It’s part of a long-term effort, funded by governments and nonprofits around the world, to map the entire seafloor for the first time. And it’s got major global economic implications.

The group Nautilus Live recently returned from a 21-day expedition surveying and mapping the ocean floor around the Solomon ...

In the 1950s, geologist Marie Tharp turned depth measurements into detailed maps of the ocean floor. It led to her discovery of the Mid-Atlantic rift.

In the past, scientists relied on sonar-equipped ships to map underwater terrain, but this method was slow and expensive. With just 25% of the ocean floor mapped this way, a full picture was far ...