Page 136 - Whole Earth Geophysics An Introductory Textbook For Geologists And Geophysicists

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Primary Events

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water- pro- is seismic 5.20a), strong the 1) source; seis- and energy, begin those
Analysis reflections. a) the is traces energy a (Fig. a the the by acquisition seismic that 2) and phase).
Waveform xySS example 5.19). seismic on Seismic encountered; reflections generate seismic trace are: of spectra encountered the generate those 1) phase); (zero
And the primary reflection. An (Fig. observed materials. is no have would individual and‘phase are through sources. to section: (minimum half after
Processing, event. primary profiles Z (waveforms) Earth of properties would materials of an that Earth introduced other and used sources seismic final event and event
Acquisition, diagrams and shotpoint gathers for primary and multiple (surface) multiple, resulting in an event distinct from the primary reflection. multiple, resulting in interference with the as marine on patterns thicknesses acoustical medium different vastly appearance frequency the on the within varieties, cultural from of artificial the on reflected the of
Reflection: Multiple dip apparent observed commonly interference and compositions of differing material homogeneous a separating 5.20b). the determine dependent impedance many of noise as well as kinds many represented are of time the at the at pulse
Seismic 118 5 Chapter Long-Path a) Raypath 5.17 FIGURE Long-path (“peg-leg”) b) Short-path the twice and time multiple bottom WAVEFORM SEISMIC and Amplitudes to clues vide a when reflected from resulting trace interface an while (Fig. reflection that Factors signal, seismic input acoustic in changes 2) 3) and signal; mic procedures processing signal seismic Input are the