HERE IS TRULY A LIVING WILDERNESS nurtured by the
ocean! The Olympic Mountains stand first in line against the moisture-filled
Pacific winds. These winds, rising and cooling on the western slopes,
drop 12 to 18 feet of rain and snow on forest and mountains each year. Two
extraordinary conditions resulta temperate-climate rain forest and an
abundance of permanent ice bodies at comparatively low altitudes. Many
rushing streams return the water from snowfields, glaciers, and forest
slopes to the sea. A complete and endless circuit of water from ocean
to land and back to the ocean may be observed from a single mountain
vantage point. One can hardly fail to notice a water cycle of this
magnitude and completeness or to appreciate its great influence on the
Olympic scene.
Olympic rocks tell of their having been formed of
mud, sand, and lava, uplifted from the sea; they tell of earth
disturbance that alternately submerged the land beneath the sea and
elevated it into mountains. The rocks and the shape of the land also
tell of colder climates, when ice from the north made almost a glacier
island of the Olympic Mountains, and of mountain valley glaciers which
sculptured the mountains during thousands of years. The rugged beauty of
the Olympic high country, enhanced by scores of mountain lakes, bears
testimony to the former presence of these extensive glaciers.
Only about 11,000 years have passed since the last
wave of northern ice retreated and laid bare Olympic rocks. Since then
the moist and gentle climate has favored the growth of plants and the
development of soil. The present Olympic forests and flowering meadows
are products of a succession of plantlife from the first lichens and
mosses that grew on Olympic rocks. Animals returned when the ice
retreated. Plant eaters and meat eaters, large and small, throve in
abundance. When primitive man came, he found the land and sea kindly. He
easily obtained what he needed for food, clothing, and shelter without
depleting the supply.
While most of the Northwest was being explored and
settled by the white man during the 19th century, the bulk of the
Olympic Peninsula remained virtually unknown. Its rugged mountains,
dense forests, and isolation contributed to the delayed advance of
modern civilization to this northwesternmost corner of conterminous
United States. The Olympic Peninsula thus remained one of the last
frontiers, and the park retains genuine wilderness quality, even to its
boundaries which descend to sea level.
In this piece of original America the perceptive eye
and mind will find a functioning model of naturea model of
earth forces, climate, and life.
The Mountains Are Formed
The present Olympic Mountains were born between 12
and 20 million years ago when western Washington was pushed up into a
great range that extended from Cape Flattery southeastward to the
eastern part of the State. At the same time, the land to the north and
south was depressed and remains depressed today as Juan de Fuca Strait
and Chehalis Valley, respectively. The Olympics were further elevated
about 5 million years ago. This coincided with the building of the
Cascade Mountains and the down-folding of the land between to form the
Puget Sound trough. The Olympics were now isolated, having lowland on
all sides.
Olympic rocks formed in shallow seas that at least
five times have covered western Washington. Sediments washed from
adjacent land areas and accumulated on the sea bottom. Muds became
shales and sands were cemented into sandstones. Molten lava
erupted through these beds and was quickly cooled by the water.
Thousands of feet of rock material formed in this way.
When earth forces lifted the sea floor, the sea
disappeared, and for long periods there were mountains where the sea had
been.
Pressure and heat changed the rocks, especially the
sedimentary rocks, which became harder and tougher. Shale changed
progressively into slate and phyllite. All of these rocks are found in
the Olympic Mountains. The sedimentary rocks and lava flows, originally
horizontal on the sea floor, were tilted and folded when uplifted and
this is how we see them today.
Long periods of erosion have removed thousands of
feet of rock and remolded the Olympics into magnificently rugged
mountains. Thus, earth forces build mountains and water slowly carries
them back to the sea. So it has been since the first rains fell upon the
cooling earth.
Today only the oldest rocks remain, for these were
the bottom layers. The greater part of the Olympic Mountains are made up
of these rocks, now mostly slates and hardened sandstones. This includes
all the rock inside a horseshoe-shaped line running from the village of
Sappho east to Lake Crescent, Lake Mills, and Deer Park, then south to
the west side of Mount Constance and the north end of Lake Cushman and
then west to Lake Quinault. The horseshoe-shaped rim of the mountains
outside this line is mostly basaltic lava.
Because fossils are scarce in the oldest rocks,
geologists are not certain about their age, but they are thought to be
about 120 million years old. The rocks in the outer rim of the Olympic
Mountains contain more fossils. These have been found in the sandstones,
shales, and limestones interbedded with the thick volcanic rocks. Fish
teeth, marine clams, snails, algae, wood fragments, and microscopic
shells found here represent forms of life that existed 50 to 60 million
years ago.
MOUNT ANGELES SHOWS TILTED ROCKS UPHEAVED FROM THE
SEA BOTTOM.
|
|