Where: San Diego County, California (32.8° N, 117.2° W: paleocoordinates 33.5° N, 103.2° W)

• coordinate stated in text

When: Ardath Formation (La Jolla Group), Lutetian (47.8 - 41.3 Ma)

• Formerly in the Rose Canyon Member. The Rose Canyon included most of what is now the Mount Soledad, Ardath, Scripps, and Friars Formations. Fossil is presumably from the Ardath Shale, which is richly fossiliferous. Abundant fossils of several phyla (Hanna, 1926; Bukry and Kennedy, 1969) lead us to assign a middle Eocene age to the Ardath Shale. For example, a coccolith assemblage approximately from the middle of the formation at a meander-bend cutbank on the east side of Rose Canyon about 300 m north of the Ardath Road overpass contains Helicopontosphaera lophota (Bramlette and Sullivan) and indicates, when considered together with other species in the assemblage, an early middle Eocene age (David Bukry, written commun., 1969). A molluscan assemblage from 26 m below the top of the Ardath Shale in its type section includes Turritella uvasana applinae Hanna, Ficopsis cooperiana Stewart, and Tejonia lapllaensis (Stewart). These species are restricted to the middle Eocene Domengine Stage (C. R. Givens, written commun., 1970).

• bed-level stratigraphic resolution

Environment/lithology: submarine fan; lithified shale

Size class: macrofossils

Collected by M. A. Hanna; reposited in the UCMP

Primary reference: M. A. Hanna. 1927. An Eocene invertebrate fauna from the La Jolla Quadrangle, California . University of California Publications Bulletin of the Department of Geological Sciences 16(8):247-398 [J. Marcot/J. Marcot]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 166459: authorized by Matthew Clapham, entered by Kristina Okamoto on 14.02.2015, edited by Jonathan Marcot

Creative Commons license: CC BY (attribution)