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Yerrabali schist belt; monazite dating; Eastern Dharwar craton; EPMA chemical dating

The Dharwar craton is divided in to the Western and Eastern Dharwar craton (WDC and EDC) by the N–S trending Chitradurga Shear zone. The EDC mainly consists of late Archean granites interspersed with N–S trending linear schist belts. The Yerrabali Schst belt (YSB) is located at the north-eastern corner of the EDC, near the Karimnagar granulite belt. The YSB is metamorphosed in middle-upper amphibolite facies and consists of Banded Magnetite Quartzite (BMQ), ferruginous quartzite, ultramafics, quartz–cordierite–gedrite $\pm$ garnet bearing quartzite, dolomite, amphibolite, deformed metapyroxenite, tremolite schist, sillimanite–garnet–cordierite schist, and dolerite dykes. We have dated monazites in the sillimanite–garnet–cordierite schist, exposed at the SW part of the YSB by EPMA chemical method. So far no dates are available from the YSB. The monazite chemical ages with three distinct populations, viz., $2658 \pm 42$, $2817 \pm 19$ and $3097 \pm 34 \rm{Ma}$, probably correspond to three distinct metamorphic phases. The peak metamorphism at around 2800 Ma corresponds with the garnet and cordierite growth. A temperature of $673^{0}\rm{C}$ and a pressure of 4.7 kb have been estimated for peak metamorphism.

SANKHA DAS¹ SANDIP NANDY² G RAMACHANDRAN³ SHAMPA KHAN²

1. National Mission-IA, Geological Survey of India, Kolkata, India.
2. EPMA Laboratory, Geological Survey of India, Kolkata, India.
3. State Unit Telangana, Geological Survey of India, Hyderabad, India.

Published

20 February 2020

Manuscript received

2 February 2019

Manuscript revised

2 October 2019

Accepted

5 November 2019

Early published

Unedited version published online

Final version published online

15 February 2020