# Presentation: 532095

## Session 9: Geological

- 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.

**Session 9: Geological**
**Natural Hazards**

- (Source:  USGS)

**Session 9: Geological Hazards**
**Coastal Hazards Management Course**

**Slide 9. 1, Lecture Outline**

## Introduction: Geological Hazards in the Coastal Zone

**Slide 9. ****, Introduction**

- 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:http://www.es.ucsc.edu/~hyperwww/subsidence.jpg)

**Session 9: Geological Hazards**
**Coastal Hazards Management Course**

- (Source:http://www.geosurv.gov.nf.ca/images/minjpg/volcano.jpg)

## What is an Earthquake? 

- What is an Earthquake?

**Slide 9. ****, Earthquakes**

- (Source: FEMA)

- Tectonic activity can result in motion and cracks on the earth’s surface along many coastlines

**Session 9: Geological Hazards**
**Coastal Hazards Management Course**

- (Source: USGS)

- (Source: NASA)

- (Source: www. gpsinfo.ru/news/ 2003_1/images/earthquake.jpg** **)

- (Source: USGS)

## What is a Volcano? 

- What is a Volcano?

**Slide 9. ****, Volcanoes**

- (Source: USGS & NASA)

-  Mount St. Helens before, during and after its May 18, 1980 Pelean-type eruption
** **Volcanoes are   often found in coastal areas

**Session 9: Geological Hazards**
**Coastal Hazards Management Course**

- May 18, 1980

- May 17, 1980

- 1983

- Types of volcanic eruptions include:

-  Icelandic
-  Hawaiian
-  Strombolian
-  Vulcanian
-  Vesuvian
-  Pelean

## What is a Landslide? 

- What is a Landslide?

**Slide 9. ****, Landslides**

- (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**

- (Source: http://www.sheehanpipeline.com/images/landslide.jpg)

## What is Subsidence? 

- What is Subsidence?

**Slide 9. ****, Subsidence**

**Session 9: Geological Hazards**
**Coastal Hazards Management Course**

- (Source: http://www.dnr.state.oh.us/geosurvey/geo_fact/geo_f12.htm)

- (Source: www.mhhe.com)

- World view of subsidence in large cities

- The results of subsidence, mine collapse, and sink holes are similar

## What is a Dam Failure? 

- What is a Dam Failure?

**Slide 9. ****, Dam Failure**

- (Source: http://simscience.org)

- 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.

- _[http://simscience.org/cracks/movies/superman.mov](http://simscience.org/cracks/movies/superman.mov)__ _

**Session 9: Geological Hazards**
**Coastal Hazards Management Course**

## Earthquake Disasters

**Slide 9. ****, Earthquake Disasters**

- (Source: FEMA)

- (Source: http://www.sfmuseum.org/hist/pix49.html)

- Earthquakes can cause large amounts of fatalities and structural destruction. Over 60 people died in a single California earthquake in 1994.

**Session 9: Geological Hazards**
**Coastal Hazards Management Course**

## Volcano Disasters 

- Volcano Disasters

**Slide 9. ****, Volcano Disasters**

- (Source: USGS, http://vulcan.wr.usgs.gov/Photo/Volcanoes/framework.html** **)

**Session 9: Geological Hazards**
**Coastal Hazards Management Course**

- A volcano can destroy forests, property, infrastructure, and spread ash.

## Landslide Disasters

**Slide 9. ****, Landslide Disasters**

- (Source: USGS)

- Landslides cause $ 1-2 million in damages each year in the US

**Session 9: Geological Hazards**
**Coastal Hazards Management Course**

- (Source: Time)

## Subsidence Disasters 

- Subsidence Disasters

**Slide 9. ****, Subsidence Disasters**

- (Source: http://www.sewerhistory.org/images/mi/mid/mid_spdwy01.jpg)

**Session 9: Geological Hazards**
**Coastal Hazards Management Course**

- (Source: http://www.phillyblast.com/Allentown/sinkhole.htm)

- (Source: USGS** **)

- Coastal zone subsidence will increase as coastal populations increase and groundwater aquifer supply decreases

## Dam Failure Disasters 

- Dam Failure Disasters

**Slide 9. ****, Dam Failure Disasters**

- (Source: http://www.scvhistory.com/scvhistory/stfrancis.htm** **)

- Before and after photographs of the St. Francis Dam Break of 1928.  This event killed 470+ people due to the 180-foot high wall of water that rushed forward into the Santa Clarita Valley of California.

**Session 9: Geological Hazards**
**Coastal Hazards Management Course**