Also known as Takuan Formation ("Songkan Member") at Huanggexi, Daguan Co., NE Yunnan Prov.

Where: Yunnan, China (27.7° N, 103.9° E: paleocoordinates 11.2° N, 127.7° E)

• coordinate based on political unit

• local area-level geographic resolution

When: Monograptus sedgwickii graptolite zone, Songkan Member (Takuan Formation), Aeronian (440.8 - 438.5 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. Revised usage of Takuan Formation to restrict it so Songkan, Huanggexi, and Sifengya units (from bottom to top). Daluzhai is regarded as synonym of Xiushan Formation. "We conclude that this unit [Songkan] corresponds to about the zone of Monograptus sedgwickii."

• member-level stratigraphic resolution

Environment/lithology: marine; gray, argillaceous limestone and argillaceous, calcareous siltstone

Size class: macrofossils

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 27849: authorized by Michael Foote, entered by Michael Foote on 14.01.2003

Creative Commons license: CC BY (attribution)