Earthquakes What: Vibrations caused by the breaking of rock.
Where do earthquakes and volcanoes commonly occur? –Near plate boundaries (edges) Why? –Plate edges scrape together causing vibrations or where plates collide (oceanic and continental boundaries)
2004 Japan
December 2004, Sumatra
May 2008, China
Oakland, CA. The upper level of the two-level structure roadway has collapsed onto the lower level. The columns failed in response to the October 1989 Loma Prieta earthquake. 41 people were killed in the collapse.
9.0 Earthquake - Japan March 11, 2011
Damage to Humans 20,896 people killed, 4,647 missing, 5,314 injured, 130,927 displaced
Damage to Infrastructure Destroyed or damaged: 332,395 buildings, 2,126 roads, 56 bridges 26 railways
How does an earthquake occur? Plates shift position Vibrations disrupt the surrounding area
December 1954, Dixie Valley, NV (magnitude 6.8) The shack was relatively undamaged, despite being only a few meters from the two- to three-meter offset.
1989 Loma Prieta Fault, CA
7.0 Earthquake Haiti
Where do earthquakes occur? Along fault lines (cracks in the plates) and plate boundaries
Earthquakes may be deep underground or right at the surface (surface quakes cause more damage)
Earthquakes in the 7 days
NJ’s most recent quake November 23rd, 2012 Magnitude 2.2 Largest ever in NJ: –11/29/1783 –magnitude 5.3 –felt from NH to PA
8/23/ earthquake in VA Was felt from GA to ME and all the way out to Chicago akes/recenteqsww/Quakes/se a.php#summary
How is an Earthquake measured? Seismograph measures waves from an earthquake, the ground moves up and down but the weight with pen stays at the same level. e.com/watch?v=G bd1FcuLJLQ
Richter Scale Lines drawn by the pen determine magnitude (strength of quake) on Richter scale Scale goes from 0 & up, 6+ causes serious damage. 9.5 highest recorded quake (1960 – Chile)
Ancient Chinese Seismograph 132 AD, Zhang Heng -scientist A central pendulum swings with a quake, thus pulling on a dragon, which releases a ball into the toad’s mouth making a sound and marking the direction of the quake.
Damage Can crack buildings and roadways (billions of dollars in damages) Can trigger fires, landslides, and tsunamis Kills an average of 10,000 people a year China: over 87,000 people died in a 7.9 magnitude earthquake
Largest and Deadliest Earthquakes in the World Historical Earthquake List:
How to win a Nobel Prize Unanswered Questions about Earthquakes What starts or stops an earthquake? Do earthquakes “talk'' to each other? In other words, does one earthquake trigger the next earthquake? If so, how/why? Can earthquakes be predicted, and if so, how?
Earthquake Safety Knowing what to do before, during, and after an earthquake can help you and your family survive.
Build quake resistant buildings that move with the earth as it vibrates
Earthquake Safety Move or secure objects on high shelves
Earthquake Safety Stay indoors during the shaking and stand in a doorway or hide under a sturdy table away from windows and high objects. ontent/visualizations/es1005/es1005page01.cfm?cha pter_no=visualization
Drop, Cover, and Hold On!
After the quake Move outdoors to open areas quickly, watch for falling objects during aftershocks
Be Aware of Falling Debris
Earthquake Safety Tips BEFORE AN EARTHQUAKE: Have a disaster plan. Choose a safe place in every room. It’s best to get under a sturdy piece of furniture like a table or a desk where nothing can fall on you. Practice DROP, COVER AND HOLD ON! Drop under something sturdy, hold on, and protect your eyes by pressing your face against your arm. If you live in an earthquake prone area, bolt tall furniture to the wall and install strong latches to cupboards. Prepare a disaster supplies kit for your home and car. Include a first aid kit, canned food and a can opener, bottled water, battery- operated radio, flashlight, protective clothing and written instructions on how to turn off electricity, gas, and water. DURING AN EARTHQUAKE: DROP, COVER AND HOLD ON! Stay indoors until the shaking stops. Stay away from windows. If you’re in bed, hold on and stay there, protecting your head with a pillow. If you’re outdoors, find a clear spot away from buildings, trees and power lines. Then, drop to the ground. If you’re in a car, slow down and drive to a safe place. Stay in the car until the shaking stops. AFTER THE SHAKING STOPS: Check for injuries. Inspect your home for damage. Eliminate fire hazards, so turn off the gas if you think its leaking. Expect aftershocks. Each time you feel one, DROP, COVER AND HOLD ON.