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.
| Originalsprache | Englisch |
|---|---|
| Seiten (von - bis) | 1311-1319 |
| Seitenumfang | 9 |
| Fachzeitschrift | JOURNAL OF THE GEOLOGICAL SOCIETY OF INDIA |
| Jahrgang | 100 |
| Ausgabenummer | 9 |
| DOIs | |
| Publikationsstatus | Veröffentlicht - 1 Sept. 2024 |
Fördermittel
The authors thank the University of Calcutta for providing a field grant (given to JR) to carry out the research work. Sincere thanks are due to the authorities of IIT, Bombay and NCESS, Kerala for providing the necessary laboratory facilities. The authors are grateful to Dr. Sandip Nandy, GSI, Kolkata, for his kind help and guidance during the sample preparation for zircon geochronology. Two anonymous journal reviewers provided incisive and helpful comments to upgrade the quality of the paper.
ÖFOS 2012
- 105105 Geochemie