bluuebunny/crossref_metadata_2025_split huggingface dataset:
Textural and Geochemical Studies of Relict and Modern Sediments of the Continental Shelf Off Honavar, West Coast of India
Authors: Narayana A. C. , Prabhu Venkatesh 
Published: November 2024

Abstract
The textural and geochemical studies of shelf sediments off Honavar reveal three types of sedimenents - modern, relict and mixture. Modern sediments are present in the inner as well as outer shelf regions. The midshelf region mostly consists of relict sands. In general, the distribution pattern of Cu and Ni shows the zonal pattern as that of three types of sediments i.e., modern, relict and mixture. Cu, Ni, and Zn show high positive correlation with organic matter. Factor analysis reveals that the sedinients were derived from a terrigenous source and deposited in an oxidizing environment.
Maskelynite from the Indian Impact Crater at Lonar
Authors: Nayak V. K. 
Published: November 2024

Abstract
Maskelynite recognized in coarse grained shocked basalt fragments in monomiet breccia from the ejecta debris on the eastern side of the LonarImpact Crater, has been investigated. Maskelynite occurs with pyroxenes, opaques and preserves porphyritic texture. Maskelynite laths of various sizes are colourless, clean and show planar features. Its An-content varies from An66 to An69 which closely corresponds to labradorite, is optically isotropic and has an average refractive index 1.560 ± 002. Heating experiments revealed that maskelynite revets to a crystalline state at 800°C. The mechanisms of plagioclase-maskelynite transformation in an impact environment and reversion to plagioclase on heating are discussed.
Application of Seismic Stratigraphy in Oil Exploration with Examples from Western Offshore
Authors: Kutty P. S. N. , Agarwal V. K. 
Published: November 2024

Abstract
Seismic stratigraphic methods have been applied as a tool in exploration for hydrocarbons in west coast basins over a long period. Some of these methods have been utilised in the present study to identify potential targets for drilling. Such methods were used for mapping wedge out prospects in East Mahim area and the periphery of Bombay high. The development of porosity within limestone has been inferred by studying the seismic attribute namely Amplitude and pseudoimpedance on 3D and 2D seismic data. The extent of hydrocarbon bearing sands has been mapped by calibrating the character of the sands with the vertical seismic profiling data at the well and carrying it laterally.
Paleoceanographic Implications of Planktonic Foraminiferal Abundance at DSDP Sites 219,220 and 241 - An Approach Based on Paleontologic Time Series
Authors: Sarkar Ashish , Guha Asit K. 
Published: November 2024

Abstract
Paleontologic Time Series (PTS) analysis in both time and frequency domains on eight series of abundance data of Globorotalia menardii and total planktonic foraminifera from top core sections of DSDP Sites 219, 220 and 241 of Northern Indian Ocean depict cyclic variation presumably due to fluctuations in the Pleistocene paleo-temperature. At these sites, the relative dominance of planktonic foraminifera and G. menardii, uniform effect of post-mortem transport on foraminiferal tests of different sizes and differential sediment accumulation rate are revealed from the nature of energy distribution in the spectra, identical nature of major peaks and varying cycle lengths respectively.
Determination of Epicenter and Comparison of some Empirical Formulae with Observed Data of Acceleration from Two Events in Himalaya
Authors: Das J. D. , Chandrasekaran A. R. 
Published: November 2024

Abstract
Two earthquakes of April 26 and September 10 were recorded by strong motion array's in India during the year 1986 by Kangra and ShilIoog array respectively. Mean peak horizontal accelerations are in the range of 157 to 2217 mm/sec in case of the April event, whereas it is 163 to 1234 rnmlsec2 for the September one.
Epicentral information (DEQ) has been derived using P and S wave arrival times of strong motion accelerograph stations and compared with that reported by IMD and USGS. Epicentral distance and focal depth are better indicated by the strong motion array data. Focal parameter obtained for the earthquakes differ from that reported by USGS. For the April earthquake, USGS epicenter (E2) lies around 10 km southeast of DEQ epicenter (E3). Focal depth obtained in this study is only around 7 km against 33 km given by USGS. But in the case of the September event epicenter location by DEQ (E3) and USGS (E2) lie close to each other but focal depths were different around 28 km (DEQ) against 43 km (USGS). Error parameters, like RMS, ERH, ERZ are very low in both the cases.
McGuire's and other empirical formulae were used to estimate acceleration at a particuIar site. For the April event McGuire's estimate is very close to tbe observed acceleration when DEQ hypocenter was taken into consideration. However, accelerations estimated for the September event do not conform to the observed ones, eventhough some values are quite cIose.
Response of the Southern Indian Peninsula to Mesozoic-Cenozoic Activation
Authors: Thakur N. K. , Nagarajan Nandini 
Published: November 2024

