Quaternary Fault and Fold Database
of the United States (outside link)

Utah is in a tectonically active region where the Intermountain seismic belt (ISB), a north-trending zone of historical seismicity, bisects the state.

The ISB coincides with the broad transitional eastern margin (including the Basin and Range-Colorado Plateau transition zone) of the Basin and Range Physiographic Province, extending from southern Nevada, through Utah, southeastern Idaho, western Wyoming, and into central Montana.

Earthquake epicenters and Quaternary tectonic features in relation to the Intermountain seismic belt.
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It includes the major active faults of Utah, such as the Wasatch fault system in northern Utah, and the Hurricane and Sevier faults in southern Utah and northern Arizona.

The Wasatch Front region includes Quaternary tectonic features within a 200-km- (125 mi) wide zone in northern Utah, centered on the Wasatch fault.

The Wasatch fault zone, a normal fault with predominantly vertical movement, is the longest (340 km [210 mi]) and most tectonically active structure in Utah, with abundant evidence of surface-rupturing events during the Holocene.

More than two-dozen other faults in the Wasatch Front region show evidence of one or more latest Pleistocene to Holocene surface-rupturing events.

In west-central Utah, latest Pleistocene to Holocene faulting events have been distributed across a series of fault zones spanning about 50 km (30 mi) wide. Based upon the extent and style of this faulting, the west-central Utah source region may extend eastward from Gunnison Lake near Manti to the Joes Valley area near the Emery-Sanpete County line, eastward from the southern part of the Wasatch fault zone.

Quaternary tectonism has been largely absent from eastern Utah, which includes the Uinta Mountains portion of the Middle Rocky Mountains province and much of the interior of the Colorado Plateau province.

In the Paradox Basin, however, late Tertiary to Quaternary dissolution and collapse of large salt anticlines and salt flowage has continued locally into the late Quaternary, creating a series of northwest-southeast-aligned fault structures.

Eastern Utah, like most of the Colorado Plateau, may lie east of the significant extensional forces of the Basin and Range, or may be underlain by more coherent crust.

In southwestern Utah, the Hurricane, Sevier, and Paunsaugunt faults are the dominant Quaternary structural features in the region. The Hurricane fault and its northward continuation, the Cedar City-Parowan monocline and the Paragonah fault, are considered by some workers to represent the boundary between the Basin and Range and Colorado Plateau Provinces. Others place this system within the Basin and Range-Colorado Plateau transition zone.

The Sevier fault lies roughly 50 to 65 km (30 to 40 mi) eastward and subparallel to the Hurricane fault. These two features, along with the smaller Washington and Gunlock faults to the west, are considered by some to be the southern equivalent of the Wasatch Front zone of extension. Whereas long-term slip rates throughout the late Quaternary appear comparable between the two structurally aligned zones, slip rates during the Holocene are markedly different.

The Wasatch Front region has experienced a considerable increase in surface faulting during the Holocene, particularly along the central Wasatch fault zone, where slip rates have reportedly increased by a factor of ten over longer term (late Quaternary) rates.

In contrast, evidence of surface faulting along the Hurricane and Sevier faults during the Holocene in southwestern Utah is sparse.

Tectonically active regions typically have abundant active geothermal systems as fault movement fractures bedrock, thereby opening potential fluid pathways. In areas of active tectonism, meteoric water has more opportunity to circulate deep and absorb thermal energy from the surrounding rocks.