Hanxia Formation, Quannaogoushan Area, Near Yumen, Gansu Province (Silurian to of China)

Where: Gansu, China (39.8° N, 97.7° E: paleocoordinates 30.5° S, 101.5° E)

• coordinate based on nearby landmark

• local area-level geographic resolution

When: Hanxia Formation, Ludlow to Ludlow (427.4 - 419.2 Ma)

• Except where otherwise stated, ref. 7624 uses Lower Silurian as equivalent to Llandovery, Middle Silurian as equivalent to Wenlock, and Upper Silurian as equivalent to Ludlow plus Pridoli. "The Working Group of the Regional Stratigraphic Chart of Northwest China (1976) identified Mutationella cf. podolica and Eospirifer tingi at one locality, and Cyrtina cf. praecedens, Camarotoechia, and Cyclospira at another locality. We are uncertain as to the reliability of these determinations, which would suggest a Lower Devonian rather than an Upper Silurian age."

• formation-level stratigraphic resolution

Environment/lithology: marine; siltstone and marl

• Correlation chart indicates BA 3 position.
• "consists of purplish-red, thick-bedded siltstone, sandy shale, and fine-grained sandstone, commonly with ripple marks, with a basal conglomerate. A few marls contain [corals and trilobites]."

Primary reference: E.-z. Mu, A. J. Boucot, X. Chen and J.-y. Rong. 1986. Correlation of the Silurian rocks of China. In A. J. Boucot and W. B. N. Berry (eds.), Geological Society of America Special Paper 202:1-80 [M. Foote/M. Foote/P. Wagner]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 27757: authorized by Michael Foote, entered by Michael Foote on 08.01.2003

Creative Commons license: CC BY (attribution)

Taxonomic list

Anthozoa
 Cystiphyllida - Tryplasmatidae
 Auloporida - Syringoporidae
Syringopora sp. Goldfuss 1826 tabulate coral
 Favositida - Favositidae
"Palaeofavosites hanhsiensis" = Paleofavosites, Favosites sp.
"Palaeofavosites hanhsiensis" = Paleofavosites tabulate coral
Favosites sp. Lamarck 1816 tabulate coral
Rhynchonellata
 Rhynchonellida - Camarotoechiidae
? Camarotoechia sp. Hall and Clarke 1893
 Atrypida - Cyclospiridae
? Cyclospira sp. Hall and Clarke 1893
 Spiriferinida - Cyrtinidae
 Spiriferida - Cyrtiidae
 Terebratulida - Meganterididae
Trilobita
 Corynexochida - Styginidae
Scutellum (Thysanopeltella) sp. Pusch 1833 trilobite