Crater Lake in Klamath County, Oregon — The American West (Northwest)

Glacial Valleys

Crater Lake National Park

Photographed by Don Morfe, June 29, 2009

1. Left Side of the Glacial Valleys Marker

Inscription. The collapsed volcano that now holds Crater Lake once stood more than a mile (1.6 km) above the present lake level. Called Mt. Mazama, this massive mountain of overlapping cones was high enough to support a cap of snow all year. During the Ice Age, snow often blanked the entire mountain—more snow than the summer sun could melt. The accumulated snow compacted to form glaciers, sluggish rivers of ice that carved out broad valleys as they inched down the slopes.

Eventually, the ice in the valleys melted. When the top of Mt. Mazama caved in about 7,700 years ago, the upper portions of the valleys collapsed with it. Today, you can see the remains of two “U” shaped glacial valleys on the caldera wall across the lake, Kerr Notch (left) an Sun Notch (right).

Graphic Illustrations:
1. Alternating eruptions of lava and cinders built Mt. Mazama to its maximum height.

2. Glaziers formed on the upper slopes, growing larger during the Ice Age.

3. Climatic changes and more eruptions melted the glaciers, exposing the excavated valleys.

4. The collapse of Mt. Mazama truncated the glacial valleys, leaving “notches” still visible today.

Erected by National Park Service, U.S. Department of the Interior.

Topics. This historical

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marker is listed in these topic lists: Landmarks • Natural Features.

Location. 42° 54.696′ N, 122° 8.76′ W. Marker is in Crater Lake, Oregon, in Klamath County. It is on Rim Drive north of Oregon Route 62. Touch for map. Marker is in this post office area: Crater Lake OR 97604, United States of America. Touch for directions.

Regionally, this marker is in the High Desert

and in Southern Oregon.

It is also in the American Mountain West

and in the Lewis & Clark Corridor.

Globally, it is in North America,

in the Cascade Range,

on the Ring of Fire,

in the Pacific Rim,

in the Western Hemisphere,

in the Western World,

and in the Anglosphere.

Other nearby markers. At least 6 other markers are within 9 miles of this marker, measured as the crow flies: Stephen Tyng Mather (approx. 0.2 miles away); Before the Collapse (approx. ¼ mile away); After the Collapse (approx. ¼ mile away); Whitebark Pines (approx. 5.2 miles away); Ancient Spirits (approx. 5½ miles away); Pumice Desert (approx. 8.1 miles away).

Regarding Glacial Valleys. Crater Lake has long attracted the wonder and admiration of people all over the world. Its depth of 1,943 feet (592 meters) makes it the deepest lake in the United States, and the seventh deepest in the world. Its fresh water is some of the clearest found anywhere in the world. The interaction of people with this place is traceable at least as far back as the eruption of Mount Mazama. Founded May 22, 1902, Crater Lake National Park seeks to preserve these natural and cultural resources.
National

Right Side of the Glacial Valleys Marker image. Click for full size.

Photographed by Don Morfe, June 29, 2009

2. Right Side of the Glacial Valleys Marker

Photo Caption:
Further proof that glaciers blanketed the slopes of Mt. Mazama are glacial striations, grieves cut into rocks by other rocks embedded in the creeping ice.

Park Service

Wizard Island - Crater Lake National Park image. Click for full size.

Photographed by Don Morfe, June 29, 2009

3. Wizard Island - Crater Lake National Park

Crater Lake National Park image. Click for full size.

Photographed by Don Morfe, June 29, 2009

4. Crater Lake National Park

Photographed by Don Morfe, June 29, 2009

5. Crater Lake National Park

Photographed by Don Morfe, June 29, 2009

6. Crater Lake

Photographed by Don Morfe, June 29, 2009

7. Crater Lake

Photographed by Don Morfe, June 29, 2009

8. Crater Lake National Park

Photographed by Don Morfe, June 29, 2009

9. Crater Lake

National Park Passbook Cancellation Stamp. image. Click for full size.

Photographed by Don Morfe, June 29, 2009

10. National Park Passbook Cancellation Stamp.

Crater Lake National Park is named after the deepest lake in the United States. Crater Lake is world renowned for its blue color. Lying in a magnificent mountain setting, the lake fills the caldera of Mt. Mazarna, a volcano that erupted and then collapsed 6,800 years ago.

Crater Lake National Park North Entrance Sign image. Click for full size.

Photographed by Don Morfe, June 29, 2009

11. Crater Lake National Park North Entrance Sign

Glacial Valleys Marker image. Click for full size.

Photographed by Volcanoguy, November 6, 2009

12. Glacial Valleys Marker

Credits. This page was last revised on April 14, 2020. It was originally submitted on December 23, 2012, by Don Morfe of Baltimore, Maryland. This page has been viewed 685 times since then and 15 times this year. Photos: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11. submitted on December 23, 2012, by Don Morfe of Baltimore, Maryland. 12. submitted on April 14, 2020. • Syd Whittle was the editor who published this page.

Editor’s want-list for this marker. Photo showing a full view of the marker. • Wide area view of the marker and its surroundings. • Can you help?