bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quaternary Geology and Geomorphology of a Part of Ghaghara-Rapti-Gandak Sub-Basins of Indogangetic Plain, Uttar Pradesh
Authors: Dwivedi G. N. , Sharma S. K. , Prasad Surendra , Rai R. P. 
Published: November 2024

Abstract
The Quaternary sediments of the Indogangetic plain in eastern part of Uttar Pradesh, can broadly be subdivided into two groups lithostratigraphically, viz. the Older Alluvium and the Newer Alluvium. The former is subdivided into basal Banda Older Alluvium (BOA) comprising of variegated clays and clastic sediments of Chitrakoot Formation encountered in the boreholes in the southern part and its equivalent Upper Siwalik in the northern part and an upper Varanasi Older Alluvium (VOA) and Palaeo Bhur deposits. The Newer Alluvium includes Bhat Alluvium, GhagharalRapti/GandakiChhoti GandaklChhoti Sarju Terrace Alluvium and their Recent Alluvia. The lithounits correspond to two broad geomorphic units, viz. an upland - the Bhangar surface and a low lying area demarcating the flood plains - the Khadar surface. The former consists of a piedmont zone of alluvial fans and an alluvial plain. while the later consists of terraced valley. The evolutionary history of Quaternary sedimentation commenced with a change in the configuration of Middle Siwalik basin converting it into much wider one by transgressing southward further over Bundelkhand gneissic complex and Vindhyan basement probably, during Upper PliocenelLower Pleistocene with sediment supply in the southern part from the Peninsular provenance constituting the Banda Older Alluvium and with sediments derived from Himalaya in northern part of the basin to constitute the Upper Siwalik. This was followed by a break in sedimentation caused due to upliftment during Middle Pleistocene resulting in a new basin formation superimposed over previous one, with sediment influx from the north, to the deposition of Varanasi Older Alluvium. The Upper Pleistocene glaciation brought an end to this sedimentation phase. The gradual warming up and retreat of glaciers accompanied with a large amount of sediment supply led to the formation of Bhat Alluvium in piedmont zone. A number of fluvial regimes, namely Ghaghara, Rapti, Gandak etc. carved out their new, narrow basins with warming up and increased precipitation during Holocene represented by their terraces. The ongoing phase of sedimentation is restricted to within the present active flood plain in response to reduced discharge and sediment supply.
Review of Precambrian Porphyry Cu ± Mo ± Au Deposits With Special Reference to Malanjkhand Porphyry Copper Deposit, Madhya Pradesh, India
Authors: Sikka Deshbandhu , Nehru C. E. 
Published: November 2024

Abstract
Precambrian porphyry type Cu±Mo±Au deposits are present in many parts of the world including Australia, Brazil, Canada, China, Finland, India, Namibia, Russia, Sweden, and Zambia. Most of them are associated with calc-alkaline or alkaline subduction zone volcanics or granitoids of the I-type. Precambrian deposits range in age from 33l4±6 Ma to 561±9 Ma. The majority of the deposits fall into four age groupings with peaks around 3300±100Ma, 2700±100Ma, 1900±100 Ma. and 1100 ± 100 Ma which are indicative of major tectonic and magmatic episodes in different parts of the world. Precambrian deposits have many similarities with the younger porphyry copper deposits in the Phanerozoic. Some outstanding examples include Malanjkhand deposit (789 Mt x 0.83% Cu; 0.004% Mo: 0.2 gm/T Au; 6 gm/T Ag) and Tongkuangyu, China (380 Mt x 0.67% Cu) are in production. The Troilus Lake deposit, Quebec, Canada (42.9 Mt x 0.12% Cu; 1.4 gm/t Au; 1.4 gm/ t Ag) and Haib River, Namibia (600 Mt x 0.3% Cu) are being considered for exploitation.
After a review of the salient features of porphyry Cu±Mo±Au deposits in general and those of the Precambrian porphyry Cu±Mo±Au age in particular, it is suggested that Precambrian terrains should be good targets for exploration.
Lithostratigraphy and Hydrocarbon Prospects of the Olpad Formation of Paleocene-Early Eocene Age in Ahmedabad-Mehsana Tectonic Block, Cambay Basin
Authors: Samanta M. K. , Gavarshetty C. P. , Kumar Ashish 
Published: November 2024

