San Nicholas Island (SN-14) (Quaternary of the United States)

Also known as Vedder & Norris (1963) SN-14

Where: Ventura County, California (33.2° N, 119.5° W: paleocoordinates 33.2° N, 119.2° W)

• coordinate stated in text

• outcrop-level geographic resolution

When: Unnamed Formation, Quaternary (2.6 - 0.0 Ma)

• Dune sand and fossiliferous marine terrace deposits of Quaternary age. These overlie Eocene strata. Fossils come from seven well-developed wave-cut platforms at altitudes of 25 to 990 feet. Several submerged terraces are present on the shelf adjacent to the island., the lowest being 400 ft below sea-level. Presumably all the terrace platforms on San Nicholas Island were cut later than the middle Pleistocene diastrophism recognized elsewhere in southern California. Terrace platforms are covered with a variety of sediments of marine and non-marine origin and range in thickness from a few inches to many feet.

• bed-level stratigraphic resolution

Environment/lithology: coastal; pebbly, shelly/skeletal, conglomeratic, calcareous sandstone

• Higher emergent terraces may represent wave-abraded platforms that were eroded during eustatic changes in sea level combined with tectonic uplift. The lowest emergent terrace may have been cut during eustatic sea-level changes followed by very slight regional seaward warping. Presumably all the terrace platforms on San Nicholas Island were cut later than the middle Pleistocene diastrophism recognized elsewhere in southern California
• Generally comprise poorly sorted calcareous sand and gravel composed primarily of mollusc shell fragments, echinoid plates and spines, calcareous algae, and bryozoans.

Size class: macrofossils

Collection methods: quarrying,

• Collections made by Norris (1955). Earlier collections by Cooper (1894), and Howard (1955)

Primary reference: J. G. Vedder and R. M. Norris. 1963. Geology of San Nicolas Island, California. United States Geological Survey Professional Paper 369:1-65 [A. Miller/A. Hendy/P. Wagner]more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 37936: authorized by Austin Hendy, entered by Austin Hendy on 27.03.2004

Creative Commons license: CC BY (attribution)

Taxonomic list

• Comprehensive for invertebrates
 Arcida - Glycymerididae
"Glycymeris cf. subobsoleta" = Glycymeris (Axinola) septentrionalis
"Glycymeris cf. subobsoleta" = Glycymeris (Axinola) septentrionalis Middendorf 1849 clam
 Pectinida - Pectinoidae
"Pecten diegensis" = Euvola diegensis
"Pecten diegensis" = Euvola diegensis Dall 1898 scallop
 Carditida - Carditidae
Miodontiscus prolongatus Carpenter 1864 clam
 Cardiida - Veneridae
Saxidomus ? nuttalli Conrad 1837 venus clam
Turtonia cf. minuta Fabricius 1780 venus clam
 Cardiida - Lasaeidae
"Lasaea cf. cistula" = Lasaea adansoni
"Lasaea cf. cistula" = Lasaea adansoni Gmelin 1791 clam
 Lucinida - Lucinidae
Epilucina californica Conrad 1837 clam
 Patellogastropoda - Lottiidae
Acmaea sp. n. sp. Eschscholtz 1830 limpet
Acmaea mitra Eschscholtz 1833 limpet
  - Siphonaliidae
Calicantharus fortis Carpenter 1866 snail
 Neogastropoda - Olividae
"Olivella biplicata" = Olivella (Callianax) biplicata
"Olivella biplicata" = Olivella (Callianax) biplicata Sowerby 1825 olive snail
 Neogastropoda - Columbellidae
Amphissa versicolor Dall 1871 snail
 Neogastropoda - Fasciolariidae
Barbarofusus ? arnoldi Cossmann 1903 snail
 Neogastropoda - Cystiscidae
 Neogastropoda - Muricidae
Thais emarginata murex snail
Ocenebra cf. lurida murex snail
Ocenebra ? interfossa murex snail
Subspecies: Ocenebra interfossa clathrata
 Neogastropoda - Mangeliidae
"Mangelia aff. rhyssa" = Cythara (Mangelia), "Mangelia fuscoligata" = Cythara (Mangelia), Mangelia variegata
"Mangelia aff. rhyssa" = Cythara (Mangelia) snail
"Mangelia fuscoligata" = Cythara (Mangelia) snail
Mangelia variegata Carpenter 1864 snail
 Littorinoidea - Littorinidae
Littorina ? scutulata Gould 1849 periwinkle
 Vanikoroidea - Hipponicidae
Hipponix antiquatus Linnaeus 1767 hoof shell
 Naticoidea - Naticidae
"Cryptonatica cf. clausa" = Cryptonatica affinis
"Cryptonatica cf. clausa" = Cryptonatica affinis Gmelin 1791 moon snail
 Calyptraeoidea - Calyptraeidae
Crepidula adunca Sowerby 1824 slipper shell
Crepidula ? onyx Sowerby 1824 slipper shell
 Rissooidea - Barleeidae
 Rissooidea - Rissoidae
 Rissooidea - Vitrinellidae
 Truncatelloidea - Caecidae
 Sorbeoconcha - Cerithiidae
Bittium cf. eschrichtii cerith snail
Subspecies: Bittium eschrichtii montereyense
Bittium ? armillatum cerith snail
Bittium attenuatum cerith snail
 Pyramidelloidea - Pyramidellidae
 Turbinoidea - Turbinidae
Astraea cf. gibberosa Dillwyn 1817 red turban
 Turbinoidea - Phasianellidae
 Fissurelloidea - Fissurellidae
Fissurella volcano Reeve 1849 snail
 Trochoidea - Trochidae
Pupillaria cf. optabilis Carpenter 1864 top snail
 Neoloricata - Mopaliidae
Mopalia muscosa Gould 1846 chiton
Mopalia cf. hindsii Sowerby 1847 chiton
 Scleractinia - Dendrophylliidae
Balanophyllia elegans Verrill 1864 stony coral