Abstract
Tectonics controlled evolution of deep crustal exposures have recently attracted much attention. The southern part of Peninsular India, consisting of highgrade metamorphic rocks, sandwiched between converging rifted margins, shows characteristically different geophysical signatures as compared to other geologically similar provinces. Based on geophysical anomalies and the tectonic framework of the region it is proposed that the subsurface structural configuration beneath the granulite terrain of South India has been perturbed by Meso-Cenozoic rifting at the continental margins and consequent crust-mantle dynamics.
Present Day Geomorphic Processes as Key to the Reconstruction of Quaternary Landform History in the Thar Desert
Authors: Kar Amal 
Published: November 2024

Abstract
Most of the studies on the Quaternary landform evolution in the Thar are devoted to broad morphological processes, the changing climate and absolute daring of different episodes of sedimentation. Reconstruction of actual sequence of events which led to the development of many present day forms and the role of neotectonism have received relatively less attention. The author, during his traverses in the desert, came across certain evidences to suggest that a knowledge of present day process - form interactions may provide significant clues to the possible past processes. A few examples have been cited.
New Find of Tungsten Mineralisation Near Balepalyam and other areas of Ramagiri-Penakacherla Schist Belt, Anantapur Dist, A.P.
Authors: Koti Reddy B. B. , Reddy K. N. , Desikan N. 
Published: November 2024

Abstract
Promising zones of tungsten are reported for the first time in Ramagiri-Penakacherla schist hell at Atmahru, Balepalyam and Penukonda areas. The mineralisation occurs as disseminations, tringers and fracture fillings of scheelite. Fourteen scheelite bearing quartz-pegnlatite veins have been delineated in Balepalyam block. WO3 values range from 10 ppm to 5.86%. The association of other clrments like tin, antimony, arsenic, gold and bismuth suggest a possible minerological zoning and multimetal prospects in the schist belt.
Cretaceous Sedimentation in the Sub-Surface of Krishna-Godavari Basin
Authors: Mohinuddin S. K. , Satyanarayana K. , Rao G. N. 
Published: November 2024

Abstract
The NE-SW trending Krishna-Godavari Basin is located at right angles to NW-SE trending Pranhita-Godavari graben ? towards the basin margin. From subsurface exploratory data obtained, it is inferred that NW-SE trending Gondwana graben is .extending underneath Krishna-Godavari Basin. In subsurface, the sedimentary sequence occurring in between the basalt and the ' Red Bed ' is demarcated as the Cretaceous sequence. This sequence is further divisible into three litho-units as equivalents to Gollapalli sandstone, Raghavapuram shale and Tirupati sandstone.
The depositional environment for Gollapalli sandstone is interpreted to be mainly fluvial towards NW of Tanuku horst and paralic towards SE of the horst. The Raghavapuram shales were deposited under marine conditions. The upper part of Tirupati sandstone is of fluvial nature around Kommugudem area and changes gradually to paralic and to marine towards the southeastern part of the Basin.
Reservoir Induced Microearthquakes Around Tarbela Dam, Pakistan Himalaya
Authors: Chander Ramesh , Sarkar Irene 
Published: November 2024

Abstract
The Tarbela reservoir is situated on the lndus river in the Pakistan Himalaya. A telemetred seismic network has been in operation around the reservoir site since 1973, about a year prior to its initial impoundment. Recently, a detailed statistical investigation of post-impoundment seismicity around this rcservoir for a period of seven years has been reported in the literature. Evidence has been presented there for relatively high probability of increased microearthquake activity at shallow depths in the crust beneath the Tarbela reservoir during periods of low water levels. We argue that, although this is important evidence on the question of whether reservoir induced seismicity can occur in the Himalaya, there is need for further detailed seismicity observations around the present and future reservoir sites in these mountains.
Recent Ostracoda of the Tekkali Creek, East Coast of India
Authors: Varma K. U. , Shyam Sunder V. V. , Naidu T. Y. 
Published: November 2024

