Lincoln (UGSG 18908) - #111 (Moore, 1963) (Miocene of the United States)

Also known as Locality #111 (Moore, 1963); USGS 18908

Where: Lincoln County, Oregon (44.7° N, 124.1° W: paleocoordinates 44.5° N, 119.4° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Astoria Formation, Middle Miocene (16.0 - 11.6 Ma)

• From middle of 22 ft of siltstone, about 51 ft above base of exposed section in beach cliffs. From an unknown horizon. Astoria Formation has been used as a name for almost all of the marine middle Miocene sedimentary rocks of Washington and Oregon although these correlations are poorly constrained. The formation has been divided into three members: a lower sandstone, a shale, and an upper sandstone. These rocks form the northern limb of a syncline, the asis of which is exposed east of Astoria, and the syncline trends NE and plunges to the SW. The Astoria Formation is intermittently exposed; theya re faulted and exposures are interupted by volcanic rocks and slides. The maximum thickness of any exposure is 25 feet.

• bed-level stratigraphic resolution

Environment/lithology: coastal; poorly lithified, fine-grained, sandy siltstone

• Astoria Formation is faulted and interupted in exposure by volcanic rocks and land slides.
• Siltstone. Strata exposed consist of shale varying in silt and sand content, siltstone, fine-grained sandstone with varying amounts of silt, coarse-grained sandstone, conglomerate, and tuff. Calcareous silty shale and fine-grained silty sandstone generally predominate.

Size class: macrofossils

Preservation: concretion, replaced with other

Reposited in the CAS, USNM

Collection methods: quarrying, surface (float),

• Collected by E.J. Moore, 1952. Collections reside in the Californian Academy of Sciences, the U.S. National Museum, and presumably the USGS.

Primary reference: E. J. Moore. 1963. Miocene marine mollusks from the Astoria Formation in Oregon. United States Geological Survey Professional Paper 419 [A. Miller/A. Hendy/A. Hendy]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 39798: authorized by Austin Hendy, entered by Austin Hendy on 06.06.2004

Creative Commons license: CC BY (attribution)

Taxonomic list

• Exhaustive for mollusca
Bivalvia
 Arcida - Arcidae
 Cardiida - Veneridae
 Cardiida - Tellinidae
"Macoma arctata" = Macoma (Psammacoma) arctata
"Macoma arctata" = Macoma (Psammacoma) arctata Conrad 1849 tellin clam
 Hiatellida - Hiatellidae
"Panope (Panope) abrupta" = Panopea abrupta
"Panope (Panope) abrupta" = Panopea abrupta Conrad 1849 clam
 Nuculida - Nuculidae
Acila (Truncacila) conradi Meek 1864 divaricate nutclam
Gastropoda
 Cephalaspidea - Retusidae
"Cylichnina petrosa" = Retusa (Cylichnina)
"Cylichnina petrosa" = Retusa (Cylichnina) snail
 Neogastropoda - Buccinidae
 Neogastropoda - Fasciolariidae
 Calyptraeoidea - Calyptraeidae
Crepidula praerupta Conrad 1849 slipper shell