Geologic Map of the West Half of the Loa 30' x 60' Quadrangle, Garfield, Piute, and Wayne Counties, Utah (M-292DM)

The west half of the Loa 30'x60' quadrangle covers the Awapa Plateau and adjacent areas along the southeast flank of the Marysvale volcanic field west of Capital Reef National Park. The gently east-tilted plateau is bounded on the west by the Paunsaugunt fault zone and on the east by the Thousand Lake fault zone, both active normal faults that have significant Quaternary displacement. Parts of Boulder Mountain, which supported an ice cap during the last glacial maximum, and the Monroe Peak caldera, source of the Osiris Tuff, the most distinctive and widespread ash-flow tuff in the volcanic field, are in the map area. This geologic map and explanation highlight the volcanic history of this region, which includes elements of basin-range, Colorado Plateau, and Marysvale volcanic field structure and stratigraphy. 

Published: 2023

Pages: 42

Plates: 2

Scale: 1:62,500

Location: Utah

Media Type: Paper Map with report