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Geochemistry and depositional environment of fuchsite quartzites from Sargur Group,western Dharwar Craton,India

Acta Geochimica 2024年第3期43卷 555-570页

作者： C.S.Sindhuja G.Harshitha C.Manikyamba K.S.V.Subramanyam csir(Council of Scientific and Industrial Research)-National Geophysical Research Institute(NGRI) Uppal RoadHyderabad 500007India

Meso-Neoarchean fuchsite quartzites are present in different stratigraphic positions of Dharwar Craton including the oldest(~3.3 Ga)Sargur Group of western Dharwar *** present study deals with the petro-graphic and geochemical characteristics of the fuchsite quartzites from the Ghattihosahalli belt to evaluate their genesis,depositional setting and the enigma involved in the ancient sedimentation *** major mineral assemblages include quartz,fuchsite,and feldspars along with accessory kyanite and *** geochemical com-positions are characterized by high SiO_(2),Al_(2)O_(3),low MgO,CaO,strongly enriched Cr(1326–6899 ppm),Ba(1165–3653 ppm),Sr(46–210 ppm),V(107–868 ppm)and Zn(11–158 ppm)contents compared to the upper continental crust(UCC).The UCC normalized rare earth element(REE)patterns are characterized by depleted light REE[(La/Sm)UCC=0.33–0.95]compared to heavy REE[(Gd/Yb)_(UCC)=0.42–1.65]with conspicuous positive Eu-anomalies(Eu/Eu^(*)=1.35–18.27)characteristic of hydrothermal solutions evidenced through the interlayered *** overall major and trace element systematics reflect a combined mafic-felsic provenance and suggest their deposition at a passive continental margin *** comprehensivefield,petrographic,and geo-chemical studies indicate that these quartzites are infiltrated by Cr-richfluids released during high-grade metamorphism of associated ultramafic *** Sargur and the subse-quent Dharwar orogeny amalgamated diverse lithounits from different tectonic settings,possibly leading to the release of Cr-richfluids and the formation of fuchsite quartzite during or after the *** sug-gest a pre-existing stable crust prior to the Sargur Group and the link between orogenic events and various mineral deposits in the Dharwar Craton.

关键词： Dharwar Craton Ghattihosahalli Fuchsite quartzite Provenance Depositional setting

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Geochemistry and mineral chemistry of the armoor granitoids,eastern dharwar craton: implications for the redox conditions and tectono-magmatic environment

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Acta Geochimica 2024年第1期43卷 110-133页

作者： A.Ajay Kumar Ch.Ashok Department of Geology Osmania UniversityHyderabad 500007India csir-National Geophysical Research Institute UppalHyderabad 500007India

The mineralogical and geochemical characteristics of the K-rich granites from the Armoor granitic rocks in the northeastern portion of the Eastern Dharwar Craton(EDC) are *** order to understand its physicochemical conditions,the petrogenesis of the granitoid was explained from biotite chemistry and geochemical *** of mineral chemistry expose that compositionally,K-feldspar and plagioclase in Armoor granite rocks range from An0,Ab_(3-5.9),Or_(94-96.9) and An_(5-29,-Ab71.9-94.9),Or_(0-1.5),*** mineral chemistry of biotite crystals exhibits composition that varies from primary to re-equilibrated primary *** biotites from the Armoor granites generally exhibit an I-type trend,with calc-alkaline parental magma in a subduction *** chemistry of granites displays magnetite(oxidized)series nature,which has oxygen fugacity(fO_(2))=-15.1 to-16.7(log_(10) bar),under high oxidizing *** and pressure estimates for the crystallization of Armoor granites based on biotite composition are T=612-716 ℃ and 1.0-0.4 kbar,***,these rocks are metaluminous to slightly peraluminous and magnesian,with calc-alkaline potassiumrich *** the chondrite normalized REE diagram,the granites have positive europium anomalies;rich Sr/Y,(Dy/Yb)_(N) ratios and reduced Mg#,Rb/Sr,Rb,Sr indicate that the melting of earlier rocks,crystal accumulation and residual garnet source formed at high *** examined granites show that they are produced from the melting of crustal ***,the extensive analyses of the described Armoor granite suggest that they were produced by crust sources and developed under oxidizing conditions in subduction setting.

