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Chakrabarti, Ramananda
- Silicon Isotopes: From Cosmos to Benthos
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PDF Views:80
Authors
Affiliations
1 Centre for Earth Sciences, Indian Institute of Science, Bengaluru 560 012, IN
1 Centre for Earth Sciences, Indian Institute of Science, Bengaluru 560 012, IN
Source
Current Science, Vol 108, No 2 (2015), Pagination: 246-254Abstract
Silicon is the second most abundant element on the Earth and one of the more abundant elements in our Solar System. Variations in the relative abundance of the stable isotopes of Si (Si isotope fractionation) in different natural reservoirs, both terrestrial (surface and deep Earth) as well as extra-terrestrial (e.g. meteorites, lunar samples), are a powerful tracer of present and past processes involving abiotic as well as biotic systems. The versatility of the Si isotope tracer is reflected in its wide-ranging applications from understanding the origin of early Solar System objects, planetary differentiation, Moon formation, mantle melting and magma differentiation on the Earth, ancient sea-water composition, to modern-day weathering, clay formation and biological fractionation on land as well as in the oceans. The application of Si isotopes as tracers of natural processes started over six decades ago and its usage has seen a sudden increase over the last decade due to improvements in mass spectrometry, particularly the advent of multicollector inductively coupled plasma mass spectrometers, which has made Si isotope measurements safe and relatively easy while simultaneously improving the accuracy and precision of measurements.Keywords
Mass Spectrometry, Meteorites, Sea Water, Silicon Isotopes, Weathering.Full Text
- Mesoproterozoic 40Ar/39Ar Age and Sr–Nd Isotopic Geochemistry of Calc-alkaline Lamprophyre fromthe Mudigubba Area, Eastern Dharwar Craton, India
Abstract Views :202 |
PDF Views:86
Authors
Affiliations
1 Department of Geology, Institute of Science, Banaras Hindu University, Varanasi 221 005, IN
2 Centre for Earth Sciences, Indian Institute of Science, Bengaluru 560 012, IN
1 Department of Geology, Institute of Science, Banaras Hindu University, Varanasi 221 005, IN
2 Centre for Earth Sciences, Indian Institute of Science, Bengaluru 560 012, IN
Source
Current Science, Vol 119, No 7 (2020), Pagination: 1142-1148Abstract
We report a 40Ar/39Ar Mesoproterozoic radiometric age for a calc-alkaline lamprophyre dyke from the Mudigubba area towards the western margin of the Cuddapah Basin, Eastern Dharwar Craton (EDC), Southern India. Amphibole phenocryst separates from this lamprophyre yielded a plateau age of 1169 ± 8 Ma (2σ ), which is almost 50 million years older than the majority of radiometric dates available for the Wajrakarur field kimberlites which are proximal to this dyke. Bulk-rock Sr–Nd isotopic analyses of the Mudigubba lamprophyre dykes (εNd(t) between –13.3 and –12.4) reveal their derivation from an old, enriched, continental lithospheric mantle unlike the kimberlites (bulk-rock and perovskite in situ εNd(t)) between –0.77 and +7.93), which originated either from a chondritic or depleted mantle source. This study provides further evidence for emplacement of compositionally distinct, mantle-derived Mesoproterozoic alkaline magmas in the EDC and highlights the extremely heterogeneous character of the lithospheric mantle beneath this craton.Keywords
Alkaline Magma, Lamprophyre Dyke, Lithospheric Mantle, Kimberlites, Radiometric Age.Full Text
References
- Chalapathi Rao, N. V., Wu, F.-Y., Mitchell, R.H., Li, Q.-L. and Lehmann, B., Mesoproterozoic U–Pb ages, trace element and Sr–Nd isotopic composition of perovskite from kimberlites of the Eastern Dharwar Craton, southern India: distinct mantle sources and a widespread 1.1 Ga tectonomagmatic event. Chem. Geol., 2013, 353, 48–64.
- Chalapathi Rao, N. V., Giri, R. K., Sharma, A. and Pandey, A., Lamprophyres from the Indian shield: a review of their occurrence, petrology, tectonomagmatic significance and relationship with the Kimberlites and related rocks. Episodes, 2020, 43(1), 231–248.
