California Geology

Geology of California Plate tectonics responsible for a lot of features –Sierra Nevadas formed by subduction –Volcanoes of Cascade Range = subduction –Coast Ranges = plates moving together –San Andreas Fault –Central Valley = faults causing crust to drop

Mineral Resources Mineral resources = minerals, rocks, sediment, and products made from these What are California’s major mineral resources? –Sand, gravel, crushed stone, building stone, gold, silver, iron, clay What are some ways we use these mineral resources everyday?

Minerals Industrial minerals –Sand and gravel –Crushed stone – mostly used to make cement Metallic minerals –Gold and silver –Iron Nonmetallic minerals –Borates – used in fiberglass, detergents, glass, ceramics, and insulation –Gypsum – wallboard, plaster, cement –Clay – ceramics and bricks

Energy Resources CA is a leading producer of energy resources Major energy resources? –Oil, natural gas, geothermal energy –All occur as result of geologic processes deep below the earth

Oil 15% produced in US comes from CA Oil formed from tiny organisms that died and were buried deep in ocean floor –Trapped in reservoir rocks –Wells drill into these rocks Found in 18 of 58 counties, both on land and off-shore

Natural Gas Mixture of several gases Less dense, found at top of reservoir Used for heating, cooking, and to generate electricity

Geothermal energy Leading state in geothermal energy…Why? –Active geology/plate tectonics below the state Geothermal fields = area where magma close to the surface heats the water –Drill wells –Tap into steam in rock –Steam powers turbines that produce electricity

Soil Resources Fertile Valley Soils most important Napa Valley soils – Good for growing grapes Central Valley – Once grassland – Fertile due to floodplains

California’s Water Supply Main sources?... Precipitation, groundwater, and surface water Precipitation –Only 35% stays at surface or seeps into ground –Avg. of 58 cm. per year –Most in Northern California and the mts. Surface water –Drainage in Northern California provides ½ water needed –Colorado River major source of freshwater

Water Supply Groundwater –30% of water used in California Desalination –Removal of salt from ocean water –Expensive but important

Water Projects Local –Aqueducts – long pipes or channels where water flows from higher to lower elevation –North = melted snow –South = Colorado and Owens Rivers State –Reservoirs, pumping plants, canals, and pipelines –Supplies water for crops in San Joaquin Valley

Water Needs Where does California use it’s water? –80% used for agriculture –Houses/Business = avg. of 380 liters/person/day! –Industry – mostly used as a coolant –Recreation/Wildlife

California’s Natural Hazards Natural hazard = event that results from Earth processes and can cause damage or endanger human life With that definition in mind, what do you think are some of California’s Natural Hazards?

Earthquakes Hundreds occur in CA each day…why? –Located on a fault Natural hazards result from earthquakes –Tsunamis- large waves formed from ocean floor shifting –seismic shaking- ground movement during an earthquake –Liquefaction- water-soaked soil turns to liquid, causes collapse of structures –Landslides – loose rock and soil on slopes moves

Volcano Natural Hazards from volcanoes include… –Volcanic ash –Lava flows –Volcanic gases

Storm Hazards Mudflows – wet soil and rock flow quickly downhill, greater hazard after fires Flooding – regional and flash flood –Regional – areas receive too much rain in short period of time –Flash flood – occur in mountains and deserts