> **Session No. 9**

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**Course Title: Coastal Hazards Management**

**Session Title: Geological Hazards**

**Author: Katherine Eschelbach, University of North Carolina at Chapel
Hill**

**Time: 50 minutes**

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**Objectives**

> 9.1 Understand the basic natural processes that contribute to the
> following geological hazards: earthquake, landslide, volcanoes,
> sinkholes, and dam failure

9.2 Discuss the historical impacts and destructive potential of these
hazards

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**Scope:**

Sessions 8 and 9 introduce students to the major natural hazards that
can occur both inside and outside of the coastal zone. Assuming many of
the students do not have an extensive background in the earth and
physical sciences, the material is very basic. These sessions discuss
the natural processes that contribute to these major natural hazards,
where these hazards occur, the frequency of their occurrence, and the
impacts they may have on both the human and the natural environments.
The purpose of these two sessions is to give a broad overview of some
hazards that are not unique but which may affect the coastal zone.

Session 8 (*Meteorological Hazards*) covers the natural processes that
contribute to five selected meteorologically driven hazards. These five
hazards include: tornado, drought, severe thunderstorm, blizzard and
wildfire.

Session 9 (*Geological Hazards*) introduces the natural processes
involved in five geologically driven hazards (earthquake, dam failure,
landslide, volcano, and sink holes). Session 9 also addresses the
impacts that these hazards may have on both humans and the environment.

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**Supplemental Considerations:**

The internet is a tremendous resource for background information on the
hazards discussed in both Sessions 8 and 9. Many of the federal
government websites cited in the lecture remarks below, such as the USGS
and FEMA websites, are reliable and provide large amounts of information
for students and the public. The students should become familiar with
several of the websites as powerful resources of information.

An optional homework assignment, in addition to the student and
additional readings below, could be to assign the students these three
websites to become familiar with these hazards and summarize their
findings for the class (as they pertain to the hazards in Sessions 8 and
9):

[www.noaa.gov](http://www.noaa.gov/)

[www.usgs.gov](http://www.usgs.gov/)

[www.fema.gov](http://www.fema.gov/)

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**Readings:**

*Instructor and Student Reading:*

Abbott, P.L. 1996. *Natural Disasters.* Dubuque, IA:Wm. C. Brown
Publishers. Pp. 45-57, 61-

73, 124-126: "Earthquakes", pp.153-188: "Volcanoes", pp. 191-227:
"Landslides and

> Subsidence", pp. 314-315: "Dams".

*Additional Background Reading:*

Alexander, Grant. 1993. *Natural Disasters.* New York, NY: Chapman &
Hall, Inc. Pp. 41-111

"Earthquakes and Volcanoes", pp. 242-286: "Landslides and Subsidence",
pp. 356-368:

"Dam disasters".

Bolt, B.A., W.L. Horn, G.A. Macdonald, R.F. Scott. 1977. *Geological
Hazards, 2^nd^ ed.* New

York, NY: Springer-Verlag. Pp. 1-62: "Hazards from Earthquakes", pp.
63-131:

"Hazards from Volcanoes", pp. 148-197: "Hazards from Landslides", pp.
198-220:

"Hazards from Ground Subsidence". Springer-Verlag. New York, NY.

Evans, S.G. and J.V. DeGraff. 2002. *Catastrophic landslides : effects,
occurrence, and*

*mechanisms.* Boulder, Colorado: Geological Society of America.

Francis, Peter. 2004. *Volcanoes, 2^nd^ ed*. Oxford: Oxford University
Press.

Hallowell, Christopher.  Holding Back The Sea: The Struggle for
America\'s Natural Legacy on

the Gulf Coast. New York:  HarperCollins Publishers.  2001.

McGuire, Bill. 2002. *Raging planet : earthquakes, volcanoes, and the
tectonic threat to life on*

*Earth.* Hauppauge, NY: Barron\'s Publishing.

Robinson, Andrew. 2002. *Earthshock: Hurricanes, Volcanoes, Earthquakes,
Tornadoes and*

*Other Forces of Nature, 2nd ed.* London: Thames and Hudson Ltd. pp.
47-80:

"Earthquakes", pp. 81-116: "Volcanoes".

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**PowerPoint slides:**

**Part II: Session 9**

\[**PowerPoint 9.1** Lecture Outline\]

\[**PowerPoint 9.2** Introduction: Geological Hazards in the Coastal
Zone\]

\[**PowerPoint 9.3** What is an Earthquake?\]

\[**PowerPoint 9.4** What is a Volcano?\]

\[**PowerPoint 9.5** What is a Landslide?\]

\[**PowerPoint 9.6** What is Subsidence?\]

\[**PowerPoint 9**.**7** What is a Dam Failure?\]

\[**PowerPoint 9**.**8** Earthquake Disaster\]

\[**PowerPoint 9.9** Volcano Disaster\]

\[**PowerPoint 9.10** Landslide Disaster\]

\[**PowerPoint 9.11** Subsidence Disaster\]

\[**PowerPoint 9.12** Dam Failure Disaster\]

**Handouts:**

\[**Handout 9.1** Earthquake Scale\]

### 

###  \[Handout 9.2 Dam Failure \]

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**General Requirements:**

The Instructor should review some of the additional background reading
and prepare copies of handouts for students based on the accompanying
PowerPoint presentation.

As foundation classes, Sessions 6 through 9 will present baseline
information in a predominantly lecture format, supported by PowerPoint
slides. The slides are an essential part of this lecture series, as they
depict the natural hazards that will be discussed throughout the course.

Because sessions 8 and 9 cover natural hazards that are not solely
coastal in nature, the instructor may choose to assign the material in
these sessions as background reading, and give an abbreviated lecture
instead. The PowerPoint slides can then be used to prompt interactive
discussion of problems, issues and solutions -- drawing from theory and
seeking to develop and hone student analytical and critical thinking
skills.

The following slide will be used for the lecture outline for Session 9:

> \[**PowerPoint 9.1** Lecture Outline\]

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**Objective 9.1:** Understand the basic natural processes that
contribute to the following

> geological hazards: earthquake, volcano, landslide, subsidence, and
> dam failure

**Requirements:**

The content should be presented as lecture, supported by PowerPoint
slides. **Handouts 9.1 -9.2** are provided within the Remarks for this
objective as well as an appendix at the end of this document for
distribution.

The following slides will be used during this objective:

\[**PowerPoint 9.2** Introduction: Geological Hazards in the Coastal
Zone\]

\[**PowerPoint 9.3** What is an Earthquake?\]

\[**PowerPoint 9.4** What is a Volcano?\]

\[**PowerPoint 9.5** What is a Landslide?\]

\[**PowerPoint 9.6** What is Subsidence?\]

\[**PowerPoint 9**.**7** What is a Dam Failure?\]

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**Remarks:**

**II. Introduction: Other Natural Hazards in the Coastal Zone**

\[**PowerPoint 9.2** Introduction: Geological Hazards in the Coastal
Zone\]

1.  A natural hazard is a natural process that occurs under certain
    extreme environmental

> conditions in the atmosphere, on the earth's surface, or under the
> ground.

-   Natural hazards are often a source of astonishment and fear as well
    as respect

> for humans because of the awesome power that they contain.

2.  There are many different types of natural hazards, such as
    tornadoes, blizzards, drought,

> wildfire, volcanoes and earthquakes. ***Coastal hazards are those
> natural hazards that occur at the interface between the ocean and the
> shoreline.*** The hazards that are most uniquely tied to the coastal
> zone were presented in Sessions 6 and 7.

3.  The hazards that will be discussed in this session include several
    geological hazards

> that are not as unique to the coastal zone. These hazards include:
> earthquakes, volcanoes, landslides, subsidence, and dam failure.

**III. What is an Earthquake?**

> \[**PowerPoint 9.3** What is an Earthquake?\]

A. Definition

1.  ***Earthquakes are geologic events that involve movement or shaking
    of the earth\'s crust.***

2.  Earthquakes are usually caused by the release of stresses
    accumulated as a result of the rupture of rocks along opposing fault
    planes in the earth\'s outer crust.

-   These fault planes are typically found along borders of the earth\'s
    ten tectonic plates. These plate borders generally follow the
    outlines of the continents, with the North American plate following
    the continental border with the Pacific Ocean in the west, but
    following the mid-Atlantic trench in the east.

-   As earthquakes occurring in the mid-ocean trench usually pose little
    threat to humans, unlike earthquakes located along continental
    boundaries, the greatest earthquake threat in North America is along
    the Pacific coast.

3.  The areas of greatest tectonic instability occur at the perimeters
    of the slowly moving plates, as these locations are subjected to the
    greatest strains from plates traveling in opposite directions and at
    different speeds.

4.  Deformation along plate boundaries causes strain in the rock and the
    consequent buildup of stored energy. When the built-up stress
    exceeds the rocks\' strength, a rupture occurs.

-   The rock on both sides of the fracture is snapped, releasing the
    stored energy and producing seismic waves, generating an earthquake.

