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Whaleskin crossbedding patterns, Navajo Sandstone narrows, Grand Staircase Escalante National Monument, Utah. Phot © 1996 Ray Wheeler. |
The land surface holds more recent geologic history frozen in stone. There are petrified sand dunes and ripple marks, inverted valleys, entrenched river meanders, and whole forests of petrified trees. Asked by the National Park Service to identify potential "Natural Landmarks" on the Colorado Plateau, two teams of geologists dashed into the field like starving children let loose in a candy store, and returned with a list of no fewer than 110 sites which deserve national recognition as classic displays of geologic phenomena. "In no other province in America," they wrote in their report, "are the relationships between morphology and geology more clearly or graphically revealed."
Consider, for example, the work of erosion. There are thousands of miles of canyons on the Colorado Plateau, and every one of those miles is a hoard of erosional sculptures. There are alcoves, grottoes, potholes, pouroffs, plunge basins, and rincons. There are windows and towers, cliff-walls riddled with honeycombing or pitted with ‘conchoidal’ fractures. Above the rims of the canyons one finds retreating cliff-walls hundreds of miles long, each leaving behind it a landscape strewn with colossal erosional remnants. There are at least 25 major plateaus, hundreds of mesas, thousands of buttes, domes, towers, monuments, temples, spires. There are whole valleys filled with stone hoodoos and goblins. Far out in the desert, one can find solitary monoliths and preposterous balanced rocks. There are thousands of natural stone arches and bridges on the Colorado Plateau, at least five with spans of more than 200 feet.
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The "Cathedrals" of Cathedral Valley, viewed from Thousand-lake Mountain near Capitol Reef National Park. Photo © 1999 Ray Wheeler. |
The Colorado Plateau harbors some of the world's most spectacular volcanic formations, including laccolithic mountain ranges, jet-black basalt "dikes" that cut across the landscape like the Great Wall of China, and expanses strewn with obsidian and volcanic bombs.
There are badlands, sand dunes, and "painted" deserts.
All this, and one thing more.
The Plateau Province is wilderness. It is one of the last and largest remnants of the American frontier, a place where even contemporary human history hangs suspended in time. Just 50 years ago Wilderness Society founder Robert Marshall identified the region surrounding the Colorado River canyons in southeastern Utah as the single largest roadless area in the coterminous United States. In all, Marshall found 20 million acres in six huge roadless areas on the Plateau. And though mineral exploration has reduced the size of those roadless areas, the region still remains one of the largest blocks of undeveloped land in the West.
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