bluuebunny/crossref_metadata_2025_split huggingface dataset:
Stratigraphy of the Upper Precambrian Albaka Belt, East of the Godavari River in Andhra Pradesh and Madhya Pradesh
Authors: Srinivasa Rao K. , Sreenivasa Rao T. , Rajagopalan Nair S. 
Published: November 2024

Abstract
The lithostratigraphic succession worked out for the Upper Precambrian of Venkatapuram-Cherla area includes Cherla Formation, Somandevara Quartzite, Tippapuram Shale Utlapalli Conglomerate, Albaka Sandstone, Nambi Breccia and Doli and Usur Sandstones. Three disconformities, one each at the base of the Somandevara Quartzite, Utlapalli Conglomerate and the Nambi Breccia, have been inferred. Of these, the one at the base of the Nambi is believed to be the most significant one. Based on gross lithological similarity and relative stratigraphic position, the different Upper Precambrian units of this area are correlated with those of the already established Pakhal and Sullavai Groups of the main Upper Precambrian belt, west of the Godavari River. The correlation implies that the nature of the contact between the Pakhal and Sullavai Groups of the, main Upper Precambrian belt on the western side of the Godavari, a much debated question, is a profound unconformity.
The Ophiolitic Suture Zones of the Ladakh and the Kallas Region-A Comparison
Authors: Gansser A. 
Published: November 2024

Abstract
The 2500 km long Himalayan Suture Zone is discussed along two important crosssections, the Ladakh and the Kailas region. The ophiolitic rocksand the structural setting is in both areas surprisingly similar. In the north the Transhimalayan plutons are transgressed by the Kailas molasse on which elements of the Suture Zone such as flysch and ophiolitic melanges are thrust towards the north. Contrasting to this movement, ophiolitic nappes are thrust southwards on top of platform sediments such as the Spongtang nappe in the Ladakh region and the Kiogar-Jungbwa nappe south of Mount Kailas. In both nappes, conspicuous uItrafemic rocks form the highest thrust elements. Southward thrusting preceded the compressional northwards thrusting.
Calcite Fabric in Relation to the Tectonic Setting of the Precambrian Rocks Around Karera, District Bhilwara, Rajasthan, India
Authors: Sharma Ram S. 
Published: November 2024

Abstract
Subfabric studies of calcite from an Aravalli marble have been carried out by measuring [0001], e-lamellae, r-cleavages, and a-axes in each grain in the rock-slide. The coaxes maximum is located nearly normal to the regional foliation (S2-surface), thus conforming to the results of the experimental deformation of calcite. The orientation of [0001] is attributed to the syntectonic recrystallization accompanying the first deformation D1; while the (0112) orientation appears to be related to the late phase of D1 or possibly to the second deformation, D2, which refolded the Aravalli rocks and the underlying Banded Gneissic Complex. The two deformation phases have been established on the basis of different structural elements in the rocks of the investigated area.
Chemistry and Mineralogy of &lt; 2μm Size Fraction of Non-Marine Cyclothems, Dunkard Group, Upper Pennsylvanian-Lower Permian, in Ohio, U.S.A
Authors: Ramesam V. 
Published: November 2024

Abstract
The acid insoluble &lt; 2μm size fraction of 22 sandstones, 36 shales and 15 limestones from the largest exposed section of the Dunkard sediments was analysed by X-ray diffraction for the clay minerals and by spectrographic methods for trace elements. After verification of the precision and accuracy in the data, the results were statistically processed.
Vermiculite, kaolinite, illite, chlorite and mixed layer lattice minerals are the principal clay minerals identified. Montmorillonite was identified only in two samples out of 75 and corrensite in a single sample. The clay mineralogy appears to have been diagenetically altered particularly in sandstones. The migration and incorporation of trace elements into the clay minerals differ with the lithological type being deposited irrespective of the clay mineralogy. Ni and Cr seem to be present in vermiculite. Fe in the &lt; 2 μm fraction of sandstones seems to have been dispersed by more than one process. The K/Rb, Ga/Ti ratios have distinct ranges for each of the lithologies.
Compared with crustal abundance values (Taylor, 1964), the average Dunkard rock has higher K, Rb, Mn, Ga, Y, Ni, Sc and Cr, and lower Ti, Fe, V, Zr, Cu, Co and Sr values.
Polyphase Folding Deformation in the Hutti-Maski Schist Belt, Karnataka
Authors: Roy Abhinaba 
Published: November 2024

