Author
C. Ishwar-Kumar
Bio: C. Ishwar-Kumar is an academic researcher from Indian Institute of Science. The author has contributed to research in topics: Suture (geology) & Zircon. The author has an hindex of 6, co-authored 9 publications receiving 187 citations.
Topics: Suture (geology), Zircon, Archean, Gneiss, Granulite
Papers
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TL;DR: In this article, the authors report detailed evidence for a new paleo-suture zone (the Kumta suture) on the western margin of southern India, which contains garnet-biotite, fuchsite-haematite, chlorite-quartz, quartz-phengite schists, biotite augen gneiss, marble and amphibolite.
79 citations
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TL;DR: In this article, the authors investigate the tectonic evolution of one of the northernmost block- the Biligiri Block (BRB) through a multidisciplinary approach involving field investigation, petrographic studies, LA-ICPMS zircon U-Pb geochronology, Hf isotopic analyses, metamorphic P-T phase diagram computations, and crustal thickness modeling.
37 citations
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TL;DR: In this paper, the elastic thickness (Te) and Moho depth data were used to estimate the configuration of the Moho/Crust-Mantle Interface that reveals regional correlations with the thickness variations.
35 citations
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TL;DR: In this article, the authors present the results from an integrated study of the structure, geology, petrology, mineral chemistry, metamorphic P-T conditions, zircon U-Pb ages and Lu-Hf isotopes of metasedimentary rocks from the two sutures.
29 citations
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TL;DR: In this paper, the age of a monazite-leucosome experiment at 800 degrees C and 2 kbar has been shown to be within the error bars of a mean age of 530 Ma within error bars.
25 citations
Cited by
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TL;DR: In this article, the authors present an actualistic tectonic division and evolution of the North China Craton based on the Wilson Cycle and comparative analysis that uses a multi-disciplinary approach to define sutures, their ages, and the nature of the rocks between them, to determine their mode of formation and means of accretion or exhumation.
253 citations
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TL;DR: In this article, the authors present the petrology, geochemistry, zircon U-Pb geochronology and Lu-Hf isotopes of all the major lithologies from the Coorg block.
210 citations
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TL;DR: The Dharwar Craton formed by assembly of micro-blocks with independent thermal records and accretionary histories is analyzed in this paper, which provides important insights into building of continents in the Early Earth.
179 citations
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TL;DR: In this article, a multidisciplinary study involving field, petrographic, SHRIMP U-Pb zircon/titanite ages, whole rock geochemical and Nd-Sr isotope data is presented for the Peninsular Gneisses and associated plutons forming core of the Dharwar craton.
133 citations
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TL;DR: In this article, the four REE-minerals (Monazite, xenotime, allanite and apatite) are used as geochronometers.
Abstract: ### REE-minerals
Monazite, xenotime, and allanite are REE1-minerals sensu stricto because lanthanides (La…Lu) and yttrium are critical constituents in them Apatite does not require REE, but because it contains substantial REE in many rocks, it is included in this review All four minerals also host unusually high radionuclide concentrations, notably Th and U, forming the basis of their utility as geochronometers
This quartet of accessory minerals is playing an increasingly important role in petrochronology because they provide ways to link robust spot ages to petrogenetic ( P–T ) conditions so can lend petrogenetic context to chronology based on other minerals Part I of this review assembles the basic requisites prior to integrative petrochronologic analysis Individual characteristics of the four REE-minerals are addressed first, ie, their crystal chemistry and stability relations Thermobarometers and trace element geochemistry used for tracing petrogenesis are discussed next, and finally their chronology is summarized Part II presents case studies to highlight the specific strengths of REE-minerals used to resolve the dynamics of a broad range of processes, from diagenetic to magmatic conditions Finally, a brief section at the end outlines a few of the current challenges and promising perspectives for future work
To introduce the four REE-minerals in style, let us recall the origins of their names The three phosphates have well respected Greek grandparents, and allanite has solid Scottish roots, yet of all four of them show idiosyncracies in etymology or type material
Apatite had long puzzled naturalists, as it shows great chemical and physical variability and can resemble other minerals Once properly identified, Abraham Gottlieb Werner named it apatite His reasoning referred to the Greek root ἀπατὰω and giving the precise Latin translation: decipio Taken literally, both mean “I deceive” or “I mislead”, which sounds like an apt confession from this mineral for having fooled …
121 citations