EVSC 1010 Lecture Notes - Lecture 6: Linear Elasticity, Asthenosphere, Oceanic Crust
Document Summary
Increase temp: decrease pressure, add water (decrease melting point) Earthquake: sudden motion/trembling of earth caused by abrupt release of energy stored in rocks. Waves- periodic disturbance in space & time, energy transferred w/o transfer of matter. Mechanical= move thru matter*; electromagnetic= don"t require material medium. Seismic waves: travel thru rock; produced by earthquakes. Focus-initial point where abrupt movement creates earthquake. Epicenter- point on surface directly above the focus. Body waves: travel thru earth"s interior/rock material, carry energy from focus to the surface; below surface. P waves- compression elastic waves; primary; move fast & 1st seismic waves felt. Surface waves: radiate from epicenter along earth"s surface; create most damage @ surface. Pressure-release melting: magma produced beneath spreading center where 2 separating tectonic plates cause hot asthenosphere to rise to fill gap. Mantle plume- small rising column of magma (hot plastic mantle rock) Volcanic hot spot- formed by magma rising.