The volcanic Mountain has high topography and cold air that caused the high intensity of rainfall. Trees and grass were spread between rivers’ meander. Early Man population and mammal were developed. That is the depiction of the charm land of Sangiran for more than 500,000 years.
On the period 730,000 – 250,000 years ago, the sea level was relatively normal. There were the increasing of volcanic activities in surrounding Sangiran, resulted in millions of cubic of volcanic material. The rivers transported those volcanic materials and covering grenzbank.
The eruption of volcanic mountains in nearby Sangiran resulted in volcanic dust between thick sediment of Kabuh Formation’s cross-bedding sand. Between that cross-bedding structures were found many early man and their artifacts, and fauna fossils. The domination of cross-bedding sand marks that the Sangiran environment at those time, was a meandered and woven-like rivers environment. (Suwita Nugraha, Wulandari, Iwan SB)
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