Tectonics
Geologically, the Cenozoic is the era when the continents moved into their current positions. Australia-New Guinea, having split from Gondwana during the early Cretaceous, drifted north and, eventually, collided with South-east Asia; Antarctica moved into its current position over the South Pole; the Atlantic Ocean widened and, later in the era, South America became attached to North America.
India collided with Asia 55 to 45 million years ago; Arabia collided with Eurasia, closing the Tethys ocean, around 35 million years ago.
Read more about this topic: Cenozoic