints, Reasons and Reflections
Authors: Srinivasan R. , Sreenivas B. L. , Krishna Rao B. 
Published: November 2024

Abstract
Peninsular Gneiss' is a product of syntectonic remobilization of some sialic basement (Fundamental gneiss?) with reference to Dharwar folding. The preservation or obliteration of the basement relation with respect to Dharwars is a function of varying degrees of remobilization characteristic of low pressure and high pressure metamorphic belt regions of Karnataka. By remobilization the basement highs within the schist belts were transformed to mantled gneiss domes, and tonalites were made over to granodiorites and adamellites. With a common source of heat, accompanying the remobilization, retrogression of high grade metamorphic rocks of older' Sargur Supergroup' and prograde metamorphism of volcanics and sediments of 'Dharwar Supergroup' were accomplished.
Source and Fixation of Nickel in the Nickeliferous Limonite Profile of Sukinda Valley, Orissa
Authors: Chakraborty K. L. , Chakraborty Tapan Lal 
Published: November 2024

Abstract
Nickeliferous limonite occurs over a wide area above tbe serpentinized ultramafic rocks of Sukinda Valley (85°45'E: 21°4'N - 85°52'E: 21°4'N), Orissa, India. It is overlain by a thin mantle of laterite, and is itself underlain successively by silicified ultramafics and serpentinites with layers of chrornitite, followed by unaltered or partly altered dunite-peridotite. Nickeliferous limonite profile extends from 1.22 metres up to 7.0 metres on an average below the laterite cover. NiO content in limonite varies from 0.32 to 1.17 per cent; in the primary ultramafic rocks (e.g., dunite-peridotite) from 0.44 to 0.75 per cent, and in the chromitite from 0.13 to 0.40 per cent. Thin laminations of the chromite layers are preserved in the limonite on the hanging and foot-wall sides, indicating its formation in situ. No separate nickel mineral was identified.
It is concluded that nickel was fixed in the lattice positions of olivine and chromite in dunite-peridotite and chromitite respectively. The element was released during breakdown of these minerals by residual weathering, and was precipitated in the limonite profile at the base of the laterite mantle in an acid environment.
The Living Foraminifera of Dummulapeta Creek East Coast of India
Authors: Venkata Rao T. , Subba Rao M. 
Published: November 2024

Abstract
Dummulapeta Creek is a marginal marine environment near Kakinada, east coast of India. The foraminifera as well as seasonal variations in their abundance and distribution in the creek have been investigated in relation to different ecological factors like salinity, temperature, pH, and dissolved oxygen of waters in contact with the sediment, and texture and organic matter content of the sediments.
Fifty-six species of foraminifera have been identified from the creek. Of these, 33 species were never found in living condition in the creek. Of the remaining 23 species represented by living individuals, only QuinquelOculina seminulum, Ammonia beccarii, A. tepida, A. dentatus, and Miliammina fusca var. occur abundantly in the creek. These species seem to reproduce in the creek in December under relatively low temperature and salinity conditions.
The Bauxite Deposits of Anantagiri, Visakhapatnam District, Andhra Pradesh
Authors: Ramam P. K. 
Published: November 2024

Abstract
Bauxite forms cappings at altitudes varying from 1090 to 1445 m above mean sea level, over the garnet-sillimanite gneisses near Anantagiri in Visakhapatnam district, Andhra Pradesh. Major cappings occur on Galikonda, Raktakonda, Katuki and Chittamgondi hills while those near Kottavalasa are relatively small. Bauxite is either light to dark brown or pink in colour and moderately hard with crystalline gibbsite occuring in varying proportions. The average thickness of bauxite in the various cappings may range between 3 and 15 m, while the maximum thickness encountered is about 50 m on Galikonda. A typical profile of the bauxite residuum in the area consists of a lateritic bauxite underlain by partially lateritised khondalitic gneiss or lithomarge followed by kaolinised and unaltered khondalitic gneiss. These bauxites are low in silica and titania and relatively high in iron oxide when compared to those derived from the Deccan basalts. The development of bauxite over the sillimanite rich gneisses, relict foliation, pseudomorphs of gibbsite after sillimanite, garnet and felspar, and the unaltered partings of the bed rock within the bauxite residuum, reveal that these bauxites' are formed from tbe in situ transformation of the subjacent garnet-sillimanite gneiss (khondalite). While the lithology and physical properties of these gneisses are congenial for lateritisation/bauxitisation on a regional scale, the preservation of some of the cappings with remarkable thickness may be attributed to a favourable structural setting. It is surmised that these bauxites are of post Mio-Pliocene age.
Geochemistry of Subsurface Hornblendic Rocks from Kolar and the Archaean Crustal Composition of the Peninsular Shield
Authors: Divakara Rao V. , Venkatnarayana B. , Ramana Y. V. 
Published: November 2024

