The Aravalli Mountains extending from Delhi in the north-east to the Gulf of Cambay in the south-west. The besetment of the Aravalli Mountains is comprised of Banded Gneissic Complex of Neoarchean age. It is overlain by three major cycles of deposition followed by orogenic deformation over the period from about 2.2Ga to 0.85 Ga.
- The Aravalli supergroup represents the first cycle of sedimentary fill that is assigned early-middle Paleoproterozoic.
- The secondary cycle begins with the deposition of the rock formation of the Delhi supergroup followed by Delhi Orogeny.
- The third orogenic cycle represented by the rocks of Sirohi Group. that are exposed on the western side of moutains.
They are overlain by cover sequence of Neo-proterozoic age in the west of the Aravalli Mountains. The cove sequences are represented by Malani Volcanics and Marwar supergroup.
The eastern boundary of the Mountains is marked by a tectonic line known as Main Boundary Fault that separates the Bundelkhand Block from the Aravalli Block of the Aravalli Bundelkhand craton. Several isolated bodies of granulite-facies rocks occur within the BGC terrain mainly at sandhmata in the central part of the Aravalli Mountains. They have been collectively named as Sandhmata Complex. They contains two distinct lithoogies : banded gneisses containing bands of amphibole and metasediments and rocks of granulite facies.
The basic granulite is regarded to have been derived from the mantle. A mantle driven melt had underplated the Archaean basement that leads to recrystallization of basement BGC into high T & P Granulite facies. This granulite exhumed along the shear zone.
| Tectonic event | Tectonic setting of basin evolution | Age (Ma) |
| Marwar Supergroup | Stable cratonic basin | 635 to 543 |
| Malani Volcanics | Plume-related underplating and opening of shallow basin | 780 to 680 |
| Erinpura Granite | Anorogenic intrusion | 850 |
| Sirohi Group (west of Aravalli Mountain) | Sirohi Orogenic cycle | 1000 to 825 |
| Delhi Supergroup | Delhi orogenic cycle | 1725 to 1450 |
| Sandmata Complex | Exhumation of granulite | 1725 to 1625 |
| Aravalli Supergroup | Aravalli Orogenic cycle | 2200 to 1850 |
| Archaean basement | Greenstone belt evolution | 3300 to 2500 |
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