California’s California’s Natural HazardsNatural Hazards

Chapter 13A, Section 3Chapter 13A, Section 3

California’s Earthquake California’s Earthquake HazardsHazards Natural Hazard –Natural Hazard – an event that results from an event that results from

Earth processes and that can cause damage and Earth processes and that can cause damage and endanger human lifeendanger human life

Natural hazards that result from California’s Natural hazards that result from California’s earthquakes include tsunamis, seismic shaking, earthquakes include tsunamis, seismic shaking, liquefaction, and landslidesliquefaction, and landslides

Scientists have evidence that in the past 200 Scientists have evidence that in the past 200 years, more than a dozen locally generated years, more than a dozen locally generated tsunamis have struck the CA coastlinetsunamis have struck the CA coastline

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

The amount of shaking depends on the rock and The amount of shaking depends on the rock and soil location of an areasoil location of an area

Earthquakes in CA can also cause liquefaction Earthquakes in CA can also cause liquefaction and landslides, collapsing and damaging homesand landslides, collapsing and damaging homes

West Coast Tsunami Warning West Coast Tsunami Warning SystemSystem

Earthquake HazardsEarthquake Hazards

Earthquake HazardsEarthquake Hazards

California’s Volcanic California’s Volcanic HazardsHazards

Natural Hazards from volcanic eruptions in California Natural Hazards from volcanic eruptions in California include volcanic ash, lava flows, and volcanic gasesinclude volcanic ash, lava flows, and volcanic gases

The Cascade Range stretches from Washington into The Cascade Range stretches from Washington into northern CAnorthern CA

Cascade volcanoes in CA include: Black Butte, Mount Cascade volcanoes in CA include: Black Butte, Mount Shasta, Medicine Lake Volcano, and Lassen PeakShasta, Medicine Lake Volcano, and Lassen Peak

The two volcanoes that are classified as active are The two volcanoes that are classified as active are Mount Shasta (late 1700s) and Lassen Peak (early Mount Shasta (late 1700s) and Lassen Peak (early 1900s)1900s)

Volcanic Field –Volcanic Field – an area covered by volcanic rocks an area covered by volcanic rocks The Long Valley Caldera is the focus of a large The Long Valley Caldera is the focus of a large

volcanic field on the eastern side of the Sierra Nevada volcanic field on the eastern side of the Sierra Nevada (some rocks are only a few hundred years old!)(some rocks are only a few hundred years old!)

Carbon dioxide escaping from the ground beneath Carbon dioxide escaping from the ground beneath Mammoth Mountain is killing trees in the areaMammoth Mountain is killing trees in the area

Long Valley Long Valley CalderaCaldera

California’s Storm California’s Storm HazardsHazards

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

The dry conditions in southern CA make it The dry conditions in southern CA make it very susceptible to mudflows and flooding, very susceptible to mudflows and flooding, especially when precipitation is greater than especially when precipitation is greater than normalnormal

A mudflow is a mass of very wet soil, and A mudflow is a mass of very wet soil, and sometimes rock, that flows quickly downhillsometimes rock, that flows quickly downhill

At top speed, a mudflow can move nearly 60 At top speed, a mudflow can move nearly 60 km/hour, destroying everything in its pathkm/hour, destroying everything in its path

Flash floods occur in mountains and deserts; Flash floods occur in mountains and deserts; they can be deadly because the floodwaters they can be deadly because the floodwaters rise rapidly and move quicklyrise rapidly and move quickly

Mudflows and FloodingMudflows and Flooding