关键词： Armoor granites Oxygen fugacity Crystal accumulation Remelting Subduction

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Sustainability Issues Related to the Engineering Geology of Long Linear Developments

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Journal of Mountain Science 2011年第2期8卷 321-327页

作者： PAIGE-GREEN Philip csir built environment Pretoria 0001 South Africa

The development of long linear structures such as roads, rail roads, tunnels, canals and pipelines often has unique engineering geology challenges. These include geological modeling, the identification of material strength and support factors, stability and risk issues, material excavation characteristics and the proposal of techniques for overcoming geotechnical problems, which are normally assessed as part of the conventional engineering geological investigation. An additional factor that is becoming increasingly important but is seldom included in investigations is the sustainability of the geotechnical inputs, in contrast to the sustainability of the project which is generally included. Sustainability issues revolve around the non-renewable nature of most construction resources and there is no doubt that the injudicious use of these construction materials and construction water is not sustainable in the long term: it is thus essential that the engineering geo-logical investigation should take cognizance of such issues and be adapted to provide the design engineer with the information that will maximize the sustainability options. This will also require a closer on-going relation-ship between the engineering geologist and the design engineer. This paper highlights significant sustainability issues (note that these differ from conventional environmental issues) and suggests some mitigating solutions. The sustainability issues discussed include primarily material and water usage, with some reference to energy conservation (mostly through alternative material usage and processing techniques and transportation).

关键词： Engineering geology Sustainability Linear structures Construction material Water

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Geochemical and petrological studies of high sulfur coal and overburden from Makum coalfield (Northeast India) towards understanding and mitigation of acid mine drainage

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International Journal of Coal Science & Technology 2024年第1期11卷 133-147页

作者： Angana Mahanta Debashis Sarmah Nilotpol Bhuyan Monikankana Saikia Sarat Phukan K.S.V.Subramanyam Ajit Singh Prasenjit Saikia Binoy K.Saikia Coal and Energy Division CSIR-North East Institute of Science and TechnologyJorhatAssam785006India Academy of Scientific&Innovative Research(Acsir) Ghaziabad201002India Department of Geological Sciences Gauhati UniversityGuwahatiAssam781014India Geochemistry Division CSIR-National Geophysical Research InstituteUppal RoadHyderabad500007India

Opencast coal mining produces trash of soil and rock containing various minerals,that are usually dumped nearby the abandoned sites which causes severe environmental concern including the production of acid mine drainage(AMD)through oxidation pyrite *** current study entailed assessing the potential production of AMD from an opencast coal mining region in Northeast part of *** order to have a comprehensive overview of the AMD problem in Makum coalfield,the physico-chemical,geochemical,and petrological characteristics of the coal and overburden(OB)samples collected from the Makum coalfield(Northeast India)were thoroughly *** maceral compositions reveal that coal features all three groups of macerals(liptinite,vitrinite,and inertinite),with a high concentration of liptinite indicating the coal of perhydrous,thereby rendering it more ***(FeS_(2))oxidation kinetics were studied by conducting the aqueous leaching experiments of coal and(OB)samples to interpret the chemical weathering under controlled laboratory conditions of various temperature and time periods,and to replicate the actual mine site *** coupled plasma-optical emission spectroscopy(ICP-OES)was operated to detect the disposal of some precarious elements from coal and OB samples to the leachates during our controlled leaching *** Rare earth element(REE)enrichment in the samples shows the anthropogenic incorporation of the REE in the coal and *** experiments reveal the change in conductivity,acid producing tendency,total dissolved solid(TDS),total Iron(Fe)and dissolved Sulfate(SO_(4)^(2−))ions on progress of the leaching ***,the discharge of FeS_(2) via atmospheric oxidation in laboratory condition undergoes a significant growth with the rise of temperature of the reaction systems in the environment and follows pseudo first order kinetics.A bio-remediative strategies is also reported in this paper to mitigate AMD water by

关键词： Opencast mining Pyrite oxidation Coal geochemistry Coal petrology Rare earth elements AMD remediation

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Fuel properties and emission characteristics of biodiesel produced from unused algae grown in India

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Petroleum Science 2018年第2期15卷 385-395页

作者： Rachan Karmakar Krishnendu Kundu Anita Rajor School of Energy and environment Thapar University Department of Biofuel CSIR CMERI CoEFM

The high price of different biodiesels and the need for many of their raw ingredients as food materials are the main constraints to be overcome when seeking the best potential alternative fuels to petro-diesel. Apart from that, some properties like high density, viscosity and acid value along with low cloud and pour points preclude their use in com- pression ignition （CI） engines as these properties can cause serious damage to the parts of the engine and reduce engine life. In this experiment, biodiesel was produced from the oil of unused algae by a two-step ＇acid esterification followed by transesterification＇ procedure. Taguchi＇s method was applied to design the experiment, and a L25 orthogonal array was prepared to optimize the biodiesel production procedure. The optimized conditions for transesterification were： methanol to oil molar ratio of 6：1, catalyst （KOH） concentration of 2.5 wt%, reaction time of 90 min and reaction temperature of 50 ~C, achieving a biodiesel production of 89.7% with free fatty acid content of 0.25%. It was found that the CI engine emitted less CO, CO2 and hydrocarbon and higher NOx using algal biodiesel than that using petro-diesel. All properties of the algal biodiesel were within the limit of ASTM standards.