**B. Description**

1.  Earthquakes are measured in terms of their magnitude and intensity.

-   Magnitude is measured using the Richter Scale, an open-ended
    logarithmic scale that describes the energy release of an earthquake
    through a measure of shock wave amplitude.

    -   Each unit increase in magnitude on the Richter Scale corresponds
        to a ten-fold increase in wave amplitude, or a 32-fold increase
        in energy (USGS, 1996).

-   Intensity is most commonly measured using the Modified Mercalli
    Intensity (MMI) Scale (Bryant, 1991).

    -   It is a twelve-level scale based on direct and indirect
        measurements of seismic effects.

    -   The scale levels are typically described using roman numerals,
        with:

        i.  I corresponding to imperceptible (instrumental) events,

        ii. IV corresponding to moderate (felt by people awake), to

        iii. XII for catastrophic (total destruction).

    -   A detailed description of the Modified Mercalli Scale of
        Earthquake Intensity (and its correspondence to the Richter
        Scale) is shown below:

**Handout 9.1: Modified Mercalli Scale of Earthquake Intensity**

  ----------- --------------- ------------------------------ -------------- -----------------
  **Scale**   **Intensity**   **Description of Effects**     **Maximum      **Corresponding
                                                             Acceleration   Richter Scale**
                                                             (mm/sec)**     

  I           Instrumental    Detected only on seismographs  \<10           

  II          Feeble          Some people feel it            \<25           \<4.2

  III         Slight          Felt by people resting; like a \<50           
                              truck rumbling by                             

  IV          Moderate        Felt by people walking         \<100          

  V           Slightly Strong Sleepers awake; church bells   \<250          \<4.8
                              ring                                          

  VI          Strong          Trees sway; suspended objects  \<500          \<5.4
                              swing, objects fall off                       
                              shelves                                       

  VII         Very Strong     Mild Alarm; walls crack;       \<1000         \<6.1
                              plaster falls                                 

  VIII        Destructive     Moving cars uncontrollable;    \<2500         
                              masonry fractures, poorly                     
                              constructed buildings damaged                 

  IX          Ruinous         Some houses collapse; ground   \<5000         \<6.9
                              cracks; pipes break open                      

  X           Disastrous      Ground cracks profusely; many  \<7500         \<7.3
                              buildings destroyed;                          
                              liquefaction and landslides                   
                              widespread                                    

  XI          Very Disastrous Most buildings and bridges     \<9800         \<8.1
                              collapse; roads, railways,                    
                              pipes and cables destroyed;                   
                              general triggering of other                   
                              hazards                                       

  XII         Catastrophic    Total destruction; trees fall; \>9800         \>8.1
                              ground rises and falls in                     
                              waves                                         
  ----------- --------------- ------------------------------ -------------- -----------------

**IV. What is a Volcano?**

> \[**PowerPoint 9.4** What is a Volcano?\]

A. Definition

1.  *A volcano is a vent in the surface of the Earth through which magma
    and associated gases and ash erupt; also, the form or structure,
    usually conical, that is produced by the ejected material.*[^1]

### B. Description

1.  A volcanic eruption occurs when superheated rock under the earth's
    surface rises to areas of lower pressure at the surface. During this
    movement, a phase change occurs from solid rock to liquid magma and
    results in volume expansion, further conversion from rock to magma,
    and finally eruption.

2.  Some volcanoes erupt violently, while others flow more peacefully.
    This is due to:

-   Variance in chemical and mineral content of the rock/magma

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-   Variance in the viscosity, temperature, and water and gas content of
    the rock/magma

-   Variance in geographic positions in relation to tectonic plate edges

3.  Types of volcanic eruption include:

-   *Icelandic* -- gas escapes easily and lava has low viscosity

-   *Hawaiian* -- gas also escapes easily, but lava has slightly more
    viscosity. Builds tall peaks.

-   *Strombolian* -- has smaller, but more continuous eruptions. Its
    central lava pool is easily triggered due to the pressure that
    builds quickly under its crust.

-   *Vulcanian* -- switch between high viscosity lava and large amounts
    of ash blown out the top of the volcano.

-   *Vesuvian* -- even more violent high viscosity lava blasts that are
    due to trapped gases. These gases can blow ash and rock great
    distances, either vertically or horizontally.

-   *Pelean* -- the gas pressure and viscosity of the magma is so high
    that these volcanoes blow lava and ash out of its side (rather than
    up) to relieve the pressure blockages of the throat of the volcano.
    (Example = Mt. St. Helen's)

> **Types of Volcanic Eruptions**
>
> ![](media/image1.png){width="6.481944444444444in"
> height="3.0027777777777778in"}
>
> (Source: Abbott, P. 1996: p. 160, *Natural Disasters.* Dubuque, IA:
> Wm.C. Brown Publishers.)

4.  Hot spots are areas of rock in the earth's mantle that slowly rise
    toward the surface and create volcanic eruptions.

-   An example of a hotspot is in Hawaii: typically these volcanic
    eruptions are preceded by earthquakes and the built up gases are
    able to escape through the crack in the surface, creating a "curtain
    of fire".

-   The greatest number of hotspots can be found beneath the Atlantic
    Ocean's African Plate

**V. What is a Landslide?**

> \[**PowerPoint 9.5** What is a Landslide?\]

**A. Definition**

1.  ***Landslides occur when masses of rock, earth, or debris move down
    a slope.***

2.  Landslides may be very small or very large, and can move at slow to
    very high speeds.

3.  They are activated by storms and fires and by human modification of
    the land.

**B. Description**

1.  Landslides pose serious threats to highways and structures that
    support fisheries, tourism, timber harvesting, mining, and energy
    production as well as general transportation.

2.  Deadly manifestations of landslides are debris flows. Gori and
    Burton[^2] explain that while some landslides move slowly and cause
    damage gradually, others move so rapidly that they can destroy
    property and take lives suddenly and unexpectedly.

-   The latter constitute debris flows (also referred to as mudslides,
    mudflows, or debris avalanches), which are a common type of
    fast-moving landslide that generally occurs during intense rainfall
    on water-saturated soil.

-   They usually start on steep hillsides as soil slumps or slides that
    liquefy and accelerate to speeds as great as 35 miles per hour or
    more.

-   They continue flowing down hills and into channels and deposit sand,
    mud, boulders, and organic material onto more gently sloping ground.

-   Their consistency ranges from watery mud to thick, rocky mud (like
    wet cement), which is dense enough to carry boulders, trees, and
    cars.

-   Debris flows from many different sources can combine in channels,
    where their destructive power may be greatly increased.

3.  Landslides are especially troubling because they often occur with
    other natural hazards, such as earthquakes and floods.

4.  Areas that are generally prone to landslide hazards include existing
    old landslides; the bases of steep slopes; the bases of drainage
    channels; and developed hillsides where leach-field septic systems
    are used.

5.  Areas that are typically considered safe from landslides include
    areas that have not moved in the past; relatively flat-lying areas
    away from sudden changes in slope; and areas at the top or along
    ridges, set back from the tops of slopes.

![](media/image2.png){width="4.625694444444444in"
height="3.4611111111111112in"}

*Landslide Areas in the Contiguous United States. Areas in color are
areas of high to moderate incidence of landslides, plus areas of
moderate incidence but high susceptibility to land sliding. Incidence of
land slides is high when greater than 15% of the area is actually part
of a landslide or other ground failure. Moderate incidence means that
1.5 to 15% of the area is involved in mappable landslides.*

**VI. What is Subsidence?**

> \[**PowerPoint 9.6** What is Subsidence?\]

*Subsidence, Sink Holes, and Mine Collapse are all documented below for
possible discussion.*

SUBSIDENCE

# **A. Definition**

1.  Land subsidence occurs when large amounts of ground water have been
    withdrawn from certain types of rocks, such as fine-grained
    sediments.

2.  The rock compacts because the water is partly responsible for
    holding the ground up. When the water is withdrawn, the rock falls
    in on itself.[^3]

**B. Description**

1.  Some instances of land subsidence can be attributed to heavy pumping
    of ground water from aquifers.

-   The figure below displays an example of the rate of subsidence at
    Cove City, NC and the increase in the second interval covered in the
    leveling runs (from 1968 to 1978) from 0.17 to 0.25 inches per year.
    This can be explained by New Bern bringing their Cove City water
    supply wells on-line in the late 1960s. ***Higher rates of land
    subsidence are associated with higher ground water withdrawal
    rates.***[^4]

![](media/image3.png){width="5.000694444444444in"
height="3.3027777777777776in"}

*Land subsidence rates for selected North Carolina coastal cities*.[^5]

2.  About 25 square miles of coastal Louisiana is disappearing due, in
    large\
    measure (sea-level rise not unimportant), to subsidence
    annually.[^6]

    -   According to the Environmental Literacy Council,
        ([http://www.enviroliteracy.org/ article.php/
        1129.html](http://www.enviroliteracy.org/ article.php/ 1129.html))
        "the major factors contributing to the loss of Louisiana\'s
        coastal lands are natural forces and processes exacerbated by
        human activities".

