San Nicholas Island (SN-11) (Quaternary of the United States)

Also known as Vedder & Norris (1963) SN-11

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 Vedder et al (1955-1956). 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 37939: authorized by Austin Hendy, entered by Austin Hendy on 27.03.2004

Creative Commons license: CC BY (attribution)

Taxonomic list

• Comprehensive for invertebrates
 Sessilia - Tetraclitidae
Tetraclita ? squamosa barnacle
Subspecies: Tetraclita squamosa rubescens
 Mytilida - Mytilidae
Mytilus californianus Conrad 1837 mussel
Septifer bifurcatus Conrad 1837 mussel
"Modiolus cf. fornicatus" = Modiolus (Modiolus) carpenteri Soot-Ryen 1963 mussel
 Carditida - Carditidae
"Glans subquadrata" = Glans carpenteri
"Glans subquadrata" = Glans carpenteri Lamy 1922 clam
 Cardiida - Veneridae
"Protothaca staminea" = Leukoma staminea, "Ventricolaria fordii" = Globivenus fordii, "Irus cf. lamellifer" = Irusella lamellifera, "Transennella tantilla" = Nutricola tantilla
"Protothaca staminea" = Leukoma staminea Conrad 1837 venus clam
"Ventricolaria fordii" = Globivenus fordii Yates 1890 venus clam
"Irus cf. lamellifer" = Irusella lamellifera Conrad 1837 venus clam
"Transennella tantilla" = Nutricola tantilla Gould 1853 venus clam
 Cardiida - Semelidae
Cumingia californica Conrad 1837 clam
 Cardiida - Neoleptonidae
Bernardina bakeri Dall 1910 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 digitalis Eschscholtz 1833 limpet
Acmaea mitra Eschscholtz 1833 limpet
Acmaea cf. pelta Eschscholtz 1833 limpet
  - Siphonaliidae
Calicantharus fortis Carpenter 1866 snail
 Opisthobranchia - Retusidae
"Coleophysis ? harpa" = Retusa (Coleophysis)
"Coleophysis ? harpa" = Retusa (Coleophysis) snail
 Triphoroidea - Cerithiopsidae
Cerithiopsis sp. Hanley 1849 snail
 Neogastropoda - Olividae
"Olivella biplicata" = Olivella (Callianax) biplicata
"Olivella biplicata" = Olivella (Callianax) biplicata Sowerby 1825 olive snail
 Neogastropoda - Columbellidae
Mitrella cf. tuberosa Carpenter 1864 snail
Amphissa versicolor Dall 1871 snail
 Neogastropoda - Fasciolariidae
Barbarofusus ? arnoldi Cossmann 1903 snail
 Neogastropoda - Mitridae
"Mitra idae" = Mitra (Atrimitra) idae
"Mitra idae" = Mitra (Atrimitra) idae Melville 1893 mitre shell
 Neogastropoda - Muricidae
 Neogastropoda - Pseudolividae
 Neogastropoda - Mangeliidae
? Cytharella sp., "Mangelia ? interfossa" = Cythara (Mangelia), "Mangelia cf. nitens" = Cythara (Mangelia), Mangelia cf. variegata
? Cytharella sp. Monterosato 1875 snail
"Mangelia ? interfossa" = Cythara (Mangelia) snail
"Mangelia cf. nitens" = Cythara (Mangelia) snail
Mangelia cf. variegata Carpenter 1864 snail
 Neogastropoda - Mitromorphidae
 Neogastropoda - Conidae
"Conus californicus" = Californiconus californicus
"Conus californicus" = Californiconus californicus Reeve 1844 cone shell
 Littorinoidea - Littorinidae
Littorina planaxis Philippi 1847 periwinkle
Littorina cf. scutulata Gould 1849 periwinkle
 Vanikoroidea - Hipponicidae
Hipponix antiquatus Linnaeus 1767 hoof shell
 Vanikoroidea - Eulimidae
 Velutinoidea - Triviidae
"Pusula californiana" = Pseudopusula californiana
"Pusula californiana" = Pseudopusula californiana Gray 1827 snail
 Vermetoidea - Vermetidae
 Calyptraeoidea - Calyptraeidae
Crepipatella lingulata Gould 1846 slipper shell
Crepidula adunca Sowerby 1824 slipper shell
Crepidula onyx Sowerby 1824 slipper shell
 Rissooidea - Barleeidae
 Rissooidea - Rissoidae
 Rissooidea - Vitrinellidae
 Truncatelloidea - Caecidae
Caecum sp. Fleming 1813 snail
 Sorbeoconcha - Cerithiidae
Bittium armillatum cerith snail
Bittium attenuatum cerith snail
 Pulmonata - Trimusculidae
 Basommatophora - Siphonariidae
 Pyramidelloidea - Pyramidellidae
 Haliotoidea - Haliotidae
 Turbinoidea - Turbinidae
 Turbinoidea - Phasianellidae
 Fissurelloidea - Fissurellidae
Fissurella volcano Reeve 1849 snail
Diodora aspera Rathke 1833 snail
Puncturella cf. cooperi Carpenter 1864 puncturella
 Trochoidea - Trochidae
Pupillaria cf. optabilis Carpenter 1864 top snail
Tegula gallina Forbes 1850 top snail
Subspecies: Tegula gallina multifilosa
 Trochoidea - Tegulidae
 Neoloricata - Mopaliidae
Mopalia cf. muscosa Gould 1846 chiton
 Neoloricata - Callistoplacidae
Callistochiton crassicostatus Pilsbry 1893 chiton
 Neoloricata - Acanthochitonidae
"Cryptochiton" stelleri Middendorf 1847 chiton
 Camarodonta - Strongylocentrotidae
Strongylocentrotus ? purpuratus Arnold 1903 sea urchin
 Scleractinia - Dendrophylliidae
Balanophyllia elegans Verrill 1864 stony coral