关键词： Algae Biodiesel Fuel characterization Emission

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Textural and geochemical characteristics of off shore sediment of North Bay of Bengal:A statistical approach for marine metal pollution

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International Journal of Sediment Research 2015年第3期30卷 208-222页

作者： Sanghamitra Palleyi Sabnam Banoo Rabi Narayan Kar Chitta Ranjan Panda environment & Sustainability Department CSIR-Institute of Minerals and Materials Technology

Metal pollution study on sediments of North Bay of Bengal sediments presented in this paper is based on existing Lithostratigraphy of upstream,mineralogy and geochemical analysis of 42 sediment *** statistical analysis identifies the metal pollution as well as its apparent source in the off shore *** were analyzed for grain size,organic content and heavy metals(Fe,Mn,Cr,Cu,Ni,Pb,Cd,Zn and Co) using the sequential extraction method to evaluate geochemical processes and pollution *** an effort to surmise anthropogenic input,several approaches including classification by quantitative indexes such as enrichment factor,contamination factor,degree of pollution,pollution load index and geo accumulation index,were *** speciation results indicate high%of Cd in exchangeable fraction of Mahanadi transect sediments where as a considerable amount of oxidizable fraction of Cr was detected at *** indexes place North Bay of Bengal under moderately polluted zone due to high level of *** of metals to Fe indicated relatively high enrichment factors for Cd and *** analysis identified seven possible types of geochemical associations where sediment pH plays a major role for the heavy metal *** higher Cd concentration in exchangeable fraction as well as the higher EF for Cd and Cr present in sediment may pose a risk of secondary water pollution under slightest disturbance in the geo-chemistry of *** study with available data of near costal zones and upstream stratigraphy revealed that open cast mining,overburden dumping,mineral based industrial effluents were the major source of pollution for catchment area *** of Bengal is likely to face a serious threat of metal pollution with the present deposition rates unless rigorous pollution control norms are applied.

关键词： North Bay of Bengal Heavy metals Sequential extraction Quantitative index Factor analysis

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Differences in Tree Species Diversity and Soil Nutrient Status in a Tropical Sacred Forest Ecosystem on Niyamgiri Hill Range,Eastern Ghats,India

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Journal of Mountain Science 2012年第4期9卷 492-500页

作者： Sudam Charan SAHU Nabin Kumar DHAL Brij LAL Rama Chandra MOHANTY environment and Sustainability Department CSIR-IMMTBhubaneswar-751013India Biodiversity Division CSIR-IHBTPalampurIndia Department of Botany Utkal UniversityBhubaneswar-751004India

We have quantitatively analyzed the tree species diversity with respect to soil nutrient status in three sites of a sacred forest ecosystem of Niyamgiri hill range, Eastern Ghats, India. Extensive field surveys and sampling were conducted in 3 sites of the hill range： Site 1 Pterocarpus dominated forest （PTF）（19°40＇02.2＇＇ N and 83°21＇23.1＇＇ E）, Site 2 Mangifera dominated forest （MAF）（19°40＇02.8＇＇ N and 83°21＇40.8＇＇ E） and Site 3 Mixed forest （MIF）（19°36＇47.1＂ N and 83°21＇02.7＇＇ E）. A total of 28 families, 42 genera, 46 tree species, and 286 individual trees were recorded on an area of0.6 ha. Tree density varied between 470 and 49o individuals ha and average basal area between 3.16 and l0.04 m2 ha-1. Shannon Index （H＇） ranged from 2.34 to 4.53, Simpson＇s Index ranged from 0.07 to o.09, and equitability Index ranged from 0.7 to 1.34. The number of individuals was highest in the girth at breast height （GBH） class of 50-7o cm. The soil nutrient status of the three forest types was related to tree species diversity. The soil pH value of the three sites reflected the slightly acidic nature of the area. Species diversity was positively correlated with organic carbon and phosphorus and negatively with nitrogen, EC and pH. The results of the current study may be helpful to further develop a conservation planfor tree species in tropical sacred forest ecosystems.