        1.  The natural sediment transport down the Mississippi usually
            is enough to replenish and counteract the naturally
            occurring slight subsidence of the soils at the mouth of the
            river. These soils sink simply due to their own weight over
            time. However, if no additional soils are added, the soils
            will continue to sink below sea level. Humans have attempted
            to protect themselves from flooding due to the sinking soils
            by building levees, which hold back the rising water levels,
            but continue to restrict the soils even further because the
            levees prevent the soil from reaching and replenishing the
            delta deposits. This, in turn, only adds to the loss of land
            and puts these populations at greater risk to flooding as
            the subsidence is exacerbated.

        2.  The Environmental Literacy Council also lists several other
            websites as references detailing the issues surrounding
            subsidence in Louisiana's coastal areas. Students are
            encouraged to visit the ELC's website (Cited above) for more
            information and links. Several of the sites listed as links
            are listed below:

            a.  NOAA Magazine: "Subsidence and Sea Level Rise in
                Louisiana":
                <http://www.magazine.noaa.gov/stories/mag101.htm>

            b.  USGS Louisiana Coastal Land Loss:
                <http://www.nwrc.usgs.gov/special/landloss.htm>

            c.  National Geographic "Louisiana Losing Ground at a
                Catastrophic Rate":
                <http://magma.nationalgeographic.com/ngm/0410/feature5/>

            d.  Tallahassee Democrat "Worries Rise as Wetlands Sink":
                <http://www.tallahassee.com/mld/democrat/news/local/6822482.htm>

**Sink Holes**

# A. Definition

1.  ***A sinkhole is a naturally occurring, roughly circular depression
    in the land surface***, formed most commonly in areas of limestone
    bedrock.

-   Limestone is a type of rock composed entirely of the highly reactive
    mineral calcite (CaCO3), which readily dissolves in the presence of
    slightly acidic ground water.

-   In areas of humid climate, rain water percolates downward through
    the soil cover into openings in the limestone bedrock, gradually
    dissolving the rock matrix.

-   Void spaces in the subsurface will eventually form, ranging from
    microscopic to cavern size.[^7]

**B. Description**

1.  In most areas of the southeastern United States, the limestone
    bedrock is not directly exposed at the surface, but is covered by a
    variable thickness of sand, silt and clay. This overburden may
    bridge subsurface cavities for long periods of time.

    -   Eventually a catastrophic collapse of the overburden into the
        subsurface cavity may occur, and a sinkhole is formed. This type
        of sinkhole is known as a **cover collapse sinkhole**.

2.  A cover collapse sinkhole is just one end of the sinkhole spectrum.
    At the opposite end of the spectrum is the **cover subsidence
    sinkhole**, formed where overburden is relatively thin (a few feet
    to tens of feet).

-   In this setting, as subsurface solution occurs, the land surface
    gradually subsides into the void space below, since it lacks the
    cohesiveness to form a significant \"bridge\" across the void.

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-   Cover-subsidence sinkholes are often mistaken for other land
    subsidence features, since they do not form in as spectacular a
    manner as the cover-collapse sinkhole.

-   One common indicator of this type of sinkhole is the formation of
    cracks in nearby buildings or in roads.[^8]

3.  Under natural conditions, sinkholes usually form rather slowly, over
    the course of many years. However, some human activities can trigger
    abrupt sinkhole formation, or accelerate processes that have been
    going on for a long time.

-   Activities such as dredging, diversion of surface drainage systems,
    or pumping of ground water can accelerate the natural growth of
    sinkholes.[^9]

**MINE COLLAPSE**

# A. Definition

1.  In the context of underground mining, mine collapse can be
    considered a type of subsidence or sink hole.

-   ***It is the lowering of the Earth\'s surface due to collapse of
    bedrock and unconsolidated materials (sand, gravel, silt, and clay)
    into underground mined areas***.[^10]

 

**B. Description**

2.  There are two types of mine collapse:

-   \(1\) **pit**, also called sinkhole or pothole, and

-   \(2\) **sag** or trough. (The term \"sinkhole\" more properly refers
    to solution collapse features in limestone.)

-   **Pit subsidence** is characterized by an abrupt sinking of the
    surface, resulting in a circular steep-sided, craterlike feature
    that has an inward drainage pattern.

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-   It is associated with roof collapse of mines that have total
    overburden (overlying unconsolidated material and rock) of less than
    165 feet, weak roof rock of shale or mudstone, and a ratio of
    unconsolidated-material thickness to rock thickness of less than
    1.2. Pit subsidence does not occur where the thickness of the
    unconsolidated overburden is more than 90 feet.

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-   **Sag subsidence** is a gentle, gradual settling of the surface. It
    is associated with pillar crushing or pillar punching (discussed
    below) of deeper mines (overburden of more than 75 feet).

    -   Sag-subsidence features may fill with water if the surface of
        the subsidence intersects the water table. Pit-subsidence
        features generally do not hold water because the pit drains into
        the underlying mine.[^11]

![](media/image4.png){width="3.3118055555555554in"
height="2.0305555555555554in"}

*Diagrammatic cross section of typical subsidence resulting from
mine-roof collapse.*

**VII. What is a Dam Failure?**

> \[**PowerPoint 9.7** What is a Dam Failure?\]

*Note to the Instructor: A link to a short Quick-Time video of a dam
break is included in this slide. \*It is important to test out this link
before the class is in session to ensure that the software necessary to
run the video is available on the computer. The video can be accessed by
copying the complete link/web address into a new internet browser. It is
recommended that the instructor prepare the link before class and bring
up the internet browser at the appropriate discussion time during the
lecture to play the video. If the video will not work, the students can
write down the internet address for viewing during their own time.*

**A. Definition**

1.  *Dams store water in reservoirs during times of excess flow, so that
    water can be released from the reservoir during the times that
    natural flows are inadequate to meet the needs of water users.*[^12]
    *Dams can pose risks to communities if not designed, operated, and
    maintained properly.*

2.  Many dam failures have resulted because of an inability to safely
    pass flood flows. Failures caused by hydrologic conditions can range
    from sudden, with complete breaching or collapse, to gradual, with
    progressive erosion and partial breaching.

-   The most common modes of failure associated with hydrologic
    conditions include overtopping, erosion of earth spillways, and
    overstressing the dam or its structural components.[^13]

**B. Description**

1.  Like all built structures, dams deteriorate. Lack of maintenance
    causes dams to be more susceptible to failure.

2.  Dam incidents are events such as large floods, earthquakes or
    inspections that alert dam safety engineers to deficiencies that
    threaten the safety of a dam.

-   Due to limited staff, many incidents are not reported, and therefore
    the actual number of incidents is likely to be much greater.

-   The hazard potential is the possible adverse incremental
    consequences that result from the release of water or stored
    contents due to failure of the dam or disoperation of the dam or
    appurtenances.

3.  Dam failures can be grouped into three categories; low, significant
    and high hazard potential situations.

-   Hazard potential does not indicate the structural integrity of the
    dam itself, but rather the effects if a failure should occur.

-   The hazard potential assigned to a dam is based on consideration of
    the effects of a failure during both normal and flood flow
    conditions.[^14]

-   The table below (*Handout 9.2)* gives a description and guidelines
    of the three classes of dam hazards.

Handout 9.2 Dam Hazard Classifications

+-----------------------+-----------------------+-----------------------+
| **Dam Hazard          |                       |                       |
| Classification**[^15] |                       |                       |
+-----------------------+-----------------------+-----------------------+
| ***Hazard             | ***Description***     | ***Quantitative       |
| Classification***     |                       | Guidelines***         |
+-----------------------+-----------------------+-----------------------+
| **Low**               | Interruption of road  | Less than 25 vehicles |
|                       | service, low volume   | per day; Less than    |
|                       | roads; Economic       | \$30,000              |
|                       | Damage                |                       |
+-----------------------+-----------------------+-----------------------+
| **Intermediate        | Damage to highways,   | 25 to less than 250   |
| (Significant)**       | Interruption of       | vehicles per day;     |
|                       | service; Economic     | \$30,000 to less than |
|                       | Damage                | \$200,000             |
+-----------------------+-----------------------+-----------------------+
| **High**              | Loss of human life;   | Probable loss of 1 or |
|                       | Economic Damage       | more human lives;     |
|                       |                       | More than \$200,000   |
|                       | \*Probable loss of    | \* 250 Vehicles per   |
|                       | human life due to     | day at 1000 ft        |
|                       | breached roadway or   | visibility;100        |
|                       | bridge on or below    | Vehicles per day at   |
|                       | the dam               | 500 ft visibility; 25 |
|                       |                       | Vehicles per day at   |
|                       |                       | 200 ft visibility     |
+-----------------------+-----------------------+-----------------------+

\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_

**Objective 9.2 Discuss the historical impacts and destructive potential
of these hazards**

**Requirements:**

The content should be presented as lecture, supported by PowerPoint
slides. **Handouts 9.3-9.5** are provided within the Remarks for this
objective as well as an appendix at the end of this document.

