How and where Earthquakes form http www thirteen

How and where Earthquakes form http: //www. thirteen. org/programs/nova/deadliest-earthquakes/ NOVA: Deadliest EQ’s http: //earthquake. usgs. gov/earthquakes/map/ USGS real-time EQ’s

An earthquake is a shaking “quaking” of the Earth caused by earth Nuclear bomb explosion Cavern collapse volcanic eruption meteor impact

Earthquakes are caused by the motion along plate boundaries

Earthquake Scavenger Hunt Find the following at: http: //earthquake. usgs. gov/ 1. 2. 3. 4. 5. 6. 7. 8. Largest earthquake in the world, ever. Largest earthquake in U. S. Country with the most earthquakes. Where are most earthquakes located? Which plate boundary has the largest, deepest EQs? Where was the most recent EQ? (today) Where is the New Madrid fault zone? What causes a tsunami? How high can they get?

Where do most of the world’s earthquakes occur? http: //www. classzone. com/books/earth_science/terc/content/investigations/es 1001 page 02. cfm

Earthquakes are… Vibration of Earth produced by the rapid release of… ENERGY Energy in the form of Mechanical waves that move through Earth’s crustal rock https: //www. youtube. com/watch? v=Yi 3 LW 5 ri. Hfc

Enough energy to flatten entire cities in less than a minute!

Earthquakes are caused by STRAIN that builds up between plates along a fault. A FAULT : where the opposing (shearing) motion between two lithospheric plates moving in opposite direction FRICTION between the rock surfaces prevent the plates from sliding easily.

San Andreas Fault A break in the lithospheric crust along which movement occurs. http: //www. youtube. com/watch? v=Zx. PTLmg 0 ZCw&feature=relat ed&safety_mode=true&persist_safety_mode=1 (3 min)

Earthquakes occur at faults as plates move Laterally: strike-slip fault Down: normal fault Up: thrust fault

New Madrid Fault zone

Illinois has many faults and fractures, most in southern Illinois

Focus: the point in the earth’s crust that moves /shifts Epicenter: the location on the earth’s surface above the focus.

Epicenter: the location on the earth’s surface above the focus. The waves spread out from the epicenter

Distance the Fault Block traveled (cm) Number of pieces of spaghetti Trial #1 Trial #2 Trial #3 Average Ratio 1 1: 1 2 3 Ratio: Compare (divide) distance of 2 and 3 spaghettis to your original distance for 1 spaghetti

Convergent boundary At convergent boundaries the ocean plate plunges under the continental plate. They scrape and produce large amounts of friction and deep earthquakes.

Do the Strike-slip Fault Investigation

Elastic Rebound Theory

Stress and strain builds along faults Friction prevents the plates from moving easily

Elastic rebound

https: //www. youtube. com/watch? x-yt-ts=1421914688&v=-5 Bg. KKutx. Bs&x-ytcl=84503534&feature=player_embedded

EQ prediction • https: //www. youtube. com/watch? v=g. FBqpi. Kccs • http: //www. yourarticlelibrary. com/earthqua ke/earthquakes-prediction-9 -methods-topredict-earthquake/13915/

Unit: ___7_______ PHENOMENON: What EVIDENCE do you have? Topic: ___Earthquakes_______ OBJECTS: Define the system. What objects are interacting? MOTION: Describe the MOTION that in the model that explains your observations

PHENOMENON: What did you observe? What EVIDENCE do you have? Haiti EQ was total destruction and 200, 00 deaths in 60 seconds Largest EQ: Chili (9. 4) Alaska (9. 2) Internet investigation ES 1001 “How are Earthquakes Related to Plate Tectonics? At www. classzone. com Strike-slip fault investigation: -The rubber bands stretch and the block doesn’t move, until it stretches too far then the block ‘jerks’ forward. This occurs repeatedly. Spaghetti strike-slip fault lab -The more pieces of spaghetti, the more friction to overcome and the more distance the plate moves OBJECTS: Define the system. What’s interacting? Video clip of Haiti EQ The rock along Earth’ plate boundaries MOTION: Describe the MOTION in the model that explains your observations Earthquakes occur due to movements along faults at plate boundaries. Most earthquakes occur in zones around the Pacific Ocean (ring of fire) or the ocean ridge system that closely correlated with plate boundaries Large, deep EQs occur at convergent boundary where the dense ocean plate subducts deep under continent into mantle Most frequent EQ are magnitude 1 -3 are at divergent boundaries in the ocean ridges. Earthquakes are vibration of Earth produced by the rapid release of stored elastic potential energy Rocks "spring back" in a phenomenon called elastic rebound occurs as rock’s elastically returns to its original shape The focus—the place within Earth where earthquake waves originate Epicenter is the point on the surface directly above the focus

The story so far… • Two tectonic plates do not flow past each other smoothly, but rather the faults that form their boundaries tend to stick or lock up for years at a time due to friction. • Each year the portions of plates near locked faults move slowly a few millimeters and deform elastically. • The more the plates are stretch and deformed, the greater the force is on the fault (shear stress). • Eventually the force is sufficient to overcome the friction and make the plates break free of one another • The elastic energy that has been stored up is released and ground vibrations. (seismic waves). • This process of faulting is called stick-slip or elastic rebound.