Upper Jurassic, Alaska Range (USGS 5723) - (Moffit (1954) (Jurassic of the United States)

Also known as USGS 5723(#08A M-F27)

Where: Valdez-Cordova County, Alaska (62.4° N, 142.9° W: paleocoordinates 37.2° N, 83.2° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Late/Upper Jurassic (163.5 - 145.0 Ma)

• Upper Jurassic rocks laid down unconformably on an eroded surface of older rocks. They are deeply eroded, intruded by igneous rocks, and effected strongly by regional faulting. The areal extent of Mesozoic rocks in teh Alaska mountains suggests a thickness exceeding thousands of feet.

• bed-level stratigraphic resolution

Environment/lithology: marine; wackestone and sandstone

• Fossiliferous greywacke or feldspathic sandstone, associated with bed of conglomerate containing boulders of dark fine-grained basaltic rock and deeply weathered granite.

Size class: macrofossils

Reposited in the USGS

Collection methods: quarrying,

• Several collections of fossils from the Nutzotin Mountains contain forms that are too poorly preserved for definite determination. Collected by A. Knopf(1908)

Primary reference: F.H. Moffit. 1954. Geology of the eastern part of the Alaska Range and adjacent area. United States Geological Survey Professional Paper 989(D) [A. Miller/A. Hendy/A. Hendy]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 41218: authorized by Austin Hendy, entered by Austin Hendy on 08.07.2004

Creative Commons license: CC BY (attribution)

Taxonomic list

• Representative of mollusca, of which are poorly preserved
Bivalvia
 Pectinida - Buchiidae