First record of the Eocene pteropod Heliconoides nitens (Gastropoda: Thecosomata: Limacinidae) from the Pacific Basin

Year:

2013

Type of Publication:

Article

Keywords:

biostratigraphy; Humptulips Formation; hydrocarbon seep; Olympic Peninsula; Washington State

Authors:

Goedert, James L.; Peckmann, Joern; Benham, Steven R.; Janssen, Arie W.

Journal:

PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON

Volume:

126

Number:

1

Pages:

72-82

Month:

MAR 19

ISSN:

0006-324X

BibTex:

@article{ISI:000316713400006, author = "James L. Goedert and Joern Peckmann and Steven R. Benham and Arie W. Janssen", abstract = "Fossils of a single pteropod species were found in an isolated carbonate deposit within middle Eocene deep-water strata of the Humptulips Formation in western Washington State, U.S.A. The carbonate formed at a cold seep where fluids containing high concentrations of hydrocarbons, principally methane, emanated from the seafloor. Anaerobic oxidation of the methane by prokaryotes caused localized and rapid precipitation of calcium carbonate that encased biogenic detritus including wood fragments and mollusk shells; in this case even the minute and delicate aragonitic shells of the pteropod Heliconoides nitens (Lea, 1833), the first certain record of this taxon for the Pacific Basin. The presence of H. nitens in the Humptulips Formation allows us to recalibrate the age of the formation as late Lutetian or early Bartonian, up to 8 million years younger than previously thought. Heliconoides nitens has been found in temporally equivalent strata elsewhere in the world, and this is another example of some fossil pteropods having utility for long distance biostratigraphic correlations. Pteropod shells rapidly dissolve in deep-water environments, thus cold seep deposits may be a source of pteropod fossils in deep-water strata where they otherwise would not occur.", address = "NAT MUSEUM NAT HIST SMITHSONIAN INST, WASHINGTON, DC 20560 USA", issn = "0006-324X", journal = "PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON", keywords = "biostratigraphy; Humptulips Formation; hydrocarbon seep; Olympic Peninsula; Washington State", month = "MAR 19", number = "1", pages = "72-82", publisher = "BIOL SOC WASHINGTON", title = "{F}irst record of the {E}ocene pteropod {H}eliconoides nitens ({G}astropoda: {T}hecosomata: {L}imacinidae) from the {P}acific {B}asin", type = "Article", volume = "126", year = "2013", }

Abstract:

Fossils of a single pteropod species were found in an isolated carbonate deposit within middle Eocene deep-water strata of the Humptulips Formation in western Washington State, U.S.A. The carbonate formed at a cold seep where fluids containing high concentrations of hydrocarbons, principally methane, emanated from the seafloor. Anaerobic oxidation of the methane by prokaryotes caused localized and rapid precipitation of calcium carbonate that encased biogenic detritus including wood fragments and mollusk shells; in this case even the minute and delicate aragonitic shells of the pteropod Heliconoides nitens (Lea, 1833), the first certain record of this taxon for the Pacific Basin. The presence of H. nitens in the Humptulips Formation allows us to recalibrate the age of the formation as late Lutetian or early Bartonian, up to 8 million years younger than previously thought. Heliconoides nitens has been found in temporally equivalent strata elsewhere in the world, and this is another example of some fossil pteropods having utility for long distance biostratigraphic correlations. Pteropod shells rapidly dissolve in deep-water environments, thus cold seep deposits may be a source of pteropod fossils in deep-water strata where they otherwise would not occur.