warm up 9/29 1) what is convection flow and how does this lead to movement of lithospheric plates?...
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Warm up 9/29Warm up 9/291)1) What is convection flow and how does this What is convection flow and how does this
lead to movement of lithospheric plates?lead to movement of lithospheric plates?
2)2) What creates convection flow? What creates convection flow?
3)3) Draw a diagram of convection flow. Label the Draw a diagram of convection flow. Label the parts in your diagram.parts in your diagram.
11stst block, 9/30 block, 9/30
1.1. Finish reading the Haiti Earthquake Finish reading the Haiti Earthquake article and answering the questionsarticle and answering the questions
2.2. Hand it in the black box when Hand it in the black box when finished.finished.
3.3. You have 20 minutesYou have 20 minutes
Warm-up 9/30, 4Warm-up 9/30, 4thth block block
List the three types of seismic waves List the three types of seismic waves and describe one characteristic of and describe one characteristic of each type.each type.
Put your name on this sheet of paper Put your name on this sheet of paper and hand it in the black box up front.and hand it in the black box up front.
ObjectivesObjectives
First…table of contents!First…table of contents!
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Date Title Page9/22/14 Convection currents
and Plate Tectonics Guided Notes with Vocabulary
1
9/22/14 Plate Boundaries Diagram
2
9/22/14 Tectonic Plates Activity Sheet
3
Unit 2: Earthquakes & Plate Tectonics
9/29/2014 Volcanoes and Earthquake Anatomy Notes
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VolcanoesVolcanoes
A volcano is mountain formed of A volcano is mountain formed of lava and/or pyroclastic materiallava and/or pyroclastic material
Convergent boundariesConvergent boundaries
They can be caused by convergent They can be caused by convergent boundaries, in which plate boundaries, in which plate subduction forces magma to the subduction forces magma to the surface.surface.
Divergent BoundariesDivergent Boundaries
Volcanoes are also formed by Volcanoes are also formed by divergent boundaries because as divergent boundaries because as plates move apart, magma rises to plates move apart, magma rises to fill the gap.fill the gap.
Magma vs. LavaMagma vs. Lava
Magma is molten rock found beneath Magma is molten rock found beneath the Earth’s crustthe Earth’s crust
Lava is molten that reaches the Lava is molten that reaches the surface and erupts from the volcanosurface and erupts from the volcano
Effects of volcanoesEffects of volcanoes
1) Lahar- material that flows down the 1) Lahar- material that flows down the volcano. It is a mixture of water and volcano. It is a mixture of water and rock fragmentsrock fragments
Effects of volcanoesEffects of volcanoes
2) Volcanic ash: fragments of material 2) Volcanic ash: fragments of material that explode from the erupting volcanothat explode from the erupting volcano
What happened in Japan?What happened in Japan?
Tsunami hitting the coast:Tsunami hitting the coast:
http://www.youtube.com/watch?http://www.youtube.com/watch?v=Yl08jK4ci2gv=Yl08jK4ci2g
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The red dots are locations of Earthquakes. Make an The red dots are locations of Earthquakes. Make an observation and an inference about this map.observation and an inference about this map.
San Francisco 1989San Francisco 1989
SF Earthquake 1989 (longer)SF Earthquake 1989 (longer)
What is a focus?What is a focus?
The point beneath the The point beneath the Earth’s surface where Earth’s surface where
rock under stress breaks rock under stress breaks to cause an earthquake.to cause an earthquake.
What is an What is an epicenter?epicenter?
The point on the The point on the surface directly surface directly above the focus.above the focus.
The farther the distance The farther the distance between the focus and the between the focus and the epicenter, the weaker the epicenter, the weaker the earthquake. Therefore, earthquake. Therefore, the closer the focus is to the closer the focus is to the surface, the stronger the surface, the stronger
the earthquake.the earthquake.
Distance from Focus to Epicenter
What is a fault?What is a fault?
It is the break in the crust where the earthquake began, between two blocks of rock that have moved past each other.
3 Types of Faults3 Types of Faults
Normal Reverse Strike-slip
When the hanging wall drops down.
When hanging wall moves up.
Walls move sideways
Creates forces that pull the sides apart
Creates compressional forces.
Horizontal forces
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Quick ReviewQuick Review1)What causes an
earthquake?2)Label the fault,
epicenter, and focus in the picture to the right.A =B =C =
ab
c
What are seismic What are seismic waves?waves?
