bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Reinterpretation of the Geological History of the Singhbhum Shear Zone, Bihar
Authors: Banerji A. K. 
Published: November 2024

Abstract
The Singhbhum shear zone represents a deep seated fracture that probably extended up to the upper mantle through which basic rocks poured out continuously and extensively together with some ultrabasic rocks. The northern block gradually subsided and received sediments interlayered with basic rocks and tuffs, with a conglomerate horizon at tbe base. Subsequently the movements were reversed along the line of fracture and it was transformed into a zone of shearing within which migma-magma activity and mineralisation took place. Residual stresses within the shear zone were released through wrench faulting after which the shearing movements resumed locally and continued even up to recent times at some places.
Studies on Some Granitic Rocks of Palni-Dindigul Area, Tamil Nadu
Authors: Narasimha Rao P. 
Published: November 2024

Abstract
The temperatures of formation of some granitic and charnockitic rocks from parts of Palni-Dindigul area have been determined by the felspar geologic thermometer. Two distinct ranges of temperatures are indicated among the rocks on the basis of which they are classified. Their petrogenesis is discussed on the evidences furnished by the temperatures, field relationships, twin laws of plagioclases and some significant petrographic characters. The older grey granitic rocks are of metasomatic origin and were probably products of synkinematic granitization while the pink perthite-quartz granites represent later magmatic intrusions. Among the charnockites also, two different types are recognized. One is formed by the charnockitization of the gneisses, while the other represents a magmatic type of charnockite.
Seasonal Variations in Foraminiferal Abundance and their Relation to the Substrate in Vellar Estuary, Madras
Authors: Ramanathan Rm. 
Published: November 2024

Abstract
Seasonal differences in the abundance of the benthic Foraminifera of the estuary are shown to be related to the standardized nomenclature of the sediment types relative to sand silt and clay.
The area with almost sandy substrate in November 1967 yields the lowest foraminiferal number due to the strongest currents caused by the floods observed in October 1967. The finest sediments and weaker currents are associated with the higher foraminiferal numbers in March and April 1968.
The most accommodative substrate for a higher foraminiferal number is found to be silty-clayey-sand, in which silt is dominating over clay.
Sedimentary Structures and Paleocurrent Analysis of the Barakar Sandstone in Chirimiri (Kurasja) Coalfield, Madhya Pradesh
Authors: Casshyap S. M. , Jain R. K. 
Published: November 2024

Abstract
The Barakar sandstone of Chirimiri (Kurasia) coalfield includes complete or truncated sedimentary cycles, some of which commence with pebbly gritty coarse sandstone and, fining upwards through coarse cross bedded sandstone, end up with carbonaceous siltstone or coal seam. Among the primary depositional structures, ripple drift, trough and tabular cross bedded sets and cosets are common. These structures have been described from the genetic and hydrodynamic viewpoints. Erosional structures occurring in the sandstone include channels, scour-and-fill, potholes and flute casts.
A paleocurrent analysis based on 88 cross bedding azimuths reveals the preponderance of two depositional current systems - the main current system which flowed from southeast, and a tributary system flowing from east-northeast. An increase in cross bedding variability at higher sampling levels reflects the meandering behaviour of depositing currents.
A sedimentary analysis of the sandstone sequence suggests that the Barakar sedimentation in this coalfield was controlled, perhaps right from the beginning, by periodic tectonic uplifts of the granitoid landmass located to the east and southeast. It is suggested each tectonic uplift resulted in the deposition of a fining-upwards fluvial cycle.
Recognition, Correlation and Age of Erosion Surfaces in the Iron Ore Ranges of Bihar and Orissa
Authors: Ramana Rao K. L. V. , Vaidyanadhan R. 
Published: November 2024

Abstract
In the Iron Ore Ranges of Bihar and Orissa, three erosion surfaces have been recognised around 3000-2700 feet, 2300-2000 feet and 1600-1400 feet above M.S.L., based on model studies in the laboratory, and the relative positions in the field of the residual deposits of laterites and lateritic iron and manganese ores. These have been correlated with those in the neighbouring areas in the southeastern Chota Nagpur and the Simlipal massif in Bihar and Orissa respectively. Based on the study of sedimentary record in the adjoining Bengal Basin, the tentative ages assigned to them from the top are Upper Jurassic to Lower Cretaceous, Upper Eocene and Upper Miocene.
Algal Stromatolites from the Kaladgi (Precambrian) Formations, Near Alagundi, Bijapur District, Mysore State
Authors: Viswanathiah M. N. , Chandrasekhara Gowda M. J. 
Published: November 2024

