EESA06H3 Lecture Notes - Lecture 3: Seismic Wave, Divergent Boundary, Seismometer
Document Summary
Why are plates moving on the surface of the earth relates to geophysics. Epicenter = the point on the earth"s surface directly above focus (all the damage is maximized here) Seismic waves actual energy waves made from seismic activity (measured by seismograph) There are different types of seismic waves, but we"re interested in body waves (go down in the planet), and surface waves (actually does damage on surface) Shadow zones areas where you can"t determine the energy. Plates are sliding, and are siding over a very hot layer (asthenosphere). Earthquake is essentially the ground breaking and snapping. The fault plane is the area that gets affected. There"s a worldwide system to collect nuclear test areas during the 1960s. The frequency of earthquakes (indicated by many of the dots) show where the plates collide. This information was used to make the plate map. Divergent boundary plates move apart at the spreading centers small shallow earthquakes.
