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The Florida peninsula is a porous plateau of karst limestone sitting atop bedrock known as the Florida Platform. The emergent portion of the platform was created during the Eocene to Oligocene as the Gulf Trough filled with silts, clays, and sands. Flora and fauna began appearing during the Miocene. No land animals were present in Florida prior to the Miocene. The largest deposits of rock phosphate in the country are found in Florida. Most of this is in Bone Valley. Extended systems of underwater caves, sinkholes and springs are found throughout the state and supply most of the water used by residents. The limestone is topped with sandy soils deposited as ancient beaches over millions of years as global sea levels rose and fell. During the last glacial period, lower sea levels and a drier climate revealed a much wider peninsula, largely savanna. While there are sinkholes in much of the state, modern sinkholes have tended to be in West-Central Florida. ==Early history== During the early Mesozoic Era (251 – 66 mya) the supercontinent of Pangea began to rift and break apart. As North America separated from Africa a small portion of the African plate detached and was carried away with the North American plate. This provided some of the foundation upon which Florida now rests. The emergent portion of the platform was created during the Eocene to Oligocene as the Gulf Trough filled with silts, clays, and sands. Flora and fauna began appearing during the Miocene. No land animals were present in Florida before the Miocene. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Geology of Florida」の詳細全文を読む スポンサード リンク
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