Explore Geology
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Gates of the Arctic

National Park and Preserve


cover of park brochure

park geology subheading
Photo of Gates of the Arctic
Gates of the Arctic National Park and Preserve, Alaska

This is one of the finest remaining wildernesses in the world. The park and preserve extends nearly 320 kilometers (200 miles) from east to west, including some 5.7 million hectares (8.1 million acres) in the central Brooks Range in north central Alaska. The entire park and preserve area lies north of the Arctic Circle and is about 320 kilometers (200 miles) northwest of Fairbanks. It extends from the southern foothills of the Brooks Range across the range's ragged peaks and down onto the North Slope. Magnificent valleys dissect the range here, many containing clearwater rivers and alpine lakes. A few alpine glaciers occupy the north sides of higher mountains. Most of the park and preserve area, lying north of the limit of trees, is vegetated with shrubs and tundra.

Alaska's Ultimate Wilderness
Few landmarks are named on topographic maps here. The dramatic title for the park comes from wilderness advocate Robert Marshall, a frequent traveler in the North Fork Koyukuk drainage from 1929 to 1939. Marshall described two peaks, Frigid Crags and Boreal Mountain, as "the gates" from Alaska's central Brooks Range into the arctic regions of the far north. The natural forces of water, temperature, and glacial and tectonic action have sculpted a wildly varied landscape in this northernmost and east-west trending portion of the Rocky Mountains. Southerly foothills step into waves of mountains rising to elevations of 4,000 feet. These in turn may climax in limestone or granitic peaks over 7,000 feet.

At the Arctic Divide the ranks reverse as the tundra stretches to the Arctic Ocean. Six national wild rivers

  1. the Alatna,
  2. John,
  3. Kobuk,
  4. Noatak,
  5. North Fork Koyukuk, and
  6. the Tinayguk
are among the numberless waterways transecting the park.

The scene is one of remote wilderness and unpeopled distances, qualities many people seek when they decide to visit Gates of the Arctic. No trails or visitor service developments exist within the park. All visitors must be self-sufficient. One Nunamiut Eskimo village, Anaktuvuk Pass, lies within the park's boundaries. In the past, nomadic hunters/gatherers traveled from the forested southern slopes of the mountains to the Arctic Coast. Present-day travelers will see few signs of earlier inhabitants. Perpetuation of wilderness qualities is a primary goal of the park's management.

Seasons are dramatic in length and levels of activity: during the short summer, plants and animals must progress rapidly through growth and reproduction cycles before the onset of winter cold. Most activity ceases with the-20°F to-50°F temperatures that persist from November to March. In the pink, low light of the arctic winter, blue-gray shadows of opposing slopes delineate the endless white mountains. The dry climate of the interior produces little snow, but what falls endures and covers the land and rivers wrapped in ice and silence. As the low-riding sun begins its warming ascent into April's spring sky, dog sled enthusiasts occasionally may be seen in the park. Other visitors begin arriving in mid-June, although many rivers are of yet entirely free of ice. Backpacking and river trips are the predominant activities.

The park, created to ensure the integrity of the arctic environment, contains major portions of the range and habitat of the western arctic caribou herd. Grizzly and black bear, wolf, moose, Dall sheep, wolverine, and fox are also found in the park. At spring breakup, the few resident bird species are joined by migratory species from Europe, South America, Asia, tropical archipelagos, and the continental United States. Despite the variety, wildlife is widely dispersed because large areas are required to sustain life in the Arctic. Wildlife sightings may be greatly affected by the size of your party, your patterns of travel, and the weather.

Sparse black-spruce forests called taiga-from the Russian for "land of little sticks"-dot north-facing slopes and poorly drained lowlands. Boreal forests of white spruce, aspen, and birch are typically found on south-facing slopes. Near tree line, the shrub-thicket community of dwarf and resin birch, alder, and willow appears. Heath, moss, and fragile lichen make up the understory. Alpine tundra communities occur in mountainous areas and along well-drained rocky ridges. Alder thickets and tussocks often impede hiking in the Arctic. Backpackers will find both types of vegetation in valleys and on slopes; it is not unusual for backpackers to progress only 5 miles per day. Take your time: do not try to squeeze a 21-day arctic trip into a 14-day "Lower 48" trip.

The 1980 legislation which created Gates of the Arctic National Park and Preserve called for protection of 8.4 million acres of land. Included were mandates for insuring that the area be managed to maintain the land's wild and undeveloped character. Far-sighted provisions also included opportunities to experience solitude, to insure the environmental integrity of natural features, and to provide opportunities for wilderness recreational activities. Fish and wildlife and their habitat, cultural resources, and traditional subsistence uses were also slated for protection. With adjacent Noatak National Preserve and Kobuk Valley National Park, Gates of the Arctic comprises one of the world's largest parkland areas.

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 geology photo album has not been prepared for this park.

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

Currently, we do not have a listing for any park-specific geology education programs or activities.

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/gaar/index.cfm   I  Email: Webmaster
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