The following slides will be used during this objective:

\[**PowerPoint 9**.**8** Earthquake Disasters\]

\[**PowerPoint 9.9** Volcano Disasters\]

\[**PowerPoint 9.10** Landslide Disasters\]

\[**PowerPoint 9.11** Subsidence Disasters\]

\[**PowerPoint 9.12** Dam Failure Disasters\]

\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_

**Remarks:**

**VIII. Earthquake Disasters**

\[**PowerPoint 9.8** Earthquake Disasters\]

**Handout 9.3: Earthquake Information**

Taken from: <http://earthquake.usgs.gov/bytopic/lists.html>

**The Largest Earthquakes in the United States**

  --------- ------------------------------------------------------------------------------ ------------------------ ---------------
  ** **     **Location**                                                                   **Date Time UTC**        **Magnitude**

  **1.**    [Prince William Sound,                                                         1964 03 28 03:36:14.0    9.2
            Alaska](http://neic.usgs.gov/neis/eq_depot/usa/1964_03_28.html)                UTC                      

  **2.**    [Andreanof Islands,                                                            1957 03 09 14:22:31.9    9.1
            Alaska](http://neic.usgs.gov/neis/eq_depot/usa/1957_03_09.html)                UTC                      

  **3.**    [Rat Islands, Alaska](http://neic.usgs.gov/neis/eq_depot/usa/1965_02_04.html)  1965 02 04 05:01 UTC     8.7

  **4.**    [East of Shumagin Islands,                                                     1938 11 10 20:18:41.2    8.2
            Alaska](http://neic.usgs.gov/neis/eq_depot/usa/1938_11_10.html)                UTC                      

  **5.**    [New Madrid,                                                                   1811 12 16 08:15 UTC     8.1
            Missouri](http://neic.usgs.gov/neis/eq_depot/usa/1811-1812.html#december_16)                            

  **6.**    [Yakutat Bay, Alaska](http://neic.usgs.gov/neis/eq_depot/usa/1899_09_10.html)  1899 09 10 21:41 UTC     8.0

  **7.**    [Andreanof Islands,                                                            1986 05 07 22:47 UTC     8.0
            Alaska](http://neic.usgs.gov/neis/eq_depot/usa/1986_05_07.html)                                         

  **8.**    [New Madrid,                                                                   1812 02 07 09:45 UTC     8.0
            Missouri](http://neic.usgs.gov/neis/eq_depot/usa/1811-1812.html#february_7)                             

  **9.**    [Near Cape Yakataga,                                                           1899 09 04 00:22 UTC     7.9
            Alaska](http://neic.usgs.gov/neis/eq_depot/usa/1899_09_04.html)                                         

  **10.**   [Fort Tejon,                                                                   1857 01 09 16:24 UTC     7.9
            California](http://neic.usgs.gov/neis/eq_depot/usa/1857_01_09.html)                                     

  **11.**   [Ka\'u District, Island of                                                     1868 04 03 02:25 UTC     7.9
            Hawaii](http://neic.usgs.gov/neis/eq_depot/usa/1868_04_03.html)                                         

  **12.**   [Gulf of Alaska,                                                               1987 11 30 19:23 UTC     7.9
            Alaska](http://neic.usgs.gov/neis/eq_depot/usa/1987_11_30.html)                                         

  **13.**   Andreanof Islands, Alaska                                                      1996 06 10 04:03 UTC     7.9

  **14.**   [Denali Fault, Alaska](http://neic.usgs.gov/neis/eq_depot/2002/eq_021103/)     2002 11 03 22:12 UTC     7.9

  **15.**   [New Madrid,                                                                   1812 01 23 15:00 UTC     7.8
            Missouri](http://neic.usgs.gov/neis/eq_depot/usa/1811-1812.html#january_23)                             

  **16.**   [Imperial Valley,                                                              1892 02 24 07:20 UTC     7.8
            California](http://neic.usgs.gov/neis/eq_depot/usa/1892_02_24.html)                                     

  **17.**   [San Francisco,                                                                1906 04 18 13:12 UTC     7.8
            California](http://neic.usgs.gov/neis/eq_depot/usa/1906_04_18.html)                                     

  **18.**   Gulf of Alaska                                                                 1988 03 06 22:35 UTC     7.8
  --------- ------------------------------------------------------------------------------ ------------------------ ---------------

**Deaths from Earthquakes in the United States**

  ------------------ --------------------------- ------------------------
  **Date - UTC**     **Earthquake Locality**     **Deaths**

  December 16, 1811  Northeast Arkansas -\       Several
  -\                 New Madrid, Missouri        
  February 7, 1812                               

  December 8, 1812   San Juan Capistrano,        40
                     California                  

  December 21, 1812  Santa Barbara, California   1

  January 9, 1857    Fort Tejon, California      1

  April 3, 1868      Hawaii Island, Hawaii       77\
                                                 (landslides: 31,
                                                 tsunami: 46)

  October 21,1868    Hayward, California         30

  March 26, 1872     Owens Valley, California    27

  May 10, 1877       Hawaii Island, Hawaii       5

  September 1, 1886  Charleston, South Carolina  60

  April 19, 1892     Vacaville, California       1

  December 25, 1899  San Jacinto, California     6

  April 18, 1906     San Francisco, California   about 3,000\
                                                 (earthquake and fire)

  June 23, 1915      Imperial Valley, California 6

  April 21, 1918     San Jacinto, California     1

  June 29, 1925      Santa Barbara, California   13

  June 29, 1926      Santa Barbara, California   1

  June 6, 1932       Eureka, California          1

  March 11, 1933     Long Beach, California      115

  October 19, 1935   Helena, Montana             2

  October 31, 1935   Helena, Montana             2

  May 19, 1940       Imperial Valley, California 9

  April 1, 1946      Aleutian Islands, Alaska    165\
                                                 (tsunami: 159 Hawaii,\
                                                 5 Alaska, 1 California)

  April 13, 1949     Puget Sound, Washington     8

  July 21, 1952      Kern County, California     12

  August 22, 1952    Kern County, California     2

  December 21, 1954  Eureka, California          1

  October 24, 1955   Concord, California         1

  March 22, 1957     Daly City, California       1

  July 10, 1958      Southeastern Alaska         5

  August 18, 1959    Hebgen Lake, Montana        28

  May 21, 1960       Chile, South America\       61
                     (tsunami in Hawaii)         

  March 28, 1964     Prince William Sound,       125\
                     Alaska                      (tsunami: 98 Alaska,\
                                                 11 California, 1 Oregon\
                                                 earthquake: 15 Alaska)

  April 29, 1965     Seattle, Washington         7

  October 2, 1969    Santa Rosa, California      1

  February 9, 1971   San Fernando, California    65

  November 29, 1975  Hawaii Island, Hawaii       2

  October 28, 1983   Borah Peak, Idaho           2

  October 1, 1987    Los Angeles-Whittier,       8
                     Cailfornia                  

  October 4, 1987    Los Angeles-Whittier,       1
                     California                  

  August 8, 1989     Santa Cruz County,          1
                     California                  

  October 18, 1989   Santa Cruz County,          63
                     California                  

  June 28, 1991      Southern California         2

  June 28, 1992      Landers, California         3

  September 21, 1993 Oregon                      2

  January 17, 1994   Northridge, California      60

  February 3, 1995   Wyoming                     1

  December 22, 2003  Central California          2
  ------------------ --------------------------- ------------------------

*Abridged from Seismicity of the United States, 1568-1989 (Revised), by
Carl W. Stover and Jerry L. Coffman, U.S. Geological Survey Professional
Paper 1527, United States Government Printing Office, Washington: 1993,
and* [*Significant Earthquakes of the
World*](http://neic.usgs.gov/neis/eqlists/significant.html).