Abstract
Three phases of folding deformation (F1, F2 & F3) are recognised in the Hutti-Maski schist belt. The first two phases (F1 and F2) are quite pronounced producing regional folds whereas the last one (F3) is of mild intensity. F1 folding is accompanied by the development of schistosity (S1) in metabasalt and metasedimentaries, mylonite banding (Sd) in gold quartz veins and minor folds on bedding plane (So) and vein quartz. Two major F1 folds, viz., a syncline and an anticline could be traced in the area on the basis of orientation of pillow structure in metabasalt. Gold mineralisation in Hutti-Maski schist belt is mainly controlled by first phase of folding (F1) and associated regional metamorphism. F2 fold shows clear evidence of superposition on F1. F1 axial trace is folded by F2 folds. F2 folding is accompanied by the development of crenulation or slip cleavage (S2), minor folds on S1 and Sd and shear fractures and faults. F2 fold is represented by two major folds, viz., an antiform and a synform having axial traces along NNW-SSE to NW-SE direction and plunge around 45° to 50° towards Nw to NNW. A time gap between F1 and F2 is marked by the intrusion of a granodiorite body. F3 is developed on the limbs of F2 folds, and is accompanied by the development of S3 cleavage and kink band or chevron folds. Axial plane of F3 fold trends N75°E-S75°W (approx.) with vertical dip. Fold axis (F3) shows very steep westerly plunge.
Copper Mineralization in Padar-ki-Pal, Dungarpur District, Rajasthan
Authors: Degaonkar Satish , Panchapakesan V. C. , Sahu K. C. 
Published: November 2024

Abstract
Copper mineralization in Padar-ki-pal is localised along a N25°E striking phyllite-quartzite contact, transected by three sets of steeply dipping joint planes. Mineralization is in the form of veins, disseminations and permeations of chalcopyrite and other related sulphides. Textures and other related structures reveal the replacement nature of the deposit. Fluid inclusions indicate an aqueous transport of ore elements by a brine undersaturated with respect to highly soluble salts which boiled off at least at the end stage of mineralization. The filling temperature of the inclusions showed signs of entrapment of a homogeneous liquid solution, ranging from 200° to 270°C.
Freshwater Xenacanthid (=Pleuracanth) Shark Fossils from the Upper Triassic Maleri Formation, India
Authors: Jain S. L. 
Published: November 2024

Abstract
Xenacanth (=pleuracanth) shark fossils are exclusively known from the freshwater deposits from late Devonian up to the Upper Triassic. Triassic occurrences are sporadic and have so far not been supported by skull material. Teeth and skull material from the Upper Triassic Maleri Formation consists of well preserved characteristic' Diplodus' type teeth and a few calcified cartilages of the skull region. It shows affinity with the Australian X. parvidens from the Lower Wianamatta Series of New South Wales and X. moorei from the Keuper of Somersetshire (England) and Wurtemberg (Germany). Being the first record from India, the material is assigned to X. indicus sp. nov. The three species viz., X. parvidens, X. moorei and X. indicus represent the last survivors of the family Xenacanthidae in the Upper Triassic.
Application of Aerial Photographs and Landsat Imagery for Geological Mapping Around Chandrapur (Maharashtra)
Authors: Subbarao B. V. , Alasingrachar M. A. , Shah S. D. 
Published: November 2024

Abstract
Linear quartzite ridges were established in the NE part of the imagery, from the aerial photointerpretation and later ground check. The extreme eastern part of the imagery has distinct evidences of faulting within the folded strata. Other structural features such as fault planes and doubly plunging synclinal features are also established. Three major formations such as granites, quartzites, and granite gneisses and schists could be delineated on the photogeological map along with the dolerite dykes of later origin. Numerous water bodies with N-S and NNW-SSE alignment are suggestive of the presence of hidden basement faults. Also the Wainganga river's older courses could be clearly marked, besides establishing the structurally controlled flow of Penganga, Wardha and Wainganga rivers. Dissimilar rock units are differentiated from the interpretation of colour composites.
Discovery of Late Palaeozoic Brachiopod in the Upper Krol of the Nainital Hills, Kumaun Himalaya
Authors: Valdiya K. S. 
Published: November 2024

