Dolphins determine their surroundings by listening to echoes. Can they mimic those echoes and communicate it to other dolphins, transmitting an "image"? Does the same go for all echolocators?
As I understand your question, dolphins (and other echolators) can more or less map out their "surroundings" (which might include nearby ice floes, for example). It sounds like you're asking if they can then transmit that knowledge to other members of their species.
I don't know the answer, and I suspect no one does. However, it's hard to imagine why one dolphin would need to tell another dolphin about its surroundings when the second dolphin ought to be able to map its surroundings all by itself.
Cetaceans do communicate with each other, presumably alerting each other to danger (e.g. predators) and the presence of prey.
Incidentally, I worked on an acoustic study of bowhead whales in the Arctic Ocean years ago. We recorded bowheads and Arctic seals, which make some unbelievable sounds. We operated under the presumption that they were primarily "sounding out" their environment - searching for open areas in the ice where they could breathe, for example. It's possible that one whale might say "Hey, I found a breathing hole!" without mimicking the echoes that alerted it to that hole.
Sorry, that's not really a direct answer, but it might help put things in perspective.