1. Session 9: Geological Natural Hazards
These sessions will introduce the basic natural processes, historical geographic ranges, and potential impacts of the natural hazards that are not as unique to the coastal zone.
(Source: USGS)
Session 9: Geological Hazards
Coastal Hazards Management Course
Slide 9. 1, Lecture Outline

2. Introduction: Geological Hazards in the Coastal Zone
Coastal Hazards can be defined as natural hazards that occur within the coastal zone. The hazards discussed in Sessions 8 and 9 can happen in the coastal zone, but occur in other locations as well.
The following geological natural hazards will be discussed in this session:
Earthquakes
Volcanoes
Landslides
Subsidence
Dam Failures
(Source:
(Source:
Session 9: Geological Hazards
Coastal Hazards Management Course
Slide 9. 2, Introduction

3. What is an Earthquake?
(Source: FEMA)
(Source: USGS)
(Source: www. gpsinfo.ru/news/ 2003_1/images/earthquake.jpg )
(Source: NASA)
Tectonic activity can result in motion and cracks on the earth’s surface along many coastlines
(Source: USGS)
Session 9: Geological Hazards
Coastal Hazards Management Course
Slide 9. 3, Earthquakes

4. What is a Volcano? Types of volcanic eruptions include: Icelandic
Hawaiian
Strombolian
Vulcanian
Vesuvian
Pelean
May 17, 1980
Mount St. Helens before, during and after its May 18, 1980 Pelean-type eruption
Volcanoes are often found in coastal areas
1983
May 18, 1980
(Source: USGS & NASA)
Session 9: Geological Hazards
Coastal Hazards Management Course
Slide 9. 4, Volcanoes

5. What is a Landslide?
(Source:
(Source: USGS)
Landslides (also called Debris Flows) occur when masses of rock, earth, or debris move down a slope
Session 9: Geological Hazards
Coastal Hazards Management Course
Slide 9. 5, Landslides

6. What is Subsidence?
The results of subsidence, mine collapse, and sink holes are similar
(Source:
World view of subsidence in large cities
(Source:
Session 9: Geological Hazards
Coastal Hazards Management Course
Slide 9. 6, Subsidence

7. Use the link provided above to watch a simulation of a dam failure.
What is a Dam Failure?
Use the link provided above to watch a simulation of a dam failure.
Dam failures are the result of structural weakening that causes the dam to crack, allow water to enter the structure and eventually break through to release the water stored behind it.
(Source:
Session 9: Geological Hazards
Coastal Hazards Management Course
Slide 9. 7, Dam Failure

8. Earthquake Disasters
(Source: FEMA)
Earthquakes can cause large amounts of fatalities and structural destruction. Over 60 people died in a single California earthquake in 1994.
(Source:
Session 9: Geological Hazards
Coastal Hazards Management Course
Slide 9. 8, Earthquake Disasters

9. Volcano Disasters
(Source: USGS, )
A volcano can destroy forests, property, infrastructure, and spread ash.
Session 9: Geological Hazards
Coastal Hazards Management Course
Slide 9. 9, Volcano Disasters

10. Landslide Disasters
Landslides cause $ 1-2 million in damages each year in the US
(Source: Time)
(Source: USGS)
Session 9: Geological Hazards
Coastal Hazards Management Course
Slide 9. 10, Landslide Disasters

11. Subsidence Disasters
(Source:
(Source:
Coastal zone subsidence will increase as coastal populations increase and groundwater aquifer supply decreases
(Source: USGS )
Session 9: Geological Hazards
Coastal Hazards Management Course
Slide 9. 11, Subsidence Disasters

12. Dam Failure Disasters
Before and after photographs of the St. Francis Dam Break of This event killed 470+ people due to the 180-foot high wall of water that rushed forward into the Santa Clarita Valley of California.
(Source: )
Session 9: Geological Hazards
Coastal Hazards Management Course
Slide 9. 12, Dam Failure Disasters