Reworked late Neogene Austrochlamys anderssoni (Mollusca Bivalvia) from northern James Ross Island, Antarctica

D. Pirrie*, H. A. Jonkers, J. L. Smellie, J. Alistair Crame, J. M. McArthur

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

Abstract

We report on the discovery of a new outcrop of fossiliferous Neogene sediments on northern James Ross Island, northern Antarctic Peninsula. Approximately 100 specimens of the pectinid bivalve Austrochlamys anderssoni (Hennig, 1911) were collected from the permafrost active layer. This bivalve species has a late Miocene to late Pliocene range and has previously been reported from both the glaciomarine Hobbs Glacier Formation and the interglacial Cockburn Island Formation in the James Ross Island area. The localized presence of abundant A. anderssoni within the permafrost suggests that the fossils have been frost heaved from an outcrop of either the Cockburn Island or the Hobbs Glacier formations, originally deposited on northern James Ross Island. The overall shell form, general absence of associated Antarctic Peninsula-derived clasts in the host sediment, and the measured Sr-87/(86) Sr isotope ratio of the shells (0.709050) which is indistinguishable from that for pectinid bivalves from the Cockburn Island Formation on Cockburn Island (0.709047) suggest that the shells were derived from a unit similar in age to the Cockburn Island Formation. This suggests that the Cockburn Island Formation was originally more laterally extensive than was previously known.

Original languageEnglish
Pages (from-to)180-187
Number of pages8
JournalAntarctic Science
Volume23
Issue number2
DOIs
Publication statusPublished - Apr 2011

Keywords

  • Cockburn Island Formation
  • fossil reworking
  • Hobbs Glacier Formation
  • late Miocene-Pliocene
  • permafrost
  • STRONTIUM ISOTOPE STRATIGRAPHY
  • INTERGLACIAL EVENTS
  • PENINSULA
  • PLIOCENE
  • DEPOSITS
  • AGE
  • OLIGOCENE
  • REGION
  • BASIN
  • MA

Fingerprint

Dive into the research topics of 'Reworked late Neogene Austrochlamys anderssoni (Mollusca Bivalvia) from northern James Ross Island, Antarctica'. Together they form a unique fingerprint.

Cite this