Abstract
Occurrence of stromatolitic colonies has been observed in variegated limestones around Alagundi, and they are termed as 'algal stromatolites'. Depending upon the morphological similarities, four different forms have been recognised and their salient features described. Natural environmental factors that prevailed during their formation have been enumerated, and diminution of algal filaments into fine micrite is also discussed.
Evolution of the Drainage of Cauvery in South India
Authors: Vaidyanadhan R. 
Published: November 2024

Abstract
It is now realised that the course of the river Cauvery in South India as observed is different from what it was during its inception during late Cretaceous or early Tertiary times. The upper part of the course over the Mysore plateau might have had only slight modifications both headward as well as laterally; but the lower part from Sivasamudram appears to be quite different.
The vast flood plain of Palar, negligible flow even during flood times, the long and broad NE-SW trending dry valley from around Pennagaram in the south to Vaniyambadi in the north extending for about a distance of 65 miles in Tamil Nadu, southeast of Mysore plateau, require satisfactory explanation. It is suggested that the lower part of the Cauvery (Proto-Cauvery) flowed from Hogenakal, through the above valley on to the present course of the Palar river, and that the changes in the course of the rivers in this region were brought about during the Tertiary times, mainly aided by headwa(d erosion by tributaries along fracture zones and fault zones in the region.
Deep Main Faults in South India
Authors: Grady John C. 
Published: November 2024

Abstract
A system of deep, main faults containing carbonatite complexes and ultra basic to alkaline intrusions occurs in South India. The faults strike in a northeast-southwest direction across the Peninsula, and two main sets have been recognised at N 30°E and N 45° E. They occur in a block-faulted region in which some of the uplifted blocks form hills up to 2900 metres high and grabens have been downfaulted to as much as 1700 metres below sea level. Seismic records since the year 1800 show that the majority of earthquakes in the Precambrian Shield of South India are concentrated along one of the fault zones which is also the location of igneous intrusions, hydrothermal veins, pegmatiles and metasomatism. A positive gravity anomaly underlies this zone.
Minerals of economic importance occur in some of the intrusions. The most productive artesian wells drilled by the United Nations Groundwater Project in Tamil Nadu are located on one of the major faults of the system. It is thought that continued exploration with the aid of photogeology and geophysical surveys will reveal more of the deep, main faults, and possibly more ore bodies, in South India.
Reconnaissance Survey of the Quaternary Geology of the Cauvery Delta
Authors: Meijerink A. M. J. 
Published: November 2024

Abstract
The exposed Quaternary geology of the Cauvery delta has been mapped from aerial photographs. The study has been complemented by a series of augerings in the northern part-of the delta. The grain size distribution of Holocene deposits, consisting of natural. levee complexes, backswamps, coastal ridges and low lying areas under tidal and back-water influences have been studied. With the aid of subsurface data it has been attempted to reconstruct the Post-Tertiary development of the delta. The relative chronology of the formations could be established.
Eustatic curves are discussed briefly in the context of their applicability to the Indian subcontinent and they have been used for a provisional dating of various Holocene deposits. A late Pleistocene to early Holocene transgression was followed by delta formation in the south. Subsequently the main fluvial deposition shifted towards the north. Since the Atlantic period, a series of beach ridges were formed along the coast. Transportation of sands and finer material by long shore currents has resulted in the formation of a cuspate foreland on the southern part of the delta. Three marine stages in the cuspate foreland have been correlated with fluvio-marine stages in the north.
New Mammals from Murree (Kalakot Zone) of the Himalayan Foot Hills Near Kalakot, Jammu & Kashmir State, India
Authors: Ranga Rao A. 
Published: November 2024

Abstract
A new genus, including two species, of the Artiodactyl family (?) Choeropotamidae from the Murree group, is described. These are the first mammalian fossils known from the Murree outcropping within the present day limits of Indian territory.
Mineralogy, Chemical Characters and Genesis of the Chromite Deposits of Moulabhanja Area, Dhenkanal District, Orissa
Authors: Chakraborty K. L. , Mallik A. K. 
Published: November 2024