Abstract
The Olpad Formation of Paleocene-Early Eocene age represents the oldest Tertiary clastic deposits. in the Mehsana area, North Cambay Basin. This unit is characterised by its heterogeneous lithologic association of volcanic conglomerate, volcanic wacke, trapwash, siltstone and shale, deposited by alluvial fan systems along fringes of palaeohighs and lacustrine to brakish water condition in the existing palaeolows. Recent exploratory drilling proved the occurrence of hydrocarbons in this formation. This significant find has prompted the necessity of identifying potential hydrocarbon reservoirs. The formation has been subdivided into three lithostratigraphic units (Unit I - III in descending order) based on sedimentary facies and well log characteristics. The reservoir characteristics of the sediments of Olpad Formation has been worked out based on sedimentological, SEM and XRD studies.
Lithostratigraphic correlation, structural configuration and thickness variation have been discussed. The study reveals that the distribution of different lithostratigraphic unit is controlled by tectono-sedimentation factors and the volcanic wacke lithofacies of Unit-I and III constitute the reservoir rock in the Olpad Fonnation. The study led to the identification of Umiwa. Khambel and Gamanpura as prospective areas for future exploration for structural-cum-stratigraphic traps.
Aseismicity of the Andaman Subduction Zone and Recent Volcanism
Authors: Dasgupta Sujit , Mukhopadhyay Manoj 
Published: November 2024

Abstract
The Barren Island volcano in central Andaman Sea erupted afresh on March 29, 1991, since its last eruptions in 1789 and 1832. Tectonic framework of the Barren Island volcano is delineated by a set of seismically mapped faults, including the West Andaman Fault, which. connects to the Semangko Fault in Sumatra. The morphology of Andaman Benioff zone as seen on a vertical section reveals a seismic gap at 90-110 km depth. Spatially it relates to the zone of current volcanism of the Barren and its neighbouring Alcock Seamount in a structurally depressed area. The seismic gap in the Benioff zone is interpreted as a zone of partial melting in the descending Indian Ocean lithosphere which prevents stress accumulation owing to the decreased viscosity. Best double couple solutions for the Barren Island earthquakes of October 10 and December 25, 1990, which preceded the volcanism suggest that rupturing through normal dip-slip faulting prevailed in the overriding Burma plate prior to the recent volcanism. Pronounced back-arc seismicity at shallower depths is seen further to the east and southeast of the Alcock Seamount; this relates to back-arc rifting under the Andaman Sea.
Carbon Isotope Thermometry in Marbles of Ambasamudram, Kerala Khondalite Belt, Southern India
Authors: Satish Kumar M. , Santosh M. , Wada H. 
Published: November 2024

Abstract
Calcite-graphite isotope exchange thermometer is a useful tool in elucidating the peak metamorphic temperatures in regionally metamorphosed marbles, for which normal cation exchange thermometers are not available.
Geothermometric and Oxygen Fugacity Studies of Mayurbhanj Basic Igneous Complex
Authors: Das S. K. , Mukherji S. 
Published: November 2024

Abstract
The basic igneous complex of Mayurbhanj is a differentiated suite composed of harzburgite, gabbronorite, leucogabbronorite and anorthosite. EPMA of the coexisting oxides in the rock samples reveal that magnetite-ilmenite have re-equilibrated between 770°C and less than 500°C and fo2, of 10-16 to less than 10-25. Ilmenite granules and thick lamellae have identical composition and approach pure FeTiO3. The chrominn spinel-olivine geothermometry in harzburgite suggests a temperature of 1263°C. The pyroxene geothermometric data in gabbroic rocks indicate equilibration temperature range of 819° C to 1071° C. The thermometric data indicate that the magnetite and ilmenite equilibrated at lower temperature than the coexisting pyroxenes for a particular rock sample.
Isotopic Signature of Pan-African Rejuvenation in the Kerala Khondalite Belt, Southern India: Implications for East Gondwana Reassembly
Authors: Unnikrishnan-Warrier C. 
Published: November 2024

