Download Session 9 - Costal Hazards Management Course

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)
Slide 9. 1, Lecture Outline
Session 9: Geological Hazards
Coastal Hazards Management Course
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:http://
www.es.ucsc.e
du/~hyperwww/
subsidence.jpg)
(Source:http://www.geosurv.gov.nf.ca/images/minjpg/volcano.jpg)
Slide 9. 2, Introduction
Session 9: Geological Hazards
Coastal Hazards Management Course
What is an Earthquake?
(Source: FEMA)
(Source: USGS)
(Source: NASA)
(Source: www. gpsinfo.ru/news/
2003_1/images/earthquake.jpg )
Tectonic activity
can result in
motion and cracks
on the earth’s
surface along
many coastlines
(Source: USGS)
Slide 9. 3, Earthquakes
Session 9: Geological Hazards
Coastal Hazards Management Course
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
Slide 9. 4, Volcanoes
1983
May 18, 1980
(Source: USGS & NASA)
Session 9: Geological Hazards
Coastal Hazards Management Course
What is a Landslide?
(Source:
http://www.she
ehanpipeline.c
om/images/lan
dslide.jpg)
(Source: USGS)
Landslides (also called Debris Flows) occur when masses of rock,
earth, or debris move down a slope
Slide 9. 5, Landslides
Session 9: Geological Hazards
Coastal Hazards Management Course
What is Subsidence?
The results of
subsidence,
mine collapse,
and sink holes
are similar
(Source: http://www.dnr.state.oh.us/geosurvey/geo_fact/geo_f12.htm)
World view of
subsidence in
large cities
(Source: www.mhhe.com)
Slide 9. 6, Subsidence
Session 9: Geological Hazards
Coastal Hazards Management Course
What is a Dam Failure?
http://simscience.org/cracks/movies/superman.mov
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: http://simscience.org)
Slide 9. 7, Dam Failure
Session 9: Geological Hazards
Coastal Hazards Management Course
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:
http://www.sfmuseum.org/hist/pix49.html)
Slide 9. 8, Earthquake Disasters
Session 9: Geological Hazards
Coastal Hazards Management Course
Volcano Disasters
(Source: USGS,
http://vulcan.wr.usgs.gov/Photo/Volcanoes/framework.html )
A volcano can destroy forests, property, infrastructure, and spread ash.
Slide 9. 9, Volcano Disasters
Session 9: Geological Hazards
Coastal Hazards Management Course
Landslide Disasters
Landslides cause $ 1-2
million in damages each
year in the US
(Source: Time)
(Source: USGS)
Slide 9. 10, Landslide Disasters
Session 9: Geological Hazards
Coastal Hazards Management Course
Subsidence Disasters
(Source:
http://www.sewerhis
tory.org/images/mi/
mid/mid_spdwy01.jp
g)
(Source:
http://www.phill
yblast.com/Alle
ntown/sinkhole.
htm)
(Source: USGS )
Slide 9. 11, Subsidence Disasters
Coastal zone
subsidence will
increase as coastal
populations increase
and groundwater
aquifer supply
decreases
Session 9: Geological Hazards
Coastal Hazards Management Course
Dam Failure Disasters
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.
(Source: http://www.scvhistory.com/scvhistory/stfrancis.htm )
Slide 9. 12, Dam Failure Disasters
Session 9: Geological Hazards
Coastal Hazards Management Course