Blue Holes, Underwater Time Capsules Blue holes contain many mysteries underwater that go unknown, and the Documentary “Extreme Cave Diving” try tp unlock the mysteries. The Bahamas has many blue hole and they were made during the Ice Age when the ocean levels lowered and rain carved out the limestone in the Bahamas, thus as the sea level ascended the caves filled with ocean water at the bottom and fresh water on top. An important part of blue holes is that toward the deeper points they lack oxygen, making it a time capsule since bones at this depth won’t decay. Today the bahamas are free of big predators but finding in the blue hole show proof of crocodiles, tortoises, and many other animals that are either extinct or no longer living on
