— The Aryabhatiya of Aryabhata, tr. W. E. Clark (1930)ch1.v3
In short: Aryabhata's cosmological time-scale: a day of Brahman (kalpa) consists of 14 Manus, each Manu containing 72 yugas — a deep-time framework predating modern geological time scales by over a millennium.
Multiple sourcesv2The Aryabhatiya of Aryabhata, tr. W. E. Clark (1930), ch1.v3