I. Earth Structure
A. Inner Core ______(phase of matter); ______km diameter Mostly Ni and Fe Why is it solid even though it’s hot enough to melt any rock? ______
B. Outer Core ______/ Liquid; ______km thick Mostly Ni and Fe
C. Mantle ______km thick; Made of ______distinct layers: 1. Mesosphere Most of Mantle Non-Newtonian ______
2. Asthenosphere Liquid/ ______Mohorovicic Discontinuity (AKA: ______)- where seismic waves slow down
3. ______Lithosphere Broken Solid/ brittle
D. Crust Solid; broken into pieces called ______Mostly silica (______) rigid, with some flexibility
1. Two types of crust: a. ______Crust More dense of the two; about ______km thick Basaltic composition (______chemistry)
b. ______Crust
1 Less dense; more silica; about ______km thick Granitic composition (______chemistry)
II. Do Plates really move? Past/ Indirect Evidence of Plate ______
A. Distorted ______Layers
1. Folding & Tilting a. Principle of ______Horizontality
b. ______
c. Anticline
d. Geosyncline
B. ______Evidence 1. Marine ______found on the East Coast of South America and West Coast of Africa; unable to swim across the open ocean
2. ______What do corals need to survive? ______Why are they found in Wisconsin? ______
3. Ammonites & Belemnites in ______?
4. Marine ______on top of the Himalayas?
III. Present/ Direct ______of Plate Tectonics
A. ______
2 B. ______structures like fences, buildings, rivers
C. ______
IV. So the Plates move, How do they do it?
A. ______Currents in the ______
V. The Physics of Plate Tectonics
A. ______acting on the crust
1. ______Forces
a. Push or pull away from each other along a single line of motion
b. Divergent ______/ Rift
2. ______Forces
a. A push towards one another in a single line of motion
b. Convergent ______
Orogeny (______building)
1. Subduction ______
3. ______Forces
a. Forces that act in opposite directions along different lines of motion. Like a ______
b. ______sliding past one another
3 VI. So the Plates move, WHAT Happens now? Joints VS. Faults; Landforms; Earthquakes
A. Diastrophism the process by which the earth’s surface is ______by movement of the crust
B. Joints- are breaks or ______in bedrock along which NO movement has taken place
C. Faults- are breaks or fractures in bedrock along which movement ______taken place
1. Parts of a Fault
a. Footwall- the underlying surface of an inclined fault plane. Can act like a ______
b. Hanging Wall- the ______surface of an inclined fault plane
D. Types of Faults
1. ______a fault in which movement is parallel to the dip of the fault surface
FYI: ______is the angle and direction at which a plane is inclined from horizontal
a. ______Dip-Slip The hanging wall block has moved ______relative to the footwall
4 1. Caused mostly by ______forces
2. ______boundary
b. Reverse ______The hanging wall block has moved ______relative to the footwall
1. Caused mostly by ______
2. ______boundary
2. Lateral or ______A fault in which the fault block movement is parallel to the strike of the fault surfaces.
FYI: ______is the compass direction of a line by the intersection of an inclined plane with the horizontal plane
a. Mostly horizontal displacement, there is little or no vertical movement
b. Caused by ______forces
3. ______a fault having both strike- slip and dip-slip components, where plates move away from each other
a. Rifting and Sea Floor spreading result from this kind of fault.
b. Caused by ______forces
c. ______boundary
E. ______from Crustal Movement
5 1. ______defined as a mass of rock rising more than 600 meters above the surrounding land Relief: ______
a. Fold ______usually made mostly of sedimentary rock folded by compression. World’s tallest and most common mountains
1. Examples: Appalachians, Rockies, Alps, Himalayas
b. Fault-Block ______formed by a series of Normal Dip-Slip faults. Some of the greatest mountain Ranges 1. Examples: Sierra Nevada (California), Grand Teton (Wyoming), Wasatch (Utah)
F. When the Earth Shakes- ______
1. Can be caused by ______eruptions, but more often, faulting...
a. ______the movement of rock along a fault
b. ______Rebound occurs when tremendous pressure causes plates to move and the rock layers shake back and forth
1. ______Waves are waves of vibrations sent out in all directions from the focus
2. Where do Earthquakes start?
6 a. ______the point below the surface where the rocks break and move
b. ______the point on the surface, directly above the focus
3. How are Earthquakes measured?
a. ______is an instrument that detects, measures, and records the seismic waves produced by earthquakes
1. Operates on Newton’s ______Law of Motion
2. ______is the recorded information and looks like a zig zag line 4. Anatomy of a Wave
a. Crest the ______point on a wave
b. Trough the ______point on a wave
c. ______refers to the distance from the midpoint to the crest (or trough)
d. ______is the distance from the top of one crest to the top of the next or the distance between any successive identical part of the wave
e. Frequency often called ______, is the number of vibrations (cycles) per second
5. Types of Seismic Waves
a. ______WAVES: are waves which can travel through the body of the earth
7 1. ______Waves AKA P-Wave; are a type of Longitudinal wave. It causes back and forth particle motion; it follows the same direction as the energy transfer
a. They are a type of ______Wave (sound is this type)
b. Will travel through solid, liquid, and gas; must have a medium
c. Travels 7.8 –8.5 km per second in the Mantle… 7.2 km per second in ______crust... 3.5 km per second in continental crust
2. Secondary Waves AKA ______; With these waves, the particle motion is PERPENDICULAR to the direction of energy transfer
a. Transverse or Shear wave
b. Will travel only through ______
c. Travels 4 - 5 km per second
d. Moves side to side like a ______b. ______WAVES: move along the surface of the earth only
1. Surface Waves AKA ______Travel through the crust of the earth and attenuate (gradually disappear); Scientists have found that attenuation occurs more slowly in older rock (like the
8 eastern US, but more quickly in younger rock (western US)
a. They’re two main types: Love Waves and Raleigh Waves and they will travel only through ______
b. Travels less than 4 km per second
c. Moves up and down- causes most ______
9