Abstract
Sm-Nd isotope systematics on mineral separates from sillimanite-and cordierite-bearing metapelite (khondalite), and garnet-and biotite-bearing gneiss (leptynite) from the Kerala Khondalite Belt (KKB), southern India, yielded mineral isochron ages (wr-feld-bio-gar) of 537 ± 27 Ma (MSWD = 0.9) and 534 ± 26 Ma (MSWD = 1.23) respectively. Rb-Sr systematics in the same samples gave wr-feld-bio mineral isochron ages of 437 ± 9 Ma (MSWD = 0.67) and 467 ± 9 Ma (MSWD = 0.76), These results provide the first mineral isochron ages for the regional metasedimentaries in the KKB. The e (Nd T) values at 550 Ma for Khondalite and leptynite are -22.7 and -21.8 respectively. These results demonstrate a complete rejuvenation of the crust during Pan-African times. Coeval alkaline plutons emplaced along fault-lineaments in this area suggest an extensional tectonic regime. Geochronologic correlations with the Lutzow-Holm Bay Complexes in East Antarctica, and the Highland and Southwestern Complex of Sri Lanka show that a similar Pan-African tectonothermal event manifested in all the East Gondwana crustal fragments.
Fossil Wood in Tertiary Cuddalore Sandstones near Tiruvakkarai, South Arcot District, Tamil Nadu
Authors: Subramanian K. S. , Renganathan M. , Kanishkan B. 
Published: November 2024

Abstract
In the CuddaIore sandstones of Mio-Pliocene age in the east coast of Tamil Nadu, the lignite horizon in Neyve1i is succeeded by pebbly sandstones with petrified tree trunks in Tiruvakkarai. Obviously, fluctuations in climate during Mio-Pliocene gave rise to different environments of deposition of sediments and vegetal matter, resulting in the carbonisation of vegetal matter in Neyveli and siliceous petrification of tree trunks in Tiruvakkarai.
Textural Parameters, Discriminant Analysis and Depositional Environments of the Tcri sands, Southern Tamil Nadu
Authors: Joseph Sabu , Thrivikramaji K. P. , Anirudhan S. 
Published: November 2024

Abstract
Results of analysis of size data by frequency curves and multi-group discriminat analysis (MGDA) indicate that inland Teri Deposits (ITDs) are very much similar to colluvium, formed by mass-wasting and fluvial processes, whereas Coastal Teri Deposits (CTDs) Very likely originated in mixed environments i.e., beach and dune. further, it is proposed that the ancestral sediments of present day CTDs would have originated from the vast reservoir of shelf sand that remained subaerially exposed during the low sea leval stands which coincided with Late Pleistocene glaciation.
Basin Evolution Study of the Machundri River, Southern Saurashtra Coast, Gujarat
Authors: Rakshit Prabal , Sinha A. K. 
Published: November 2024

Abstract
The Neogene/Quaternary boundary is reported to be erosional. The Pleistocene miliolite limestone shows the development of a sequence of palaeo-beach-dune complexes with the gradual fall of sea level. The late Pleistocene-Holocene stratigraphic units comprise different generations of deltaic sediments aggrading older tidal marshes and backswarnps. The late Holocene sea-level fall helped in delta progradation and the development of different accretionary units all along the coast.
Occurrence of Rare Earth Elements in Panchpatmali Bauxite Deposit and Red Mud, Koraput District, Orissa
Authors: Subrahmanyam A. V. , Singh Jagmer 
Published: November 2024

Abstract
The geochemistry reveals LREE enrichment, high degree of fractionation, positive Ce anomalies and negative Eu anomalies in the samples. Red mud contains 18 to 29% of heavy minerals; and thus the red mud could be an alternative source to beach sands.
Petrology and Geochemistry of the Granitoids of Central Gneissic Complex in the Kameng district, Arunachal Pradesh
Authors: Dikshitulu G. R. , Dhana Raju R. 
Published: November 2024

