naa a22 4500 51075676X CHVBK 20180411083125.0 cr unu---uuuuu 180411e20131101xx s 000 0 eng 10.1007/s12594-013-0177-5 doi (NATIONALLICENCE)springer-10.1007/s12594-013-0177-5 Occurrence of paragonite in the hydrothermalwall rock alteration zone of G. R. Halli gold deposit, Chitradurga Schist Belt, Western Dharwar Craton, Southern India [Elektronische Daten] [Susmita Gupta, Fareeduddin,] Paragonite (NaAl2Si3AlO10(OH)2), a dioctahedral sodium mica, occurs as a minor phase in the wall rock alteration assemblage of the Guddadarangavanahalli (G. R. Halli) gold deposit of Western Dharwar Craton, Karnataka. It occurs as colourless to pale yellowish grains and scaly aggregates in chlorite, ankerite and quartz rich matrix of the altered metabasalt. Its presence is noticed in the distal to near proximal wall rock alteration zone, mainly in the southern part of the G. R. Halli gold deposit. Presence of paragonite is identified by X-Ray Diffraction (XRD) and Electron Probe Micro-Analyzer (EPMA) studies. The Na2O content of the paragonite varies between 5.96 wt% and 7.8 wt% whereas K2O ranges from 0.44-2.68 wt%. Al2O3 is measured between 37.73 wt% and 39.72 wt% whereas SiO2 varies from 45.06-47.19 wt%. The relative proportion of Na and K in paragonite varies between Na96K4 and Na77K23. The occurrence of paragonite in the wall rock alteration halo of the G. R. Halli gold deposit is proposed as a result of hydrolysis of metamorphosed plagioclase feldspars during the interaction of the hydrothermal fluids and the wall rock. Geological Society of India, 2013 Paragonite nationallicence Gold mineralization nationallicence Wall rock alteration nationallicence Archaean nationallicence Dharwar craton nationallicence G. R. Halli nationallicence Karnataka nationallicence Gupta Susmita Geological Survey of India (GSI), NER, 781 005, Guwahati, India aut Fareeduddin, GSI, PPOD Division, Kumaraswamy Layout, 560 078, Bangalore, India aut Journal of the Geological Society of India Springer India 82/5(2013-11-01), 461-473 0016-7622 82:5<461 2013 82 12594 https://doi.org/10.1007/s12594-013-0177-5 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s12594-013-0177-5 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Gupta Susmita Geological Survey of India (GSI), NER, 781 005, Guwahati, India aut NATIONALLICENCE 700 1- Fareeduddin GSI, PPOD Division, Kumaraswamy Layout, 560 078, Bangalore, India aut NATIONALLICENCE 773 0- Journal of the Geological Society of India Springer India 82/5(2013-11-01), 461-473 0016-7622 82:5<461 2013 82 12594 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer