By: T. J. Felger, M. N. Machette, and M. L. Sorensen
The Mona quadrangle in central Utah includes part of the southern Wasatch Mountains, Wasatch fault, and northern Juab Valley. Bedrock in the eastern half of the quadrangle consists of approximately 29,000 feet of carbonate and clastic sedimentary rocks that range in age from Precambrian to Jurassic. A small area of Tertiary volcanic rocks is exposed in the northwestern comer of the quadrangle. Most of the western half of the quadrangle is occupied by Juab Valley, which contains as much as 5,200 feet of Tertiary and Quaternary deposits.
The steeply west-dipping Wasatch fault zone trends slightly east of north through the quadrangle and separates Juab Valley on the west from the Wasatch Mountains on the east. Recent movement on the fault is demonstrated by fault scarps that are preserved on Holocene (and older) alluvium at the mouths of almost all drainages along the front of the Wasatch Range.
Pages: 23 p.
Plates: 2 pl.
Location: Juab County and Utah County
Media Type: Paper Map