Seismic waves are the Seismic waves are the waves (vibrations) waves (vibrations)
caused by caused by earthquakes earthquakes
During an earthquake, During an earthquake, vibrations called seismic vibrations called seismic
wave move out from the focus wave move out from the focus in all directions similar to the in all directions similar to the ripples created by a pebble in ripples created by a pebble in
a pond.a pond.
Seismic waves carry the energy Seismic waves carry the energy of an earthquake away from the of an earthquake away from the
focus, through the Earth’s focus, through the Earth’s interior, and across the surface.interior, and across the surface.
What are the three types What are the three types of seismic waves?of seismic waves?
Primary waves Primary waves
(P waves)(P waves) Secondary Waves Secondary Waves
(S waves)(S waves) Surface waves (L waves) Surface waves (L waves)
Describe a P wave.Describe a P wave. Travel the fastestTravel the fastest Travel solids, liquids, and gasesTravel solids, liquids, and gases Move through the Earth at different Move through the Earth at different
speeds, depending on the densityspeeds, depending on the density Called “push-pull” waves Called “push-pull” waves
(compress and expand the ground (compress and expand the ground like an accordion)like an accordion)
Describe an S wave.Describe an S wave.
Arrive at a given point after the Arrive at a given point after the
P wavesP waves Travel only through solidsTravel only through solids Move through solids at different Move through solids at different
speeds depending on the densityspeeds depending on the density Cause rock particles to move from Cause rock particles to move from
side to side & up and downside to side & up and down
Describe a L wave.Describe a L wave.
Slowest of the seismic wavesSlowest of the seismic waves Move along the Earth’s Move along the Earth’s
surface like waves travel in surface like waves travel in the oceanthe ocean
Cause most of the damage Cause most of the damage during an earthquakeduring an earthquake
When the P & S When the P & S waves reach the waves reach the
surface, they move surface, they move more slowly creating more slowly creating
the most severe the most severe ground movements.ground movements.
What do scientists use to What do scientists use to detect and measure detect and measure
earthquakes?earthquakes?
SeismographsSeismographs are used by are used by scientist to detect, measure & scientist to detect, measure &
record the vibrations of record the vibrations of seismic waves. seismic waves.
An earthquake’s magnitude is a measurement of its strength based on seismic waves and movement along faults.
https://www.youtube.com/watch?v=Gbd1FcuLJLQ
Seismic Wave DemoSeismic Wave Demo
EQ & Seismic Wave FoldableEQ & Seismic Wave Foldable
Let’s Fold and Label togetherLet’s Fold and Label together The directions for the inside of the The directions for the inside of the
foldable is at your stationfoldable is at your station
What are 3 What are 3 rating scales rating scales
used to used to measure an measure an earthquake?earthquake?
Mercalli scale –Mercalli scale –
This scale rates This scale rates earthquakes by earthquakes by
describing their effects on describing their effects on people, buildings, and the people, buildings, and the
land surface in a given land surface in a given location. location.
Richter scaleRichter scale
This scale rates This scale rates earthquakes according to earthquakes according to the size of seismic waves the size of seismic waves
as measured by the as measured by the seismograph. seismograph.
Moment Magnitude Moment Magnitude scalescale
This scale rates earthquakes by This scale rates earthquakes by estimating the total energy estimating the total energy they release. The moment they release. The moment
magnitude scale can be used magnitude scale can be used to measure earthquakes of to measure earthquakes of
all sizes, near or far!all sizes, near or far!
How do scientists How do scientists determine the determine the location of an location of an earthquake’s earthquake’s epicenter?epicenter?
When an earthquake When an earthquake strikes, P waves are the strikes, P waves are the first to arrive at a first to arrive at a seismograph followed by seismograph followed by the S waves.the S waves.
The farther away the The farther away the epicenter is, the greater the epicenter is, the greater the difference between the two difference between the two arrival times.arrival times.
This difference in time tells This difference in time tells scientists how far the scientists how far the
seismograph is from the seismograph is from the epicenter. This information epicenter. This information is then used to plot a circle is then used to plot a circle
on a map.on a map.
The circle shows the The circle shows the distance from one distance from one
seismograph station to all seismograph station to all points where the epicenter points where the epicenter
could be located.could be located.
.
To determine the exact To determine the exact location of the epicenter, at location of the epicenter, at least THREE stations need to least THREE stations need to find their distance from the find their distance from the epicenter and draw a circle epicenter and draw a circle on a mapon a map
The The single pointsingle point where the 3 circles where the 3 circles
intersect is the intersect is the location of the location of the earthquake’s earthquake’s
epicenter.epicenter.
VideoVideo
https://www.youtube.com/watch?https://www.youtube.com/watch?v=My5ootSNbakv=My5ootSNbak