关键词： Tree species diversity Sacred forestecosystem Soil nutrient status Eastern Ghats

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Estimation of food composition of Hodotermes mossambicus （Isoptera： Hodotermitidae） based on observations and stable carbon isotope ratios

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Insect Science 2011年第2期18卷 175-180页

作者： Craig T. Symes Stephan Woodborne School of Animal Plant and Environmental Sciences University of the Witwatersrand Wits Natural Resources and the environment CSIR Pretoria South Africa

The diet of the harvester termite Hodotermes mossambicus was investigated at two sites with distinct dietary components： C4 grasses （δ13 C isotope values, -13.8%0 to -14.0%0） and C3 plants （δ13C isotope values, -25.6%0 to -27.1%0）. By comparing observations of food items carried into the colony by the termites and carbon isotope ratios of whole termites （that determined assimilated carbon）, the relative proportion of the C3 and C4 plant food components of the termite diet was estimated. There was agreement between the observational data and stable carbon isotopic data, with grass representing approximately 93% of the diet ofH. mossambicus at two study sites （urban and rural） on the South African highveld. However, when correcting for mass of food items, that is, C3 and C4, carried by termites, the proportion of grass （C4） in the diet may be underestimated.

关键词： carbon assimilation colony harvester termite Suikerbosrand

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Use of non-timber forest products from invasive alien Prosopis species(mesquite) and native trees in South Africa: implications for management

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Forest Ecosystems 2015年第3期2卷 197-207页

作者： Ross T Shackleton David C Le Maitre Brian W van Wilgen David M Richardson Centre for Invasion Biology Department of Botany and ZoologyStellenbosch University Centre for Invasion Biology Natural Resources and the EnvironmentCSIR

Background: Prosopis species have been introduced to many areas outside their native range to provide benefits to local communities. Several Prosopis species and their hybrids(hereafter "mesquite") have, however, become naturalised and invasive and now generate substantial costs. Management options are limited because of the complex conflicts of interest regarding benefits and costs. Management policies and strategies must take account of such conflicts, but further insights are needed on the dimensions of uses and impacts before such information can be usefully applied. Current policy in South Africa allows for the growth and use of mesquite in one province,but not in others where its control is mandatory. We report on a study to quantify the direct use and perceptions of non-timber forest products(NTFPs) from mesquite and native trees in South ***: Semi-structures household interviews were conducted with various stakeholder groups to identify what tree products are used, to ascertain amounts used as well as to gauge perceptions of natural resource use between different tree species and use over ***: The direct household use value of native trees was higher than that of mesquite, and local stakeholders attached greater value to products from native trees than from mesquite. Therefore, native trees are and will still be preferentially harvested, and mesquite is unlikely to offer protection to native species by providing an alternative source of products. Mesquite pods do, however, provide valuable additional resources(fodder and medicinal products). The use of both native trees and mesquite is decreasing as the incomes of poorer households rise and as alternative energy sources become available. The benefits and reliance on mesquite are not as high as previously assumed and the impacts from mesquite invasions create large problems for local ***: This study provides further evidence that the impacts of mesquite exceed the benefi

关键词： Biological invasions Conflicts of interests Cost v

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Production of biodiesel from unused algal biomass in Punjab, India

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Petroleum Science 2018年第1期15卷 164-175页

作者： Rachan Karmakar Anita Rajor Krishnendu Kundu Nitin Kumar School of Energy and environment Thapar University Department of Biofuel CSIR CMERI Co EFM Department of Mechanical Engineering Thapar University

Biodiesel from inedible sources has become prominent in last few decades. But it is economically incompatible with petroleum diesel. At the same time, both petro-diesel and biodiesels are concerned with environmental pollution, global warming, etc. Algae, on the other hand, utilize CO2 for their growth and can minimize some sort of pollution level and results in carbon credit for a country. In Punjab, India, algae are seen to grow in many water bodies. But all those are taken away and dumped in vats. Some of this huge biomass was used for production of biodiesel in this work. Extraction of oil from algae was conducted by using Soxtherm（solvent extraction）. An amount of 9 wt% of algal oil was extracted by comparatively costly hexane, whereas 8% extraction was done by cheaper acetone. In the transesterification reaction, molar ratio（methanol： oil） of 6：1, catalyst（KOH） concentration of 3 wt%, reaction temperature of 60 °C, 60 min reaction time and a settling time of 2.5 h were found to be optimum conditions to get maximum ester with minimum free fatty acid content and viscosity. A statistical analysis for the transesterification procedure also showed a methanol-to-oil molar ratio of 6：1 and catalyst concentration of 3 wt% to be the optimum. Characterization of biodiesel was done and compared with ASTM/BIS standards. Most important properties of biodiesel ester like viscosity（3.12 c St or 3.12 mm2/s）, cloud and pour point（-1 and-6 °C, respectively）, flash and fire point（153 and 158 °C）, carbon residue content（0.03%）, acid number（0.36 mg of KOH/gm） were within the range of concerned standards.

关键词： Algae Biodiesel Biodiesel properties Transesterification Oil extraction

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