Powerline Road Tom Quarry (Neogene of the United States)

Also known as LACM 3776

Where: Kern County, California (35.4° N, 118.0° W: paleocoordinates 35.3° N, 115.2° W)

• coordinate stated in text

When: Dove Spring Formation, Hemphillian (10.3 - 4.9 Ma)

• The type was collected from a light tan siliceous sandy mudstone in the upper part of the Dove Spring Formation. Fossils from this locality are concentrated in small pockets along the bedding plane. Stratigraphically, locality LACM 3776 is bracketed by two volcanic ashes, Ash 15 (fission-track dated 8.4 ± 1.4 Ma) and Ash 16 (K/Ar dated at 8.50 ± 0.13 Ma) (Whistler, 1969; Burbank and Whistler, 1987; Whistler, 1991; Whistler and Burbank, 1992). Ashes 15 and 16 are separated by 258 m of strata in the vicinity of locality LACM 3776, and the locality is 123 m below Ash 16. Locality LACM 3776 falls within a paleomagnetically reversed zone that can be correlated to the paleomagnetic Chron C4Ar.1n, which has a revised age range of 9.230–9.308 Ma (Cande and Kent, 1995). Ash 16 falls within a normal magnetic interval that can be correlated to paleomagnetic Chron C4An with a revised age range of 8.699–9.025 Ma (Cande and Kent, 1995), consistent with the K/Ar date presented by Whistler and Burbank (1992). These magnetic correlations suggest that the fission-track date of 8.4 ± 1.8 Ma for Ash 15 presented by Whis- tler and Burbank (1992) is anomalously young. Thus, the best estimate of age for locality LACM 3776 is between 9.2 and 9.3 Ma (early late Miocene).

Environment/lithology: terrestrial; sandy, cherty/siliceous mudstone

• The type was collected from a light tan siliceous sandy mudstone in the upper part of the Dove Spring Formation. Fossils from this locality are concentrated in small pockets along the bedding plane

Size class: macrofossils

Primary reference: X. Wang, D. P. Whistler, and G. T. Takeuchi. 2005. A New Basal Skunk Martinogale (Carnivora, Mephitinae) From Late Miocene Dove Spring Formation, California, and Origin of New World Mephitines. Journal of Vertebrate Paleontology 25(4):936-949 [J. Marcot/J. Marcot]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 163573: authorized by Jonathan Marcot, entered by Jonathan Marcot on 04.11.2014

Creative Commons license: CC BY (attribution)

Taxonomic list

Mammalia
 Carnivora - Mephitidae
Martinogale faulli n. sp. Wang et al. 2005 skunk
 Carnivora - Canidae
Aelurodon sp. Leidy 1858 bone-crushing dog
LACM 150925