Earth:Goler Formation

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Goler Formation
Stratigraphic range: Paleogene
TypeFormation
UnderliesRicardo Group (unconformity)
OverliesGarlock Formation (unconformity)
Lithology
Primaryconglomerate, sandstone
Othersiltstone, mudstone
Location
RegionCalifornia
CountryUnited States

The Goler Formation is a Paleogene geologic formation in California. It outcrops in the El Paso Mountains in the Mojave Desert near Ridgecrest. Fossils of mammals, reptiles, and cartilaginous fish are found in a few late Paleocene (Tiffanian age) sites from this formation, representing the best terrestrial Paleocene deposits in California.[1]

Geology

The Goler Formation is split into four members (subunits), labelled 1-4, with member 4 divided further into 4a-4d. The oldest members (1-2) lack fossils, and they probably represent alluvial fan environments eroding down into older canyons of granite and metamorphic rock. Fossils are found in members 3 and 4, which represent braided rivers and streams flowing down from the west in a warm monsoonal climate with strong wet and dry seasons. During the Paleocene, the Goler Formation was not far from the coast, but the predecessors of the Sierra Nevada further west created a rain shadow over the area. By the time of member 4d, the area was submerged by rising sea levels.[2]

Paleobiota

Nearly all fossils from the Goler Formation are concentrated into members 4a and 4b (the Goler Assemblage), with the exception of indeterminate turtles from member 3 and a Phenacodus tooth from member 4d.[1] Members 4a and 4b are probably Tiffanian (Ti3-Ti5) in age, around the start of the late Paleocene. Member 4d could be any time between Tiffanian 5 and Bridgerian (early-mid Eocene) in age.[1]

Mammals

The most abundant mammal fossils are Phenacodus cf. bisoneri and Nannodectes lynasi.[1]

Mammals of the Goler Formation
Genus / Taxon Species Strata Notes Images
Arctocyonidae? indet. Member 4b An indeterminate possible arctocyonid.
Bessoecetor B. septentrionalis Member 4a A pantolestid.
Dissacus D. sp. Member 4a A mesonychid.
Golerdelphys G. stocki Member 4b A herpetotheriid.
Goleroconus G. alfi Member 4a, 4b A periptychid.
Ignacius I. frugivorus Member 4b A paromomyid.
Lambertocyon L. cf. gingerichi Member 4a An arctocyonid.
Mimotricentes M. tedfordi Member 4a An arctocyonid.
Nannodectes N. lynasi Member 4a, 4b A plesiadapid.
Paromomys P. depressidens Member 4a A paromomyid.
Peradectes P. sp. Member 4a, 4b A peradectid.
Phenacodus P. cf. bisonensis Member 4a, 4b A phenacodontid.
P. cf. grangeri Member 4a
P. cf. matthewi Member 4a
P. cf. vortmani Member 4d
Promioclaenus P. walshi Member 4a A hyopsodontid.
Protictis P. cf. agastor Member 4a A viverravid.
P. paralus
Protoselene P. ashtoni Member 4a A hyopsodontid.
Stylinodontidae indet. Member 4a An indeterminate stylinodontid.
Thryptacodon T. sp. Member 4a An oxyclaenid.

See also

  • List of fossiliferous stratigraphic units in California
  • Paleontology in California

References


  1. 1.0 1.1 1.2 1.3 Lofgren, Donald; Mckenna, Malcolm; Honey, James; Nydam, Randall; Wheaton, Christine; Yokote, Bryan; Henn, Lexington; Hanlon, Whitney et al. (2014-02-06). "New Records of Eutherian Mammals from the Goler Formation (Tiffanian, Paleocene) of California and Their Biostratigraphic and Paleobiogeographic Implications" (in en). American Museum Novitates 3797 (3797): 1–57. doi:10.1206/3797.1. ISSN 0003-0082. http://www.bioone.org/doi/abs/10.1206/3797.1. 
  2. Torres, M. A.; Gaines, R. R. (2013-07-29). "Paleoenvironmental and Paleoclimatic Interpretations of the Late Paleocene Goler Formation, Southern California, U.S.A., Based On Paleosol Geochemistry" (in en). Journal of Sedimentary Research 83 (8): 591–605. doi:10.2110/jsr.2013.48. ISSN 1527-1404. https://web.gps.caltech.edu/~jstock/Ge136a-2013/TorresGaines2013-JSed.pdf.