New Uranium-lead (U-Pb) Zircon Geochronology of Sholayar Alkaline Syenite Complex, Kerala

Author(s)
Moumita Chowdhury, Jyotisankar Ray, J. K. Tomson, Debaleena Sarkar, Suresh C. Patel, Rajeev Kumar, Pratik Mukherjee, Soumili Sahoo, Christian Koeberl
Abstract

U-Pb age data from the leuco-syenite from the Sholayar Alkaline Syenite Complex (SASC) (10°17’59.9"N: 076°47’26.3"E) is presented in this study. The present sample contains alkali feldspar (orthoclase), oligoclasic plagioclase, diopsidic pyroxene, biotite and opaque minerals (magnetite and ilmenite). The modal data of constituent minerals is plotted over the IUGS classification diagram and the data plots fall within the syenite field. Obtained age (mean age 706.7 ± 8.4 Ma) largely corresponds to the Cryogenian period. In chondrite-normalized diagrams, the syenite shows some affinity towards well-studied silica over-saturated syenites of the Southern Granulite Terrane (SGT). The Ti-in zircon thermometry indicates the crystallization temperature in the range of 613° to 755°C. The reported zircon U-Pb age suggests evidence for Cryogenian alkaline magmatism in the SGT associated either with asthenospheric upwelling in an extensional setting or subduction related continental rifting.

Organisation(s)
Department of Lithospheric Research
External organisation(s)
University of Calcutta, Amity University Punjab, National Centre for Earth Science Studies, Indian Institute of Technology Bombay, Geological Survey of India
Journal
JOURNAL OF THE GEOLOGICAL SOCIETY OF INDIA
Volume
100
Pages
1311-1319
No. of pages
9
ISSN
0016-7622
DOI
https://doi.org/10.17491/jgsi/2024/173984
Publication date
09-2024
Peer reviewed
Yes
Austrian Fields of Science 2012
105105 Geochemistry
Keywords
ASJC Scopus subject areas
Geology
Portal url
https://ucrisportal.univie.ac.at/en/publications/3a3e53ab-f384-4f5f-8289-dc3bea8a19f7