Abstract
Pockets of 'sack-form' chromite deposit occur at the intersection of dykes of olivine gabbro near Moulabhanja hills in the Dhenkanal district of Orissa. The dykes intruded the Precambrian granite-gneiss belonging to the Eastern Ghat orogenic belt. Chromite also occurs as minor accessory in olivine gabbro; and in this respect differs in its mode of occurrence from chromite deposits associated with the dunite-peridotite of the Iron ore orogenic cycle. The close association of chromite with olivine gabbro, the paragenetic sequence of the minerals in the rock, and the mineralogy, texture and chemical nature of the ore, suggest that the chromite melt was separated from the basic (olivine gabbro) magma as an immiscible liquid fraction and crystallized earlier than the silicate minerals.
Gondwanaland and the Growth of India
Authors: Crawford A. R. 
Published: November 2024

Abstract
New palaeomagnetic data clarify the manner of break-up of Gondwanaland and show that India was adjacent to Africa and Antarctica, but not Australia, during the Phanerozoic. This does not conflict with possible contiguity of parts of India and Australia before Gondwanaland came into existence.
Relative movement of the pole and a Gondwanaland which is known to have existed at least from the Cambrian to the time of break-up in the late Mesozoic implies non-synchroneity of glaciations geographically distant from one another, the products of which have also been scattered by drift. Precambrian tillites are unlikely to be synchronous; glaciations merely follow the poles.
A difference is established between the Indian peninsula. the Indian shield and Gondwanic India. The development of India has been in five stages; before Gondwanaland existed, during its life-span, during association with Madagascar while separate from Africa, during movement as Gondwanic India, and since collision and fusion with Asia.
Late Pleistocene Gastropods from Nalagarh Tehsil, Himachal Pradesh
Authors: Bhatia S. B. , Mathur Anil K. 
Published: November 2024

Abstract
Six gastropod taxa from a late Pleistocene terrace of the river Sirsa are described. These include three new species belonging to the family Pupillidae. The palaeoecological implications of the fauna are also discussed.
Petrography and Origin of the Krol Sandstone around Solon, Himachal Pradesh
Authors: Bhattacharyya Ajit , Chanda S. K. 
Published: November 2024

Abstract
Earlier studies on the geology of the Krol Belt in general have included little detailed information pertaining to the petrology and mineralogy of the Krol Group. The work reported herein represents a part of a comprehensive petrological study of the Krol Formations and provides information mainly about the petrology and probable environment of deposition of the basal unit of the Krol Group, namely the Krol sandstone, that overlies the Infra-Krols.
The Deformation of the Bar Conglomerate
Authors: Murty T. V. V. G. R. K. , Bhargava L. R. 
Published: November 2024

Abstract
The basal Delhi conglomerates seen at Bar are reputed for the intense deformation seen in them. Heron's memoir on central Rajputana contains a brief description of these conglomerates.
The pebbles in the conglomerate are mostly made up of quartzites. They vary in size from small pebbles to large cobbles. The percentage deformation in the long axes of the pebbles is around 175, and in some extreme cases about 700. The pebbles lie in the cleavage/bedding surface with their long axes almost parallel to each other. The long axes are coincident with the true dip of cleavage surface.
The overall matrix of the conglomerate is psammo-pelitic and consists of sharply alternating psammite and pelite layers. A strong cleavage is seen in the matrix which is parallel to the bedding.
The pebbles are in all cases flattened and elongated. A two stage deformation model in which an early phase of flattening followed by flow is suggested for the pebbles in the conglomerate.
Job Charnock and Charnockite
Authors: Pichamuthu C. S. 
Published: November 2024

Abstract
Job Charnock was an officer of the East India Company in Bengal due to whose initiative the British were able to acquire Calcutta. He died in 1692 and his tombstone is found in a mausoleum in the compound of St. John's Church. Holland discovered that this tombstone was made of the hypersthene-bearing rock occurring rear Madras and whose petrology he was investigating at that time. As this was a new type of rock, Holland suggested for it the name Charnockite in honour of Charnock, the Founder of Calcutta.
In this paper, a description is given of the mausoleum, the tombstone and the epitaphs on it. The life, career and character of Job Charnock are briefly outlined.
Palaeomagnetism and Geological Correlation of Certain Precambrian Formations of Andhra Pradesh
Authors: Prasad C. V. R. K. , Damodara Reddy V. 
Published: November 2024