**IX. Volcano Disasters**

\[**PowerPoint 9**.**9** Volcano Disasters\]

**Handout 9.4: Volcano Information**

**\
**Taken from:
<http://volcano.und.nodak.edu/vwdocs/frequent_questions/top_101/Interesting/Interesting6.html>

**A Big Ten list of eruptions based on explosive force and destruction
in historical time would include:** (VEI = Volcanic Eruption Index,
scale of 1- 7)

1.  Tambora, Indonesia 1815: VEI=7, 92,000 casualties

2.  Santorini, Greece 1628 B.C.: VEI=6, unknown casualties

3.  Krakatau, Indonesia 1883: VEI=6, 36,400 casualties

4.  Santa Maria, Guatemala 1902: VEI=6, 6,000 casualties

5.  Mount St. Helens, USA 1980: VEI=5, 57 casualties

6.  Vesuvius, Italy 79: VEI=5, 3,360 casualties

7.  Pinatubo, Philippines 1991: VEI=5, 932 casualties

8.  Mount Pelee, Martinique 1902: VEI=4, 29,000 casualties

9.  Nevado del Ruiz, Columbia 1985: VEI=3, 23,000 casualties

10. Unzen, Japan 1792: VEI=2, 15,000 casualties.

### What are some of the more famous volcanic eruptions?

**about 1500 B.C.** - the destruction of
[Thera](http://volcano.und.edu/vwdocs/volc_images/europe_west_asia/santorini.html )
in the eastern Mediterranean and the end of the Minoan civilization
(which is the basis for the legend of Atlantis)\
**A.D. 79** - eruption of
[Vesuvius](http://volcano.und.edu/vwdocs/volc_images/img_vesuvius.html)
buried the Roman cities of Pompeii and Herculeneum\
**1783** - eruption of
[Laki](http://volcano.und.edu/vwdocs/volc_images/europe_west_asia/laki.html),
Iceland, caused a severe famine, which resulted in the deaths of 20
percent of the population of Iceland\
**1815** -
[Tambora](http://volcano.und.edu/vwdocs/volc_images/southeast_asia/indonesia/tambora.html),
Indonesia, the largest historical eruption\
**1883** -
[Krakatau](http://volcano.und.nodak.edu/vwdocs/current_volcs/krakatau/krakatau.html),
Indonesia, resulted in a huge tsunami, which drowned 36,000 people\
**1912** - Katmai, Alaska, largest eruption of the 20th century

\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_

Taken from: <http://volcanoes.usgs.gov/Products/FAQs/FAQ_EQ+Volc.html>

***"Is there a relationship between large earthquakes (\>M 6) that occur
along major fault zones and nearby volcanic eruptions?***

Sometimes, yes. A few historic large regional earthquakes (\>M 6) are
considered by scientists to be related to a subsequent eruption or to
some type of unrest at a nearby volcano. The exact triggering mechanism
for these historic examples is not well understood, but the volcanic
activity probably occurs in response to a change in the local pressure
surrounding the magma reservoir system as a consequence of (1) severe
ground shaking caused by the earthquake; or (2) a change in the
\"strain\" or pressure in the Earth\'s crust in the region surrounding
where the earthquake occurred."

*Note to Instructor: One or two of the descriptions below can be
discussed with the class as examples based on the interest of the class.
It is not intended that all examples be discussed during the allotted
time period.*

### Historic Examples

#### Kilauea Volcano, Hawaii

**1975:** A large earthquake (7.2 on the Richter Scale) struck the Big
Island of Hawaii at 4:48 a.m. on November 29, 1975. It was centered
about 28 kilometers southeast of Kilauea Volcano\'s summit caldera at a
depth of 5 kilometers; the earthquake occurred within the volcano\'s
south flank. The earthquake was preceded by numerous foreshocks, the
largest of which was a 5.7 magnitude jolt at 3:36 the same morning, and
was accompanied, or closely followed, by a tsunamis (seismic sea wave),
massive ground movements, hundreds of aftershocks, and a short-lived
eruption in Kilauea\'s summit caldera.

The eruption began at 5:32 a.m. from a 500-meter long fissure on the
caldera floor and ended by 10:00 p.m. According to scientists at the
USGS Hawaiian Volcano Observatory, the eruptive activity \"was
apparently triggered by the 7.2 magnitude earthquake. The small volume
and brief duration of the eruption suggest that the shallow magma might
not have reached the surface under its own buoyant energy without a
triggering mechanism apparently provided by the violent ground
shaking.\"

Source:

*Tilling, Robert I., Koyanagi, Robert Y., Lipman, Peter W., Lockwood,
John P., Moore, James G., and Swanson, Donald A., 1976, Earthquake and
related catastrophic events, Island of Hawaii, November 29, 1975: A
preliminary report: U.S. Geological Survey Circular 740, 33 p.*

**1868:** The largest historic earthquake (estimated between 7.5 and
8.1) on the Big Island occurred beneath the south flank of Mauna Loa
Volcano on April 2, 1868. The earthquake was followed by a small
eruption from Kilauea\'s southwest rift zone and from a fissure on the
caldera wall that flooded the adjacent Kilauea Iki crater with lava.
Also, within Kilauea\'s caldera, part of the floor subsided about 90
meters. This activity occurred nearly simultaneously with an eruption
from the southwest rift zone of Mauna Loa volcano.

Source:

*Macdonald, Gordon A., Abbott, Agatin T., and Peterson, Frank L., 1983
(2nd edition), Volcanoes in the Sea \-- The geology of Hawaii: Honolulu,
University of Hawaii Press, 517 p.*

#### Mount Pinatubo, Philippines

Mount Pinatubo\'s huge explosive eruption on June 15, 1991, occurred
within 11 months of a magnitude 7.8 earthquake that occurred about 100
kilometers northeast of the volcano. Many scientists have since asked,
\"Was the eruption triggered by, or otherwise related to the earthquake
that had occurred on July 16, 1990?\" A recent study by scientists of
the Philippine Institute of Volcanology and Seismology and the U.S.
Geological Survey Study suggest that there was indeed a relationship
between the two events.

The study suggests that the \"failure stress along faults of the
Pinatubo area\" after the big earthquake \"were probably not a cause of
Pinatubo\'s awakening. However, compressive stress on the magma
reservoir and its roots was about 1 bar, possibly enough to squeeze a
small volume of basalt into the overlying dacitic reservoir.
Alternately, strong ground shaking associated with the Luzon earthquake
might have done the same or triggered movement along previously stressed
faults that in turn allowed magma ascent.\"

Source:

*Bautista, B.C., Bautista, L.P., Stein, R.S., Barcelona, E.S.,
Punongbayan, R.S., Laguerta, E.P., Rasdas, A.R., Ambubuyog, G., and
Amin, E.Q., [Relationship of Regional and Local Structures to Mount
Pinatubo Activity](http://pubs.usgs.gov/pinatubo/bbautist/index.html)
in: Newhall, C.G., Punongbayan, R.S. (eds.) Fire and mud: Eruptions and
lahars of Mt. Pinatubo, Philippines, Philippine Institute of Volcanology
and Seismology, Quezon City and University of Washington Press, Seattle
p. 351- 370.*

#### Restless Calderas

A recent study of the historic activity at calderas from around the
world showed that \"caldera unrest occurred at least 79 times in close
temporal association with regional earthquakes or, in a few instances,
with swarms of regional earthquakes. By close temporal association we
mean within a time span that is short in relation to the usual
recurrence intervals of both the regional earthquakes and the unrest,
usually within a few months or less.\"

\"Fifty regional earthquakes (most M 6 and above) were followed within
hours to months of unrest at nearby calderas\... Twenty seven of these
episodes culminated in eruptions, and three others are continuing
without eruptions as yet (Rabaul, Wrangell, and Yellowstone).\" Rabaul
caldera in Papua New Guinea erupted in 1994.

The authors also found that \"at least 27 regional earthquakes occurred
within 100 kilometers of a restless caldera during or shortly after
caldera unrest\" and concluded \"that magma bodies beneath young
calderas often react to changes in regional tectonic strain, and that
unrest at calderas is sometimes a general, long-range precursor to
regional earthquakes.\"

Source:

*Newhall, Christopher, G., and Dzurisin, Daniel, 1988, Historic Unrest
at Large Calderas of the World: U.S. Geological Survey Bulletin 1855,
vol 1, p. 19-20.*

**X. Landslide Disasters**

\[**PowerPoint 9.10** Landslide Disasters\]

1.  ***According to the United States Geological Survey (USGS),
    landslides are a major geologic hazard that occur in all 50 states,
    cause \$1-2 billion in damages and result in an average of more than
    25 fatalities each year.***

*Note to Instructor: One or two of the descriptions below can be
discussed with the class as examples based on the interest of the class.
It is not intended that all ten be discussed during the allotted time
period.*

**Selected recent individual and regional landslide events in the US**

Taken from: Highland, L.M. and R.L. Schuster. 2003. Significant
Landslide Events in the United States. United States Geological Survey
provisional report. Found at:
<http://landslides.usgs.gov/html_files/pubs/report1/Landslides_pass_508.pdf>

![](media/image5.png){width="6.49375in" height="8.172916666666667in"}

![](media/image6.png){width="4.438194444444444in"
height="6.374305555555556in"}

**Handout 9.5: 1997-98 El Nino driven Landslides in the US**

![](media/image7.png){width="5.803472222222222in"
height="5.251388888888889in"}

**XI. Subsidence Disasters**

\[**PowerPoint 9.11** Subsidence Disasters\]

***Description of picture of the building in a sinkhole (Slide 9.11):***

Taken from: <http://www.phillyblast.com/Allentown/sinkhole.htm>

## 

## Allentown Corporate Plaza

"The 7-story modern office building known as Corporate Plaza was built
in downtown Allentown in 1986. Many local residents regarded it as a
landmark achievement in Allentown\'s downtown revitalization efforts.
But that all changed during the early morning hours of February 23,
1994.\
The winter of 1993-1994 had been one of the region\'s worst in memorable
history. It\'s an area that sees a few isolated winter storms each year.
But that particular year saw ice storm after ice storm, followed by
several heavy snowstorms. The runoff from all these storms finally took
its toll in the form of a sinkhole in front of Corporate Plaza. The
widening hole was discovered around 4:00 am by utility crews
investigating a water main break. Fortunately, no one was in the office
building at that early hour.\
\
By 6:30 am the situation had worsened. The gaping hole had spread
underneath one of the main support columns of the building. The column
gave way, causing a V-shaped sag in the front facade. Because of the
danger the building posed, a raze-or-repair order was issued to the
building\'s owner.

