Anthropogenic origin of siliceous scoria droplets from Pleistocene and Holocene archaeological sites in northern Syria

Abstract

Siliceous scoria droplets, measuring from 1 to 10 mm, from one late Pleistocene and four early Holocene archaeological sites in northern Syria are compared to similar droplets previously suggested to be the result of a cosmic impact at the onset of the Younger Dryas global cooling event. The findings demonstrate that the presence of siliceous scoria droplets are independent of age and thus are not specific to the beginning of the Younger Dryas. Occurrences have not been reported from natural deposits, but are instead associated with buildings destroyed by fire and thus appear to be restricted to archaeological sites. We therefore conclude that melting of building earth in ancient settlements can occur during fires reaching modest temperatures. There is no evidence to suggest that siliceous scoria droplets result from very high temperature melting of soil and are the result of a cosmic event.