We report the mineralogy and high precision microprobe trace element data of olivine from the Mes... more We report the mineralogy and high precision microprobe trace element data of olivine from the Mesoproterozoic, diamondiferous P3 kimberlite in the Wajrakarur Kimberlite Field (WKF), southern India. Olivine macrocrysts in the kimberlite exhibit a core–rim structure which offers an opportunity to examine the variation in their minor and trace element (Ni, Ca, Al, Ti, Mn, Cr and Na) contents in order to differentiate melt-derived olivines from mantle olivines and also to distinguish multiple populations of mantle olivines.
Chromitite samples were collected from a core from the Katpal chromite mine of Sukinda chromite f... more Chromitite samples were collected from a core from the Katpal chromite mine of Sukinda chromite field for characterization of mineralogy especially the platinum group minerals (PGM). Isotope dilution with High Pressure Asher (HPA-ID) technique has been used in this study to evaluate its ability to determine compositions from small quantities of sample (two grams of sample). Enrichment of Iridium group of platinum elements (IPGE) (Ir ~ 1717 ng/g; Ru ~ 20 ng/g) at depth of ~ 35-80 m in the investigated core suggests the presence of a strong potential zone for IPGE mineralization. The obtained data suggests similarities with the ‘Reef-type’ mineralization. Key words: Platinum group minerals (PGM), high pressure asher acid digestion (HPA-ID), iridium group of platinum elements.
Data science has been an invaluable part of the COVID-19 pandemic response with multiple applicat... more Data science has been an invaluable part of the COVID-19 pandemic response with multiple applications, ranging from tracking viral evolution to understanding the vaccine effectiveness. Asymptomatic breakthrough infections have been a major problem in assessing vaccine effectiveness in populations globally. Serological discrimination of vaccine response from infection has so far been limited to Spike protein vaccines since whole virion vaccines generate antibodies against all the viral proteins. Here, we show how a statistical and machine learning (ML) based approach can be used to discriminate between SARS-CoV-2 infection and immune response to an inactivated whole virion vaccine (BBV152, Covaxin). For this, we assessed serial data on antibodies against Spike and Nucleocapsid antigens, along with age, sex, number of doses taken, and days since last dose, for 1823 Covaxin recipients. An ensemble ML model, incorporating a consensus clustering approach alongside the support vector machine model, was built on 1063 samples where reliable qualifying data existed, and then applied to the entire dataset. Of 1448 self-reported negative subjects, our ensemble ML model classified 724 to be infected. For method validation, we determined the relative ability of a random subset of samples to neutralize Delta versus wild-type strain using a surrogate neutralization assay. We worked on the premise that antibodies generated by a whole virion vaccine would neutralize wild type more efficiently than delta strain. In 100 of 156 samples, where ML prediction differed from self-reported uninfected status, neutralization against Delta strain was more effective, indicating infection. We found 71.8% subjects predicted to be infected during the surge, which is concordant with the percentage of sequences classified as Delta (75.6%–80.2%) over the same period. Our approach will help in real-world vaccine effectiveness assessments where whole virion vaccines are commonly used.
Hydrocarbon exploration and production are going on in Barmer basin (Rajasthan, India) formore th... more Hydrocarbon exploration and production are going on in Barmer basin (Rajasthan, India) formore than a decade. The potential source rocks are of Paleocene – Eocene age, and Mesozoicsiltstones form the reservoirs. The western and central portions of the Rajasthan basin arecharacterised by extensive lignite formations, which can be promising for artificialtransformation to oil and gas. We study the source rock properties, depositional environmentsand hydrocarbon generation potential of the Paleogene lignitic shales of the Giral lignite mineand the Cretaceous Sarnu siltstones for their source and reservoir rock potentiality. The totalorganic carbon content (TOC) of the Giral samples range between 0.76-49.83 wt% and thethermal maturity, as reflected by the pyrolysis Tmax, lies between 412-468 ℃. Sarnoo siltstones,on the other hand, have a very low TOC ranging from 0.02-0.08 wt% and a Tmax of 320-608 °C.The higher TOC and a lower oxygen index (OI) of Giral lignites and shaly lignites indi...
