bluuebunny/crossref_metadata_2025_split huggingface dataset:
Crustal Reflectivity Parameter for Deciphering the Evolutionary Processes Across the Proterozoic Aravalli-Delhi Fold Belt
Authors: Tewari H. C. , Rajendra Prasad B. , Vijaya Rao V. , Reddy P. R. , Dixit M. M. , Madhava Rao N. 
Published: November 2024

Abstract
Deep Continental Reflection Studies along the Nagaur-Jhalawar profile across the Aravalli-Delhi Fold Belt indicate that in most of the units comprising the seismic profile the lower crust (LC) lies towards west of their present surface exposures. Based on the reflectivity characteristics of the LC. which are in general agreement with the globally accepted norms, the Nagaur-Jhalawal profile can be broadly divided into five zones: 1) the moderately reflective Marwar Basin (MB), 2) the highly reflective Delhi Fold Belt (DFB), 3) the poorly reflective Bhilwara Granite Complex (BGC), 4) the highly reflective Hindoli Group (HG) including a thrust zone, and 5) the moderately reflective Vindhyan Basin (VB). The most commonly accepted reasons for high lower crustal reflectively are: 1) presence of free fluids. 2) crustal-scale ductile shear zones and 3) mafic intrusions and underplating with partial melts derived from the upper mantle.
High reflectivity of LC in the ADFB can possibly be assigned to primary lithologic variation in the metamorphic facies layers and Precambrian shear zones that were formed during compressional phase of orogeny. The poor reflectivity of LC in the BGC. comprising the Sandmata and Mangalwar Complexes, may be due to vertically oriented igneous intrusions which have disturbed its lamellar character. The high reflectivity in the thrust zone and LC in the HG suggests that it is due to a totally different composition than that of BGC and may be related to metamorphic layering.
Calcretes : Geotechnical Appraisal and Efficacy as an Alternative Pavement Material for the Desertic Roads of Western Rajasthan
Authors: Ramakrishnan D. , Tiwari K. C. 
Published: November 2024

Abstract
Calcretes are widely distributed in the arid and semi-arid tracts of the Thar Desert. Strategically important roads of this desert region need a suitable, locally available paving material. Mineralogy, physical and geotechnical properties of calcretes indicate their suitability for road pavements.
Testimony of Intraformational Limestone Breccias on Lokapur-Simikeri Disconformity, Kaladgi Basin
Authors: Kale Vivek S. , Nair Sushma , Patil Shilpa 
Published: November 2024

Abstract
Detailed measurements of a more than 55 m wide tract of the Chikshellikeri Limestone, immediately underlying the Muchkundi Quartzite were undertaken in the Kaladgi Basin. This sequence is constituted of 3218 measured laminations from more than 1550 mudstone - packstone couplet. They are interrupted by 57 horizons of Intraformational Limestone Breccias. The distribution pattern of these horizons within the sequence is evaluated within the framework of the depositional environments which yielded the limestone sequence and they are recognised as products of events of penecontemporaneous basin-floor instability. It is shown that disconformity separating the Bagalkot Group into two Subgroups (earlier attributed to two separate transgresive events) was formed as a result of reorganisation of the basin configuration in response to synsedimentary tectonics and not as a result of a second transgression of the contemporary sea.
Saline Ground Water Management in Manda Thana of Naogaon District, NW Bangladesh
Authors: Woobaidullah A. S. M. , Ahmed K. M. , Hasan M. A. , Hasan M. K. 
Published: November 2024

Abstract
The study area is dependent on ground water for irrigation during the dry months of the year as sufficient surface water resources are not available. Occurrence of saline ground water in some parts of the area, particularly at Kashopara and Kasab unions. restricts the use of ground water for irrigation purposes. Ground water electrolytic conductivity (EC) monitoring and resistivity sounding show a distinct vertical ground water zoning with varying salinity, viz .. an upper zone (0-30 m) of relatively fresh Na/CaHCO3-type ground water with EC values &lt;1000 μS/cm and a lower zone (below 30 m) of NaCI-type (brackish) ground water with EC values &gt;2000 μS/cm. It is suggested that salinity prohlems in the affected area can be managed through minimum abstraction of saline ground water, proper selection of crops, land development and by changing methods of irrigation.
Palaeomagnetic Results from the Pleistocene-Holocene Lake Deposits of Bhimtal and Bhowali (kumaun Himalaya) and Lamayuru (Ladakh Himalaya) with Reference to the Reversal Events
Authors: Kotlia B. S. , Bhalla M. S. , Shah Nalin , Rajagopalan G. 
Published: November 2024

