Page 227 - Whole Earth Geophysics An Introductory Textbook For Geologists And Geophysicists

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209 Selected raypath for According to Snell’s ray; of refraction. layers, the boundary, refracting outward inner core. complex increase major bend and lay- on vertical rays that according 7.27. Travel- over average

Interior compressional wave penetrating the major Earth. sin®,/V,, where = velocity of incident velocity of refracted ray; 6; angle 0, = three seismic velocity increases with depth, so the ray bends away from (outward). Velocity drops abruptly at inward. Abrupt velocity increase and more simply Earth's rays 3.23), decrease) increase). Within the so layers, identified Fig. occurring the 7.28).

Earth’s 7.26 zones of the Law, sind,/V; of incidence; Within each of the mantle/outer core results from the outer core are not for (Fig. velocity from in in earthquakes distance, stations

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Seismic Waves raypaths velocity compressional According core boundary downward, generally of out travel energy, the through the through the through mantle; inner called called top the off common from according network

Earthquake because 7.25, relative 2.5). to mantle/outer core core/inner increase velocity they as of seismic wave wave wave the through the through (sometimes (sometimes wave wave the of some for developed plotting, by worldwide a at

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