W 94-03, Seymour Island (Eocene of Antarctica)

Where: Antarctica (64.2° S, 56.7° W: paleocoordinates 63.4° S, 63.8° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: La Meseta Formation, Ypresian (56.0 - 47.8 Ma)

• Map location places it within Telm 4 or lower Telm 5. Diverse well preserved, nearly autochthonous molluscan, coral, asteroid fauna in thin-bedded, indurated clastics to W, unconsolidated channel sands with large slump blocks, scattered, displaced asteroids and echinoids to E.

• group of beds-level stratigraphic resolution

Environment/lithology: paralic; poorly lithified, shelly/skeletal sandstone and unlithified sandstone

• The environment of deposition of this complex unit has been subject to different interpretations, all agreeing in general that Telm5 represents a shallow-marine setting. A study by Wiedman and Feldmann (1988) on the ichnofossil fauna and depositional environment of the La Meseta Formation concluded that the Telm5 setting was a littoral to very shallow sublittoral clastic marine terrain, definitely above storm base and most probably above normal wave base. They agreed with Elliot and Trautrnan (1982) that Units II and III probably represent a tidally dominated environment, but evidence from sedimentary structures is also consistent with a barrier bar model and does not represent a shallowing upward sequence. Elliot and Trautman (1982) favored a deltaic model. The analysis of trace fossils and body fossils (including vertebrate remains and large, abundant wood fragments) indicates variable nearshore, shallow-marine environments. A scenario for the depositional environment could include a combination ebb-tidal (or possibly flood-tidal) delta-barrier island complex (Stillwell & Zinsmeister, 1992).
• Thin-bedded, indurated clastics to W, unconsolidated channel sands with large slump blocks to E.

Size class: macrofossils

Reposited in the USNM

Collection methods: bulk, mechanical

Primary reference: D. B. Blake and R. B. Aronson. 1998. Eocene stelleroids (Echinodermata) at Seymour Island, Antarctic Peninsula. Journal of Paleontology 72(2):339-353 [L. Ivany/E. Kowalski/L. Villier]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 7296: authorized by Linda Ivany, entered by Elizabeth Kowalski on 23.05.2000, edited by Loic Villier

Creative Commons license: CC BY (attribution)

Taxonomic list

Asteroidea
 Forcipulatida - Zoroasteridae
Zoroaster aff. fulgens Thomson 1873 sea star
 Forcipulatida - Asteriidae
Sclerasterias zinsmeisteri Blake and Aronson 1998 sea star
 Paxillosida - Astropectinidae
Ctenophoraster downeyae Blake and Zinsmeister 1979 sea star
 Valvatida - Goniasteridae
Buterminaster elegans Blake and Zinsmeister 1988 sea star
Probably not from this collection
Paragonaster clarkae n. sp. Blake and Aronson 1998 sea star