Abstract
Palaeomagnetic studies were carried out in the fluvio-Iacustrine sediments of Bhimtal and Bhowali basins (Kumaun Himalaya) and of Lamayuru basin (Ladakh Himalaya). The results were supplemented by radiocarbon dating. For the first time in the terrestrial sediments of the Quaternary-Holocene age in the Indian subcontinent, three minor reversal polarity events have been recorded at Lamayuru (ca. 35.5 ± 0.6 ka BP), Bhimtal (29.8-25.6 ka BP), and Bhowali (ca. 7.7 ± 0.13 ka BP). Since the upper most portion of the Lamayuru section indicated a reversal event, it may be significant to correlate it with the Indian Ocean event estimated as 40 ka BP. It is suggested that the Bhimtal event may be correlated with the widely known Mono Lake excursion which is fixed at 28-26 ka BP. Among the Holocene events, only a few are known, e.g., an event in the Solberga sediments (Sweden) estimated at ca. 10 ka BP; an event from Central Asia, dated at about 9 ka BP; the Erieau excursion, upper part of which has been estimated at about 7.6 ka BP; and the youngest event known as the Starno event (2.8 ka BP). The initial reports of the palaeomagnetic events, described in this paper, may be highly significant for examining several more sections as the events should he found repeatedly in sediments of same age in a given sedimentary environment.
Magnetostratigraphy of Fluviolacustrine Sediments from Pithoragarh Area, Uttar Pradesh
Authors: Bhalla M. S. , Kotlia B. S. , Subrahmanyam K. 
Published: November 2024

Abstract
Magnetostratigraphy of fluviolacustrine sediments from a 10 m thick section of a palaeolake near Wadda, Pithoragarh district, Uttar Pradesh bas been studied. The results indicate a prominent change in inclination of the remanent field in the age span 24 to 25 Ka, correlating with the widely known Mono lake excursion. Higher susceptibility values for the sediments of a part of the section are inferred to be due to rapid erosion rate associated with the transport of magnetite-rich sediments from the catchment area.
Calcareous Nannofossils Across the K/T Boundary and the Age of the Deccan Trap Volcanism in Southern India
Authors: Salis Katharina V. , Saxena R. K. 
Published: November 2024

Abstract
The distribution of calcareous nannofossils across the Cretaceous/Tertiary (K/f) boundary in well PLK-A in the Krishna-Godavari Basin of Southern India has been studied in the interval including sediments above, within and below the Deccan traps. With Micula murus present and M. prinsii missing, the presence of upper, but not uppermost Maastrichtian can be shown. The K/T boundary lies above trap flow 2 and the traps are overlain by sediments of the lower part of NP 3 (Danian). The span of volcanism has here probably lasted not more than 4 Ma.
Granites of Zoz Area, Baroda District, Gujarat and its Economic Significance
Authors: Maithani P. B. , Rathaiah Y. V. , Varughese Siby K. , Singh Rajendra 
Published: November 2024

Abstract
The granites around Zoz represent a differentiated, calc-alkaline, subaluminous, A-type granite with higher uranium content. The A-type affinity points to the possibility of encountering Sn, Mo, Bi, Nb, Ta and F mineralisation in the area. The low Th/U ratio also favours vein type U-deposits within granites or in adjacent metasediments.
Deformational History of Eastern Ghat Mobile Belt Around Lathore, Balangir District, Orissa
Authors: Biswal T. K. , Sanjeevan G. , Nayak B. P. 
Published: November 2024

Abstract
The calc-gneiss and garnet-sillimanite-gneiss of Eastern Ghat Mobile Belt around Lathore bear the imprint of multiple phases of deformtion. The folds of the first generation, F1, are isoclinal, intrafolial and vary in style from reclined to upright. This has developed a pervasive axial planar gneissosity. The second generation folds, F2 , which are coaxial with the F1 are open to tight with a planar axial surface dipping moderately to SE and varied plunging axis. At places mesoscopic plane non-cylindrical F2 sheath folds are noticed. Gentle upright folds, F3 , with NW-SE striking axial plane represent structure of third generation. Superimposition of F2 on F1 has resulted in Type 3 interference pattern and dome and basin structures are due to the interference of F2 and F3 folds. F1 and F2 folds are attributed to WNW-ESE buckling and F3 is reported to be due to shortening across it. The 'sheath folds' are due to heterogeneous simple shear aiong the axial plane of the F2 fold. The map shows a large scale southwesterly plunging overturned F2 fold. Post-exhumation deformation has resulted in brittle shearing parallel to the axial plane of F2 fold. The structure of the area points to a collisional tectonic setting like other granulite belts of Gondwanaland.
Jabalpur Earthquake of May 22, 1997: Constraint from Aftershock Study
Authors: Acharyya S. K. , Kayal J. R. , Roy A. , Chaturvedi R. K. 
Published: November 2024

