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Test 1 Grades were “Fair”,
But ADD 10 POINTS to Your Score
(Don’t Count on it for Next Test!)
Grades After “Curve”
A/B = 88
B/C = 75
C/D = 62
D/F = 50
Evidence Why You Should Attend Class Regularly
# of Quizzes Taken Avg. Grade
3 69.23 71.05
2 60.36 59.88
1 58.46 57.16
0 56.17 59.33*
Quiz Attendance (a proxy for overall attendance) explains a full letter grade difference in Test 1 scores!
* Only 3 tests, so probably not Significant
1999 2000
Question of Time - Quiz
• If you plotted all of geologic time on a time line as long as the circumference of the Earth (25,000 mi or 40,000 km), what distance would represent 1 year?
• What distance would represent 75 years?
• What distance would represent 1 semester (4 months)?
The Whole Earth Time Line
• Circumference of the Earth is 25,000 mi (40,000 km)
• What distance would represent 1 year?
• Divide Distance by # of Years (4,600,000,000 yr)
• Easiest if We Use Metric Units
The Whole Earth Time Line
40,000 km / 4,600,000,000 yr =
distance represented by 1 year?
40,000,000 m / 4,600,000,000 yr =
4,000,000,000 cm / 4,600,000,000 yr =
0.87 cm / yr (0.34 inch / year)
The Whole Earth Time Line
0.87 cm / yr (0.34 inch / year)
X 75 yr = 65 cm (Lifetime = 25.7 inches)
X 0.33 yr = 0.29 cm (Semester = 0.7 inch)
Don’t Write This Down!
40,000,000,000,000 microns / (4,600,000,000 yr X 365 day/yr X 24 hr/day) = 0.99 micron / hour
This Lecture would be just over 1 micron long on the Whole Earth Time Line.
The paper you are writing on is about 100 microns thick
Fill out the landslide classification chart on the next slide:
Put a next to the two most deadly types of landslides worldwide.
Put a $ next to the most costly types of landslides in the Appalachians.
Put a Flying WV next to all landslides common in the Appalachian region
Which 2 States lead the US in Landslide damage per person?
Which 2 States lead the US in Total Landslide Damage?
What are the causes of Landslides?
This Quiz MUST BE TURNED IN TODAY (15 February, 2000) for any credit.
Geology 1 (Kite) Quiz 4 15 Feb 2000
“Soil”
Debris EarthRock
Typ
e of
Mot
ion
Fall
Topple
Flow
Avalanche
Landslides
Planar Slide
Rotational Slide
Last Time We Learned...Best Way to Break Rock:
Create Tension Within.
Cement Leached Out by CaCO3 Dissolution
• NOx or SO2 or CO2 + Water = Acid
Acid + Calcite = Ions in Solution
Cement Leached Out by CaCO3 Dissolution
• NOx or SO2 or CO2 + Water = Acid
– Acid + Calcite = Ions in Solution
Cement Leached Out by CaCO3 Dissolution
• NOx or SO2 or CO2 + Water = Acid
– Acid + Calcite = Ions in Solution
Role of Rock Type
• Bedding, Foliation, Joints = Avenues for Weathering
• Spheroidal Weathering .
Weathering “Front”
Weathering “Rind”
Speroidal Weathering
Role of Rock Type
• Porosity: % Void Space
• Permeability: Ability for Fluid to Penetrate
• Particle Size: –Volume v. Surface Area .
Weathering“Facies”
Strong P
hysic
al
Strong P
hysic
al
StrongChemical
VeryVerySlightSlight
Rainfall
Tem
p
SOILS
• Soils (Engineering): Unconsolidated Earthy Materials
• Soils (Soil Science, Geology) Unconsolidated Earthy Materials that Support Life
Transported Soils vs. Residual Soils
Wind Deposits in Situ Weathering
Stream Deposits of Bedrock
Glacier Deposits
Beach Deposits
Soil-Forming Factors
• Climate
• Organisms
• Relief (Topography)
• Parent Material
• Time .
Soil Orders - USASoils Vary a Great Deal From Region to Region
Ye Olde Soil Horizons
A - Topsoil
B - Subsoil
C - Unaltered Unconsolidated Material .
Ye Olde Soil Horizons
A - Topsoil
B - Subsoil
C - Unaltered Unconsolidated Material
Modern Soil Horizons
O - Organic Mat at the Surface
A - Topsoil: Removal of Clay, Iron, etc.
B - Subsoil: Accumulation of Clay, Iron,
Humus, etc.
C - Barely Altered Unconsolidated Material
R - Solid Bedrock .
Modern Soil Horizons
A
B
C
O
R
Mass Movement = Mass Wasting
=colluvial processes
=slope processes
=slope failures
=LANDSLIDES
Strength of Slope = Cohesion + Strength of Material
• Strength of Material Varies with Moisture
• Poor Drainage: Slope Instability .
Angle of Internal Friction
Stable Angle of Slope for a Material .