Abstract
Petrology and geochemistry (major, minor and trace elements including REE) of the different granitoids from Central Gnessic Complex indicate that, (a) the dominant Palaeoproterozoic migmatite, hornblende granite gneiss, two-mica granite and augen gneiss are syn-kinematic, autochthonous, peraluminous, low-Ca granodiorite, with the first three being of S-type formed by highdegree (&gt;50%) anatexis of sediments of psammopelitic composition, whereas the augen gneiss is I-type formed by partial melting of a basic rock of mantle affinity coupled with notable crustal contamination and affected by soda metasomatism; (b) the minor Mesoproterozoic Salari granite is late-kinematic, allochthonous, metaaluminous, epidote-bearing, high-Ca monzogranite of I-type formed by partial melting of basic rock from crustal depth; (c) the youngest (ca. 30 Ma) tourmaline granite is post-kinematic, allochthonous, strongly peraluminous, high-level syenogranite of S-type, with its parental melt derived from a peraluminous granitoid by anatexis induced by large volume of volatiles and fluids, and (d) tectonically, these granitoids are of 'syn-collision' type.
Recognition of Paleo Pennar Delta: Assessment of Aquifer Parameters and Environmental Constraints
Authors: Radhakrishna I. 
Published: November 2024

Abstract
A fan-shaped paleodelta existed during Quaternary period with buildup of paleochannels along major lil1eament~. This paleodelta region is characterised by thick fluviatile granular sediments, low electrical conductivity and chloride levels. Ground water flow paths, subsurface aquifer geometry and transmissivity trends for paleo Pennar delta region are presented and discussed.
Structural Appraisal of Parts of Archaeans, Satpuras and Chhattisgarh Basins Around Mandala - Raipur Districts, M.P., India, Using Total Magnetic Field Data
Authors: Singh V. P. , Singh O. P. , Singh C. L. 
Published: November 2024

Abstract
Detailed ground magnetic surveys over parts of Archaeans. Satpuras and Chhattisgarh basins belonging to different ages around Mandala-Raipur has been carried out. Detailed investigations provide depth of magnetic sources, basement structural trend. nature of intrusive bodies and thickness of sediments in the basins. The basement structural trend along the five profiles in Archaeans (AA'and BB'), Satpuras (CC') and Chhattisgarh (DD' and EE') have been derived which ranges from 1.5 to 3.5 km. The Archaean and Chattisgarh basins show two dyke like features at depth of 0.28 and 1.26 km. It also reflects upwarping of the basement along the profiles.
A Record of Algal Oncolites of Lower Permian Age in Cauvery Basin, Tamil Nadu, India
Authors: Yadagiri K. , Govindan A. 
Published: November 2024

Abstract
A conventional core abstracted above the basement in an exploratory well PUNDI-A in the western part of Tanjore sub-basin, indicated the presence of algal oncolites of Lower Permian age inferred from palynofloral assemblage in the under/overlying Shales.
A Laboratory Study of the Flocculation of Dissolved Heavy Metals in Kali RiverDuring Estuarine Mixing, West Coast of India
Authors: Balakrishna K. , Manjunatha B. R. , Shankar R. 
Published: November 2024

Abstract
River water-sea water mixing experiments were carried out to study the time dependence of flocculation process, the flocculation behaviour of dissolved Cu, Pb, Zn, Ni, Co, Mn, Cr and Fe in the Kali estuary. Flocculation appears to be maximum at high salinities (&gt;25‰) and is rapid, about 7 to 60% of the dissolved metal content flocculating within half an hour of mixing. This brings out the role of sea water as a powerful flocculating agent for the dissolved load of river water.
Elemental Chemistry of Ilmenite - An Indicator of Provenance?
Authors: Bhattacharyya Samit , Sengupta Ranadhir , Chakraborty Manas 
Published: November 2024

