1. Earthquake and Faults
- 1. EARTHQUAKES and FAULTS Prepared by: Louie Jane T. Eleccion
- 2. Objectives •Recall the different layers/parts of the Earth. •Discuss convection currents within the earth’s mantle, causing plate movements. •Define and recognize faults, and describe its movements. •Infer that movement of faults generate earthquake.
- 5. CONVECTION CURRENTS • Convection is the movement of liquid material that is heated from underneath, rises and cools on top.
- 6. EARTHQUAKE • The shaking of the Earth’s surface.
- 7. EPICENTER • The point on earth’s surface directly above the focus.
- 8. FAULT PLANE • Breaking surface underground. FAULT SCARP • When the fault plane is exposed above ground.
- 9. FAULT LINE
- 11. FAULT • It is a fracture or break in Earth’s crust where earthquakes are most likely to occur repeatedly. • It forms when the rocks of the crust are compressed or stretched. • They break along the areas where they are weak. • These breaks are called fault zones if there are many faults spread over the area.
- 14. 3 TYPES OF FAULTS •NORMAL FAULT •REVERSE FAULT •STRIKE-SLIP FAULT
- 18. FAULT MOVEMENTS • Faults move due to stress, a force exerted when an object presses on, pulls on, or pushes against another object. 3 Types of Stress • Tensional • Compressional • Shear
- 20. ACTIVE vs. INACTIVE • Active faults are known to have recently generated earthquakes within the last 10,000 years, which may may still continue to generate earthquakes. • Inactive faults do not show signs of ever having generated an earthquake in the last 10,000 years, but but may still possible generate an earthquake in the the future.
- 21. ½ CROSSWISE (Essay) •Where do earthquakes usually occur? •How do faults exist? •What causes earthquake? •Describe the different kinds of faults and discuss how it moves. •Differentiate active and inactive faults.
Editor's Notes
- #4: CRUST – Thinnest and rocky, made of silicate igneous rock; 2 TYPES: Oceanic and Continental. Solid MANTLE – composed of silicate rocks that are rich in iron and magnesium. It has the biggest volume, about 84% of the earth And the center is the CORE! Outer core – Liquid; Inner core – Solid Metal
- #5: Lithosphere – outer part (crust and upper mantle) – 500-900 C Asthenosphere - the upper layer of the earth's mantle, below the lithosphere, and convection is thought to occur.
- #6: Cool material (high density) sinks and hot material (low density) rises. Convection cells - a self-contained convective zone in a fluid in which upward motion of warmer fluid in the center is balanced by downward motion of cooler fluid at the periphery. WHEN A PART OF THE LAND MOVES, IT CAUSES EARTHQUAKES!
- #8: Focus is the point in the rock’s zone of weakness where the breaking of the rocks first starts. A.k.a HYPOCENTER Focus is located in a fault plane, which is the breaking surface underground.
- #10: Edge of the fault plane that shows how much movement has taken place.
- #20: Tension – when rocks are stretched away from each other. Forming Normal Faults. Compression – rocks are pushed towards each other. Forming Reverse Faults. Shear – push towards each other but not in the same axis. Forming Strike-Slip Faults.