About This Item

Share This Item

The AAPG/Datapages Combined Publications Database

AAPG Bulletin

Abstract


Volume: 29 (1945)

Issue: 7. (July)

First Page: 1019

Last Page: 1027

Title: Occurrence of Middle Jurassic Rocks in Western Interior of United States

Author(s): Ralph W. Imlay (2)

Abstract:

The occurrence of Middle Jurassic rocks in the Western Interior region of the United States is shown by the presence of the Bajocian ammonites, Stemmatoceras and Defonticeras, in the Twin Creek limestone of southeastern Idaho. The occurrence of Middle Jurassic rocks of the Bathonian stage is indicated by the presence of the ammonites, Arctocephalites and Cranocephalites, in the lower part of the Ellis formation of Montana. Marine Jurassic deposits older than the Bathonian appear to have been limited to the central part of the sedimentary trough and will probably be found only along the border area of Idaho and Wyoming, in north-central Utah, and in southwestern Montana.

Pay-Per-View Purchase Options

The article is available through a document delivery service. Explain these Purchase Options.

Watermarked PDF Document: $14
Open PDF Document: $24

AAPG Member?

Please login with your Member username and password.

Members of AAPG receive access to the full AAPG Bulletin Archives as part of their membership. For more information, contact the AAPG Membership Department at [email protected].