EPMA monazite geochronology of the basement and supracrustal rocks within the Pur-Banera basin, Rajasthan: Evidence of Columbia breakup in Northwestern India

• Mangalwar complex (MC) underwent a mid-amphibolite peak metamorphism at ∼1.82 Ga.
• MC and Pur-Banera (PB) witnessed upper amphibolite peak metamorphism at 1.37–1.35 Ga.
• Grenvillian high pressure overprinting in both MC and PB rocks at 1.05–0.99 Ga.
• Episodic garnet growth for a period of ∼0.84 Ga in the MC.
• Evidence of Columbia and Rodinia supercontinent cycles.

We deduce the timing of the rift-induced collisional event between two orogenies in the central Aravalli–Delhi Fold Belt using monazite chemical dating and metamorphic P–T estimates from metapelites of the Mangalwar Complex (MC), and the overlying Pur-Banera (PB) supracrustals. The MC rocks preserve evidence of three regional metamorphic events, while the PB rocks record the last event. The M1 metamorphism attained its peak P–T at ∼5.5 kbar and 520–550 °C in the MC rocks at ∼1.82 Ga, followed by the M2 event with peak P–T of ∼7.5 kbar and 580–660 °C at ∼1.35 Ga. The youngest high-pressure M3 metamorphism attained a peak P–T of ∼8.0 kbar and 590–640 °C at ∼0.99 Ga. Thermobarometry coupled with ages of included monazites in chemically zoned garnet from the MC metapelites indicate preservation of ages spanning between ∼1.82 Ga and ∼0.99 Ga from different zones (i.e., core to rim), implying episodic garnet growth during supercontinent cycle. The PB metapelites constitute two prominent ages of ∼1.37 Ga and ∼1.05 Ga. The youngest high-pressure metamorphism (M3) in the PB rocks with maximum P–T of ∼8.0 kbar, and 580–670 °C during the Neoproterozoic has overprinted their earlier metamorphic records. Based on monazite geochronology, we assign the ∼1.82 Ga and ∼1.37–1.35 Ga ages to the amalgamation and breakup of the Columbia supercontinent respectively. The youngest age record of ∼1.05–0.99 Ga indicates evidence of Rodinia formation in and around the Pur-Banera basin.