Abstract
Macroseismic and microseismic (aftershock) investigations were carried out by the Geological Survey of India immediately after the Jabal pur earthquake (M 6.0) of May 22, 1997. The meizoseismal area of an intensity VIII (MSK) is 35 km long and 15 km wide, trending ENE-WSW. The aftershock investigation was earned out by a five-station temporary microearthquake (MEQ) network. Five felt aftershocks (M=3.0) and 23 aftershocks in the magnitude range 1.5 to &lt; 3.0 were recorded by the network. These are mostly clustered in an elongated area, 15 ×10 krn, near the main shock epicentre. and occurred at a depth range 35-40 k.m which is compatible with that of the main shock. The fault-plane solution of the main shock and the aftershocks revealed reverse faulting with left-lateral strike-slip component The hypocentral section and the fault-plane solutions indicate that the pre-existing ENE-WSW trending Nannada South Fault is deep-rooted to mantIe depth, and has been activated at the crust-mantle boundary to produce the main shock and the aftershocks. The failure appears to be caused in response to the northward post collisional movement of the Indian plate.
Reaction Textures of Retrograde Pressure-Temperature-Deformation Paths from Granulites of Schirmacher Hills, East Antarctica
Authors: Ravikant V. , Kundu Amitava 
Published: November 2024

Abstract
A retrograde path inferred for the Schirmacher Hills granulites involves near ITD path following post-peak granulite facies metamorphism (M1/D1), preserved only in enclaves, followed by near IBC path, M3, post dating M2/D2 granulites facies metamorphism and deformation. Final uplift and cooling of the terrain occurred in the upper amphibolite facies metamorphic conditions, M4, syntectonic with respect to D3 deformation and emplacement of large volume of syntectonic granitoids. Fluids released during cooling and crystallization of these granitoids probably caused the large scale retrogression of granulite facies rocks to amphibolite facies gneisses.
On the Genesis of Indian Beryls
Authors: Narendra Babu K. , Sebastian Ansom 
Published: November 2024

Abstract
Beryl samples collected from pegmatites of Bihar, Rajasthan, Andhra Pradesh and Kerala. Showed marked correlations between chemical constituents and physical parameters. The following are the major observations of this study: (i) Specific gravity and refractive index vary with alkali elements, (ii) unit cell dimensions vary with divalent metal ions and alkali elements, (iii) Be content correlates with refractive index, unit cell dimension c and also with Li content. Beryl samples are alkali-poor and form two distinct populations with alkali concentration of 0.594-0.863 wt% and 1.468-1.871 wt%. These two chemical types of beryls possibly tally with two generations, one of primary zones and the other of late phase cleavelandite. The data also showed that the analysed beryls from Indian pegmatites contain extremely low concentrations of rare alkalies. Correlation of Al with divalent metal ions; and Be with Li signifies that both octahedral and tetrahedral substitutions can take place in these beryls. In the structural formula the sum (Al3++Me2+), in all cases, showed close proximity to 2 justifying octahedral substitution.
Stratigraphic and Sedimentologic Evolution of the Proterozoic Siliciclastics in the Southern Part of Chhattisgarh and Khariar, Central India
Authors: Datta Basudeb 
Published: November 2024

Abstract
The Proterozoic siliciclastic successions in the southern part of Chhattisgarh around Panduka village, Raipur dt., Madhya Pradesh and in the northern part of Khariar plateau around Nawapara, Nawapara (North Kalahandi) dt., Orissa consist of three comparable formations namely, the Lohardih, the Chaporadih and the Kansapathar Formations of the Chandarpur Group of the Chhattisgarh Supergroup. The evolution of the sedimentary successions in both the areas follows identical succession of events, i.e., an initial progradation and a subsequent transgression-regression phase. Palaeoslope of both the areas was towards south/southeast and the palaeo-shoreline trend was ENE-WSW to NNE-SSW. Marine transgression occurred from southeast. Environmental and palaeocurrent analyses suggest that the siliciclastic successions at Panduka and Khariar, separated by a wide stretch of crystallines, developed in different parts of the one and same basin, the Panduka area represents the proximal part whereas the Khariar plateau represents the distal part.
Genus Thalmannita (Foraminifera) from the Niniyur Formation (Paleocene), Ariyalur Area, South India
Authors: Malarkodi N. , Nagaraj H. M. 
Published: November 2024

