…Hillier, J. K., and A. B. Watts (2007)

By Jo Nova

What would we know?

Underwater seamounts are one to four kilometer high mountains that mostly used to be a volcano. But under a kilometer of water they are hard to see, holy smoke, and we know more about the moon than the bottom of the Mariana, and it’s only 11km “away”.

Most of these undersea volcanoes remain uncharted by sonar, and with only one-quarter of the sea floor mapped, it is impossible to know how many exist. Sometimes we only find out when a nuclear submarine runs into one:

“It’s just mind boggling.” More than 19,000 undersea volcanoes discovered

New seamount maps could aid in studies of ecology, plate tectonics, and ocean mixing

Paul Voosen, Science

In 2005, the nuclear-powered USS San Francisco collided with an underwater volcano, or seamount, at top speed, killing a crew member and injuring most aboard. It happened again in 2021 when the USS Connecticut struck a seamount in the South China Sea, damaging its sonar array.

Despite discovering nearly half the known underwater volcanoes just this week, we already knew 30 years ago that they […]