Abstract
Elemental chemistry of ilmenite has been determined with a view to studying the applicability of the parameter in determination of provenance of the placer minerals. While the values of Mn/Mg ratio conform to the already determined provenance of the east coast occurrence, the west coast ilmenites have lower values for this ratio suggesting a basic rock dominated provenance rather than chamockite/khondalite/migmatitic source. Present study recommends a fresh look at provenance study of the west coast placers vis-a-vis examination of applicability of Mn/Mg values of ilmenite in relation to the provenance.
Stratigraphy and Tectonic Setting of the Trans-Aravalli Neoproterozoic Volcanosedimentary Sequences in Rajasthan
Authors: Chore S. A. , Mohanty M. 
Published: November 2024

Abstract
At least three formations in Punagarh Group and two in Sindreth Group are identifiable on the basis of varied lithoassemblages. The geochemical parametres of the mafic (mainly pillowed) and felsic volcanics suggest that their effusion is linked to the deep seated fractures responsible for the formation of intracratonic grabens. The association of bimodal volcanics and coarse clastics in linear grabens suggest the development of retroarc basins as a consequence of subduction of South Delhi Oceanic-transitional crust under the western Marwar continental crust. The Trans-Aravalli region in Rajasthan contains Neoproterozoic sequences of Punagarh and Sindreth groups occurring in isolated linear basins.
Conditions of Metamorphism of the Garnet-Cordierite Gneisses from Malai Mahadeswara Hills, South India and the Origin of Zn-Cr-Rich Spinel
Authors: Fonarev V. I. , Janardhan A. S. , Konilov A. N. 
Published: November 2024

Abstract
A spinel phase with unusually high ZnO (8.8-11.0) and Cr2O3 (13.2-15.8%) contents is found in garnet-cordierite-sillimanite bearing migmatised pelitic bands interbedded with tonalitic charnockites of Malai Mahadeswara (MM) Hills. The textural and microprobe data indicate that this spinel phase is associated with late iron-rich garnet (rim)-cordierite-sillimanite assemblage.
P-T conditions of cordierite-garnet assemblages vary from peak metamorphic conditions of greater than 8 kbar and 750°C to 6.7±1.4 kbar and 685 ±20°C. The last retrograde phase of metamorphism took place at P of 4.5 kbar and at T of 580°C. The formation of Zn and Cr rich spinel phase must have taken place during this waning stages of metamorphism by the activity of hydrothermal fluids.
On the Intrusive Suite from Biharpur, Madhya Pradesh
Authors: Ghosh Kaushik K. , Ray Jyotisankar , Nandy Keya 
Published: November 2024

Abstract
The intrusive suite comprises gabbro, dolerite (with hornblende-bearing variant), diorite and granitoids with both porphyritic and non-porphyritic types. A calc-alkaline character, on the acid intrusives is evident. Genetic link amongst the gabbro-dolerite-diorite intrusive members is suggested. The granitoid intrusives, on the other hand. appear to have no direct genetic lineage.
Petrology of the Proterozoic Alkaline Carbonatite Complex of Samalpatti, District Dharmapuri, Tamil Nadu
Authors: Srivastava Rajesh K. 
Published: November 2024

Abstract
The gneissic rocks of Samalpatti area are intruded by the Proterozoic carbonatites, alkaline rocks, pyroxenites and minor dunites. Mineralogically carbonatites show wide variations in their composition but chemically most of them are silico-carbonatites. Presence of hornfelsic textures and metamorphic minerals like chlorite, scapolite, diopside and grossularite, suggest metamorphism of the present carbonatites. Alkaline rocks are either syenites or lamprophyres. Both carbonatites and alkaline rocks are generally enriched in large-ion lithophile elements (LILE) and high-field strength elements (HFSE) relative to the primordial mantle. Although carbonatite samples have lower concentration of LILE and HFSE than the average values of known carbonatites, they fall within the range of magmatic carbonatite concentrations. Lower concentrations of these elements are a result of hydrothermal metamorphism by hot fluids.
Carbonatites are also enriched in d13C and d18O-values. The Rayleigh fractionation together with post-magmatic secondary processes, particularly exchange with magmatic fluids of high d18O content, are the best explanation for the C and 0 isotope enrichments. The carbonatites and alkaline rocks have probably crystallized from the carbonate and silicate melts separated from a postulated carbonated nephelinitic magma by Iiquid immiscibility at shallow levels.
FTIR Study of Lower Gondwana Coal from Talcher, Orissa
Authors: Misra S. K. , Mohanty J. K. , Nanda B. 
Published: November 2024

