The scale of how large the vents are.
7. The National Science Foundation Soon Began Funding Explorations Of The Lost City
In 2003, three years after the initial discovery of the Lost City, the National Science Foundation took an interest in exploring them further. Scientists from the NSF used the submersible Alvin to make a 32-day voyage specifically for creating a bathymetric map of the hydrothermal vents.
A bathymetric map is similar to a topographic map; they both show differences in elevation across a specified area. The creation of the bathymetric map of the Lost City helped to pave the way for future explorations because the scientists would know the depths that they needed to plan for.