Abstract
The magnetic studies on the ferruginous sandstone samples from the Kaverisamudram area and the metamorphosed shales from Beduduru area of Cuddapah basin are presented here along with the results from the dykes near Tirupati. From a comparison of these results with those obtained from other Precambrian formations of India, it is found that the Bijawars are equivalent to Cuddapahs. The results from the metamorphosed shales have indicated that the igneous activity in Cuddapah basin was contemporaneous with sedimentation. This igneous activity is also found to be contemporaneous with one of the intrusive phases of the Tirupati area.
Differentiated Hypersthene-Olivine Dolerite Dyke near Harohalli, Mysore State
Authors: Sadashivaiah M. S. , Ikramuddin M. 
Published: November 2024

Abstract
Textural, mineralogical and petrochemical variations observed across the width of the differentiated hypersthene-olivine dolerite dyke situated near Harohalli have been described and discussed. The salient features of the dyke are (i) the occurrence of mafic minerals rich in iron, and plagioclase less rich in anorthite content at the borders, with a progressive decrease of iron content in the mafic minerals and increase in anorthite content of the plagioclase towards the central zone and (ii) the textural variation from the flow and hyalopilitic at the margins, intersertal, intergranular, ophitic and subophitic at the intermediate zones and poikilitic at the centre. The chilled margins show a higher content of iron, alkalies and silica and a lower content of MgO, CaO and Al2O3. than the central portion. These characters indicate that the differentiation is due to thermodiffusion as described by Wahl as the observed features cannot be explained by any other known mechanisms of differentiation.
Overthrusting and Emplacement of Basic Rocks in Lesser Himalaya, Garhwal, U. P.
Authors: Jain A. K. 
Published: November 2024

Abstract
The metamorphosed basic rocks, probably emplaced along dislocation zones during overthrusting and facilitating such movements, are persistent at the base of Uttarkashi thrust sheet in the Precambrian-Lower Palaeozoic rocks of innermost Lesser Himalayan region of Uttarkashi, Garhwal. Marked absence of such basic rocks in Tertiary rocks, and along thrusts of Sub-Himalaya and outermost Lesser Himalaya in Garhwal, may be taken as indicating a probable Upper Cretaceous age for these intrusives related to the initial phase of Himalayan orogeny.
Petrology of Picrodolerites from the Dedan Cluster, Gujarat
Authors: Krishnamacharlu T. 
Published: November 2024

Abstract
Picritic dykes of oceanite and ankaramite composition occur around Dedan in the Kathiawar peninsula of Gujarat State. They have been studied across their width, with reference to the distribution and crystallisation of olivine and pyroxene. Olivine and pyroxene occur both as large phenocrysts and as small crystals in the groundmass. Considerable variation in the concentration of olivine and pyroxene is observed from the central portion of the dykes to the margins. A gradual decrease in the grain size and content of these minerals is seen from the centre to the margin of the dykes It is also observed that the grain size of these two minerals shows a direct relationship with the percentage of these minerals. This is explained by flow differentiation proposed by Bhattacharji and Smith for the Muskox feeder dyke.
Geology of the Jensurigudda Iron Ore Deposit of Chickmagalur District, Mysore
Authors: Mishra R. N. 
Published: November 2024

Abstract
The Jensurisudda Iron ore deposit is one of the prominent iron ore occurrences in the Bababudan hills of Mysore State belonging to the 'Bababudan Series' of Dharwarian age.
The formation consists of bedded hematite and limonite resting over ferruginous shale with lenses of quartzites. The structure is a major fold with axis trending NNWSSE. The harder rocks viz. the quartzites and the ores display innumerable irregular folds. Structural control or localisation is present in a broad sense. Harder or lumpy ore overlies softer ore and blue dust. The ore body extends to a depth of 20 metres. It is inferred that the ferruginous shales are the source rocks for ore formation and that the concentration has been achieved through 'lateritic weathering'.
Petrogenetic Significance of Zn Distribution, and of Zn/Fe, Zn/Pb Ratios in Granitic Biotites
Authors: Viswanathan S. 
Published: November 2024