Abstract
Functional groups and mineral matters in Talcher coal have been identified with the help of FTIR. Oxygen bearing functional group mostly hydroxyl is common in bulk as well as different lithotypes. Minerals such as kaolinite, quartz, goethite etc. have been identified from the spectra. The functional groups data have been used to interpret the conditions of formation of the different lithotypes.
Kyanite-Phlogopite-Clinochlore Association in the Pelitic Rocks of the Vaikrita Group and the Haimanta Formation, Satluj Valley, Himachal Himalayas
Authors: Vir Pushpendra , Misra Jai K. , Mukhopadhyay Dilip K. 
Published: November 2024

Abstract
We report an unusual association of kyanite-phlogopite-clinochlore from the psammo-pelitic rocks occurring in the Higher Himalayas along the Satluj river between Shongtong and Morang, Himachal Pradesh. These rocks supposedly belong to the Vaikrita Group and the Haimanta Formation.
Co-Existing Pyroxenes from the Ferrosyenites of Sivamaiai, Tamil Nadu, South India
Authors: Ratnakar J. , Leelanandam C. 
Published: November 2024

Abstract
The ferrosyenites of Sivamalai (Tamil Nadu, South India) contains ortho- and clinopyroxenes in addition to fayalitic olivine, quartz, palgioclase, orthoclase perthite and opaques. The orthopyroxene occurs as (a) submicroscopic rim around fayalite, (b) exsolved (001) and (100) lamellae within clinopyroxene and (c) discrete blebs close to clinopyroxene. The composition of orthopyroxene among the analysed samples varies from eulite to orthoferrosilite and that of clinopyroxene from ferroaugite to ferrohedenbergite. The ortho- and clinopyroxenes individually exhibit systematic intraspecimen and intralintergranular variations of Fe and Mg, with a restricted range of Ca. The Fe/(Fe+Mg) ratios in the pyroxenes (0.966-0.722) indicate their consistency iron-rich nature, and the orthopyroxenes, in particular. are among a few extremely iron-rich ones reported.
The occurrence of orthopyroxene lamellae within clinopyroxenes of ferrosyenites of Sivamalai is a diagnostic feature of slow cooling of a tholeiitic magma. The two compositional trends defined by the pyroxenes in the quadrilateral suggest strongly fractionated nature of the liquid. The mineral assemblage fayalite+quartz+ferrosilite-rich orthopyroxene suggests a minimum P of 6 kb. The Sivamalai pyroxenes are considered to have formed at -740°C and 7 kb. These pyroxenes are presumably crystalllized from a Fe-rich acidic liquid under low fO2, moderate to high P and increasing SiO2.
Characteristics of Manganite (?-MnOOH) in Manganese-Rich Gangpur Group of Rocks, Orissa
Authors: Mohapatra B. K. , Nayak B. R. 
Published: November 2024

Abstract
Manganite ?-MnOOH, in the manganese-rich rocks of Precambrian Gangpur Group, Sundargarh district, Orissa, shows dissimilar fabrics and belongs to three generations but has more or less similar chemical composition. It occurs as patchy inclusions, accicular crystallites, egg-shaped micro-nodules, medium to coarse-grained mosaics, vein and fissure fillings and as wedge-shaped linings. The manganite is either formed froin Mn-oxide (jacobsite and vredenburgite) phases through retrogressive metamorphic transformation (Ma1) or generated through pseudomorphic replacement of Mn-sillicate (rhodonite and tcphroite) or Mn-carbonate (rhodochrosite) by chemical weathering under supergene conditions (Ma2). The vein filling type is the latest in its paragenesis (Ma3). Despite different mineral lineages, manganites are chemically similar though crystallites located in veins and fissures are relatively pure.