The Dharwar craton of southern India hosts a well preserved association of Archean granite greens... more The Dharwar craton of southern India hosts a well preserved association of Archean granite greenstone terranes and Proterozoic mafic dike swarms. Hitherto, the mafic dikes reported from the Dharwar craton, regardless of their occurrence in the eastern or western sector, are either tholeiitic or picritic and invariably contaminated by the Archean upper continental crust. In continuance to the previous study, this paper provides a rare account on the petrogenetic aspects of a Paleo-proterozoic crustally uncontaminated mafic dike "Dike 3" of alkaline affinity. Geochemically the rocks are basaltic in composition and mineralogically consist of clinopyroxene (Ti-augite), Na-rich plagioclase (oligoclase-andesine) as major silicate mineral phases while titaniferous magnetite ± ülvospinel are the opaque mineral oxides. The samples are characterized by strongly fractionated rare earth element (REE) patterns with elevated light-REE (La/Yb)N ~10 and depletion in the heavy-REE (Gd/Yb)N...
Abstract Soluble polycyclic aromatic hydrocarbons (PAHs) have been measured in Mukundpura (MK) CM... more Abstract Soluble polycyclic aromatic hydrocarbons (PAHs) have been measured in Mukundpura (MK) CM2 carbonaceous chondrite using Gas Chromatography-Mass Spectrometry (GC-MS). The data show high yields of PAHs with the presence of 2, 3, and 4 ring polycyclic aromatic hydrocarbons along with heterocyclic nitrogen and sulfur-containing compounds. MK also shows the presence of significant amount of alkylation products. The distribution and relative abundances of PAHs in the MK are discussed in context of its petrographic grade and correlation with aqueous alteration.
Scapolite occurrences are widely observed in the metasedimentary rocks exposed around the Khetri ... more Scapolite occurrences are widely observed in the metasedimentary rocks exposed around the Khetri Copper Belt and adjoining Nim ka Thana copper mineralized area in western India. Amoeboidal to well-developed and rounded/elliptical-shaped marialitic scapolite (Na-rich end-member) rich zones with variable Cl contents ranging from 1.0 wt % to 2.9 wt % have been identified in proximity to the ore-bearing hydrothermal fluid activity zones. Although scapolite is formed as a product of regional metamorphism in many places, in this study, we propose a strong possibility that scapolite was formed by hydrothermal ore-bearing fluid interaction with metasediments. The evidence of hydrothermal activity and Cl sourcing is attributed to (i) the absence of evaporite beds in the area and no Na-rich plagioclase as inclusions within the scapolite suggesting the formation of marialitic scapolite from sodic plagioclase in the metasediments with the interacting hydrothermal fluid; (ii) an epithermal to me...
We report a new zircon U–Pb age of 1257 ± 6 Ma for the Punugodu granite (PG) pluton in the Easter... more We report a new zircon U–Pb age of 1257 ± 6 Ma for the Punugodu granite (PG) pluton in the Eastern Dharwar Craton (EDC), Southern India. The Mesoproterozoic PG is alkali feldspar hypersolvus granite emplaced at shallow crustal level, as evident from the presence of rhyodacite xenoliths and hornfelsic texture developed in the metavolcanic country rocks of the Neoarchaean Nellore Schist Belt (NSB). Geochemically, the PG is metaluminous, ferroan and alkali-calcic, and is characterized by high SiO2 and Na2O + K2O, Ga/Al ratios >2.6, high-field-strength elements and rare earth element (REE) contents with low CaO, MgO and Sr, indicating its similarity to anorogenic, alkali (A-type) granite. The highly fractionated REE patterns with negative europium anomalies of PG reflect its evolved nature and feldspar fractionation. Mafic (MME) to hybrid (HME) microgranular enclaves represent distinct batches of mantle-derived magmas that interacted, mingled and undercooled within the partly crystal...
