The main body and the New Fork and upper tongues of the Wasatch Formation and the Fontenelle, middle and upper tongues of the Green River Formation are recognized in the Cumberland Gap area. The main body of the Wasatch Formation corresponds to Oriel's La Barge Member of the Wasatch Formation. The main body is a flood plain deposit derived from tectonically active areas to the W. of the basin. Both the New Fork and the upper tongues of the Wasatch Formation are delta deposits that extend from their source areas, the Wind River Mountains and the Uinta Mountains respectively. The upper tongue and probably the New Fork are divisible into beds deposited in terrestrial areas and areas of lacustrine fluctuation. The terrestrial beds (nearest the source) are brilliant red beds, and the beds deposited in areas of lacustrine fluctuation (furthest from the source) are drab-green and variegated red and green beds. The New Fork and upper tongues of the Wasatch Formation were deposited in response to tectonic uplift and not in response to a retreat of the lake shore. During Green River time, the first significant uplift was in the Wind River Mountains (as marked by the New Fork tongue) and this was followed by major uplift in the Uinta Mountains (as marked by the upper tongue of the Wasatch Formation).

This content is PDF only. Please click on the PDF icon to access.

First Page Preview

First page PDF preview
You do not currently have access to this article.