- Smith, C. B., Haggerty, S. E., Chatterjee, B., Beard, A. and Townend, R., Kimberlite, lamproite, ultramafic lamprophyre, and carbonatite relationships on the Dharwar Craton, India; an example from the Khaderpet pipe, a diamondiferous ultramafic with associated carbonatite intrusion. Lithos, 2013, 182–183, 102–113.
- Devaraju, T. C., Laajoki, K., Zozulya, D., Khanadali, S. D. and Ugarkar, A. G., Neo–proterozoic dyke swarms of southern Karnataka: Part II: geochemistry, oxygen isotope composition, Rb–Sr age and petrogenesis. Mem. Geol. Soc. India, 1995, 33, 267–306.
- Pandey, A. and Chalapathi Rao, N. V., Supercontinent transition as a trigger for ∼1.1 Gyr diamondiferous kimberlites and related magmatism in India. Lithos, 2020, 370–371, 105620.
- Kumar, A., Heaman, L. M. and Manikyamba, C., Mesoproterozoic kimberlites in south India: a possible link to ~1.1 Ga global magmatism. Precambrian Res., 2007, 154, 192–204.
- Chalapathi Rao, N. V., Creaser, R. A., Lehmann, B. and Panwar, B. K., Re–Os isotopic study of Indian kimberlites and lamproites: implications for mantle source regions and cratonic evolution. Chem. Geol., 2013, 353, 36–47.
- Paton, C., Hergt, J. M., Phillips, D., Woodhead, J. D. and Shee, S. R., New insights into the genesis of Indian kimberlites from the Dharwar Craton via in situ Sr isotope analysis of groundmass perovskite. Geology, 2007, 35, 1011–1014.
- Paton, C., Hergt, J. M., Woodhead, J. D., Phillips, D. and Shee, S. R., Identifying the asthenospheric component of kimberlite magmas from the Dharwar Craton, India. Lithos, 2009, 112S, 296–310.
- Pandey, A., Chalapathi Rao, N. V., Chakrabarti, R., Pandit, D., Pankaj, P., Kumar, A. and Sahoo, S., Petrogenesis of a Mesoproterozoic shoshonitic lamprophyre dyke from the Wajrakarur kimberlite field, eastern Dharwar Craton, southern India: geochemical and Sr–Nd isotopic evidence for a modified sub-continental lithospheric mantle source. Lithos, 2017, 292–293, 218–233.
- Khan, S., Dongre, A., Vilijoen, F., Li, Q.-L. and Le Roux, P., Petrogenesis of lamprophyres synchronous to kimberlites from the Wajrakarur kimberlite field: implications for contrasting lithospheric mantle sources and geodynamic evolution of the eastern Dharwar Craton of southern India. Geol. J., 2019, 54(5), 2994– 3016.
- Raghuvanshi, S., Pandey, A., Pankaj, P., Chalapathi Rao, N. V., Chakrabarti, R., Pandit, D. and Pandey, R., Lithosphere– asthenosphere interaction and carbonatite metasomatism in the genesis of Mesoproterozoic shoshonitic lamprophyres at Korakkodu, Wajrakarur kimberlite field, Eastern Dharwar Craton, southern India. Geol. J., 2019, 54(5), 3060–3077.
- Pankaj, P., Giri, R. K., Chalapathi Rao, N. V., Chakrabarti, R. and Raghuvanshi, S., Mineralogy and petrology of shoshonitic lamprophyre dykes from the Sivarampeta area, diamondiferous Wajrakarur Kimberlite Field, Eastern Dharwar Craton, southern India. J. Mineral. Petrol. Sci., 2020, https://doi.org/10.2465/ jmps.191004b.
- Pandey, A., Chalapathi Rao, N. V., Pandit, D., Pankaj, P., Pandey, R., Sahoo, S. and Kumar, A., Subduction-tectonics in the evolution of the eastern Dharwar Craton, southern India: insights from the post-collisional calc-alkaline lamprophyres at the western margin of the Cuddapah Basin. Precambrian Res., 2017, 298, 235–251.
- Pandey, A., Chalapathi Rao, N. V., Chakrabarti, R., Pankaj, P., Pandit, D., Pandey, R. and Sahoo, S., Post-collisional calc-alkaline lamprophyres from the Kadiri greenstone belt: evidence for the Neoarchean convergence-related evolution of the Eastern Dharwar Craton and its schist belts. Lithos, 2018, 320–321, 105– 117.
