Dear Francesco,

You may obtain some crude chronological estimate by trying the following:

A) Select the robust taxa and observe their taphonomic state (abrasion, disarticulation, fragmentation, secondary rounding, etc.).

B) Note the annual input rate (seasonally variable) of the chosen taxa and the rate of taphonomic changes with time.

C) Use data from steps A and B to infer the antiquity (very rough estimate only) of the rehash assemblage.

Best wishes