Abstract
Discovery of Linoproductus sp. in the upper part of the Upper Krol Limestone near Nainital indicates Upper Palaeozoic, probably late Carboniferous or Early Permian age not only of the lithostratigraphic unit, but also of the assemblage of stromatolites having distinctive morphology and restricted vertical distribution.
Lamprophyres from Indian Gondwanas - K-Ar Ages and Chemistry
Authors: Sarkar Amitabha , Paul D. K. , Balasubrahmanyan M. N. , Sengupta N. R. 
Published: November 2024

Abstract
Lamprophyric dyke rocks occurring in the Indian Gondwanas (Permian-Lower Cretaceous) form a consanguinous suite ranging from ultrabasic mica-peridotite to micro-syenitic assemblages. Chemical characters include low SiO2 (ca. 40% or less), high (FeO+MgO) and high MgO/FeO and K2O/Na2O ratios. The petrographic and chemical characters have been discussed in a broad framework after Rock (1977). K-Ar radiometric ages on four biotite separates and one whole rock from three different localities range from 105 to 121 Ma and are believed to represent true crystallisation ages.
On the Phase Transformation of Bauxite Phutkapahar Bauxite Deposit, Madhya Pradesh, India
Authors: Ghosh K. P. 
Published: November 2024

Abstract
Optical, X-ray, D.T.A. and Scanning Electron Microscopic studies on the gibbsitic bauxite samples of Phutkapahar bauxite deposits, Madhya Pradesh are presented. Natural gibbsite changes to boehmite -----? ? A1203 --- --? a A1203 in response to variable thermal kinetics. The transformation is topotactic, diffusion controlled and is largely defined by both homogeneous and inhomogeneous mechanisms of dehydration.
Electron Microscopic Studies of Clay Minerals from Three Bauxite Profiles
Authors: Balasubramaniam K. S. , Paropkari A. L. , Nagarajan R. 
Published: November 2024

Abstract
Laboratory studies of three bauxitic profiles from Maharashtra and Tamil Nadu suggest that plagioclase feldspar alters to gibbsite via halloysite and not from kaolinite. The alteration characteristics of feldspars and the morphological aspects of clays leading to the genesis of bauxites were studied under electron microscope.
Petrological Study of Ghuneri Lignito-Bituminous Coal, District Kutch, Gujarat, Western India
Authors: Pareek H. S. 
Published: November 2024

Abstract
The Umia Beds (Wealden) exposing a seam of Iignito-bituminous coal 75 cm in thickness near Ghuneri in Kutch, is of Cretaceous age. The coal is high in moisture (8.09-12.15%), ash (11.61-23.81 %), and sulphur (1.91-3.04%) contents, and is lustrous, banded and vitrain-rich. It is composed dominantly of collinite, and commonly of telinite, showing microstructural details of the secondary wood palmoxylon (?) flora. Fusinite is common and shows cell lumen occupied by carbonized resins or a dark coaly matter possibly bituminite. Fusinized resins occur as traces and are similar to those in the Gondwana coals. Fungal sclerotia is recorded and is similar to that in the Tertiary lignites.
The coal is distinct and different from the Gondwana coals or Tertiary lignites, but shows greater resemblance in petrological characters to the Permian coals of Damodar Valley.
Stratigraphy and Structure of the Precambrian Banded Iron Formation and Chromite-Bearing Ultramafic Rocks of Sukinda Valley, Orissa
Authors: Chakraborty K. L. , Chakraborty T. L. , Majumder Tapan 
Published: November 2024

Abstract
The Sukinda Valley of Orissa is underlain by the banded iron formation (BlF) and chromite-bearing ultramafic rocks of Precambrian age. Besides these, local exposure of a quartz-arenite bed with basal conglomerate is correlated with the Kolhans. A basal quartzite horizon is conformably overlain by the BIF. lhe quartz-arenite (Kolhans?) with a conglomerate at the base lies with a local disconformity over the BIF. Chromitebearing ultramafites are pre-kinematic intrusives into the iron formation and have been co-folded with the older sediments. Orthopyroxenite and granitic rocks are intrusive into the chromiferous ultramafites. Occasional intrusive dolerite dykes in the valley may be correlated with the Newer Dolerites of Singhbhum.
The regional structure of the Precambrian rocks of the Sukinda Valley, as established by the present authors, is a cross-folded doubly plunging syncline with the culminated fold axis striking ENE-WSW which is parallel to the main fold axis of the Eastern Ghats Orogenic belt. The plunge of the main fold axis is towards NE and wsw. The cross-folded axis, lying between Tungaisuni and Champajhar villages, trends NNW-SSE and is subparallel to the cross-folded axes of the Eastern Ghat Orogenic belt.
Gondwana Type of formation with Phosphatic Rocks in S.E. Nepal
Authors: Bashyal R. P. 
Published: November 2024

