Where: Wabasha County, Minnesota (44.4° N, 92.3° W: paleocoordinates 19.7° S, 80.1° W)
• coordinate based on nearby landmark
• outcrop-level geographic resolution
When: Tomah Member (Franconia Formation), Franconian (497.0 - 485.4 Ma)
• LITHOSTRATIGRAPHY: Tomah Mbr of the Franconia Fm (following Ber 1953, 1954). STRATIGRAPHIC RELATIONS: From the Tomah Mbr, the middle member of the Franconia Fm, which is overlain by the Reno Mbr. The Franconia Fm is overlain by the Black Earth Mbr of the St Lawrence Fm. AGE: From the Ptychaspis granulosa zonule, Ptychaspis-Prosaukia Zone (Howell et al. 1944) of the Middle Croixan. STRATIGRAPHIC POSITION: Unit 8, 1 ft thick, in the lower portion of a 65+ ft thick section.
• bed-level stratigraphic resolution
Environment/lithology: offshore; lithified, fine-grained, micaceous sandstone
Size class: macrofossils
Preservation: cast, mold/impression
Reposited in the USNM
Collection methods: bulk, quarrying,
• COLLECTOR: R.E Grant. REPOSITORY: USNM
Primary reference: R. E. Grant. 1962. Trilobite distribution, upper Franconia Formation (Upper Cambrian), southeastern Minnestoa. Journal of Paleontology 36(5):965-998 [A. Miller/A. Hendy]more details
Purpose of describing collection: taxonomic analysis
PaleoDB collection 62105: authorized by Austin Hendy, entered by Austin Hendy on 12.07.2006
Creative Commons license: CC BY (attribution)
Taxonomic list
Trilobita | |
Idahoia wisconsensis Hall 1863 trilobite
Idahoia serapio Walcott 1924 trilobite | |
Ptychaspis granulosa Owen 1852 trilobite | |
Stigmacephalus flexifrons Feniak 1952 trilobite |