Abstract
Thalmannita in the South Indian Paleocene, outside the West European and Tethyan biogeographic realms, is recorded for the first lime. The genus has two existing species madrugaensis and hajeezi. The following four new species are added namely, Thalmannita niniyurensis n.sp. T. adanakurchchensis n.sp., T. gowdai n.sp. and T. sastryi n.sp. The Thalmannita is a well known guide fossil of the Paleocene age.
Deformation Structures in the Subathu Rocks, Dogadda Area, Garhwal Himalaya
Authors: Agarwal K. K. 
Published: November 2024

Abstract
The shale-siltstone sequence of the Subathu Formation in the Dogadda area shows three main types of deformation structures, namely (i) small cleavage duplex, (ii) pencil structures, and (iii) cleavage refraction in the mesoscopic open folds. The development of these structures without a pervasive fabric and syntectonic recrystailisation of phyllosilicates could be assigned to deformation under subaerial conditions. The whole deformation pattern seems to be the result of advancement of crystalline thrust wedges over the Lesser Himalayan sedimentary rocks.
Platinum Group Elements in REE-Th-Zr-Ti-Rich Tremolite-Actinolite Rock from Vattalakki, Palghat District, Kerala
Authors: Dhana Raju R. , Vijayalakshmi S. , Mahalingam T. R. , Rao C. R. M. , Roy Madhuparna 
Published: November 2024

Abstract
Platinum Group Elemental (PGEs-Pt, Ir, Pd, Rh and Ru) contents, determined by ICP-MS, are reported in a rare REE-Th-Zr-Ti-rich ultrabasic tremolite-actinolite rock from Vattalakki, Kerala. Data on PGE, together with unusually high contents of REE, Th, Zr and Ti at percent level, indicate this rock as 'anomalous'.
Occurrence of Gabbro-Anorthosite Intrusive, Ramdaspeta, Anantapur District, Andhra Pradesh
Authors: Suresh G. , Srinivasan K. N. , Roopkumar D. , Rao N. V. 
Published: November 2024

Abstract
A linear body of gabbro-anorthosite has been recognised as a syn-to-late kinematic intrusion within the calc-alkaline granitoid suite of the Eastern Dharwar Craton, having the characteristics of layered mafic intrusion (LMI) and major oxide composition similar to massif type anorthosite.
Splenial and Vomerine Dentitions of Pycnodont Fishes from the Upper Part of the Subathu Formation (Middle Eocene), Malyuriyan, Rajauri District, Jammu and Kashmir
Authors: Thappa B. D. , Raina B. K. , Prasad G. V. R. 
Published: November 2024

Abstract
Intensive search for vertebrate fossils in the Eocene Subathu Formation, Kalakot, Jammu and Kashmir has resulted in the recovery of one complete vomer, two splenials (one fairly complete and one fragmentary) and a number of isolated teeth of pycnodonts, a holostean group of fishes. The vomer is the first report of its kind from the Indian subcontinent. Based on dental morphology, size and length/width proportions of the teeth on individual tooth rows, the vomer and splenials are referred to two new species of Pycnodus: P. subathuensis and P. dattai, respectively.
Geochemistry of the Metavolcanics of the Hutti-Maski Schist Belt, South India: Implications to Gold Metallogeny in the Eastern Dharwar Craton
Authors: Giritharan T. S. , Rajamani V. 
Published: November 2024

Abstract
The Hutti-Maski schist belt in the eastern Dharwar craton consists predominantly of mafic metavolcanics metamorphosed to amphibolite facies. The amphibolites are tholeiitic in composition with higher abundances of iron and with flat to LREE enriched rare earth patterns. Modelling of major and trace elements suggests that the tholeiitic protoliths were formed from melt enriched mantle sources by different extents of partial melting at pressures -25 kbars. The most common mafic metavolcanics in the three auriferous schist belts of eastern Dharwar craton such as the Kolar. the Ramngiri and the Hutti belts are high-iron tholeiites with LREE enriched rare earth patterns. The gold mineralization in the form of quartz-carbonate veins in the three belts is commonly hosted in high irontholeiitic protoliths. The process of formation of Fe-rich tholeiites. their metamorphism to amphibolites and their subsequent emplacement along terrane boundaries could have provided a favourable geochemical environment for gold mineralization.
A Study of Inverted Metamorphism in the Higher Himalayan Yamuna Valley, Uttarkashi District, Uttar Pradesh
Authors: Biyani A. K. 
Published: November 2024

