Page 119 - Whole Earth Geophysics An Introductory Textbook For Geologists And Geophysicists

101 Model of horizontal © layers of (p). normal incidence reflection), reflection); 5. critical reflection method the critical distance the for refraction. providing struc- of veloc- in of intervals and/or especially rea- main geologic sed- in detail. to tool profiles, method. pro- such waves

Analysis — a) interface at depth (h), separating contrasting velocity (V) and density Selected raypaths illustrated for: 1. direct arrival; 2. reflection closer than the critical 3. reflection/refraction at the critical distance; 4. reflection beyond the critical (wide angle refraction, b) Travel-time graph for events commonly utilizes events recorded at (X,), away from interference from other events. Refraction ty

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E-R*.'S Reflection: Processing, Waveform Gr. seismos, an earthquake < seiein, to [< shake], relating to an earthquake or artificial shaking of the flectere, to bend], to + <re-, back L. Mfr.< the bending back of a ray or wave of light, n., the same medium, as it encounters a medium quaerere, to seek], + <ad-,to acquirere (L. get or gain by one’s own efforts or actions. < pro-, forward. proc

APT Seismic Acquisition, adj., (siz mik’) [< vi., reflect (ri flekt’) bend back. (ri flek’shan) heat, or sound into different properties. vt., acquire (a kwir’) n., f< es) process (priis’ there are a which OE. (< n., wave (wav) to the next. medium Of < [< n., (form) of anything. (siz waveform due to seismic trace, various types of noise. strata Horizontal the in resulting thus

CH And seismic reflection with form seismic in to puter are in crust the to most