The Bengal Fan grows
Himalayan erosion builds the largest sediment pile on the planet across the floor of the Indian Ocean.
- When
- —
- Duration
- 12 million years
- Known to
- ± 2 million years
- Era
- Miocene, Cenozoic
Rivers draining the rising Himalaya deliver sediment to the Bay of Bengal on a scale unmatched anywhere: the resulting submarine fan is 3,000 kilometres long and up to 16 kilometres thick. It is a direct archive of mountain erosion, and drilling it gives a continuous record of Himalayan uplift, monsoon strength and vegetation change — including one of the clearest signals anywhere of the late Miocene switch to C4 grasses, recorded in the carbon isotopes of plant waxes washed off the continent.