True, but once it evaporates, it can no longer be called seawater. I think you may be reading this in the wrong context. It's a geology story, and geologists s

True, but once it evaporates, it can no longer be called seawater. I think you may be reading this in the wrong context. It's a geology story, and geologists study things that have been buried in the ground a long time. The value is in having a sample of prehistoric seawater to study, as if it were a rock formation.