Abstract
The distinctive feature of the Higher Himalaya of Yamuna Valley is that with in the hanging wall greenschist metapellitic nappe, quartzite and marble of footwall are exposed both with inverted disposition of isograds in the eyelid windows. These Barrovian type syn- to post-tectonic events of metamorphism are recorded in the rocks. Chlorite to garnet zone paragenesis in metapelitic rocks and chlorite-biotite zone paragenesis in quartzite and marble are developed by stronger earlier event of metamorphism (M1). The second event of metamorphism (M2) is mild, followed by another feeble retrogressive event (M3). While inversion of isograds in metapelites is attributed to hot slab thrust over the cold, in quartzite and marble, evidences suggest additional role of shear heating and contact effect by a sub-surface cooling igneous body.
Trace Fossils from the Cambrian of Zanskar (Ladakh Himalaya) and their Stratigraphic Significance
Authors: Parcha S. K. 
Published: November 2024

Abstract
The Cambrian sequences exposed in the Kurgiakh Valley of the Zanskar area of Ladakh Himalaya contain a variety of trace fossils as in other Tethyan sequences of Himalayan region. The Ichnogenera identified from this sequence belongs mostly to the traces of trilobite origin, with other traces of arthropod and of unknown origin. These include the Ichnogeneras such as Rusophycus ; Cruziana; Monomorphichnus; Phycodes; Planolites; Skolithos; Meandering trails and trilobite scratch marks. The traces mostly belong to Early Cambrian to early Middle Cambrian in age and occur below the trilobite assemblage; few traces extend above the trilobite-bearing beds. The described species have been collected from the Kurgiakh Formation. The first appearance of species of Phycodes pedum has a special bearing on the identification of the beginning of Cambrian in the sequence. The present report of trace fossils from this Formation is the first report of trace fossils from this area of Ladakh Himalayan region.
Open System Fractional Crystallization Process in the Evolution of Deccan Basalts of Pratapgarh Region, Western India
Authors: Pandit M. K. , Srivastava R. K. 
Published: November 2024

Abstract
The northwestern fringe of the Deccan Flood Basalt sequence is characterized by isolated occurrences of sub-horizontal tholeiitic flows. Because the flow units in this region are not traceable over large distances, the petrographic and geochemical characters have been utilized to establish nine flow units of olivine tholeiite (OT), quartz tholeiite (QT) and low calcium quartz tholeiite (LCT). The flows show striking mineralogical and chemical similarity. Low-Mg numbers and moderate to high silica content indicate the derivative nature of the magma. The flow sequence has evolved through predominant plagioclase fractionation and less significant clinopyroxene separation from a non-primary olivine tholeiite melt from which olivine had been removed earlier. Cyclic variation in geochemical signatures and prominent chemical breaks within the flow sequence indicate a periodically replenished, open system, shallow level magma chamber with gabbroic fractionation.
Fluid Inclusion Characteristics of Tin Bearing Pegmatites of Malkangiri District, Orissa
Authors: Pal D. C. , Panigrahi M. K. , Mishra B. 
Published: November 2024

Abstract
Stanniferous pegmatites of Malkangiri occur both in metabasics and metasediments showing signatures of deformation but very little wall rock alteration. Fluid inclusion microthermometric studies in pegmatitic quartz and quartz from quartz veins reveal the following three types of inclusions: aqueous biphase, metastable (?) monophase aqueous inclusions which do not show any thermal response, and rare halite-bearing inclusions. The CO2-free nature of the inclusions is noteworthy. Isochores of halitebearing inclusions (where Ts Nacl &gt; Th) intersect at P-T values of 2.65 kb and 337°C, implying preservation of the magmatic fluid that separated during the late stage of felsic magmatism in the area. Additionally, the above P-T values compare reasonably well with those obtained from the intersection of halite liquidi with the corresponding isochores.
Tin-bearing pegmatites in metabasics are characterized by their low temperature of homogenization and isothermal variation in salinity. This is explained by mixing of a Sn-bearing, granite affiliated, presumably reduced fluid with a heated, less evolved oxygenated meteoric water that led to cassiterite precipitation. Interestingly, inclusions in cassiterite-bearing pegmatites within metasediments record a low temperature comparable with those from within metabasics. In contrast, barren pegmatites within the schistose metasediments preserve high temperature signature and indicate a simple cooling trend. The study reveals different styles of evolution of stanniferous and barren pegmatites at Malkangiri.