| Stratigraphic Name | Age | Lithology | Occurrence Records |
|---|
| Akima | 66.0 - 2.59 Ma
Cenozoic | siltstone | 10 |
| Itahana | 11.6 - 5.33 Ma
Miocene | conglomerate/tuff, sandstone | 89 |
| Yoshii | 23.0 - 5.33 Ma
Miocene | sandstone/siltstone | 26 |
| Izumi - Hiketa | 83.5 - 70.6 Ma
Late/Upper Cretaceous | | 1 |
| Izumi - Kita-Ama | 70.6 - 66.0 Ma
Late/Upper Cretaceous | | 4 |
| Izumi - Kokawa | 72.1 - 66.0 Ma
Late/Upper Cretaceous | | 1 |
| Izumi - Matsuo | 83.6 - 66.0 Ma
Late/Upper Cretaceous | siliciclastic | 1 |
| Izumi - Minato, Azenotani & Shichi Shale, Kitaama Sandstone, Yoroizaki Sandstone | 83.6 - 72.1 Ma
Late/Upper Cretaceous | shale/sandstone | 16 |
| Izumi - Minato, Azenotani, Kitaama & Shichi Shale, Shimonada Siltsone, Yoroizaki Sandstone | 83.6 - 72.1 Ma
Late/Upper Cretaceous | shale/sandstone | 26 |
| Izumi - Mutsuo | 72.1 - 66.0 Ma
Late/Upper Cretaceous | | 2 |
| Izumi - Mutsuo - Azenotani Mudstone | 70.6 - 66.0 Ma
Late/Upper Cretaceous | | 2 |
| Izumi - Nakato Shale | 83.5 - 70.6 Ma
Late/Upper Cretaceous | mudstone | 1 |
| Izumi - Seidan | 83.5 - 70.6 Ma
Late/Upper Cretaceous | | 1 |
| Izumi - Shimonada | 70.6 - 66.0 Ma
Late/Upper Cretaceous | siliciclastic | 3 |
| Izumi - Shimonada siltstone & Kitaama Sandstone | 72.1 - 66.0 Ma
Late/Upper Cretaceous | siltstone/sandstone | 6 |
| Izumi - Shimonada Siltstone and Sandstone & Kitaama Sandstone and Shale | 72.1 - 66.0 Ma
Late/Upper Cretaceous | siltstone/"shale" | 18 |
| Izumi - Shindachi | 72.1 - 66.0 Ma
Late/Upper Cretaceous | siliciclastic | 1 |
| Izumi - Shintachi | 72.1 - 66.0 Ma
Late/Upper Cretaceous | | 1 |
| Izumi - Tsubasayama Sandstone | 83.6 - 72.1 Ma
Late/Upper Cretaceous | sandstone/"shale" | 1 |
| Osaka - Atago | 2.59 - 0.78 Ma
Pleistocene | | 1 |
| Tetori - Kitadani | 129 - 101 Ma
Early/Lower Cretaceous | sandstone/"shale", sandstone, siltstone | 37 |
| Hayami I. (1975) A systematic survey of the Mesozoic Bivalvia from Japan, The University Museum, The University of Tokyo, Bulletin 10 |
| Furuichi M. (1982) A new nautiloid species from the Upper Cretaceous Izumi Group of Shikoku, Transactions and Proceedings of the Paleontological Society of Japan, N.S. 126, 334-340 |
| Collins H., Kanie Y., et al (1993) Late Cretaceous crabs from Japan, Transactions and Proceedings of the Paleontological Society of Japan, N.S. 172, 292-310 |
| Yabumoto Y., Uyeno T. (1994) Late Mesozoic and Cenozoic fish faunas of Japan, The Island Arc 3, 255-269 |
| Suzuki D., Saegusa H., et al (2005) Newly found hadrosaurid fossil co-producing broadleaf fossils from Sumoto, west central Japan, Journal of Vertebrate Paleontology 25 3, suppl., 120A |
| Tanimoto M. (2005) Mosasaur remains from the Upper Cretaceous Izumi Group of southwest Japan, Netherlands Journal of Geosciences — Geologie en Mijnbouw 84 3, 373-378 |
| Konishi T., Tanimoto M., et al (2012) A large mosasaurine (Squamata: Mosasauridae) from the latest Cretaceous of Osaka Prefecture (SW Japan), Paleontological Research 16 2, 79-87 doi:10.2517/1342-8144-16.2.079 |