Abstract
A new Formation called the Barahakshetra Formation is recognised in Southeastern Nepal. It is separated from the Siwaliks (Tertiary) to the south by the MBT and has a tectonic contact with the Sanguri Formation (Lower Palaeozoic ?) and the Metamorphic Series (Precambrian ?) to the north.
The basal part of the Formation is marine with radiolaria, glauconite and with a penecontemporaneous trachyte-keratophyre volcanism. A glacio-marine episode is represented by the pebbly shales in the eastern part of the basin. The continental character and the regressive nature of the upper part of the Formation is indicated by the detrital materials with coal and plant fossils. The sediments were deposited in a epicontinental basin of paralic type. Littoral zones (intertidal-supratidal) are indicated by many sedimentary features.
The volcanic sandstones and the conglomerates of the region are feebly phosphatic. The Barahakshetra Formation is compared with corresponding units of the Gondwana Formations of the Himalaya. It is noticed that lithostratigraphically the Barahakshetra Formation is similar to that of Darjeeling-Sikkim area. The Gondwana affinity is confirmed by the presence of plant fossils. The geological significance of this Formation is discussed.
Middle Eocene Benthonic Foraminifera from the Vinjhan-Miani Area, Kutch-Palaeoecological Significance
Authors: Jauhari A. K. 
Published: November 2024

Abstract
An attempt has been made to discuss the palaeoecologic significance of the foraminiferal assemblage recorded from the Middle Eocene rocks exposed around the villages Vinjhan and Miani. The interpretation leads to the conclusion that the Middle Eocene rocks were deposited in inner-to mid-neritic environment characterized by warm water conditions.
Redlichid Fauna from the Cambrian of Kashmir
Authors: Shah S. K. , Raina B. K. , Razdan M. L. 
Published: November 2024

Abstract
The redlichid fauna from the Lower Cambrian of northwestern Kashmir is described. In addition to Redlichia noetlingi (Redlich), it includes R. cf. knjazevi Repina and Tungllsella obesa Repina, not recorded from India so far. Inarticulate brachiopods, Botsfordia granulata (Redlich) and? Neobolus are also described from the same zone. The fauna corresponds to Botomian and represents upper middle part of Lower Cambrian.
Geology and Geochemistry of Paragneisses from the Javanahalli Schist Belt, Karnataka, India
Authors: Naqvi S. M. , Narayana B. L. , Rama Rao P. , Ahmad S. M. , Uday Raj B. 
Published: November 2024

Abstract
The lowermost member of the Javanahalli schist belt consists of meta-arkoses/ paragneisses with interbedded epidote-quartzite and calc-silicate bands. These meta-arkoses exhibit relict current-bedding, arkosic texture and grain-to-grain variation in anorthite content within the same sample. Plagioclase is subordinate to K-feldspar and is relatively more weathered and sericitized. Orthoclase predominates over microcline in the total K-feldspar content and the quartz/feldspar ratio is generally very low. The meta-arkoses appear to be first-cycle sediments.
The composition of these paragneisses is unusual for Archaean metasediments. They are enriched in K, Si, Fe, Mg, Th, Rb, Ni, Cr and Co and depleted in Na, AI, Sr and often in Ca. The meta-arkoses of Javanahalli schist belt may be the product of strong and/or rapid chemical disintegration of Archaean tonalitic gneisses and basic and ultrabasic rocks. all of which were prominent components of the continental crust at the time the Javanahalli belt formed. If the meta-arkoses have not undergone major metasomatism, then their high abundance of K and Rb may indicate intense chemical leaching of these tonalitic source areas. Most of the saIt of the primitive oceans might have been derived from this intense leaching of the ancient cratonic tonalite gneisses.
A Tectono-Stratigraphic Model of the Chitradurga Schist Belt, Karnataka, India
Authors: Mukhopadhyay Dhruba , Baral Mohan Chand , Ghosh Debashish 
Published: November 2024

Abstract
The regional structure within the Chitradurga schist belt consists of a central antiform flanked by two synclines on either side. The central antiform is a second generation struc:ture which has refolded an earlier syncline whose axial trace is now exposed on either side of the central antiform. The second generation antiform shows regional plunge culminations and depressions along its axis. The earlier syncline had originally curved fold axis and was a canoe shaped fold. In the southern part of the schist belt a tectonic slide has cut off the lower limb of the early syncline. This came into existence before the second phase of folding. The stratigraphic sequence within the schist belt has been worked out taking into account this structural framework.
Heavy Minerals in the Sediments on the Outer Continental Shelf between Vengurla and Mangalore on the West Coast of India
Authors: Kidwai R. M. , Nair R. R. , Hashimi N. H. 
Published: November 2024

