Where: Japan (35.7° N, 140.9° E: paleocoordinates 36.2° N, 140.3° E)
• coordinate based on nearby landmark
• outcrop-level geographic resolution
When: Naarai Formation, Piacenzian (3.6 - 2.6 Ma)
• From the "Brachiopod-Crevices" which are cut into the Paleozoic rocks. The Inubo Group (of which the Naarai Fm is the basal part) on the Choshi peninsula is composed of marine deposits with a thickness of about 500 m. The depositional age of the group has been estimated at 3.2 Ma to 0.4 Ma from nannofossil biostratigraphy (Nishida 1980; Fujioka & Kameo 2004), magnetostratigraphy (Niitsuma 1970; Sakai 1990), and widespread tephras (Fujioka & Kameo 2004; Tamura et al. 2006). Over 50 tephra beds are intercalated in this group (Sakai 1990; Fujioka & Kameo 2004). Naarai Fm spans the Plio-Pleistocene boundary (ranging from Piacenzian to Gelasian) (Satoguchi & Nagahashi 2012), but this locality is from the lower part.
• group of beds-level stratigraphic resolution
Environment/lithology: marine; poorly lithified, tuffaceous, blue sandstone
Size class: macrofossils
Primary reference: K. M. Hatai. 1940. The Cenozoic Brachiopoda of Japan. Science Reports, Tohoku Imperial University, Series 2 20:1-413 [M. Clapham/M. Clapham]more details
Purpose of describing collection: taxonomic analysis
PaleoDB collection 190821: authorized by Matthew Clapham, entered by Matthew Clapham on 18.12.2017
Creative Commons license: CC BY (attribution)
Taxonomic list
Rhynchonellata | |
Gryphus radiata Hatai 1936
Gryphus angularis Hayasaka 1922 | |
Terebratulina simosensis Hatai 1940 | |
Dallina simosensis Hatai 1940 | |
Laqueus quadratus Yabe and Hatai 1934
Laqueus kosibensis Hatai 1936 |