sentences:  In March 1913, a fossil tooth from a Parastegodon (similar to the Stegodon genus) was found in what is now Yurigaoka 2-19 in the upper sedimentary layers of mudstone.It is thought to have been from the late Pliocene period.Most of what is now the city of Kawasaki was under water during this period, so the fossil indicates that the Asao area was above water and perhaps marked the shoreline.