Also known as Was: Road River Fm., Bryograptus and Clonograptus zones, lower Arenig, Richardson Mtn

Where: Yukon, Canada (68.2° N, 137.0° W: paleocoordinates 9.8° N, 52.7° W)

• coordinate based on political unit

When: Bryograptus - Clonograptus graptolite zone, Lower Road River Formation (Road River Group), Arenig (478.6 - 466.0 Ma)

• "prob. Lower Arenig." Road River is really a group, but not all of it has been split into new formations. In this zonation scheme, the Bryograptus - Clonograptus zone was beneath the Tetragraptus approximatus zone and above the Staurograptus zone. This probably spans the Anisograptus matanensis to Paradelograptus kinnegraptoides zones given Jackson & Lenz 2006.

• formation-level stratigraphic resolution

Environment/lithology: marine; cherty/siliceous limestone and shale

Size class: macrofossils

Primary reference: D. E. Jackson and A. C. Lenz. 1962. Zonation of Ordovician and Silurian graptolites of northern Yukon, Canada. AAPG Bulletin 46:30-45 [M. Uhen/J. Ju/M. Uhen]more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 288: authorized by Jack Sepkoski, entered by Mike Sommers on 20.11.1998

Creative Commons license: CC BY (attribution)