Abstract
Major and minor elemental analyses of the subsurface hornblendic schists, granulites and basalts from the Kolar schist belt, India (a Precambrian schist belt), suggest that the crust was mostly basic in the Archaean times and similar to tholeiitic basalt.
Implication of the Mobile Belt of the Indies Archipelago on the Concept of Continental Drift Between India and Australia
Authors: Karunakaran C. , Ray K. K. , Saha S. S. 
Published: November 2024

Abstract
The Indies mobile belt stretching from northern Burma through the Indonesian to the Australasian archipelagoes is essentially Upper Mesozoic-Cainozoic in age. It is intercontinental in a sense that it is situated between the continents of India and Australia on one side and Sino-Sunda continent on the other, but essentially intracontinental because subsurface continuity of the continental mass and pre-geosynclinal sedimentary formations can be envisaged between the two sectors of continental mass below the geosyncline.
Studies of the geology of the various parts of the Indonesian mobile belt especially the transverse vertical gelogical cross sections of various segments of the belt in Assam-Burma, Andaman-Nicobar, Mentawal-Sumatra and Australasian sectors, suggest spatial continuity of the continental crust and pre-geosynclinal geological formations below the Upper-Mesozoic-Cainozoic geosynclinal formations of the mobile belt.
Absence of any imprint on the Indonesian mobile belt expected due to continental drift between India and Australia corroborates the view of the non-existence of such continental drift.
Occurrence of Fossil Lion and Spotted Hyena from Pleistocene Deposits of Susunia, Bankura District West Bengal
Authors: Dutta Arun Kumar 
Published: November 2024

Abstract
The note records the occurrence of fossil lion, Panthera cf. leo, and spotted hyena, Crocuta cf. sivalensis, in the Pleistocene alluvial deposits near Susunia in Bankura district West Bengal. This is the first definite record of fossil lion from India, and that of C. cf. sivalensis from any Pleistocene deposit in Peninsular India. The fossils are described and their distribution is briefly discussed,
A Contribution to the Geology of Lansdowne Area, Garhwal Himalayas, India
Authors: Gupta L. N. 
Published: November 2024

Abstract
Lansdowne granite gneiss shows a tectonic contact with the underlying Lansdowne metamorphites. The metamorphites show repeated and superposed progressive regional metamorphism. Three phases of deformation and folding are noticed. The rare assemblage, chloritoid, staurolite, kyanite, andalusite and quartz is present in the area.
Granite is metamorphosed into augen gneiss, mylonites and phyllonites. Muscovitisation, tourmalinisation and greisening indicate chemical alteration in the granitic rocks. Textural features are correlated with deformation and folding.
Diagenesis of the Dark Grey Limestone of Nagod Formation, Madhya Pradesh
Authors: Srinivasa Rao K. , Ghosh D. B. , Chamanlal  
Published: November 2024

Abstract
The rocks of the Vindhyan supergroup show evidences of deposition in a shallow marine environment, the depositional basin being similar to 'epeiric sea'. The dark grey limestone unit of the Nagod Limestone Formation is a low magnesian limestone and is invariably an intrasparite or oosparite with variable amounts of authigenic cement spar, neomorphic spar and micrite occupying intra- and inter-allochemical pore spaces. Fibrous nonferroan calcite, dog tooth fringe of nonferroan calcite, drusy mosaic of ferroan calcite and syntaxial rim cement, constitute the different types of cements noticed. Authigenic minerals like dolomite, quartz, plagioclase and pyrite are present in small quantities. Based on the precipitational and recrystallisation fabrics of the calcite and the presence of different authigenic minerals, the diagenetic history of the limestone is worked out.
A Comparative Study of the Geochemistry of Zinc and Cadmium in the Skaergaard Intrusion
Authors: Dissanayake C. B. 
Published: November 2024

Abstract
Being group lIb elements, both Zn and Cd show similar chemical properties. The chemical analysis of a suite of rocks and separated minerals from the Skaergaard intrusion, East Greenland has enabled a detailed comparison to be made of the geochemistry of Zn with that of Cd.
Both Zn and Cd show an affinity for ferromagnesian minerals, A study of their mode of entry into structural sites however, points to the fact that while Zn shows a definite preference for Fe2+ sites in all the minerals studied, Cd shows a lesser tendency to substitute for the Fe2+ sites, except in the case of pyroxene. While Zn shows a very weak tendency to substitute for Ca2+ sites, Cd displays a much stronger affinity for the Ca2+ sites.
Regional Magnetic Investigations in the Coastal Tract East of North Cuddapah Basin
Authors: Bhaskara Rao V. , Narasimha Swamy G. 
Published: November 2024

Abstract
Three magnetic profiles were laid across the coast, east of North Cuddapah basin. Three subsurface ridge systems were inferred and related to the rejuvenation of the Eastern Ghats and the great east to west compressional forces during the Cuddapah orogeny. The extension of the Gondwana basins belween the ridges in the coastal tract is examined and discussed.