Contemporaneous heterotopic facies in the crevasse channel deposits of the Mizusijinjya-higashi archaeological site in Joyo City, Kyoto

Abstract

Results of observation on the flood crevasse channel deposits at the Mizusijinjya-higashi archaeological site in Joyo City, Kyoto, Japan, we found the followings that the sand layer of channel sediments and the mud layer of floodplain sediments form a set of contemporaneous heterotopic relatioship with a thickness of several tens of centimeters, and the units overlap to form an aggregate of valley-shaped channel deposits. That is, one contemporaneous heterotopic unit was deposited during one flood period of a few hours to a few days, and the unit was also formed by reflecting the difference in concentratio of the substance in flow. It is difficult to identify lithological boundaries in such deposits, and their traces are prone to error.