We report the mineralogy and high precision microprobe trace element data of olivine from the Mes... more We report the mineralogy and high precision microprobe trace element data of olivine from the Mesoproterozoic, diamondiferous P3 kimberlite in the Wajrakarur Kimberlite Field (WKF), southern India. Olivine macrocrysts in the kimberlite exhibit a core–rim structure which offers an opportunity to examine the variation in their minor and trace element (Ni, Ca, Al, Ti, Mn, Cr and Na) contents in order to differentiate melt-derived olivines from mantle olivines and also to distinguish multiple populations of mantle olivines.
Chromitite samples were collected from a core from the Katpal chromite mine of Sukinda chromite f... more Chromitite samples were collected from a core from the Katpal chromite mine of Sukinda chromite field for characterization of mineralogy especially the platinum group minerals (PGM). Isotope dilution with High Pressure Asher (HPA-ID) technique has been used in this study to evaluate its ability to determine compositions from small quantities of sample (two grams of sample). Enrichment of Iridium group of platinum elements (IPGE) (Ir ~ 1717 ng/g; Ru ~ 20 ng/g) at depth of ~ 35-80 m in the investigated core suggests the presence of a strong potential zone for IPGE mineralization. The obtained data suggests similarities with the ‘Reef-type’ mineralization. Key words: Platinum group minerals (PGM), high pressure asher acid digestion (HPA-ID), iridium group of platinum elements.
Data science has been an invaluable part of the COVID-19 pandemic response with multiple applicat... more Data science has been an invaluable part of the COVID-19 pandemic response with multiple applications, ranging from tracking viral evolution to understanding the vaccine effectiveness. Asymptomatic breakthrough infections have been a major problem in assessing vaccine effectiveness in populations globally. Serological discrimination of vaccine response from infection has so far been limited to Spike protein vaccines since whole virion vaccines generate antibodies against all the viral proteins. Here, we show how a statistical and machine learning (ML) based approach can be used to discriminate between SARS-CoV-2 infection and immune response to an inactivated whole virion vaccine (BBV152, Covaxin). For this, we assessed serial data on antibodies against Spike and Nucleocapsid antigens, along with age, sex, number of doses taken, and days since last dose, for 1823 Covaxin recipients. An ensemble ML model, incorporating a consensus clustering approach alongside the support vector machine model, was built on 1063 samples where reliable qualifying data existed, and then applied to the entire dataset. Of 1448 self-reported negative subjects, our ensemble ML model classified 724 to be infected. For method validation, we determined the relative ability of a random subset of samples to neutralize Delta versus wild-type strain using a surrogate neutralization assay. We worked on the premise that antibodies generated by a whole virion vaccine would neutralize wild type more efficiently than delta strain. In 100 of 156 samples, where ML prediction differed from self-reported uninfected status, neutralization against Delta strain was more effective, indicating infection. We found 71.8% subjects predicted to be infected during the surge, which is concordant with the percentage of sequences classified as Delta (75.6%–80.2%) over the same period. Our approach will help in real-world vaccine effectiveness assessments where whole virion vaccines are commonly used.
Hydrocarbon exploration and production are going on in Barmer basin (Rajasthan, India) formore th... more Hydrocarbon exploration and production are going on in Barmer basin (Rajasthan, India) formore than a decade. The potential source rocks are of Paleocene – Eocene age, and Mesozoicsiltstones form the reservoirs. The western and central portions of the Rajasthan basin arecharacterised by extensive lignite formations, which can be promising for artificialtransformation to oil and gas. We study the source rock properties, depositional environmentsand hydrocarbon generation potential of the Paleogene lignitic shales of the Giral lignite mineand the Cretaceous Sarnu siltstones for their source and reservoir rock potentiality. The totalorganic carbon content (TOC) of the Giral samples range between 0.76-49.83 wt% and thethermal maturity, as reflected by the pyrolysis Tmax, lies between 412-468 ℃. Sarnoo siltstones,on the other hand, have a very low TOC ranging from 0.02-0.08 wt% and a Tmax of 320-608 °C.The higher TOC and a lower oxygen index (OI) of Giral lignites and shaly lignites indi...