Abstract
Fifty-eight sediment samples from the outer continental shelf between Vengurla and Mangalore were analysed for heavy mineral content. The heavy minerals consist of principally opaques, hornblende, epidote, garnet, sillimanite, hypersthene and zircon, with minor amounts of andalusite, augite, kyanite, monazite, muscovite and tremolite-actinolite. This mineral assemblage and the distribution pattern define four heavy mineral provinces on the continental shelf from Vengurla to Mangalore. Further, the mineral assemblage suggests derivation from mixed metamorphic and igneous terrain with a predominant contribution from metamorphic rocks.
The Structural Set up of Apart of the Malangtoli Iron Ore Deposit, Orissa
Authors: Chatterjee A. K. , Mukherji P. 
Published: November 2024

Abstract
The paper describes the localisation of iron ore bodies in the Malangtoli group forming the southeastern end of the Bonai Synclinorium comprising Singhbhum-Keonjhar-Sundergarh group of iron formations. Three fold systems affect the area. Barring a few instances which are due to facies changes, the overall pattern of Occurrence of iron ore bodies is fairly conformable with the tectonic set up and the behaviour of such ore bodies are continuous with the structural pattern. The distribution of iron ore body/bodies in space is/are controlled by the superposed fold systems, the ore body reaching maximum depths in structural basins and/or canoes and minimum depths (occasionally base rock outcropping) in structural highs, i.e., domes and inverted canoes. Certain conclusions arising out of this are analysed.
Polyphase Deformation of Ajabgarh Stage Rocks, Delhi Group, Around Narnaul, Mohindergarh District, Haryana, India
Authors: Bhola Anand Mohan , Varadarajan S. 
Published: November 2024

Abstract
A detailed study and analysis of all the planar and linear elements in the lithic units of the area, in both meso and macro scale reveal that they bear the impress of three phases of folding, F1 F2 and F3. The most dominant phase is the second phase resulting in open asymmetric folding with high wave length/amplitude which express in mesoscale crenulations on the planar surface of F1 folding. The F1 phase is responsible for the regional foliation S1 which is parallel to lithic banding S0. The tight isoclinal folds develop appressed surface which act as form-surface of F2. The F1 and F2 are generally co-axial. The last phase of folding F3appear as broad open cross-folds broadly warping the pre-existing foliation. This phase can distinctly be observed on map scale.
Distinction between each phase and the associated structures is based on the overprinting relations, in particular the bending of axial surface foliation and other interference patterns between the existing phases. Structural analysis of the area indicates operation of a predominantly sub-horizontal NW-SE oriented stress.
Grain Size Variation in the Sediments off Tuticorin Harbour, Tamil Nadu
Authors: Venkatesh K. V. , Ray I. 
Published: November 2024

Abstract
The size parameters of the near shore sediments off Tuticorin vary as follows: inclusive graphic mean from 1.41 to 2.22 phi; standard deviation 0.58 to 0.91 phi; skewness - .07 to - .37 and kurtosis 0.91 to 1.15. Decrease in the values of mean size towards southwest indicates the movement of sand in that direction which is largely aided by the wind induced currents. A close correlation between mean grain size and sorting is mferred. Sporadic occurrences of coarser sand nestled by finer ones noticed closer to the site of break-waters speaks of the low transporting ability of the back wash. The important mode of transport is through saltation and traction.
Manganese Silicate-Carbonate Protore (Queluzite) from the Srikakulam Manganese Belt, Andhra Pradesh
Authors: Krishna Rao S. V. G. , Bhattacharyya Samit , Sarma K. J. 
Published: November 2024

Abstract
Manganese silicate-carbonate protore (queluzite) and a rare manganese olivine (knebelite) are being reported for the first time from India. The protore is comparable to the 'Queluzite Type' and occurs as conformable bands in close association with manganese ore body as well as different members of the Khondalite Group of rocks. So far, the knebelite is reported to occur in association with other manganese minerals, particularly in iron-manganese ore deposits and their associated skarns. It is surmised that the protore represents metamorphic equivalent of carbonate-silica-bearing manganiferous sediments.