The Geologic Map of the St. George 7.5’ Quadrangle covers approximately 50 square-miles of land in and around the City of St.George, extending south to the Arizona border. The Geologic Map of the White Hills Quadrangle covers 50 square miles immediately west of the St. George map and includes the suburb of Bloomington and the upper reaches of the Virgin River Gorge.
Colorful 300 to 190 million-year-old sedimentary rocks, black 2.3 million to 33,000 year-old-basaltic lava flows and modern unconsolidated sediments are exposed across the mapped areas. The maps
show locations of rock formations that are prone to landslides and rocks falls, produce collapsible and expansive problem soils, emit radon, as well as those that commonly yield geologic resources such as flagstone, gravel, and gypsum. gas exploration efforts and potentially active earthquake faults.
The Geologic Map of the St. George 7.5’ Quadrangle, Washington County, Utah (Map 251DM) and the Geologic Map of the White Hills Quadrangle, Washington County, Utah (Map DM250) can be viewed on the UGS website at Geology.Utah Online.
They are also available as either a printed map for $14.95 or on a DVD (contains GIS database and pdf of map) for $24.95 at the Utah Natural Resources Map & Bookstore, 1594 West North Temple, Salt Lake City, Utah - or, call (801) 537-3320.
The Utah Geological Survey provides timely scientific information about Utah’s geologic environment, resources, and hazards.


