Glacier National Park in Montana highlights landforms created by glaciers.
A landform is any natural feature on the Earth’s land surface, such as islands, bays, volcanoes and mountains. Some of the more famous landforms serve as focal points of nature preserves and parklands, such as those operated by the U.S. National Park Service. Landforms are shaped by natural forces such as volcanic eruptions, soil erosion by wind and water, and glacial movements.
The intensity of an eruption shapes a volcano.
Volcanoes are mountain peaks that contain openings from which lava, ash and other materials reach the earth’s surface. The type of eruption often determines a volcano’s landform. Shield volcanoes feature gentle slopes, especially at the top, that form from non-explosive eruptions. Composite volcanoes, or stratovolcanoes, are more explosive and have steeper slopes at the top due to thick lava flows that travel relatively short distances. Many lakes, such as southern Oregon’s Crater Lake Calderas, a water-filled craters of volcano landforms.
Erosional Coastal Landforms
Seaside cliffs are formed from waves that undercut steep slopes.
Ocean waves create coastal landforms through erosion. Cliffs result from waves that pound rocky coast lines. The undercut forms a platform, or terrace, at the foot of the cliff. Inland retreat of cliffs occurs with the wave action until the waves lose energy from having to cross the terrace. Wave-generated erosion also carves sea notches, sea caves, sea arches and sea stacks.
Cape Cod was formed from ancient glaciers.
Moving glaciers carve significant amounts of land to create steep and almost-vertical mountainsides, deep valleys, and rolling hills. Glaciers also contribute to coastal features, such as much of Cape Cod in Massachusetts. At Cape Code, a glacier migrated from southern Canada and northern New England approximately 21,000 years ago. As temperatures moderated, the glacial mass melted, raising sea levels and leaving deposits that would form the coastline and beaches of the cape.
National Parks That Feature Landforms
Crater Lake National Park features a crater-filled lake.
Many remarkable landforms have become enshrined as national parks. Yosemite National Park in Wyoming and Glacier National Park in Montana display steep mountainsides and deep valleys created by ancient glaciers. Glaciers also formed the Cape Cod National Seashore. Crater Lake National Park in Oregon features an example of a caldera, or crater-created lake.