Chapter 2 lesson 1 Land formations (landforms): mountains, valleys

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Chapter 2 lesson 1
A. Land formations (landforms): mountains, valleys, hills, coastal ranges
(beaches), desserts, rivers, plateau.
B. Landforms are created by inside forces: uplifting, earthquakes, volcanoes,
magma.
C. Landforms are also created by outside forces: weathering and erosion.
2. uplift is a process that moves the surface of the earth to a higher elevation
a. Earth’s internal heat energy moves rock material and produces uplift.
b. plateau, when a large flat area is uplifted
3.Weathering uses ice to breakdown rocks.
4. surface (outside forces) process that wears away soil and rock is called
erosion
a. Erosion uses: water, wind, ice and gravity break apart the rock, changing
mountains into plains.
b. rivers and streams carry rock fragments down hill carving valleys and steep-sided
canyons.
California Landforms
1. External forces cause valleys to form
a. Glaciers carve a u shaped valley in the surface of California’s Yosemite
National park.
b. Rivers usually carve sharper, V shaped valleys in rock.
2. Internal Forces: cause volcanic eruptions that alter the landscapes by
spewing molten rock material, gas, and ash.
3. Next to the California mountain belts are flat open valleys
a. Water transports eroded material down from mountains to make the
fertile soil of California great central valley.
b. Rivers carve deep narrow valleys as they flow from the sierra Nevada
toward the Pacific Ocean.
4. Sand-sized grains of rocks from the mountains from beaches along the Pacific
Coast.
a. Ocean currents moving parallel to the shore wash away sand.
b. Beaches are temporary features that must be added sediment added
constantly for them to exist.
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