On February 27, the sinkhole was pumped full of concrete in an attempt
to stabilize the building enough for salvage crews to save what they
could inside, as well permit the demolition crews to begin preparing it
for implosion.\
\
Implosion was determined to be the quickest and safest method of
bringing Corporate Plaza to the ground. With the building stabilized as
well as it could be given the circumstances,
[Dykon](http://www.dykon-blasting.com/), a reputable blasting firm from
the Midwest, was brought in to do the job. But working inside a
progressively failing building, made it anything but a routine
demolition.\
\
Dave Hersey, Dykon\'s project manager, told Phillyblast that it was the
scariest job he had ever worked on. \"That building was in the process
of sinking into the street while we were working. The stresses and loads
inside the building were changing constantly. Some of the upper columns
were twisting and some of them were failing under the pressure. We had
to be so careful. We had people doing nothing but watching the cuts we
made in the steel columns for movement.\"

A close-up shot of the northeast corner shows the extent of the damage
along 7th street. The tilting column that the worker is standing by was
the second column to give way along the front facade. In the background,
now stripped of its brick cladding, is the first column that fell. Its
failure caused the other front columns to deflect under the increasing
load they were required to bear.

The demolition process was slowed by continuing bad weather and the
constant shifting of the building. Continual efforts were made to
stabilize it to prevent total collapse. Despite their best attempts, the
northwest corner of the building eventually gave way, collapsing down to
the fourth floor.

The building was successfully imploded on March 19, 1994, 3 1/2 weeks
after the catastrophe had begun."

\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_

***Description of the picture of the street sinkhole (Slide 9.11):***

Taken from: <http://www.sewerhistory.org/grfx/misc/spdwy1.htm>

"On September 7, 2002, two sinkholes appeared on Speedway Blvd., a major
street in Tucson, Arizona. The initial cause of the sinkholes remains
unclear, but the 42\" sewer main which was crushed and plugged was aging
and scheduled for renovation in the near future. The sewer line was a
large interceptor that carried 32 million gallons of sewage (peak dry
weather flow) a day from the south side of Tucson to the 42 mgd Roger
Road Treatment Plant. This is the western sinkhole, the second and
smaller of the sinkholes that appeared within hours of the first signs
of pavement disturbance. Photo date September 7, 2002.

Source: Jaime Rivera, Pima County Wastewater Management Department"

\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_

Taken from: <http://wwwga.usgs.gov/edu/earthgwlandsubside.html>

+-----------------------------------------------------------------------+
| ### Ground-water pumping and land subsidence                          |
|                                                                       |
| Compaction of soils in some aquifer systems can accompany excessive   |
| ground-water pumping and it is by far the single largest cause of     |
| subsidence. Excessive pumping of such aquifer systems has resulted in |
| permanent subsidence and related ground failures. In some systems,    |
| when large amounts of water are pumped, the subsoil compacts, thus    |
| reducing in size and number the open pore spaces in the soil the      |
| previously held water. This can result in a permanent reduction in    |
| the total storage capacity of the aquifer system.                     |
|                                                                       |
| ![](media/image8.png){width="5.333333333333333in"                     |
| height="3.9166666666666665in"}                                        |
+-----------------------------------------------------------------------+

♦ USGS Fact Sheet 165-00 [Land Subsidence in the United
States](http://water.usgs.gov/ogw/pubs/fs00165/).

Information on this page is from *Waller, Roger M., Ground Water and the
Rural Homeowner, Pamphlet, U.S. Geological Survey, 1982*

**XII. Dam Failure Disasters**

\[**PowerPoint 9.12** Dam Failure Disasters\]

1.  In the event of a dam failure, the energy of the water stored behind
    even a small dam is capable of causing loss of life and great
    property damage if there are people downstream of the dam.[^16]

```{=html}
<!-- -->
```
2.  In the past two years more than 520 dam incidents, including 61 dam
    failures, were reported to the National Performance of Dams Program,
    which collects and archives information on dam performance as
    reported by state and federal regulatory agencies and dam owners.

***Description of dam failure pictures in Slide 9.12:***

Taken from: <http://www.scvhistory.com/scvhistory/ap2333a.htm>

"Photo, looking north, shows what was left of the St. Francis Dam
shortly after it failed on March 12, 1928.

Construction on the 600-foot-long, 185-foot-high St. Francis Dam started
in August 1924. With a 12.5 billion-gallon capacity, the reservoir began
to fill with water on March 1, 1926. It was completed two months later.

At 11:57:30 p.m. on March 12, 1928, the dam failed, sending a
180-foot-high wall of water crashing down San Francisquito Canyon. An
estimated 470 people lay dead by the time the floodwaters reached the
Pacific Ocean south of Ventura 5 1/2 hours later.

It was the second-worst disaster in California history, after the great
San Francisco earthquake and fire of 1906, in terms of lives lost."

**Appendix A: Handouts**

**Handout 9.1: Modified Mercalli Scale of Earthquake Intensity**

  ----------- --------------- ------------------------------ -------------- ----------------- ------------
  **Scale**   **Intensity**   **Description of Effects**     **Maximum      **Corresponding   
                                                             Acceleration   Richter Scale**   
                                                             (mm/sec)**                       

  I           Instrumental    Detected only on seismographs  \<10                             

  II          Feeble          Some people feel it            \<25                             \<4.2

  III         Slight          Felt by people resting; like a \<50                             
                              truck rumbling by                                               

  IV          Moderate        Felt by people walking         \<100                            

  V           Slightly Strong Sleepers awake; church bells   \<250                            \<4.8
                              ring                                                            

  VI          Strong          Trees sway; suspended objects  \<500                            \<5.4
                              swing, objects fall off                                         
                              shelves                                                         

  VII         Very Strong     Mild Alarm; walls crack;       \<1000                           \<6.1
                              plaster falls                                                   

  VIII        Destructive     Moving cars uncontrollable;    \<2500                           
                              masonry fractures, poorly                                       
                              constructed buildings damaged                                   

  IX          Ruinous         Some houses collapse; ground   \<5000                           \<6.9
                              cracks; pipes break open                                        

  X           Disastrous      Ground cracks profusely; many  \<7500                           \<7.3
                              buildings destroyed;                                            
                              liquefaction and landslides                                     
                              widespread                                                      

  XI          Very Disastrous Most buildings and bridges     \<9800                           \<8.1
                              collapse; roads, railways,                                      
                              pipes and cables destroyed;                                     
                              general triggering of other                                     
                              hazards                                                         

  XII         Catastrophic    Total destruction; trees fall; \>9800                           \>8.1
                              ground rises and falls in                                       
                              waves                                                           
  ----------- --------------- ------------------------------ -------------- ----------------- ------------

Handout 9.2 Dam Hazard Classifications

+-----------------------+-----------------------+-----------------------+
| **Dam Hazard          |                       |                       |
| Classification**      |                       |                       |
+-----------------------+-----------------------+-----------------------+
| ***Hazard             | ***Description***     | ***Quantitative       |
| Classification***     |                       | Guidelines***         |
+-----------------------+-----------------------+-----------------------+
| **Low**               | Interruption of road  | Less than 25 vehicles |
|                       | service, low volume   | per day; Less than    |
|                       | roads; Economic       | \$30,000              |
|                       | Damage                |                       |
+-----------------------+-----------------------+-----------------------+
| **Intermediate        | Damage to highways,   | 25 to less than 250   |
| (Significant)**       | Interruption of       | vehicles per day;     |
|                       | service; Economic     | \$30,000 to less than |
|                       | Damage                | \$200,000             |
+-----------------------+-----------------------+-----------------------+
| **High**              | Loss of human life;   | Probable loss of 1 or |
|                       | Economic Damage       | more human lives;     |
|                       |                       | More than \$200,000   |
|                       | \*Probable loss of    | \* 250 Vehicles per   |
|                       | human life due to     | day at 1000 ft        |
|                       | breached roadway or   | visibility;100        |
|                       | bridge on or below    | Vehicles per day at   |
|                       | the dam               | 500 ft visibility; 25 |
|                       |                       | Vehicles per day at   |
|                       |                       | 200 ft visibility     |
+-----------------------+-----------------------+-----------------------+

