california’s resources and natural hazards

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California’s Mineral, Energy, and Soil Resources California’s Water Resources California’s Natural Hazards

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Page 1: California’s Resources and Natural Hazards

California’s Mineral, Energy, and Soil Resources California’s Water Resources California’s Natural Hazards

Page 2: California’s Resources and Natural Hazards

Some of the features of the California landscape formed as the result of tectonic process that took place deep beneath the surface.

Wind, water, ice and other agents of erosion at the surface carved other features of the landscape.

Page 3: California’s Resources and Natural Hazards
Page 4: California’s Resources and Natural Hazards

Three major plates influenced California’s geological history

-North American Plate

-Farallon Plate

-Pacific Plate

The Farallon Plate had convergent boundaries on both east and west sides.

Page 5: California’s Resources and Natural Hazards

As the Farallon plate subducted between the Pacific and North American plates, it disappeared.

Eventually the Pacific and North American Plates came together, the boundary became a transform boundary.

Page 6: California’s Resources and Natural Hazards

The subduction of the Farallon plate had two major results.

- It caused rock to melt. - It caused chunks of rock to collide with

North American Continent.

Page 7: California’s Resources and Natural Hazards

Outline and Identify the tectonic plate movements that lead to geographic features in California

1. Where is the San Andreas Fault located in relation to Los Angeles and San Francisco?

2. What type of fault is the San Andreas? What features are associated with this type of fault?

3. Identify 2 other faults on the Ca map. ◦ What type of fault do you think this fault is?

◦ What features helped you identify this type of fault?

◦ Describe how this fault moves …. boundary zones

Page 8: California’s Resources and Natural Hazards

California is home to the most famous transform boundary in the world.

On land the fault extends about 1000km, from U.S. /Mexican border to Northern California.

The San Andreas is thought to be a system of faults.

Page 9: California’s Resources and Natural Hazards

The San Andreas Fault bends around the Los Angeles area.

Because the fault is not a straight line, It is not 100% transform.

There are parts of it that are convergent. The compression created the San

Bernardino and San Gabriel Mountains

Page 10: California’s Resources and Natural Hazards

San Andreas Fault,

transform boundary, Pacific plate moving north relative to North American plate.

Faulting causes portions of the crust to drop down, forming the Central Valley and Basin and Range Region.

Page 11: California’s Resources and Natural Hazards

Subduction of the Juan de Fuca plate beneath the North American plate produced the Coastal and Cascade Ranges, including Mount Shasta and Lassen Peak (volcanoes).

Page 12: California’s Resources and Natural Hazards

Because of Subduction, a large amount of magma formed in the lithosphere.

The magmas solidified and formed a batholith.

Eventual uplift and erosion created the Sierra Nevada Mountains

Page 13: California’s Resources and Natural Hazards

Today the subduction zone extends from Northern California to Canada.

The result is a chain of volcanoes that extend the entire distance.

It is called the Cascadia Subduction Zone

Page 14: California’s Resources and Natural Hazards

Water erosion has formed V-shaped valleys in various mountain ranges.

Rivers flow slowly on valley floors, leaving thick soil deposits.

Glacial ice movement has carved U-shaped valleys in many mountainous regions.

Page 15: California’s Resources and Natural Hazards

• Soil deposits have produced the Mojave Desert and the Central Valley.

• Wind has eroded soil in the Mojave to create large sand dunes and mineral salt deposits left by evaporation.

• The Central Valley began as an inland sea. Uplifting of the mountains on both sides produced a basin that was later filled with soil washed down from the nearby mountains.

Page 16: California’s Resources and Natural Hazards

California’s major mineral resources include sand, gravel, crushed stone, building stone, gold, silver, iron, evaporate minerals, and clay.

Mineral resources are natural resources that include minerals, rocks and sediment.

These minerals are categorized as industrial, metallic, and nonmetallic minerals.

