Abstract

A lineament, herein called the Towanta Lineament, was first noticed on a composite raised relief map of Utah and has been traced on aerial and satellite photography and topographic maps for about 220 miles (350 kms.). Parts of the eastern half have been examined in the field.

The lineament extends from about 20 miles (32 kms.) northeast of Vernal near the northeast corner of Utah to within about 40 miles (65 kms.) of the Utah-Nevada border. Except where apparently offset by the Wasatch Fault (or Line), the strike is consistently N 72° E.

The lineament cuts a wide variety of structural features and stratigraphic units and is everywhere characterized by topographically low areas which have developed into linear drainages. Along the south flank of the Uinta Mountains and across the northwest Uinta Basin it is marked by springs, lines of sinkholes, caves, anomalous drainage patterns and, in one instance, fault scarps of Recent age a short distance to the south. A wide zone of nearly parallel fractures crosses the deepest part of the Uinta Basin in this northwest portion and is probably a controlling factor in prolific oil and gas production.

The Wasatch Fault apparently has been offset by right lateral movement along the lineament, and the lineament has been in turn offset by left lateral movement along the Wasatch Fault. The Utah Valley area south of Provo thus appears to be an important structural junction.

West of the Wasatch Fault, the lineament crosses Basin and Range structures and is marked by major mineralized areas, intrusions, pronounced fracturing and strong contrast in aeromagnetic characteristics of the terrane on opposite sides of the trace.