**Handout 9.3: Earthquake Information**

Taken from: <http://earthquake.usgs.gov/bytopic/lists.html>

**The Largest Earthquakes in the United States**

  --------- ------------------------------------------------------------------------------ ------------------------ ---------------
  ** **     **Location**                                                                   **Date Time UTC**        **Magnitude**

  **1.**    [Prince William Sound,                                                         1964 03 28 03:36:14.0    9.2
            Alaska](http://neic.usgs.gov/neis/eq_depot/usa/1964_03_28.html)                UTC                      

  **2.**    [Andreanof Islands,                                                            1957 03 09 14:22:31.9    9.1
            Alaska](http://neic.usgs.gov/neis/eq_depot/usa/1957_03_09.html)                UTC                      

  **3.**    [Rat Islands, Alaska](http://neic.usgs.gov/neis/eq_depot/usa/1965_02_04.html)  1965 02 04 05:01 UTC     8.7

  **4.**    [East of Shumagin Islands,                                                     1938 11 10 20:18:41.2    8.2
            Alaska](http://neic.usgs.gov/neis/eq_depot/usa/1938_11_10.html)                UTC                      

  **5.**    [New Madrid,                                                                   1811 12 16 08:15 UTC     8.1
            Missouri](http://neic.usgs.gov/neis/eq_depot/usa/1811-1812.html#december_16)                            

  **6.**    [Yakutat Bay, Alaska](http://neic.usgs.gov/neis/eq_depot/usa/1899_09_10.html)  1899 09 10 21:41 UTC     8.0

  **7.**    [Andreanof Islands,                                                            1986 05 07 22:47 UTC     8.0
            Alaska](http://neic.usgs.gov/neis/eq_depot/usa/1986_05_07.html)                                         

  **8.**    [New Madrid,                                                                   1812 02 07 09:45 UTC     8.0
            Missouri](http://neic.usgs.gov/neis/eq_depot/usa/1811-1812.html#february_7)                             

  **9.**    [Near Cape Yakataga,                                                           1899 09 04 00:22 UTC     7.9
            Alaska](http://neic.usgs.gov/neis/eq_depot/usa/1899_09_04.html)                                         

  **10.**   [Fort Tejon,                                                                   1857 01 09 16:24 UTC     7.9
            California](http://neic.usgs.gov/neis/eq_depot/usa/1857_01_09.html)                                     

  **11.**   [Ka\'u District, Island of                                                     1868 04 03 02:25 UTC     7.9
            Hawaii](http://neic.usgs.gov/neis/eq_depot/usa/1868_04_03.html)                                         

  **12.**   [Gulf of Alaska,                                                               1987 11 30 19:23 UTC     7.9
            Alaska](http://neic.usgs.gov/neis/eq_depot/usa/1987_11_30.html)                                         

  **13.**   Andreanof Islands, Alaska                                                      1996 06 10 04:03 UTC     7.9

  **14.**   [Denali Fault, Alaska](http://neic.usgs.gov/neis/eq_depot/2002/eq_021103/)     2002 11 03 22:12 UTC     7.9

  **15.**   [New Madrid,                                                                   1812 01 23 15:00 UTC     7.8
            Missouri](http://neic.usgs.gov/neis/eq_depot/usa/1811-1812.html#january_23)                             

  **16.**   [Imperial Valley,                                                              1892 02 24 07:20 UTC     7.8
            California](http://neic.usgs.gov/neis/eq_depot/usa/1892_02_24.html)                                     

  **17.**   [San Francisco,                                                                1906 04 18 13:12 UTC     7.8
            California](http://neic.usgs.gov/neis/eq_depot/usa/1906_04_18.html)                                     

  **18.**   Gulf of Alaska                                                                 1988 03 06 22:35 UTC     7.8
  --------- ------------------------------------------------------------------------------ ------------------------ ---------------

**Deaths from Earthquakes in the United States**

  ------------------ --------------------------- ------------------------
  **Date - UTC**     **Earthquake Locality**     **Deaths**

  December 16, 1811  Northeast Arkansas -\       Several
  -\                 New Madrid, Missouri        
  February 7, 1812                               

  December 8, 1812   San Juan Capistrano,        40
                     California                  

  December 21, 1812  Santa Barbara, California   1

  January 9, 1857    Fort Tejon, California      1

  April 3, 1868      Hawaii Island, Hawaii       77\
                                                 (landslides: 31,
                                                 tsunami: 46)

  October 21,1868    Hayward, California         30

  March 26, 1872     Owens Valley, California    27

  May 10, 1877       Hawaii Island, Hawaii       5

  September 1, 1886  Charleston, South Carolina  60

  April 19, 1892     Vacaville, California       1

  December 25, 1899  San Jacinto, California     6

  April 18, 1906     San Francisco, California   about 3,000\
                                                 (earthquake and fire)

  June 23, 1915      Imperial Valley, California 6

  April 21, 1918     San Jacinto, California     1

  June 29, 1925      Santa Barbara, California   13

  June 29, 1926      Santa Barbara, California   1

  June 6, 1932       Eureka, California          1

  March 11, 1933     Long Beach, California      115

  October 19, 1935   Helena, Montana             2

  October 31, 1935   Helena, Montana             2

  May 19, 1940       Imperial Valley, California 9

  April 1, 1946      Aleutian Islands, Alaska    165\
                                                 (tsunami: 159 Hawaii,\
                                                 5 Alaska, 1 California)

  April 13, 1949     Puget Sound, Washington     8

  July 21, 1952      Kern County, California     12

  August 22, 1952    Kern County, California     2

  December 21, 1954  Eureka, California          1

  October 24, 1955   Concord, California         1

  March 22, 1957     Daly City, California       1

  July 10, 1958      Southeastern Alaska         5

  August 18, 1959    Hebgen Lake, Montana        28

  May 21, 1960       Chile, South America\       61
                     (tsunami in Hawaii)         

  March 28, 1964     Prince William Sound,       125\
                     Alaska                      (tsunami: 98 Alaska,\
                                                 11 California, 1 Oregon\
                                                 earthquake: 15 Alaska)

  April 29, 1965     Seattle, Washington         7

  October 2, 1969    Santa Rosa, California      1

  February 9, 1971   San Fernando, California    65

  November 29, 1975  Hawaii Island, Hawaii       2

  October 28, 1983   Borah Peak, Idaho           2

  October 1, 1987    Los Angeles-Whittier,       8
                     California                  

  October 4, 1987    Los Angeles-Whittier,       1
                     California                  

  August 8, 1989     Santa Cruz County,          1
                     California                  

  October 18, 1989   Santa Cruz County,          63
                     California                  

  June 28, 1991      Southern California         2

  June 28, 1992      Landers, California         3

  September 21, 1993 Oregon                      2

  January 17, 1994   Northridge, California      60

  February 3, 1995   Wyoming                     1

  December 22, 2003  Central California          2
  ------------------ --------------------------- ------------------------

*Abridged from Seismicity of the United States, 1568-1989 (Revised), by
Carl W. Stover and Jerry L. Coffman, U.S. Geological Survey Professional
Paper 1527, United States Government Printing Office, Washington: 1993,
and* [*Significant Earthquakes of the
World*](http://neic.usgs.gov/neis/eqlists/significant.html).

**Handout 9.4: Volcano Information**

**\
**Taken from:
<http://volcano.und.nodak.edu/vwdocs/frequent_questions/top_101/Interesting/Interesting6.html>

**A Big Ten list of eruptions based on explosive force and destruction
in historical time would include:** (VEI = Volcanic Eruption Index,
scale of 1- 7)

11. Tambora, Indonesia 1815: VEI=7, 92,000 casualties

12. Santorini, Greece 1628 B.C.: VEI=6, unknown casualties

13. Krakatau, Indonesia 1883: VEI=6, 36,400 casualties

14. Santa Maria, Guatemala 1902: VEI=6, 6,000 casualties

15. Mount St. Helens, USA 1980: VEI=5, 57 casualties

16. Vesuvius, Italy 79: VEI=5, 3,360 casualties

17. Pinatubo, Philippines 1991: VEI=5, 932 casualties

18. Mount Pelee, Martinique 1902: VEI=4, 29,000 casualties

19. Nevado del Ruiz, Columbia 1985: VEI=3, 23,000 casualties

20. Unzen, Japan 1792: VEI=2, 15,000 casualties.

### What are some of the more famous volcanic eruptions?

**about 1500 B.C.** - the destruction of
[Thera](http://volcano.und.edu/vwdocs/volc_images/europe_west_asia/santorini.html )
in the eastern Mediterranean and the end of the Minoan civilization
(which is the basis for the legend of Atlantics)\
**A.D. 79** - eruption of
[Vesuvius](http://volcano.und.edu/vwdocs/volc_images/img_vesuvius.html)
buried the Roman cities of Pompeii and Herculeneum\
**1783** - eruption of
[Laki](http://volcano.und.edu/vwdocs/volc_images/europe_west_asia/laki.html),
Iceland, caused a severe famine, which resulted in the deaths of 20
percent of the population of Iceland\
**1815** -
[Tambora](http://volcano.und.edu/vwdocs/volc_images/southeast_asia/indonesia/tambora.html),
Indonesia, the largest historical eruption\
**1883** -
[Krakatau](http://volcano.und.nodak.edu/vwdocs/current_volcs/krakatau/krakatau.html),
Indonesia, resulted in a huge tsunami, which drowned 36,000 people\
**1912** - Katmai, Alaska, largest eruption of the 20th century