Abstract
Twenty-five ostracode taxa are recorded from the Tekkali Creek, East Coast o f India. Of these the following three new spxies are describ:d in detail: Hemicyiheridea bhatiai, Loxoconcha tekkaliensis and Neomnonoceratina jaini, while Neosinocyihcre dekrooni and Paijenborchella (Eopaijenborchella) mlaiensis are being reported for the first time from the Indian waters.
The Century-Old Problem of the Pali-Parsora-Tiki Stratigraphy and its Bearing on the Gondwana Classification in Peninsular India
Authors: Dutta Prodip K. , Ghosh Santosh K. 
Published: November 2024

Abstract
The stratigraphic relationship between the Pali-Parsora-Tiki formations in the South-Rewa Gondwana basin remains unresolved after more than a century. We believe that this is primarily related to the flawed methodology used in addressing Ihe problem. The stratigraphic soIulion was, exclusively, lied to fossil-based age data which is an interprelative element in any stratigraphic analysis. Field relationships such as lithological associations, petrological character and order of superposition that contradicted the fossil-based stratigraphy were ignored. The contradictions, however, were explained by "Conjectual" faults, also an interpretative criterion that was invoked to explain the stratigraphy. The conventional hierarchical approach to stratigraphy, beginning with physical criteria followed by biostratigraphy and chronostratigraphy, was missing.
The sequence encompassing the Pali, Tiki, and Parsora formations can be divided into two well defined lithostratigraphic units. A feldspathic sandstone-red mudstone association characterizes both the Pali and Tiki formations and is considered, in this paper, as a single lithostratigraphic unit. Tentatively and informally, the unit is named as Pali-Tiki Formation. The second unit, a quartzose sandstone-conglomerate and variegated clay association typifies the Parsora Formation. The Pali-Tiki Formation can be traced almost continuousIy from the Pali area to Tiki village. The field relation clearly demonstrates that the Parsora unconformably overlies the Pali-Tiki.
Based on vertebrates, plants and palynological criteria, the Pali-Tiki formation has been assigned latest Permian/Early Triassic to Middle Norian age. The Parsora Formation spans from a little above Middle Norian to well within Early Jurassic. The Glossopteris flora that flourished in the Permian continues across the Permo-Triassic boundary into the Pali-Tiki Formation. The Dicroidium flora appears at the base of the Pali-Tiki Formation and demarcates the Permo-Triassic transition. In the Parsora Formation both Glossopteris and Dicroidium floral assemblages are present and extend, at least, up to the Early Jurassic. These observations go against the fundamental tenet of a two-fold classification scheme for the Gondwana System in peninsular India. This work supports a three-fold classification for the Gondwana system, solely based on floral content. If the floral elements are taken away, the physical straligraphers can make a strong case for a two-fold division based on lithology, petrography and the widespread unconformity throughout peninsular India. A unified classification scheme using both biological and physical pilrameters does not seem to work.
Rb-Sr Ages on the Granite and Pegmatitic Minerals from Bastar-Koraput Pegmatite Belt, Madhya Pradesh and Orissa, India
Authors: Ramesh Badu P. V. , Pandey B. K. , Dhana Raju R. 
Published: November 2024

Abstract
isotopic date on 12 samples of the Paliam and Darba granites of the Bastar Craton in Central India have defined an isochron age of 2308 ± 48 Ma. with initial Sr-isolopic ratio of 0.7354 ± 0.0097. Mineral ages on perthite, biolile and muscovite from tin- and rare metal-minearlised as well as non-minearlised pegmatites of the Bastar-Koraput Pegmatite belt within this craton have indicated two important dates of about 2050 and 1620 Ma. These dates are interpreted as (a) emplacement of the granite around 2300 Ma., (b) derivation of the pegmatites from this parent granite around 2050 Ma and (c) reselling of Rb-Srsystem at about 1620 Ma., concomitant with the metamorphic/uplift event in the nearby Eastern Ghats. The very high initial 87Sr/86Sr ratio of 0.735 for granite indicates thai they are crustal derived, possibly from a metasedimentary source.
Departures from True Ellipticity of Principal Sectional Boudin Shapes and their Mechanical and Kinematic Implications
Authors: Roday Prakash P. , Katpatal Yashwant B. 
Published: November 2024

Abstract
Any ?1 ?3 principal sectional boudin shape is considered to depart from the ideal ellipse and its overall shape could be described in terms of the average four values of the exponent, p, one for each quadrant. Based on this, some principal shapes and their geometrical variations are characterised and possible mechanical and kinematic significance of each shape outlined. The values of the exponent, p, were calculated using a digital computer.
Complexation of Fluoride Ions with Alum-Flocs at Various pH Values during Coagulation and Flocculation
Authors: Raju D. V. , Janardhana Raju N. , Kotaiah B. 
Published: November 2024

