FORMATION
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Florida’s phosphate deposits are made mostly of ocean animals. They began to form millions of years ago . At that time most of Florida was under water. About 5-10 million years ago, biological and chemical changes changed phosphate from theocean to the phosphate likethat we mine today. This phosphate deposit is huge. It stretches across the Florida. It also streches up to the eastern Atlantic coast all the way to the Chesapeake Bay.
People don't really know how all this phosphate formed, but they have a theory. Many scientists think that this is how it happened. During the geological time called Miocene, ocean water started getting into higher grounds. This is called upwelling. There was a lot of life in the ocean, so the ocean was rich in nutrients and phosphate. This water was now at the seal level. Than water started precipitating, and the sediment full of phosphate was left. Florida's limestone was now full of teeth, bones, and waste of ocean animals.
Many years passed. During the Pleistocene, the ocean levels dropped. Florida's land was out of the ocean now. When Florida's land was out of the water, millions of fossilized bones were found in the pits in which we mine phosphate today. The bones of the pre-historic animals from the Pleistocene can be found in the top phosphate layer. Below that we can find the fossils of ocean animals from the Miocene period. Some animal bones we can find are dugong, mastodons, saber tooth tiger, whales, camels, and three toed hores. No dinasours, though! Florida land got out of the ocean about 25 million years ago - dinasours were extinct 65 million years ago.
This is where rich deposits of Florida phosphate come from. Because of all the remains of ancient animals that are found in phosphate pits the part of central Florida rich in phosphate is nicknamed the Bone Valley.
ANIMALS GEO-TIME
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