The three stages of coral development illustrated by section drawings of the same island. As the island subsides, the fringing reef builds up into a barrier reef and then becomes an atoll as the land itself sinks below sea level. Darwin and the Beagle by Alan Moorhead, page 237.
The three stages of coral development illustrated by section drawings of the same island. As the island subsides, the fringing reef builds up into a barrier reef and then becomes an atoll as the land itself sinks below sea level. Darwin and the Beagle by Alan Moorhead, page 237.