Abstract
The zinc content of biotite is a potentially useful petrogenetic tracer to determine if a granitic pluton formed by magmatism (crystallization-differentiation), metasomatism, or anatexis. This conclusion stems from a geochemical study of Zn distribution, and of Zn/Fe, Zn/Pb ratios in granitic biotites from the 2.7 billion year old Giants Range batholith of northeastern Minnesota, U.S.A. Results show that the zinc contents of biotites from metasomatic granitoids (477 ppm), anatectic tonalites (498 ppm) and their parent metasedimentary rocks (498 ppm) are significantly lower than those characterizing magmatic granites (754 ppm) and magmatic leucogranites (943 ppm). Also, in a magmatically fractionated series of granit c rocks, the Zn contents and Zn/Fe ratios of biotires increase progressively in the sequence tonalite-granodiorite-adamellite-graniteleucogranite, whereas the Zn/Pb ratios decrease.
Gondwana Pebble-Slate in the Rangit Valley Tectonic Window, Darjeeling Himalayas and its Significance
Authors: Roy Subimal Sinha 
Published: November 2024

Abstract
To the south of the Central crystalline zone of the Darjeeling Himalayas, in the interior parts of the frontal zone of the nappes, a sequence of the Lower Gondwana rocks occurs in a window, overlain by the tectonic cover of the Daling-Darjeeling group of metamorphites. A prominent marine fauna bearing pebble-slate horizon is developed at the base of this sequence. The stratigraphy and lithologic characters of this horizon are described in detail, and are considered significant in the context of the palaeogeography and tectonic evolution of this part of Himalaya.
Skull Characters of Crocodylus biporcatus, Cuvier
Authors: Badam C. L. 
Published: November 2024

Abstract
The paper gives a detailed morphological account of the skull of Crocodylus biporcatus Cuvier, collected from the Pinjor Stage of the Upper Siwaliks and housed in the museum of the Centre of Advanced Study in Geology, Panjab University, Chandigarh. The species is a synonym of the salt water crocodile, C. porosus Schneider inhabiting India and Malaysia. The present attempt to study this species in India would be the second one after Falconer and Cautley gave the first account of the form in 1836.
Stratigraphy and Microfauna of the Eocene Beds of Rajasthan
Authors: Khosla S. C. 
Published: November 2024

Abstract
Stratigraphic successions of the Eocene beds of Rajasthan are described from four localities, three in district Bikaner and one in district Jaisalrner. A total of one hundred twelve species of microfauna, comprising thirteen larger foraminifers, forty-four smaller foraminifers and fifty-five ostracodes are recorded. The Eocene beds are divided into two formations, the lower Khuiala and the upper Bandah. On the basis of the larger foraminifers and pelecypods which occur dominantly, the Khuiala Formation is subdivided into six assemblage zones: Zone 1-Assilina granulosa zone, Zone 2-A. daviesi zone, Zone 3-A. lacunata zone, Zone 4-Venericardia mutabilis zone, Zone 5-Assilina sp. zone, Zone 6-Barren zone, and the Bandah Formation into two assemblage zones: Zone 7-Discocyclina sella zone, Zone 8-Nummulities maculatus/Discocyclina dispansa zone. While a more or less complete and comprehensive succession of the Eocene beds, represented by zones 1-8, occurs at locality I , only zones 1 and 2 occur at localities II and III, and zones 3-5, 7 and 8 occur at locality IV. The Khuiala and the Bandah Formations are assigned to Lower Eocene (Ypresian) and Middle Eocene (Lutetian) respectively on the basis of microfauna contained in them.
Foraminiferal Biostratigraphy and Geological Evolution of the Thanjavur Sub-Basin, South India
Authors: Banerji Ranjit K. 
Published: November 2024

Abstract
The foraminiferal biostratigraphy of the marine Meso-Cenozoic sequence of Thanjavur sub-basin, situated in the south-western part of the Cauvery basin, is worked out in detail. On the basis of the distribution of well known planktonic and associated benthonic foraminifera, fifteen biostratigraphic zones ranging in age from Albian to Lutetian, are recognised. It is suggested that the Cretaceous-Tertiary boundary should be placed between Globotruncana gansseri - G. contusa assemblage Zone and Globorotalia velascoensis Zone in this sub-basin. The foraminiferal fauna of these zones are compared with those of the exposed marine sequence in the northern parts of the Cauvery basin. Certain aspects of inter-regional stratigraphic correlation and palaeoecology are discussed.