Chapter 10 Tectonics, Earthquakes & Volcanism Flashcards Preview

GEOG 300 > Chapter 10 Tectonics, Earthquakes & Volcanism > Flashcards

Flashcards in Chapter 10 Tectonics, Earthquakes & Volcanism Deck (28)
Loading flashcards...
1
Q

Topography

A

Studies shapes and features of Earth. “The Lay of the land”

2
Q

Earth’s Topography

Three orders of relief

A

1st Continents/Oceans
2nd Mountain ranges, plains,
lowlands, mid-ocean ridges
3rd Mountain, hill, cliff, valley

3
Q

Faults

A

Large scale fracture in lithosphere
Where movement occurs
Occurs at plate boundaries or within plates
Some faults active, others not

4
Q

Normal Faults

A

Cliff-steep landscapes

5
Q

Reverse/Thrust Faults

A

Creates mountains, volcanoes, earthquakes

6
Q

Strike-Slip Faults

A

Result from side-to-side motion

7
Q

Orogenesis

A

Birth of Mountains

8
Q

Oceanic and Continental Plates

A

Creates Pacific Coast Mountain Range compression causes crust to uplift and buckle.
Ex: Pacific Coast

9
Q

Oceanic and Oceanic Plates

A

Creates volcanic islands by creating a deep ocean trench forcing magma upward.
Ex: Southwestern Pacific to
Western Pacific

10
Q

Continental and Continental

Plates

A

Both plates are light forming large mountain ranges.

Ex: Himalayas

11
Q

When Earthquakes occur what happens?

A

Release of built-up energy caused by stress in rock
Occur when new faults are formed
Occur when existing faults move

12
Q

Focus

A

Location at which earthquake originates inside earth

13
Q

Epicenter

A

Location at the surface of the Earth that is directly above the focus

14
Q

Foreshock

A

Earthquake before main shock

Important for large earthquake forecasting

15
Q

Aftershock

A

Earthquake that occurs after main shock

Shares general area of epicenter

16
Q

Magnitude

A

The amount of ground shaking

17
Q

Earthquake Measurement

A

Moment Magnitude Scale
Formerly the Richter Scale
Each number represents 10 times increase of ground shaking

18
Q

Liquefaction

A

The conversion of unconsolidated

material into liquid state caused by movement, pressure, and presence of water

19
Q

San Francisco 1906

A
Most famous U.S. quake
- April 18th at 5:12am
- 7.9 magnitude
- 450-700 dead
- Fires caused more damage than quake
itself
20
Q

Tsunami

A

Seismic Sea Wave (not tidal)

- Caused by earthquakes at sea

21
Q

Volcanoes

A

Four types

  • Composite (Stratovolcano)
  • Shield
  • Cinder Cone
  • Dome
22
Q

Volcano Activity Categories

A
•Active
  - Erupted within recorded history
• Dormant
   - Evidence of activity, but not observed
• Extinct
   - No sign of activity
   - Severe erosion, well-developed soil, 
      lush vegetation
23
Q

Composite (Stratovolcano)

A

Largest Volcano
Violent, explosive eruptions
Layer of lava and tephra
Examples: Mt. St. Helen and Mt. Shasta

24
Q

Shield

A
Very Wide
Circular Exterior
Lava flows slowly in all directions
Effusive eruptions
Example: Hawaiian Islands
25
Q

Cinder Cone

A
Most Common type of volcano
Small, cone shaped hill
Low in elevation
Top formed cinders during eruption
Emits pyroclastic flow/cinder rock
Example: Northern Arizona
26
Q

Dome

A
Small to medium sized
Explosive eruptions
Composed of felstic lava
Cooling of lava creates cylinder shape
Slope created from erosion
Examples: Lassen Peak, Mono-Inyo Craters
27
Q

Earthquakes occur when

A

Faults form and move

28
Q

The San Andreas Fault is an example of

A

Strike-Slip fault