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Mount Rainier

National Park


cover of park brochure

park geology subheading
Visitors on bridge with Mount Rainier in the background
Mount Rainier National Park, Washington

Welcome to a mountain wonderland of dense forests, dazzling wildflowers, tremendous snowfields, and rugged glaciers. Enjoy the fresh smell of trees and soil, the soothing - and sometimes deafening - sound of falling water, and the refreshing cold breezes off the glaciers. And towering above all this scenic display is magnificent Mount Rainier

This is a complex landscape, but the explanation of its origins are simplicity itself: fire and ice. The mountain is a volcano born of fire and built up above the surrounding country by repeated eruptions and successive flows of lava. It is a relatively young volcano, only about one million years old. By contrast the mountains of the Cascade Range that Mount Rainier looks down upon are at least 12 million years old, created by the folding, buckling, and uplifting of the Earth's surface. Mount Rainier is not an isolated volcano, for from Lassen Peak in California to Mount Garibaldi in British Columbia an entire line of volcanoes defines the north-south march of the Cascades. These peaks dominate the skyline, ever a reminder that they are only dormant and may at any time, like Lassen Peak in 1914-21, and Mount Saint Helens in 1980, erupt in fury and rage at the fragile world built by humans. One of the unexpected side benefits of these eruptions has been the deposition of ash and pumice layers that are rich in nutrients and support the abundance of wildflowers throughout the mountainous Pacific Northwest.

Even as volcanic forces were building up this land, the slow, inevitable power of glacial ice began to shape and form it. Glaciers come from the snow that does not melt from year to year: it accumulates to greater and greater depths. The weight of the snow presses the air out, packs it down tight, and compresses it into ice. Gravity pulls the ice down the mountainside, both scouring and smoothing the bedrock as it goes. Freezing and thawing breaks rocks from the adjacent slopes, and they fall onto the glacier's surface. More debris is picked up by the passing ice. This is an inexorable process that continues today and will alter the mountain in the tomorrows to come. Yes, the process is simple, but it deals in forces that are beyond the control, and perhaps comprehension, of humans. Take a look at this mountain; it may be gone in a million years.

Geologic History
The volcanoes in the north- south trending Cascade Province evolved through a history of complex plate tectonic processes and glaciation. Different tectonic models have been proposed for the development of the Cascades, but all models include subduction, addition of exotic terranes, and oblique plate movements as important components in creating today’s . . . read more

Geologic Setting
Towering 1.5 miles (2.4 km) above the surrounding mountains and about 3 miles (5 km) above the lowlands to the west, Mount Rainier is the second highest peak in the conterminous United States at 14,410 ft . . . read more

Geologic Features & Processes
Glaciers are highly effective erosional agents, shaping mountains into picturesque landforms with such distinctive erosional features as horns (peaks), cirques (deep, bowl- shaped, steep- walled recesses in a mountain), glacial valleys (U- shaped valleys), and arêtes . . . read more

park maps subheading

The General park map handed out at the visitor center is available on the park's map webpage.

For information about topographic maps, geologic maps, and geologic data sets, please see the geologic maps page.

photo album subheading

A general photo album for this park can be found here.

For information on other photo collections featuring National Park geology, please see the Image Sources page.

books, videos, cds subheading

Currently, we do not have a listing for a park-specific geoscience book. The park's geology may be described in regional or state geology texts.

Please visit the Geology Books and Media webpage for additional sources such as text books, theme books, CD ROMs, and technical reports.

Parks and Plates: The Geology of Our National Parks, Monuments & Seashores.
Lillie, Robert J., 2005.
W.W. Norton and Company.
ISBN 0-393-92407-6
9" x 10.75", paperback, 550 pages, full color throughout

The spectacular geology in our national parks provides the answers to many questions about the Earth. The answers can be appreciated through plate tectonics, an exciting way to understand the ongoing natural processes that sculpt our landscape. Parks and Plates is a visual and scientific voyage of discovery!

Ordering from your National Park Cooperative Associations' bookstores helps to support programs in the parks. Please visit the bookstore locator for park books and much more.

geologic research subheading

For information about permits that are required for conducting geologic research activities in National Parks, see the Permits Information page.

The NPS maintains a searchable data base of research needs that have been identified by parks.

A bibliography of geologic references is being prepared for each park through the Geologic Resources Evaluation Program (GRE). Please see the GRE website for more information and contacts.

selected links subheading

NPS Geology and Soils Partners

NRCS logoAssociation of American State Geologists
NRCS logoGeological Society of America
NRCS logoNatural Resource Conservation Service - Soils
USGS logo U.S. Geological Survey

teacher feature subheading

General information about the park's education and intrepretive programs is available on the park's education webpage.

For resources and information on teaching geology using National Park examples, see the Students & Teachers pages.
updated on 01/04/2005  I   http://www.nature.nps.gov/geology/parks/mora/index.cfm   I  Email: Webmaster
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