1. Monday December 5, 2016
Notebook, Pencil

2. The Focus and Epicenter of an Earthquake
Focus - The point within (inside) Earth where faulting/breaking of rock begins or hypocenter
Epicenter – The point directly above the focus (where rocks break and move) on the surface is the epicenter

3. Waves of energy released as vibrations caused by an earthquake
Seismic Waves
Waves of energy released as vibrations caused by an earthquake

4. Seismic Waves Primary Waves (P waves) Secondary Waves (S waves)
Fastest (arrive first)
Travel through liquids & solids
Push and pull waves
Secondary Waves (S waves)
Arrive second
Cannot travel through liquid

5. Seismic Waves Surface Waves Move along the Earth’s surface
Not through the interior
Make the ground roll up and down
Largest movements
Cause the most damage

6. Seismographs
Seismograph – is an instrument that constantly records ground movements
Separate seismographs record side-to-side movements and up-and–down movements
When the ground moves in an earthquake, the heavy weight moves and the pen attached to the weight records the movements
Turn to page 57 in your book

7. Tuesday December 6, 2016
Notebook, Pencil

8. Supplies for next week!!
Liquid glue
Baking soda
Vinegar
newspaper

9. Magnitude
Richter Scale - Scale developed in California during the 1930’s by scientist Charles Richter and Beno Gutenberg
Based on a scale of 0-10
8 or higher is considered extremely powerful
Magnitude is based on how fast the ground moves at a seismic station
Moment Magnitude Scale – based on the total amounts of energy released by earthquakes
New more accurate scale used (used in our book to measure magnitude)
For each scale, an increase of one whole number indicates an increase of 32 times as much energy than the previous number
Example - magnitude 5 EQ releases 32 times more energy than a magnitude 4 EQ

12. Aftershock
A smaller EQ that follows a more powerful EQ in the same area
Other damage – broken pipes and fires can cause great damage after an EQ
The moving of the ground usually does not injure people – they are injured/killed by building collapsing on them

13. Liquefaction
Liquefaction – a process in which shaking of the ground causes soil to act like a liquid
Soil becomes like a thick soup
Occurs in areas where the ground is made up of loose sand and silt and contains large amounts of water

14. Tsunami
Tsunami – a wave of water triggered by an earthquake, volcanic eruption or landslide
Sometimes called tidal waves
Can be several waves that arrive hours apart

15. Predicting Earthquakes
Can only give long term predictions based on the EQ risk of an area
Scientists monitor stress along faults
Tilts or changes in the elevation of the ground
Slow movements or stretching in rock
The development of small cracks in the ground

16. Earthquake –Resistant Buildings
Base-isolators – placed between a building and its foundation. They are flexible layers that are stacked
Open space/moat – open space give the building room to shake
Shear walls – add strength to the structure with steel supports
Cross braces – X shaped braces help building keep its shape during shaking

17. Wednesday December 7, 2016 Wednesday December 7, 2016 Notebook, pencil

18. Volcanoes Wednesday December 7, 2016
Volcano – is an opening in the Earth’s crust through which molten rock, rock fragments, and hot gases erupt.
Magma – molten rock under the Earth’s surface
Lava – magma that has reached Earth’s surface
Wednesday December 7, 2016
Notebook, Pencil

19. Volcano Structure

20. Pyroclastic Flow A dense cloud of superhot gases and
rock fragments that races downhill.
Ash – volcanic ash is made up of rock fragments less than 2 millimeters in diameter
Cinders – cinders contain holes and tunnels left by escaping gas
Block – large fragments are called blocks or bombs

21. Volcanoes Most volcanoes form along plate boundaries
Where oceanic plates sinks beneath another plate – subduction zones
Where plates are pulling apart, allowing magma to rise from the mantle
Great Rift Valley in Africa
Mid Atlantic Ridge
Form over Hot Spots
80% are along the subduction zones of the Ring of Fire

22. Types of Volcanoes Shield Volcano – is shaped like a broad, flat dome
Build up from many eruptions of lava that is relatively low in silica
Flows easy and spreads out in thin layers

23. Types of Volcanoes Cinder Cone –
Is a steep, cone-shaped hill formed by the eruption of cinders and other rock fragments that pile up around a single crater
Cinders from gas rich magma erupts

24. Types of Volcanoes Composite Volcano –
Is a cone shaped volcano build up of layers of lava and layers of rock fragments
Its magma is high in silica making the magma thick
Steep at the top and flattens at the bottom
Have VERY violent eruptions
Expanding gases trapped rising magma tend to cause explosions
Hardened lava from earlier eruptions often plugs opening

25. Scientists Monitor Volcanoes
To predict when future eruptions will occur
Volcanoes can go 100’s of years between eruptions
Monitor magma movement under ground
Earthquakes
Changes in the tilt of the ground
Temperatures at openings, springs and lakes
Amounts and types of gases given off
Mount St. Helens

26. Thursday December 8, 2016
Notebook, Pencil

27. Friday December 9, 2016
Notebook, Pencil