Abstract
Complexation of fluoride ions by the addition of lime and alum to fluoridc-spiked tap water was investigated at varying pH values through the Jar-test technique. The results obtained indicate that the optimum pH for higher complexation of fluoride ions with alum-floc will range from 5.8 to 6.3 depending upon the amount of fluoride present in the solution. Hydrogen bonding on polynuclear complexes of partially hydrolyzed Al(III) as well as physical sorption of F- ions on Al (OH)3(s) floes by Van der waal's forces are the possible mechanisms for F- ion removal from water.
Petrological Status of Hornblende Quartzite and Associated Rocks of Basantgarh Area of Sirohi District, Rajasthan
Authors: Munshi R. L. 
Published: November 2024

Abstract
Petrographic and petrochemical study of the reported metagreywacke/hornblende quartzite band near Basantgarh reveals compositional variation along its length. The band is made of both igneous and metasedimentary rocks which are represented by Ieucocratic amphibolite, gneisses and schists. Chemically the leucocratic amphibolite is similar to the plagiogranites and possibly derived by differentiation of a melt which was protolith for the metabasites of the area.
Petrographic and Magnetic Studies of a Columnar Sill and a Dyke from the Deccan Traps
Authors: Subbarao K. V. 
Published: November 2024

Abstract
A critical petrographic investigation together with magnetic studies such as the variation of susceptibility with temperature and hysteresis have been carried out on basalt samples drilled across a dyke and a columnar sill from the Deccan Traps. In the case of columnar basalts, not much variation has been found in the grain size but display increase in shattering of the grains towards the edge of the column. In contrast, the dyke samples are tachylitic at the edge grading to fine-grained basalt in the middle.
The magnetic hysteresis studies indicate an increase of single-domain (SO) mineral grains from the margin to the centre of the columnar basalt. Low temperature susceptibility studies clearly indicate Ihe presence of some multidomain (MD) componcnt of pure magnctite in the cdge samples where as it is barely noticeahle in the s.1l1lple from the cenlre. Samples from the dyke show systematic variations of rhe magnetic parameters. These magnetic variations can be undcrstood in terms of titanomagnctite composition and domain states of thc grains among samples from across the dyke.
Lobachevskian Inversion as a Tool for Better Feature Detection in Structural Analysis
Authors: Krishnakumar K. R. , Rao S. V. L. N. 
Published: November 2024

Abstract
When conventional methods of curve-fitting for the contoured plots on an equal area net fail to be satisfactory. Lobachevskian inversion may be performed on the original plots and finally the inverted plots can be regressed to a straight line for validating the accuracy of the best-fitting arc.
Early Miocene Radiolarian and Planktonic Foraminiferal Biostratigraphy, North Passage Island, Andaman Sea
Authors: Sharma V. , Srinivasan M. S. , Mahapatra A. K. 
Published: November 2024

Abstract
The Early Miocene sequences of North Passage Island iu the Andaman Sea have been studied for their siliceous and calcareous microfossil assemblages. 95 species of radiolaria and 27 species of planktonic foraminifera belonging to these two major groups of microfossils have been documented. An integrated radiolarian ancl planktonic foraminifera1 biostratigraphy is presented.
Size Frequency Distribution of Quartz Sand Particles in Untransported Sediments: Its Significance
Authors: Patro B. C. 
Published: November 2024

Abstract
The arithmatic probability plots of Size Frequency Distribution (SFD) of untransported in-situ quartz sand accumulations (herein called the 'in-situ sediment'), at the top, slope and foot of a quartzite ridge, generated by thermal disintegration of the source rock (quartzite) show 2 to 4 straight line segments indicating the presence of 2 to 4 log normally distributed sub-populations. The phi standard deviation, sf,increases with decreasing size of the sub-populations indicating a smaller size-spread in coarser sub-populations and wider size-spread in finer sub-populations. These results are shown to be in cornplete consonance with the modus operandi of thermal disintegration. Sand grains of 1.00 mm and finer sizes are shown to be recalcitrant to thermal disintegration. The semblance in the pattern of SFD curves of in-situ sediment as well as those of detrital sediments reader the reliability of the SFD curves as discriminators of transportational/depositional environments questionable.
Geochemistry and Petrogenesis of the Champawat Granitoids Occurring around Dhunaghat, District Pithoragarh, Uttar Pradesh, India
Authors: Singh B. N. , Goel O. P. , Joshi Mallickarjun , Sheraton J . W. 
Published: November 2024

