The form of Earth’s surface is always changing from time to time, but the changing is going so slowly so that we did not recognize until a long process and period. Sangiran we see today has ever been an cean. Fossils such as shells, sharks’ teeth, shell of Sea Turtle, oral, etcetera found in blue clay layer. Kalibeng Formation proved Sangiran had ever been a marine environment at about 2,4 mya. (Harry Widianto dan Iwan Setiawan Bimas)
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