I just thought I'd edit this page because the Razor Reef deserves more credit.
The Razor Reef is an everlasting storm that surrounds the Island of Dinotopia. While Island hopping, Karl, David and Frank fly into the razor reef. The boys wash up on the shores of Dinotopia, while their father swims to the diamond cave.
In the episode 'Temptation', Karl finds a radio and makes contact with a group of survivors heading towards the reef. He manages to direct a navy ship to rescue them. He has the option to leave dinotopia by telling them his coordinates, but he chooses to stay.
The Razor Reef appears to be some mysterious force of nature. It isn't just a storm, as it never deteriorates, and what's more, the Scott's plane seemed to almost power down on its own, meaning that the reef may disable electrical systems.
Although not canon, in 'Dinotopia: Quest for the Ruby Sunstone', Albagon states that the sunstones create a barrier between dinotopia and the outside world. This could suggest that the magic of the sunstones is what keeps the razor reef going.