The Dharwar craton of southern India hosts a well preserved association of Archean granite greens... more The Dharwar craton of southern India hosts a well preserved association of Archean granite greenstone terranes and Proterozoic mafic dike swarms. Hitherto, the mafic dikes reported from the Dharwar craton, regardless of their occurrence in the eastern or western sector, are either tholeiitic or picritic and invariably contaminated by the Archean upper continental crust. In continuance to the previous study, this paper provides a rare account on the petrogenetic aspects of a Paleo-proterozoic crustally uncontaminated mafic dike "Dike 3" of alkaline affinity. Geochemically the rocks are basaltic in composition and mineralogically consist of clinopyroxene (Ti-augite), Na-rich plagioclase (oligoclase-andesine) as major silicate mineral phases while titaniferous magnetite ± ülvospinel are the opaque mineral oxides. The samples are characterized by strongly fractionated rare earth element (REE) patterns with elevated light-REE (La/Yb)N ~10 and depletion in the heavy-REE (Gd/Yb)N...
Abstract Soluble polycyclic aromatic hydrocarbons (PAHs) have been measured in Mukundpura (MK) CM... more Abstract Soluble polycyclic aromatic hydrocarbons (PAHs) have been measured in Mukundpura (MK) CM2 carbonaceous chondrite using Gas Chromatography-Mass Spectrometry (GC-MS). The data show high yields of PAHs with the presence of 2, 3, and 4 ring polycyclic aromatic hydrocarbons along with heterocyclic nitrogen and sulfur-containing compounds. MK also shows the presence of significant amount of alkylation products. The distribution and relative abundances of PAHs in the MK are discussed in context of its petrographic grade and correlation with aqueous alteration.
Scapolite occurrences are widely observed in the metasedimentary rocks exposed around the Khetri ... more Scapolite occurrences are widely observed in the metasedimentary rocks exposed around the Khetri Copper Belt and adjoining Nim ka Thana copper mineralized area in western India. Amoeboidal to well-developed and rounded/elliptical-shaped marialitic scapolite (Na-rich end-member) rich zones with variable Cl contents ranging from 1.0 wt % to 2.9 wt % have been identified in proximity to the ore-bearing hydrothermal fluid activity zones. Although scapolite is formed as a product of regional metamorphism in many places, in this study, we propose a strong possibility that scapolite was formed by hydrothermal ore-bearing fluid interaction with metasediments. The evidence of hydrothermal activity and Cl sourcing is attributed to (i) the absence of evaporite beds in the area and no Na-rich plagioclase as inclusions within the scapolite suggesting the formation of marialitic scapolite from sodic plagioclase in the metasediments with the interacting hydrothermal fluid; (ii) an epithermal to me...
We report a new zircon U–Pb age of 1257 ± 6 Ma for the Punugodu granite (PG) pluton in the Easter... more We report a new zircon U–Pb age of 1257 ± 6 Ma for the Punugodu granite (PG) pluton in the Eastern Dharwar Craton (EDC), Southern India. The Mesoproterozoic PG is alkali feldspar hypersolvus granite emplaced at shallow crustal level, as evident from the presence of rhyodacite xenoliths and hornfelsic texture developed in the metavolcanic country rocks of the Neoarchaean Nellore Schist Belt (NSB). Geochemically, the PG is metaluminous, ferroan and alkali-calcic, and is characterized by high SiO2 and Na2O + K2O, Ga/Al ratios >2.6, high-field-strength elements and rare earth element (REE) contents with low CaO, MgO and Sr, indicating its similarity to anorogenic, alkali (A-type) granite. The highly fractionated REE patterns with negative europium anomalies of PG reflect its evolved nature and feldspar fractionation. Mafic (MME) to hybrid (HME) microgranular enclaves represent distinct batches of mantle-derived magmas that interacted, mingled and undercooled within the partly crystal...
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