How did the movement of the Indian subcontinent help shape the Indian Ocean?

The movement of the Indian subcontinent was a primary driver in the formation and configuration of the Indian Ocean.1

The ocean's development began approximately 180 million years ago with the breakup of the supercontinent Gondwana. The Indian subcontinent, initially attached to Madagascar, separated from Antarctica and Australia around 130 million years ago, a process that opened the central Indian Ocean basin.123

Following this, the subcontinent broke away from Madagascar between 90 and 80 million years ago and began a significant northward drift toward Asia. This movement reorganized the ocean's spreading ridges and continued to shape the basin until the subcontinent collided with Eurasia approximately 50 million years ago. By 36 million years ago, the Indian Ocean had achieved its present-day configuration.31