Angle of Internal Friction
• Qtz Sandstone = 90o
Angle of Internal Friction
Shale = 45o
or 1:1 Slope
Angle of Internal Friction
• Old Landslide Deposits = 5-25o
Angle of Internal Friction
• Clay = 1-15o
Shear Strength/Shear Stress
=Factor of Safety
“Soil”
Debris EarthRock
Typ
e of
Mot
ion
Fall
Topple
Planar Slide
Rotational Slide
Flow
Avalanche
Rock Fall Debris Fall Earth Fall
Rock Topple Debris Topple Earth Topple
Rock Slide Debris Slide Earth Slide
Rock Slump Debris Slump Earth Slump
Rock Flow Debris Flow Earth Flow
Rock Avalanche
Debris Avalanche
Earth Avalanche
Landslides
Basic Landslide Classification
Material
“Soil”
Debris EarthRock
Typ
e of
Mot
ion
Material
Soil: Unconsolidated Material
Debris: >20 % Big Stuff (>2 mm)
Earth: <20 % Big Stuff (>2 mm)
Rock: Bedrock
“Soil”
Debris EarthRock
Typ
e o
f M
oti
on
Fall
Topple
Planar Slide
Rotational Slide
Flow
Avalanche
Landslides
Types of Landslides
“Soil”
Debris EarthRock
Typ
e of
Mot
ion
Fall
Topple
Planar Slide
Rotational Slide
Flow
Avalanche
Rock Fall Debris Fall Earth Fall
Rock Topple Debris Topple Earth Topple
Rock Slide Debris Slide Earth Slide
Rock Slump Debris Slump Earth Slump
Rock Flow Debris Flow Earth Flow
Rock Avalanche Debris Avalanche Earth Avalanche
Landslides
Fall
Topple
FallTopple
Landslides
Landslides - Topple
Fall
Landslides - Rock Fall
70 ton Boulder: “Mon” Blvd., 10 March 1994
“Soil”
Debris EarthRock
Typ
e of
Mot
ion
Fall
Topple
Planar Slide
Rotational Slide
Flow
Avalanche
Rock Fall Debris Fall Earth Fall
Rock Topple Debris Topple Earth Topple
Rock Slide Debris Slide Earth Slide
Rock Slump Debris Slump Earth Slump
Rock Flow Debris Flow Earth Flow
Rock Avalanche Debris Avalanche Earth Avalanche
Landslides
Planar Slide
Rotational Slide
Planar Slide = “Slide”
Rotational Slide = “Slump”
Landslides
Planar Slide = “Slide”
Rotational Slide = “Slump”
Landslides
Planar Slide = “Slide”
Rotational Slide = “Slump”
Landslides
“Slump”
Slump in California
“Slump”
La Conchita, CaliforniaSlump
Slump, La Concita, California
Hurricane Georges (1998)Slump, Puerto Rico
Seattle Shoreline
Where Would You Be Safe?
“Soil”
Debris EarthRock
Typ
e of
Mot
ion
Fall
Topple
Planar Slide
Rotational Slide
Flow
Avalanche
Rock Fall Debris Fall Earth Fall
Rock Topple Debris Topple Earth Topple
Rock Slide Debris Slide Earth Slide
Rock Slump Debris Slump Earth Slump
Rock Flow Debris Flow Earth Flow
Rock Avalanche
Debris Avalanche
Earth Avalanche
Landslides
Flow
Avalanche
La Guaira, Venezuela: Dec 1999
La Guaira, Venezuela: Dec 1999 15,000 to 100,000 Dead
November 1985Debris Flow Track,
Twin Run, Pendleton Co., WV
Superelevation of Debris Flow, Twin Run
Kanawha City Debris Flow: 3 Dead 1973
Mt. St. Helens Lahar, 1982
Lahar (= Debris Flow &Debris Avalanche)Hazard in the Seattle Area
This Image: http://vulcan.wr.usgs.gov/Imgs/Jpg/Rainier/Outreach/screen_poster_lahar_haz.jpg
Mount Rainier, WA
Seattle
Mt. Huascaran, Peru, 1970
17,000 dead>300 km/h
How Fast?
Armero, Colombia, near Nevado del Ruiz Volcano, Nov. 1985
23,000 Dead
“Soil”
Debris EarthRock
Typ
e of
Mot
ion
Fall
Topple
Planar Slide
Rotational Slide
Flow
Avalanche
Rock Fall Debris Fall Earth Fall
Rock Topple Debris Topple Earth Topple
Rock Slide Debris Slide Earth Slide
Rock Slump Debris Slump Earth Slump
Rock Flow Debris Flow Earth Flow
Rock Avalanche
Debris Avalanche
Earth Avalanche
Landslides
Creep Start Here 17 Feb
Creep
Creep
Creep
Creep
Creep
Landslides by U.S. Region
• California 40% of U.S. damage
• West Virginia 13% of U.S. damage
U.S. Landslide Risk
WV Has 1st or 2nd Highest Landslide Damage Per Capita
• $100-300 /person/yr
• About Same as UTAH
Main Regional Problems Are
• Road Failures
• Building Damage
• Construction Cost Over-Runs
Regional Causes of Landslides
• Steep Topography – Mountains – Incision by Rivers
• Materials
– Red Shales - Expansive Clays
• Stupid or Ignorant People– Oversteepening of Slopes– w/o Geotechnical Consulting
Solutions to Landslide Problems
• Don’t Be Stupid
• Seek Geotechnical Help From Geologists or Civil Engineers