Page 17: California’s Resources and Natural Hazards

Open text to page CA7 … around pg 390

Read the sections on the three major groups of minerals and bullet the key points in your notes

EX: Industrial Minerals

Sand and gravel most valuable industrial resource-used in road building and construction.

Page 18: California’s Resources and Natural Hazards

Sand and gravel most valuable industrial resource-used in road building and construction.

Crushed stone-limestone that makes cement.

Limestone-used to construct buildings.

Granite-used for making building stone, counter tops, and cemetery markers.

Page 19: California’s Resources and Natural Hazards

• Gold and silver occur in quartz veins in igneous and metamorphic rock.

• Placer deposits-form when dense minerals settle out of moving water.

• Mining areas located in Sierra Nevada, Klamath, and Mojave Desert

• Iron deposits found mostly in the Mojave Desert.

• Iron forms when magma heats rock and water beneath the surface. Iron forms when the rocks cool and deposited in the fractures of rock.

Page 20: California’s Resources and Natural Hazards

Borates form when boron evaporates from water. Fiberglass, detergents, glass, ceramics, and insulation contain borates.

Gypsum-calcium, sulfur, and oxygen compound forms from sulfur-rich waters around hot springs. Used in wallboard, plaster, and cement.

Clay-silicates that contain water. Used in ceramics and bricks.

Page 21: California’s Resources and Natural Hazards

California’s major energy resources ◦ oil,

◦ natural gas

◦ geothermal energy

are the result of geologic processes that occur deep beneath the surface.

Page 22: California’s Resources and Natural Hazards

• Oil – about 15% of the oil produced in the US comes from California.

• As tiny marine organisms die and are buried by sediment, physical and chemical changes convert it to oil.

• Source rocks – rocks, such as shale, in which oil forms

• Reservoir rocks – nearby porous rocks in which oil becomes trapped.

Page 23: California’s Resources and Natural Hazards

Natural gas – California produces nearly 350 billion cubic feet of natural gas.

Gas, composed mainly of methane, often forms along with oil, rising to the top of a reservoir, since it is less dense.

People use natural gas for heating, cooking, and generating electricity.

Page 24: California’s Resources and Natural Hazards

Geothermal energy-leader in the nation in production

Geothermal field – an area where magma that is close to the surface heats ground water.

Engineers drill wells that tap into the steam, with powers turbines to generate electricity.

Page 25: California’s Resources and Natural Hazards

Soil classification based on the area where it forms.

The soils of California include the soils of the Sierras, soils of the Coast Ranges and Cascades, valley soils, and desert soils.

Page 26: California’s Resources and Natural Hazards

Sierra Nevada – tend to be thin and low in humus

Coast Ranges – reddish, acidic low-fertility soil to very fertile, thick dark soils. Amount of rainfall determines that amount of nutrients contained within soil

Valley soils – contain many nutrients, since they are left from river deposits

Desert soils – light sandy soil low in nutrients

Page 27: California’s Resources and Natural Hazards

Conservation is important because of soil erosion. Soil forms very slowly, taking up to 500 years to build up 2.5 cm of soil.

Salinization – build up of salt in the soil from irrigated areas. Evaporation pulls up salty water to the surface. Salt is left as more water evaporates.

Page 28: California’s Resources and Natural Hazards

The main sources of California’s freshwater supply are precipitation, surface water, and groundwater.

More than half the precipitation is lost through evaporation or transpiration. Only 35% stays at the surface or seeps into the ground

Page 29: California’s Resources and Natural Hazards

Precipitation – California averages about 58 cm of precipitation. However, the northern part of the state receives a great deal more rain than the southern part of the state.

Surface water – precipitation flows back into lakes, rivers, and streams that make up drainage basins. Northern part of the state provides more than half the state’s water. The Colorado River also provides water for the state.

Page 30: California’s Resources and Natural Hazards

Groundwater – about 30% of the fresh water used in California.

Aquifers – rocks or soils containing groundwater

Desalination of Sea Water – desalination is the removal of salt from ocean water to obtain fresh water.

