For over 50 years, William Stokes has been a steady contributor to the mapping and interpretation of Utah geology. This book is a late dividend of a long professional career that has been almost exclusively invested in Utah and its neighboring states. Through this book, Utahns have a unique opportunity to appreciate their geologic heritage. An unusually large segment of earth's history is recorded in over 250 formations that crop out in different areas of the state and virtually every geologic influence that shaped the earth - lakes, glaciers, wind, igneous action, tectonic forces, and erosion have left unmistakable impressions. Utah's economy is more closely linked to geology than most other states. In the past, the state relied upon the mining and energy industries and now tourism, based mainly on geologic attractions, is a major source of income. Also, the design and construction of nearly every major structure in Utah should consider geology because few other states have Utah's vulnerability to the geologic hazards associated with earthquakes, landslides, rockfalls, unstable soil conditions, high ground water, floods, liquefaction, and shifting lakes.
Probably no area of similar size in the U.S. displaces more of the raw, unobscured rock formations than does Utah. Due to the scarcity of soil, not only do rock formations appear with unobscured clarity, they also occur in great variety. Over 500 have been recognized including igneous, metamorphic, and sedimentary units of all types. The age ranges from ancient Precambrian (2 billion +), to the sands dunes still creeping across today's desert landscape. Every system of the well-known geologic column is represented, some almost completely. Each system also contains diagnostic fossils and distinctive rock types, which few other states can claim.