Middle Haborogawa Fm - Sample DF0067, Detofutamata River (Cretaceous of Japan)

Where: Japan (44.1° N, 141.8° E: paleocoordinates 50.4° N, 132.1° E)

• coordinate estimated from map

• outcrop-level geographic resolution

When: Middle Haborogawa Formation (Yezo Group), Santonian (86.3 - 83.6 Ma)

• STRATIGRAPHIC RELATIONS: Unit Uf-g, Middle Haborogawa Fm overlain by Upper Haborogawa Fm of the Yezo Gp and the Campanian-Maastrichtian Pankezawa Fm. THICKNESS: 450 m. AGE: Santonian, Inoceramus amakusensis zone. STRATIGRAPHIC POSITION: At middle of section, at top of 250 m thick Middle Haborogawa Fm. Correlates closely to PBDB 62332 (DF0065) and 62334 (DF0069), ~20 m above PBDB 62331 (DF0079).

• group of beds-level stratigraphic resolution

Environment/lithology: offshore; lithified, bioturbated, sandy mudstone

• ENVIRONMENT: No environmental data reported. Assigned to Siliciclastic - offshore on the basis of facies description. TECTONIC SETTING: No tectonic data reported. SEQUENCE STRATIGRAPHY: No sequence stratigraphic data reported, assumed to be regressive as in coarsening up portion of sedimentary sequence.
• SPECIFIC LITHOLOGY: Bioturbated sandy mudstone. LITHIFICATION: Unknown lithification, assumed to be lithified.

Size class: macrofossils

Collection methods: COLLECTOR: Assumed to be collected by authors (Moriya and Hirano) and supplemented by collections of an earlier author Toshimitsu (see Toshimitsu 1988). REPOSITORY: Unknown repository, posibly Waseda University, Japan.

Primary reference: K. Moriya and H. Hirano. 2001. Cretaceous stratigraphy in the Chikubetsu area, Hokaido. Journal of the Geological Society of Japan 107(3):199-214 [A. Miller/A. Hendy/A. Hendy]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 62333: authorized by Austin Hendy, entered by Austin Hendy on 18.07.2006

Creative Commons license: CC BY (attribution)

Taxonomic list

• COMPLETENESS: Fairly comprehensive for all macrofauna. NOMENCLATURE: Not an authoritative publication, but with modern nomenclature and species-level assignments.
Bivalvia
 Myalinida - Inoceramidae
Inoceramus (Inoceramus) amakusensis Nagao and Matsumoto 1940 clam
Sphenoceramus naumanni Yokoyama 1890 clam
Cephalopoda
 Phylloceratida - Phylloceratidae
 Ammonitida - Baculitidae
Baculites bailyi Woods 1906 ammonite
 Ammonitida - Tetragonitidae
"Gaudryceras denseplicatum" = Gaudryceras (Gaudryceras) denseplicatum Jimbo 1894 ammonite
Gaudryceras tenuiliratum Yabe 1903 ammonite
Tetragonites glabrus Jimbo 1910 ammonite