Very expensive process

Forced salt water through filters using high pressure

Page 31: California’s Resources and Natural Hazards

To meet freshwater needs throughout the state, California has an intricate network of water storage and distribution systems, or water projects.

Because the population is unevenly distributed, local, state, and federal water projects work together to provide for the state’s water needs.

Page 32: California’s Resources and Natural Hazards

• Local Water Projects – aqueduct, a pipe or channel through which water flows from a higher elevation to a lower elevation.

• Los Angeles Aqueduct carries water from the Owens River to the Los Angeles area.

• Colorado River Aqueduct carries water from the Colorado River to the Los Angeles and San Diego area, but must share water with the fast growing cities in Nevada and Arizona.

Page 33: California’s Resources and Natural Hazards

• State Water Projects – transports rain and melted snow from the Feather River drainage basin to points farther south.

• Provides water for people in the Bay area, the Central Coast, and southern California.

• Supplies water for the crops in the San Joaquin Valley.

• Includes numerous pumps, reservoirs, pipelines, canals, pumping plants, and the California Aqueduct.

Page 34: California’s Resources and Natural Hazards

Federal Water Projects – moves water from Colorado River and Central Valley to irrigate crops. Some water is used in the houses of the Bay area and into wildlife refuges.

Includes the All-American Canal system, the Coachella Canal, and the Central Valley project.

Page 35: California’s Resources and Natural Hazards

• Agriculture – 80% of fresh water used in California goes to irrigating crops.

• Houses and businesses – approximately 380 liters per day per person is used in the US

• Industry – water is used to produce paper and beverages. Also used as a coolant.

• Recreation and Wildlife – areas set aside for recreational activities, such as kayaking, rafting, and fishing, and preserves for fishing and wetland habitats.

Page 36: California’s Resources and Natural Hazards

Natural hazard – an event that results from Earth processes and that can cause damage and endanger human life

Page 37: California’s Resources and Natural Hazards

Earthquake hazards – natural hazards that result from California’s earthquakes include tsunamis, seismic shaking, liquefaction, and landslides.

Hundreds of earthquakes occur each day, but most are so weak that they cannot be felt, usually a magnitude less than 5.

Page 38: California’s Resources and Natural Hazards

Tsunamis – a wave formed when the ocean floor shifts during suddenly during an earthquake

Tsunamis can form when huge undersea landslides of ocean sediment produce large waves.

Even earthquakes far across the Pacific can produce tsunamis in California

Page 39: California’s Resources and Natural Hazards

Seismic shaking – measure of how much ground movement occurs during a quake

Seismic shaking reflects the behavior of earthquakes waves. The waves get smaller further away from the focus.

Seismic shaking also depends on rock and soil conditions of the surrounding area.

Modified Mercalli scale – describes the effects of seismic shaking; how strong an earthquake is felt and how much damage at a particular location

Page 40: California’s Resources and Natural Hazards

Liquefaction – occurs when water-soaked soil turns to a thick, soupy liquid during an earthquake

Landslides – earthquakes often cause loose rock and soil on slopes to move. Usually become more likely after forest fires or periods of droughts.

Page 41: California’s Resources and Natural Hazards

Natural hazards from volcanic eruptions in California include volcanic ash, lava flows, and volcanic gases.

The Cascade Range contains many volcanoes that have erupted over periods of time. Volcanic ash and lava flows are hazards for the surrounding areas. Volcanic field is an area covered by volcanic rocks.

High concentrations of carbon dioxide gas can escape from beneath a volcano, potentially killing plants, animals and people.

Page 42: California’s Resources and Natural Hazards

• Two main storm-related hazards in California are mudflows and flooding.

• Mudflows start in a depression on a steep hillside. The mudflow starts slowly, but picks up speed as it engulfs more loose debris.

• Flooding occurs when too much rain or melted snow fill river channels in a short period of time. Flooding also occurs when excessive rainfall causes dams or levees to fail.