Travel Reference
In-Depth Information
majestic, towering formations like the Great White Throne at Zion, to the delicately
carved and whimsical hoodoos at Bryce Canyon. For these we can thank the geo-
logic processes of uplifting and erosion.
The parks are located on the northwestern edge of the Colorado Plateau, a
130,000-square-mile region that covers the Four Corners area and encompasses
about half of Utah, most of northern Arizona (including the Grand Canyon), much
of western Colorado, and the northwest corner of New Mexico. Named for the Col-
orado River, which is responsible for carving many of the area's scenic canyons, the
Colorado Plateau began as the result of uplifting 10 to 15 million years ago. Large,
flat beds of sedimentary rock created from different minerals—or combinations of
minerals—resulted in layers of varying densities. Forces within the earth pushed
some of these sections of sediment up out of the earth. This uplift is especially no-
ticeable in places such as Zion and Bryce Canyon. Here, uplifts along geologic fault
lines created high plateaus with large chunks of rock, where you can see the stripes
of the different layers of rock.
When wind and water began their inevitable erosion, layers of softer rock, such
as sandstone and limestone, wore down faster than the harder layers of mudstone
and shale. This created intricate and sometimes bizarre shapes. For example, the
formation called
Thor'sHammer,
in Bryce Canyon, owes its hammerlike shape to
a variety of rock densities—the hammer section on top is harder and more resistant
to erosion than the softer handle section below. Eventually, the handle will crumble
and the hammerhead will come crashing to the ground. Erosion, as well as the
shifting and breaking of rock, carved the sculptures of Zion and Bryce Canyon. The
process almost always involves water and gravity, although wind and temperature,
primarily freezing and thawing, play an important role as well.
Although there are also hoodoos similar to Thor's Hammer in Zion—mostly on
the park's east side—many of Zion's rock formations appear more massive and
rugged. But here, too, the rocks have been carved by the forces of nature, primar-
ily water, as can be seen clearly when looking up from the bottom of the
Narrows.
This incredibly slim canyon—1,000 feet high but less than 30 feet wide in some
places—was meticulously carved through Navajo sandstone by the North Fork of
the Virgin River.
How Nature
paints
the Parks
The shapes are fantastic—towering monoliths, massive mesas of stone, delicate spires, intricately
carved sculptures, and squat little toadstools—but what first catches our eyes are the delightful
colors. What seems like an infinite variety of hues elevates these parks from geologic wonders to
