The Aravalli Mountains and neighbouring areas have well-preserved records of a protracted history of development of Precambrian basins, which spans about 2500 myr of the Earth’s history. The oldest depositional basins are the greenstone belts that occur within the Archaean gneiss–granite terrain. Geochronological data indicate evolution of one such greenstone belt from 3300 to 2850 Ma. The younger Proterozoic cover successions include the Aravalli Supergroup, Delhi Supergroup and Sirohi Group, which evolved during three successive orogenic cycles spanning between c. 2200 and c. 1850 Ma, c. 1700 and c. 1450 Ma, and c. 1000 and c. 850 Ma, respectively. Each of these lithostratigraphic units evolved in separate basins having distinctive tectonic, metallogenic and evolutionary histories. The inversion of the youngest ‘orogenic’ basin marks the final cratonization of the Precambrian Aravalli crust at around 850 Ma. The succeeding depositional episodes include formation of ephemeral basins during the early phase of the plume-related Malani Group from 780 to 730 Ma, and the formation of the Marwar Supergroup deposited in stable platformal basins marks the terminal phase of the Precambrian crust-building history in the region.
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Precambrian Basins of India: Stratigraphic and Tectonic Context
This Memoir provides a comprehensive review of the Precambrian basins of the four Archaean nuclei of India (Dharwar, Bastar, Singhbhum and Aravalli-Bundelkhand), encompassing descriptions of the time–space distribution of sedimentary–volcanic successions, the interrelationship between tectonics and sedimentation, and basin histories. Studies of 22 basins within the framework of an international basin classification scheme deepen an understanding of the basin architecture especially for cratonic basins. Most Indian sedimentary successions formed as cratonic to extensional-margin rift and thermal-sag basins, some reflecting mantle plume movement, subcrustal heating or far-field stress. This Memoir shows that Phanerozoic plate-tectonic and sequence stratigraphic principles can be applied to the Precambrian basins of large Archaean provinces. The differences between the stratigraphic architecture of the Indian Precambrian and examples of Phanerozoic basin-fill successions elsewhere are ascribed to variable rates and intensities of the controls on accommodation and sediment supply, and changes inherent in the evolution of the hydrosphere–atmosphere and biosphere systems.