Abstract
Early Cambrian Champawat granitoids from Dhunaghat area, emplaced between medium-to high-grade metapelites of the Saryu Formation and low-grade melapelites of the Gumalikhet Formation of the Almora Group, show wide variations in their modal and chemical composition, ranging from granodiorite to granite. Biotite-rich mafic enclaves within the granitoids may represent restile, possibly modified by metasomatism. Chemical data for the calc-alkaline Champwat granitoids show some dcgree of fractional crystallization, although processes such as restite unmixing and different degree of melting may also have been important for the observed variation trends.
The Champwat intrusives are also characterized by enrichment of Y, Zr, Th, U, Nb, La, Ce, Pr and Nd and show affinities with "A"-type (anorogenic) granites.
Sea Levels Along Visakhapatnam Coast: A Geomorphic Explanation
Authors: Prudhvi Raju K. N. , Khan Ahmed Raza , Ramesh Y. 
Published: November 2024

Abstract
About 120 km of shoreline in north coastal Andhra Pradesh on either side of Visakhapatnam is rocky with a number of headlands aad bays. Surfaces and caves in rocks along this shoreline were mapped, to explain their relation to sea level stands of Holocene. The physiographic status of surfaces at several locations was worked out in terms of their number and area versus altitude. The seaward margins of hills mapped at many sites along the southern part of the shoreline show a distinct orientation of the outline and dominance of a class of surfaces different from those along the northern stretch. This variability is attributed to the concentration and release of energy of longshore drift and to the variable orientation of the shoreline. Surfaces between elevations of 5 and 1 metre above msl dominate the shoreline. The geomorphic characteristics of these surfaces conform well with those of the storm wave platforms. Sea caves are very few and are associated with either horizontal and/or inclined joints or foliation planes. The 'inactive' cliffs with their toes at about 2 metres above msl along with rocky floors/surfaces with sand cover, point to a sea level stand of 1.00-1.50 metres above the (present) mean low tide level (mltl).
Late Eocene-Early Oligocene Biostratigraphy of Mansa-Indrora Area, Cambay Basin
Authors: Jaiprakash B. C. , Kumar P. 
Published: November 2024

Abstract
Late Eocene-Early Oligocene succession from two well sections of north-eastern margin of Cambay Basin was analysed for their foraminifera1 content. It has yielded rich larger foraminifera a few planktonic and benthonic foraminifera. Three larger foraminiferal biozones have been recognised for the succession in geologically ascending order. These are Nummulites fabianii Partial Range Zone (? 39.4 m.y. to 37.4 m,y., i.e., ? P 15 to 16); Discocyclina dispansa - Nummulites fabianii Concurrent Range Zone (37.4 m.y. to 36 m.y.. i.e., Zone P 17) and Nummulites fichteli Partial Range Zone (36 m.y. to? 35 m.y., i.e., Zone P18), The environment of deposition has varied from shallow marine to inner and outer shelf conditions in the course of the development of the succession.
On the Occurrence of Uvigerina danvillensis and Hantkenina trinidadensis from Cambay Basin
Authors: Jaiprakash B. C. , Raju D. S. N. 
Published: November 2024

Abstract
Uvigerina danvillensis Howe and Wallace and Hantkenina trinididecrsis Bronnimann are described and illustrated from Late Eocene succession of Cambay basin. The presence of these two species at two levels indicates possible incursions of moderately deep marine conditions in an inner shelf set-up.
Granulometric Analyses of Pelites Using a Sedigraph: Examples from a Volcano-Sedimentary Environment
Authors: Mascarenhas Antonio 
Published: November 2024

Abstract
This article presents granulometric data of pelites (less than 40 microns) of mixed composition from a volcano-sedimentary environment. The Sedigraph serves as an useful tool in the analyses of silt-clay fraction of marine sediments. A cumulative curve from 40 to 1 micron can be obtained in 20 minutes. Pelites analysed show wide variations in grain size characteristics with the median value oscillating between 22 and 3 microns. In general, two fine grain size facies, each showing significant variations, are deciphered. Parabolic facies represents coarse silts whereas logarithmic facies comprise medium to fine silts. The type of grain size curves largely depends on the abundance of carbonate and pyroclastic mineral content of individual pelites. As compared to total pelites, their decalcified fractions sometimes show a significant shift of the grain median towards finer sizes. The intricacies of grain size studies of pelites of mixed composition are described in this paper.