**Handout 9.5: 1997-98 El Nino driven landslide events in the US**

Taken from: Highland, L.M. and R.L. Schuster. 2003. Significant
Landslide Events in the United States. United States Geological Survey
provisional report. Found at:
<http://landslides.usgs.gov/html_files/pubs/report1/Landslides_pass_508.pdf>

![](media/image7.png){width="5.803472222222222in"
height="5.251388888888889in"}

**Appendix B: Course Developer References**

Bates, R.L., and Jackson, J.A., 1987, Glossary of geology: American
Geological Institute, Alexandria, Virginia, 788 p; and
<http://volcano.und.nodak.edu/vwdocs/frequent_questions/top_101/Volcanoes/Volcanoes9.html>

<http://geohazards.cr.usgs.gov/html_files/nlic/bludridge.htm>

[http://wwwga.usgs.gov/edu/earthgwlandsubside.html]{.underline}

<http://www.ncwater.org/Permits_and_Registration/Capacity_Use/Central_>

[Coastal_Plain/landsub.php]{.underline}

<http://www.ncwater.org/Permits_and_Registration/Capacity_Use/Central_>

[Coastal_Plain/landsub.php]{.underline}

[http://www.ncwater.org/About_DWR/Division_of_Water_Resources/Water_Allocation_Section](http://www.ncwater.org/About_DWR/Division_of_Water_Resources/Water_Allocation_Section%0D              Ground_Water_Branch/Sinkhole/)

[Ground_Water_Branch/Sinkhole/](http://www.ncwater.org/About_DWR/Division_of_Water_Resources/Water_Allocation_Section%0D              Ground_Water_Branch/Sinkhole/)

[http://www.ncwater.org/About_DWR/Division_of_Water_Resources/Water_Allocation_Section](http://www.ncwater.org/About_DWR/Division_of_Water_Resources/Water_Allocation_Section%0D              Ground_Water_Branch/Sinkhole/)

[Ground_Water_Branch/Sinkhole/](http://www.ncwater.org/About_DWR/Division_of_Water_Resources/Water_Allocation_Section%0D              Ground_Water_Branch/Sinkhole/)

[http://www.ncwater.org/About_DWR/Division_of_Water_Resources/Water_Allocation_Section](http://www.ncwater.org/About_DWR/Division_of_Water_Resources/Water_Allocation_Section%0D               Ground_Water_Branch/Sinkhole/)

[Ground_Water_Branch/Sinkhole/](http://www.ncwater.org/About_DWR/Division_of_Water_Resources/Water_Allocation_Section%0D               Ground_Water_Branch/Sinkhole/)

[http://www.dnr.state.oh.us/geosurvey/geo_fact/geo_f12.htm]{.underline}

[http://www.dnr.state.oh.us/geosurvey/geo_fact/geo_f12.htm]{.underline}

<http://www.ussdams.org/howdam.html>

<http://www.fema.gov/fima/damsafe/idf_iiib.shtm>

<http://www.fema.gov/fima/damsafe/idf_iiib.shtm>

<http://dlr.enr.state.nc.us/damhazardclas.html>

<http://www.fema.org/hazards/damsafety/>

<http://earthquake.usgs.gov/bytopic/lists.html>

<http://volcano.und.nodak.edu/vwdocs/frequent_questions/top_101/Interesting/Interesting6.html>

<http://volcanoes.usgs.gov/Products/FAQs/FAQ_EQ+Volc.html>

Highland, L.M. and R.L. Schuster. 2003. Significant Landslide Events in
the United States.

United States Geological Survey provisional report.

Found at:
<http://landslides.usgs.gov/html_files/pubs/report1/Landslides_pass_508.pdf>

<http://www.phillyblast.com/Allentown/sinkhole.htm>

<http://www.sewerhistory.org/grfx/misc/spdwy1.htm>

<http://wwwga.usgs.gov/edu/earthgwlandsubside.html>

<http://www.scvhistory.com/scvhistory/ap2333a.htm>

<http://www.enviroliteracy.org/article.php/1129.html>

**Appendix C: Power Point Graphics Citations**

**Part II: Session 9**

**PowerPoint 9.1:** Lecture Outline

-   (Source: USGS)

**PowerPoint 9.2** Introduction: Geological Hazards in the Coastal Zone

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

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

**PowerPoint 9.3** What is an Earthquake?

-   (Source: NASA)

-   (Source: USGS)

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

**PowerPoint 9.4** What is a Volcano?

-   (Source: USGS & NASA)

-   (Source: Patrick Abbott, 1996: p. 160, Natural Disasters. Wm.
    C.Brown Publishers, Dubuque, IA. )

**PowerPoint 9.5** What is a Landslide?

-   (Source: USGS)

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

**PowerPoint 9.6** What is Subsidence?

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

-   (Source: www.mhhe.com)

**PowerPoint 9.7** What is a Dam Failure?

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

-   (Source: <http://simscience.org/cracks/movies/superman.mov>)

**PowerPoint 9.8** Earthquake Disasters

-   (Source: FEMA)

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

**PowerPoint 9.9** Volcano Disasters

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

**PowerPoint 9.10** Landslide Disasters

-   (Source: USGS)

-   (Source: Time)

**PowerPoint 9.11** Subsidence Disasters

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

-   (Source: USGS )

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

**PowerPoint 9.12** Dam Failure Disasters

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

**Lecture References:**

[^1]: Bates, R.L., and Jackson, J.A., 1987, Glossary of geology:
    American Geological Institute,

    Alexandria, Virginia, 788 p; and
    <http://volcano.und.nodak.edu/vwdocs/frequent_questions/top_101/Volcanoes/Volcanoes9.html>

[^2]: <http://geohazards.cr.usgs.gov/html_files/nlic/bludridge.htm>

[^3]: [http://wwwga.usgs.gov/edu/earthgwlandsubside.html]{.underline}

[^4]: <http://www.ncwater.org/Permits_and_Registration/Capacity_Use/Central_>

    [Coastal_Plain/landsub.php]{.underline}

[^5]: <http://www.ncwater.org/Permits_and_Registration/Capacity_Use/Central_>

    [Coastal_Plain/landsub.php]{.underline}

[^6]: Hallowell, Christopher.  Holding Back The Sea: The Struggle for
    America\'s Natural Legacy on

    the Gulf Coast. New York:  HarperCollins Publishers.  2001.

[^7]: [http://www.ncwater.org/About_DWR/Division_of_Water_Resources/Water_Allocation_Sectio](http://www.ncwater.org/About_DWR/Division_of_Water_Resources/Water_Allocation_Sectio%0DnGround_Water_Branch/Sinkhole/)

    [nGround_Water_Branch/Sinkhole/](http://www.ncwater.org/About_DWR/Division_of_Water_Resources/Water_Allocation_Sectio%0DnGround_Water_Branch/Sinkhole/)

[^8]: [http://www.ncwater.org/About_DWR/Division_of_Water_Resources/Water_Allocation_Sectio](http://www.ncwater.org/About_DWR/Division_of_Water_Resources/Water_Allocation_Sectio%0DnGround_Water_Branch/Sinkhole/)

    [nGround_Water_Branch/Sinkhole/](http://www.ncwater.org/About_DWR/Division_of_Water_Resources/Water_Allocation_Sectio%0DnGround_Water_Branch/Sinkhole/)

[^9]: [http://www.ncwater.org/About_DWR/Division_of_Water_Resources/Water_Allocation_Sectio](http://www.ncwater.org/About_DWR/Division_of_Water_Resources/Water_Allocation_Sectio%0DnGround_Water_Branch/Sinkhole/)

    [nGround_Water_Branch/Sinkhole/](http://www.ncwater.org/About_DWR/Division_of_Water_Resources/Water_Allocation_Sectio%0DnGround_Water_Branch/Sinkhole/)

[^10]: [http://www.dnr.state.oh.us/geosurvey/geo_fact/geo_f12.htm]{.underline}

[^11]: [http://www.dnr.state.oh.us/geosurvey/geo_fact/geo_f12.htm]{.underline}

[^12]: <http://www.ussdams.org/howdam.html>

[^13]: <http://www.fema.gov/fima/damsafe/idf_iiib.shtm>

[^14]: <http://www.fema.gov/fima/damsafe/idf_iiib.shtm>

[^15]: <http://dlr.enr.state.nc.us/damhazardclas.html>

[^16]: <http://www.fema.org/hazards/damsafety/>