Credit: National Parks Service
1. The Colorado Plateau is a geological wonderland that encompasses 130,000 square miles (337,000 square kilometers) centered around the Four Corners area of the American West and within the states of Colorado, New Mexico, Arizona and Utah. It ranges in elevation from slightly over 2000 along the Colorado River in the Grand Canyon to over 12,000 feet in the Henry and La Sal Mountains of southeastern Utah. Over 90% of the plateau lands are drained by the Colorado River and its major tributaries – the Little Colorado, the San Juan and the Green Rivers.
Credit: Linda & Dr. Dick Buscher
2. This land is characterized by high mountains, rugged, eroded plateaus, river gorges, volcanic peaks, sandstone arches, spires and hoodoos and includes the splendor of the Grand Canyon. It is the most untamed landscape of the lower forty-eight states of the United States. It is home to the largest cluster of national parks (10) and national monuments (17) found anywhere in the world. Ten Native American tribes claim the Colorado Plateau as their homeland and share the arid region with a multitude of unique and scarce high desert plants and animals.
Credit: Linda & Dr. Dick Buscher
3. The Colorado Plateau is extremely old – at least 500 million years and possibly older. It is a well-defined, thick mass of continental crust that has remained intact and avoided the common rock reformation (folding and faulting). While the Western lands surrounding it were being broken and bent, stretched and uplifted, the Colorado Plateau amazingly remained unbroken.
Credit: Linda & Dr. Dick Buscher
4. The western boundary of the Colorado Plateau is marked by a large transition zone of common plateau geology and common Basin and Range Provinces. The northern boundary ends at the Uinta Mountains of Utah and the Rocky Mountains of Colorado. The Rio Grande Rift Valley of New Mexico, shown above in the Rio Grande Gorge, defines the eastern boundary and the Mogollon Rim of central and eastern Arizona marks the southern boundary. At the margins of the Colorado Plateau major ancient volcanic fields are found.
Credit: Linda & Dr. Dick Buscher
5. The Colorado Plateau has been divided into six, contrasting sections. The Datil section is located in eastern Arizona and western New Mexico and is mainly volcanic in origin. Here is found the Springerville Volcanic Field, an area of 1,158 square miles with over 400 dormant volcanic vents. The Springerville Volcanic Field, shown above, is 3rd largest volcanic field in the continental United States.
Credit: Linda & Dr. Dick Buscher
6. The Grand Canyon section is located in the southwestern and western edge of the Colorado Plateau. It is home to the magnificent Grand Canyon. Along the southeastern part of this section is found the San Francisco Volcanic Field, the largest volcanic field in the continental United States with over 600 ancient volcanic vents. The last volcanic eruption in this field occurred in CE 1064-1065 at Sunset Crater, near Flagstaff, Arizona.
Credit: Linda & Dr. Dick Buscher
7. The High Plateau section is located along the western and northwestern part of the Colorado Plateau. It is characterized by large plateaus separated by local faults. This section is home to the incredible geological formations of Zion and Bryce National Parks. Picture above shows a hiking trail passing through Bryce Canyon.
Credit: Jessi Brunson/US Fish & Wildlife Service
8. The Uinta Basin is found in the northern most part of the Colorado Plateau and is the lowest part of the great plateau. Many of the smaller tributaries of the Green River have their origin here in the Uinta Mountains. The great Spanish explorer, Father Silvestre Velez de Escalante, first visited this area in September 1776. Photo above is of the rare and endangered Barneby Ridge Cress (Lepidium barnebyanum) found only in the Uinta Basin.
Credit: Linda & Dr. Dick Buscher
9. The Canyonlands section is located in the northeastern part of the Colorado Plateau and is home to deeply cut canyons in a high desert environment. The landscape has been shaped and carved by the drainage systems of both the Green and Colorado Rivers. This is a land of spectacular vistas and home to both Canyonlands and Arches National Park. Photo is of the formation known as Double Arch found in Arches National Park, Utah.
Credit: Linda & Dr. Dick Buscher
10. The Navajo section of the Colorado Plateau is home to the Four Corners area of the American Southwest. It is the central area of the Colorado Plateau with landscapes of high plateaus separated by arid, high desert valleys. Many national monuments like Canyon de Chelley and Navajo Tribal Parks like Lake Powell and Monument Valley, shown above, are located in this dramatic section of the Colorado Plateau.
Credit: Linda & Dr. Dick Buscher
11. Because of the eroding effect of the rivers that crisscross the Colorado Plateau, the many deep canyons found here are like an open textbook of geological time. Precambrian metamorphosed gneiss and schist lie exposed at the bottom of the Grand Canyon and whose ages are thought to be over 1600 million years. The brilliant colors of the thick layers of sandstone and limestone sedimentary rocks resulted from the 380 – 145 million year old ancient seas of the Permian. Triassic and Jurassic Periods and now sit atop the many sculptured plateaus and vast plains seen today.
Credit: Linda & Dr. Dick Buscher
12. The arid climate of the Colorado Plateau is the result of a rain shadow caused by the Sierra Nevada Mountains located to the west of the plateau. Average annual precipitation of rain and snow ranges from 6 to 16 inches (15 – 40 cm). In the higher elevations more precipitation occurs and results in forests of pine, spruce and fir.
Credit: Linda & Dr. Dick Buscher
13. The Colorado Plateau is a region of great ecological diversity. From thick riparian river banks lined with forests of cottonwood trees to miles and miles of dry desert basins covered with saltbush and greasewood; from grass covered mountain meadows to ponderosa pine covered mountain peaks – all varieties of nature’s botanical species are represented in this rugged, untamed wilderness. During late spring and early summer wildflowers abound all across the plateau.
Credit: Linda & Dr. Dick Buscher
14. The wildlife of the Colorado Plateau is as diverse as the landforms, vegetation and the climate. Collared lizards, elk, rattlesnakes, cougars, bobcats, jackrabbits, mule deer and more all roam across the land seeking to survive in this harsh environment. This collared lizard, shown here, is enjoying the springtime sun at Arches National Park.
Credit: Linda Buscher
15. A vast variety of birds fill the sky over the Colorado Plateau. Stellar jays, wild turkeys, various species of hawks and falcons are found here. Many migratory songbirds move across the Colorado Plateau each spring and fall. The Colorado Plateau is once again home to California condors that now again soar above the deep chasms of the Grand Canyon thanks to the successful efforts of a condor reintroduction program near the Vermillion Cliffs of northern Arizona.
Credit: Linda & Dr. Dick Buscher
16. American author and environmentalist Edward Abbey when asked about the uniqueness of the Colorado Plateau, stated that "there is no other region on earth much like it, or even remotely like it ... this is a landscape that has to be seen to be believed, and even then, when confronted directly by the senses, it strains credulity."
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