Transcript 13a.1 4.1
Do Now
What are two types of geologic processes that formed the major features of the California landscape?
What is the difference between renewable and nonrenewable resources?
Do Now
What are two types of geologic processes that formed the major features of the California landscape?
Tectonic Processes – beneath the surface Agents of Erosion – on the surface What is the difference between renewable and nonrenewable resources?
Renewable Resources – can be replenished over a fairly short time – months, years or decades
Nonrenewable Resources – cannot be easily replenished over a short time – millions of years
Key Words
Interactions
Landscape
Industrial Geologic Fertile Fossil Fuel Accumulate
Vocab Words
Geothermal Field Reservoir Rocks Source Rocks
Geology of California
• Each of California’s
regions is defined by the major geologic features within that region.
• Some of the features of
our landscape was formed as the result of tectonic processes that took place deep beneath the surface.
•Wind, water, ice and
other agents of erosion at the surface carved other features of the landscape
Geologic Processes Inside Earth Forming our Mountains
Millions of years ago, the subduction of an oceanic plate beneath the North American formed large masses of igneous rock.
Uplift and erosion eventually exposed these rocks, which now form the Sierra Nevada Mountain Range.
Forming our Volcanic Mountains
Subduction of the Juan de Fuca plate beneath the North American plate produced the volcanoes in the Cascade Range.
The coast ranges are also a result of these plates moving, when large slabs of crust were accreted on the North American plate.
The San Andreas Fault was formed by the uplifted mountains.
The Central Valley and the Basin and Range regions were formed as portions of the crust dropped down.
Surface Geologic Processes
Erosion helped shaped the surface of California
Water: Mountains, hillsides and river valleys
Glacial Ice: Carved mountain peaks and vast U-shaped valleys.
Deposition of Sediment: Mojave Desert and the Central Valley
California’s Mineral Resources
Include: Sand, Gravel, Crushed Stone, Building Stone, Gold, Silver, Iron, Evaporite Minerals, and Clay
Evaporite Minerals are minerals formed as a solution containing dissolved salt evaporates.
Industrial, Metallic, Nonmetallic and Gemstones
Industrial Minerals
Sand and Gravel are California’s most valuable industrial minerals.
Another important mineral is crushed stone, mainly limestone. It is used to make cement.
Most of Granite comes from Sierra Nevadas.
Metallic Minerals
Gold, Silver and Iron are the major metallic minerals mined in California.
Most productive gold mining areas in California today include the Sierra Nevada, the Klamath Mountains and the Mojave Desert.
Silver is mined in the Sierra Nevada range.
Iron is mined in the Mojave Desert region.
Nonmetallic Minerals
Three most significant are borates, gypsum, and clay. Mostly used in building.
Borates: fiberglass, detergents, glass, ceramics, and insulation.
Gypsum: wallboard, plaster and cement.
Clay: ceramics and bricks
Gemstones
Tourmaline, Garnet, Agate, and Jade.
State Gem: Benitoite found in the Diablo Range in San Benito County.
California’s Energy Resources
Oil, Natural Gas and Geothermal Energy
Oil: Rock in which the oil forms are called source rocks, mostly shale. Oil migrates from the source rocks into nearby porous rocks called reservoir rocks and becomes trapped.
Natural Gas: Forms along with oil and is mixture of several gases, including methane. Used for gas in houses.
Geothermal Energy: Magma close to surface heats groundwater, steam is trapped and used as energy. San Bernardino runs off geothermal energy.
California’s Soil Resources
Include the soils of the Sierra, Coast Ranges/Cascades, Central Valley soils and desert soils.
Most fertile are in the central valley, where most agriculture occur.
Lowest in nutrients are in the desert regions.
Coastal regions are wetter but nutrients are washed away from all the moisture.
If we don’t conserve our soil we will lose agriculture which is a big money maker for California.
Nonrenewable vs. Renewable
Renewable resources can be replenished over fairly short spans of time, such as months, years, or decades.
Nonrenewable resources take millions of years to form and accumulate.
Fossil Fuels
Fossil fuels are hydrocarbons that may be used as fuel, including coal, oil, and natural gas.
Fuels derived from tar sand and oils shales could become good substitutes for dwindling petroleum supplies.
Group Challenge Questions
You are a farmer planning to buy some farm land. You have a choice of two available farms, one in a wide valley and the other on the side of a steep mountain slope. Which would probably be better for growing crops? Explain.
Some people predict that tar sands and oil shale will one day supply much of our energy needs. Are tar sands and oil shale a good long-term energy solution? Explain.