Topographical maps
http://reynolds.asu.edu/topo_gallery/topo_gallery.htm
cliff
Mountain
Complex valley
Contour maps how to read
• http://www.compassdude.com/topographicmaps.shtml
• http://adventure.howstuffworks.com/outdoor
-activities/hiking/how-to-read-a-topographicmap2.htm
Earth Quakes
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Video 3 national geographic earthquake 101
Video of earth quake you tube
Video 2 Japan photos
Video 3
What do you know about earth
quakes?
Your Assignment:
• Invent a specific quake and imagine yourself in
it.
• Open the template I have sent you on Phy Sci
resources.
• You are going to write about your earthquake
from three view points; News reporter,
scientists, and eyewitness.
Earth Quake Causes
• They occur in Zones that coincide with the
edges of the Lithospheric plates. (crust and
upper section of the mantle)
• Deformation of the earths crust:
– Compression
– Tension; stretched
– Shear; move opposite directions
– Torsion; twisted
Earthquake waves
• Focus; the point of origin
• Epicenter; on the surface directly above the
focus.
http://cse.ssl.berkeley.edu/lessons/indiv/davis/inprogress/QuakesEng3.html
Earthquake waves
BODY WAVES
• P waves
• S waves
P waves
• Primary waves.
• The rock vibrates in the same direction the
wave is moving.
• Travel the fastest through rocks
S waves
• Shear waves or Secondary waves
• Particles move perpendicular to the direction
of wave travel
Surface waves
• Can be like S waves
• Like Ocean waves with rolling motion
• Cause the most Damage to structures
Types of Faults
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Normal Fault: Tension forces
Reverse fault; Compression forces
Strike slip fault: Shearing forces
animations
Normal fault
Measuring earthquake strength
• Richter Scale and Modified Mercalli Scale
• Measured by a seismograph
• You must know the difference
between the types of scales.
Richter Scale
• Based on the measurements of amplitude of
seismic waves
Modified Mercalli Scale
• Measures the amount of structural and
geological damage the earthquake causes or
its intensity.
Richter scale
What happens to buildings in an Earth
quake?
• They sway from the ground floor up.
• Taller buildings are more flexible and sway
more. Shorter buildings shake to pieces.
Seismic Safe Structures
• A structure that is resistant to the vibrations
from earthquakes. It will still be standing!!!!!
• The building and foundation need to be built
to resist the sideways motion (load). Diagonal
bracing.
• Allow the structure to move as a unit and not
shake.
• Dampers that can absorb the motion so it is
not transferred to the building.
Building material that absorbs motion. Large
bearings ( rubber or springs) in the foundation
Make structures that can bend.
Strengthening the foundation and securing the
building to the foundation
• Diaphram
• Diaphragms are horizontal resistance elements, generally
floors and roofs, that transfer the lateral forces between
the vertical resistance elements (shear walls or frames).
Basically, a diaphragm acts as a horizontal I-beam. That is,
the diaphragm itself acts as the web of the beam and its
edges act as flanges. (See figure 1)
http://mceer.buffalo.edu/infoservice/reference_services/basicseqdesign.asp
• Shear wall
Shear walls are vertical walls that are designed
to receive lateral forces from diaphragms and
transmit them to the ground. The forces in
these walls are predominantly shear forces in
which the fibers within the wall try to slide
past one another.
• Braced Frame
• Moment Resistant Frame
Volcanoes and Earthquakes
Volcanoes
• Molten rock beneath the surface called
Magma rises through the crust.
• This forms Lava on the surface.
• Form at Subduction Zones both Continental
and Oceanic
• Magma is below the surface of the crust
• Lava is the molten rock on the surface.
Ring of Fire
Types of Volcanoes
• Cinder Cone: large fragments of solid
materials
Shield Volcanoes
• Abundant lava flows;
• broad and flat shape that is made up of layers
of lava flows.
Composite Volcanoes
• Include pyroclastic materials and lava flows.
Usually along Convergent plate boundaries
• Water and silica forced down to mix at the
boundary produce an especially viscous
magma.
Mount Rainer in WA
http://www.landforms.eu/lothian/volcanic%20neck.htm
• Volcanic neck
• Definition: a hill resulting from differential weathering
and erosion between the former feeder tube of a
volcano and its surrounding rocks.
• A volcanic plug, also called a volcanic neck or lava neck,
is a volcanic landform created when lava hardens
within a vent on an active volcano. When forming, a
plug can cause an extreme build-up of pressure if
volatile-charged magma is trapped beneath it, and this
can sometimes lead to an explosive eruption. If a plug
is preserved, erosion may remove the surrounding rock
while the erosion-resistant plug remains, producing a
distinctive landform.
Ship Rock
Devils Tower
Volcanic dike
• Dikes are imaginable as the veins of a volcano,
the pathways of rising magma. A dike is called
a -usually more or less vertical- flat, sheet-like
magma body that cuts unconformingly
through older rocks or sediments. Most dikes
can be described as fractures into which
magma intrudes or from which they might
erupt.
The End