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Our dynamic planet is constantly being shaped and reshaped
by dramatic events such as earthquakes, volcanoes, and
mudslides. Other changes may not be detected in a human
lifetime. Geological time spans or Periods cover
millions of years. The Cretaceous Period began
some 144 million years ago and lasted until about 63 million
years ago. The rock formations you see exposed at Bryce
Canyon began to develop during this time. For 60 million
years a great seaway extended northwestward into this
area, depositing sediments of varying thickness and composition
as it repeatedly invaded, retreated, then re-invaded the
region. Retreating to the southeast, it left sediments
thousands of feet thick. Their remnants form the oldest,
lowest, gray-brown rocks at Bryce Canyon.
In the Tertiary Period, between
66 and 40 million years ago, highlands to the west eroded
into shallow, broad basins. Iron-rich, limy sediments
were deposited in the beds of a series of lakes and streams.
These became the reddish rocks of the Claron Formation
from which the hoodoos are carved and for which the Pink
Cliffs are named.
The Cretaceous Seaway moved northward
from the Gulf of Mexico into this region of North America.
Sediments deposited as the sea invaded and retreated became
the brown and gray marine rocks now exposed at the park's
lowest elevations and across the Paria Valley.
Deformation,
Uplift, and the Grand Staircase
Horizontal compression related to the formation of the
Rocky Mountains deformed these rocks. Then volcanic flows
from the north covered parts of the region: black rocks
at the mouth of nearby Red Canyon and on the Sevier
Plateau to the north still protect softer underlying
layers. About 10 million years ago the Earth pulled apart,
moving and tilting great blocks along north-south trending
fault lines. Layers, once connected, were displaced vertically
by several thousand feet, forming the High Plateaus of
Utah.
Older Cretaceous layers rested side by
side with younger Tertiary layers across fault lines.
Streams began to remove sediments deposited by their ancestors.
Working on the weakened edges of the upthrown blocks,
water gradually removed the uppermost Tertiary layers
and exposed Cretaceous rocks once again. Now these drab
former marine sediments lay on the surface of the land
side by side with the brightly colored deposits of freshwater
lakes and streams.
Differential
Erosion
Water erodes rock mechanically and chemically. Scouring,
abrading, and gullying occur when fast-moving water scrapes
its silt, gravel, and rock debris against firmer bedrock.
Slow-moving or standing water enters minute rock pores
and dissolves cements holding the rock together. This
leaves loose grains to wash away. Softer Cretaceous rocks
were loosened and carried away from the upthrown block
by the Paria River. The resulting Paria Valley is carved
out of rocks that lie deep beneath the Paunsaugunt Plateau,
whose edge now is exposed to erosion.
Along the plateau rim, conditions are
optimal for erosion. Its steep slope increases water speed
and energy. Faults and joints from ancient compressional
forces influence erosion patterns. Freezing and thawing
loosen slope surfaces. Debris carried by runoff, scours
softer rock and creates gullies; harder rock remains as
fins.
As gullies widen to canyons, fins
become exposed to further erosion along vertical cracks.
In winter, freezing water expands within cracks to peel
off layers and carve vertical columns.
Hoodoos Cast
Their Spell
Hoodoo - a pillar of rock, usually of fantastic
shape, left by erosion.
Hoodoo - to cast a spell.
At
Bryce Canyon National Park erosion forms a remarkable
array of fantastic shapes we know as hoodoos. Surrounded
by the beauty of southern Utah, these hoodoos cast their
spell on all who visit. Geologists say that ten million
years ago forces within the Earth created and then moved
the massive blocks we know as the Aquarius and
Paunsaugunt plateaus. Rock layers on the Aquarius
now tower 2,000 feet above the same layers on the Paunsaugunt.
Ancient rivers carved the tops and exposed edges of these
blocks, removing some layers and sculpting intricate formations
in others. The Paria Valley was created and later widened
between the plateaus.
The Paria River and its many tributaries
continue to carve the plateau edges. Rushing waters carrying
dirt and gravel gully the edges and steep slopes of the
Paunsaugunt Plateau on which Bryce Canyon National Park
lies. With time, tall thin ridges called fins emerge.
Fins further erode into pinnacles and spires
called hoodoos. These in turn weaken and fall,
adding their bright colors to the hills below.
Early Native Americans left little to
tell us of their use of the plateaus. We know that people
have been in the Colorado Plateau region for about 12,000
years, but only random fragments of worked stone tell
of their presence near Bryce Canyon. Artifacts tell a
more detailed story of use at lower elevations beyond
the park's boundary. Both Anasazi and Fremont
influences are found near the park. The people of each
culture left bits of a puzzle to be pieced together by
present and future archaeologists. Paiutes lived in the
region when Euro-Americans arrived in southern Utah. Paiutes
explained the colorful hoodoos as "Legend People"
who were turned to stone by Coyote.
The Paiutes were living throughout the
area when Capt. Clarence E. Dutton explored here
with John Wesley Powell in the 1870s. Many of today's
place names come from this time. Dutton's report gave
the name Pink Cliffs to the Claron Formation.
Other names Paunsaugunt, place or home of
the beavers; Paria, muddy water or elk water; Panguitch,
water or fish; and Yovimpa, point of pines
were derived from the Paiute language.
The Paiutes were displaced by emissaries
of the LDS Church who developed the many small communities
throughout Utah. Ebenezer Bryce aided in the settlement
of southwestern Utah and northern Arizona. In 1875 he
came to the Paria Valley to live and harvest timber from
the plateau. Neighbors called the canyon behind his home
Bryce's Canyon. Today it remains the name not only
of one canyon but also of a national park.
Shortly after 1900, visitors were coming
to see the colorful geologic sights, and the first Hotels - Motels
were built along the Paunsaugunt Plateau rim above Bryce's
Canyon. By 1920 efforts were started to set aside these
scenic wonders. In 1923 President Warren G. Harding proclaimed
part of the area as Bryce Canyon National Monument under
the Powell (now Dixie) National Forest. In 1924 legislation
was passed to establish the area as Utah National Park,
but the provisions of this legislation were not met until
1928. Legislation was passed that year to change the name
of the new park to Bryce Canyon National Park.
Each year the park is visited by more
than 1.5 million visitors from all over the world. Languages
as varied as the shapes and colors of the hoodoos express
pleasure in the sights. Open all year, the park offers
recreational opportunities in each season. Hiking, sightseeing,
and photography are the most popular summer activities.
Spring and fall months offer greater solitude. In the
winter months, quiet combines with the area's best air
quality for unparalleled views and serenity beyond compare.
In all seasons fantastic shapes cast their spell to remind
us of what we protect here in Bryce Canyon National Park.
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