Cosmogenic exposure dating the Pre-Columbian archaeological structures at Tiwanaku, Bolivia

Abstract

We use in-situ cosmogenic 10Be in an attempt to date the construction of the Kalasasaya Platform temple at the UNESCO Heritage archaeological site at the ancient city of Tiwanaku, Bolivia. The unique site is located within the altiplano valley of Tiwanaku at 3870 masl near the southern shores of Lake Titicaca. The monuments at Tiwanaku were constructed as ceremonial and civic buildings of exceptional precision and quality by an Andean civilization, who were precursors of the Inca Empire. The date of construction of Tiwanaku is unknown. Earliest settlement is believed to be at least ~3,000 years ago and archeological evidence supports a drought-based empire collapse in the first half of the 12th century.