Download California`s Landforms

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Volcanoes
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6.4 Enrich
California’s Landforms
1. Explain how the three major landforms in northern California formed.
2. Plates separated by the San Andreas Fault move horizontally past each
other. What kind of plate boundary is the San Andreas?
3. Where is Yosemite Valley and how did it form?
4. What is happening to the Transverse Ranges?
5. Compare and contrast the Colorado and Mojave Deserts.
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Volcanoes
Many of California’s landforms are the result of plate movements. In the
northern part of the state, collision between the North American plate and
the Pacific plate resulted in the Cascade Range. These mountains include
three of the state’s active volcanoes—Mount Lassen, Mount Shasta, and
Medicine Lake. The colliding boundary also produced the Modoc Plateau, a
large, flat plateau made mainly of volcanic rocks. The Klamath Mountains
consist mostly of igneous and metamorphic rocks. They are sliced by many
active faults.
Landforms in central California include, from west to east, the Coast
Ranges, the Central Valley, the Sierra Nevada, and the Basin and Range
Province. Most of the rocks in the Coast Ranges formed as one plate was
subducted beneath another. The Coast Ranges roughly parallel the San
Andreas Fault system, another plate boundary. Many of California’s
earthquakes occur along this fault.
The Central Valley is a low-lying region that was once covered by a
shallow sea. Sediment filled the low-lying area to form one of the nation’s
richest farmlands.
East of the Central Valley is the Sierra Nevada, a mountain range that
slopes gently toward the west. This part of California formed as a batholith
was uplifted to form a mountain range that includes Mt. Whitney. During
the last ice age, glaciers shaped much of the topography of the Sierra
Nevada. One well-known result of the work of glaciers is Yosemite Valley.
The Basin and Range region lies to the east of the Sierra Nevada. The
Basin and Range is a series of basins separated by blocks of uplifted rock.
Death Valley, the lowest point in the United States, is a part of the Basin and
Range.
Landforms in southern California include the Transverse Ranges, the
Peninsular Ranges, and the Colorado and Mojave Deserts. The Transverse
Ranges are rising as plate motions compress the rocks in this part of the state.
The nearby Peninsular Ranges include peaks and valleys that are separated
by branches of the San Andreas Fault. The Colorado Desert is a low-lying
basin that was once covered by a lake. In contrast, the Mojave Desert consists
of wide plains separated by mountains.
Answer the following questions on a separate sheet of paper.