[Rockhounds] More than 19,000 undersea volcanoes discovered

[Kreigh Tomaszewski]

The U.S. submarine fleet’s biggest adversary lately hasn’t been Red
October. 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.

With only one-quarter of the sea floor mapped with sonar, it is impossible
to know how many seamounts exist. But radar satellites that measure ocean
height can also find them, by looking for subtle signs of seawater mounding
above a hidden seamount, tugged by its gravity. A 2011 census using the
method found more than 24,000. High-resolution radar data have now added
more than 19,000 new ones. The vast majority—more than 27,000—remain
uncharted by sonar. “It’s just mind boggling,” says David Sandwell, a
marine geophysicist at the Scripps Institution of Oceanography, who helped
lead the work.

https://www.science.org/content/article/it-s-just-mind-boggling-more-19-000-undersea-volcanoes-discovered