The physical growth of Orlando, Florida, especially to the east and south, is apparent in these images. Builders in the area have to plan construction carefully because this land is karstic. Karst terrain is characterized by springs, caves, sinkholes, and a unique hydrogeology that results in aquifers that are highly productive but extremely vulnerable to contamination.
The term karstic comes from Karst, a region in the Balkans whose underlying rock is limestone, which slowly dissolves in the groundwater giving it a distinctive terrain and water cycle. Karstic lands comprise 5 to 10 percent of the Earth's land surface, where oceans have retreated as they did in Florida. Millions of years ago, Florida was under water; calcium crystals and seashells sank to this ocean floor and gradually compacted into hard limestone. As the ocean dropped, Florida became covered by plants and soil, and subject to rainwater.
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