| Fossil shark teeth were collected from the Early to th Middle Pleistocene Ichijiku Formation of Kazusa Group in the Ichijyuku area, Kimutsu city, Chiba prefecture, Central Japan. There are many sand quarries in the Ichijyuku area. At these sand quarries, the sand is sifted to a uniform particle size using a water sieve and then shipped for use as construction material.The residue, except for the desired sand, is discarded. Many diverse fossils are produced from small piles made of this waste. |
| Formation |
| Ichijiku Formation: lower Chibanian, 0.78-0.60 Ma Nakayama, N. and Masuda, F. (1987) Ocean current-controlled sedimentary facies of the Pleistocene Ichijiku Formation, Kazusa Group, Boso Peninsula. Jour. Geol. Soc. Japan, 93(11), p.833－845. Nakajima, T. and Watanabe, M. (2005) Geology of the Futtsu District. Quadrangle Series, 1：50,000. Geological Survey of Japan, AIST, 102 pp. |