- Renne, P. R., Swisher, C. C., Deino, A. L., Karner, D. B., Owens, T. L. and DePaolo, D. J., Intercalibration of standards, absolute ages and uncertainties in 40Ar/39Ar dating. Chem. Geol., 1998, 145, 117–152.
- Banerjee, A., Chakrabarti, R. and Mandal, S., Geochemical anatomy of a spheroidally weathered diabase. Chem. Geol., 2016, 440, 124–138.
- Heaman, L. M., Phillips, D. and Pearson, G., Dating kimberlites: methods and emplacement patterns through time. Elements, 2019, 15(6), 399–404.
- Chalapathi Rao, N. V., Gibson, S. A., Pyle, D. M. and Dickin, A. P., Contrasting isotopic mantle sources for Proterozoic lamproites and kimberlites from the Cuddapah Basin and Eastern Dharwar Craton: implication for Proterozoic mantle heterogeneity beneath southern India. J. Geol. Soc. India, 1998, 52(6), 683–694.
- Chakrabarti, R., Basu, A. R. and Paul, D. K., Nd–Hf–Sr–Pb isotopes and trace element geochemistry of Proterozoic lamproites from southern India: subducted komatiite in the source. Chem. Geol., 2007, 236, 291–302.
- Talukdar, D., Pandey, A., Chalapathi Rao, N. V., Kumar, A., Pandit, D., Belyatsky, B. and Lehmann, B., Petrology and geochemistry of the Mesoproterozoic Vattikod lamproites, Eastern Dharwar Craton, southern India: evidence for multiple enrichment of sub-continental lithospheric mantle and links with amalgamation and break-up of the Columbia supercontinent. Contrib. Mineral. Petrol., 2018, 173, 67.
- McCulloch, M. T., Jaques, A. L., Nelson, D. R. and Lewis, J. D., Nd and Sr isotopes in kimberlites and lamproites from Western Australia: an enriched mantle origin. Nature, 1983, 302, 400–403.
- Chalapathi Rao, N. V. et al., Petrology, 40Ar/39Ar age, Sr–Nd isotope systematic, and geodynamic significance of an ultrapotassic (lamproitic) dyke with affinities to kamafugite from the easternmost margin of the Bastar Craton, India. Mineral. Petrol., 2016, 110, 269–293.
- Tappe, S., Romer, R. L., Stracke, A., Steenfelt, A., Smart, K. A., Muehlenbachs, K. and Torsvik, T. H., Sources and mobility of carbonate melts beneath cratons, with implications for deep carbon cycling, metasomatism and rift initiation. Earth Planet. Sci. Lett., 2017, 466, 152–167.
- Naqvi, S. M., Geology and Evolution of the Indian Plate (from Hadean to Holocene – 4 Ga to 4 Ka), Capital Publishing Company, New Delhi, 2005, p. 450.
- Jacobsen, S. B. and Wasserburg, G. J., Sm–Nd isotopic evolution of chondrites. Earth Planet. Sci. Lett., 1980, 50, 139–155.
- Becker, M. and Le Roex, A. P., Geochemistry of South African on- and off-craton, group I and II kimberlites: petrogenesis and source region evolution. J. Petrol., 2006, 47(4), 673–703.
- Chalapathi Rao, N. V., Gibson, S. A., Pyle, D. M. and Dickin, A. P., Petrogenesis of Proterozoic kimberlites and lamproites from the Cuddapah basin and the Dharwar craton, southern India. J. Petrol., 2004, 45, 907–948.
- Sharma, A., Kumar, A., Pankaj, P., Pandit, D., Chakrabarti, R. and Chalapathi Rao, N. V., Petrology and Sr–Nd isotope systematics of the Ahobil kimberlite (pipe-16) from the Wajrakarur field, Eastern Dharwar Craton, southern India. Geosci. Front., 2019, 10(3), 1167–1186.
- Dongre, A., Viljoen, K. S., Belyanin, G., Le Roux, P. and Malandkar, M., Petrogenesis of the diamondiferous pipe-8 ultramafic intrusion from the Wajrakarur kimberlite field of southern India and its relation to the worldwide Mesoproterozoic (∼1.1 Ga) magmatism of kimberlite and related rocks. Geosci. Front., 2019; https://doi.org/10.1016/j.gsf.2019.07.010.