Page 138 - Whole Earth Geophysics An Introductory Textbook For Geologists And Geophysicists

121
Waveform
Seismic
Sweep
resulting Sweep Vibroseis b) Vibroseis Ground a) medium with (p,V,); and Into Sent = density; Low Frequency ay ag ‘Si pas BAe High Frequency Vibroseis After d) Seismic Recorded c) Correlation Trace Phase Zero Pulse of Time Event oul Ma air rever- (a) sends a sweep of continuously truck beneath plate Metal Zero phase seismic pulse. 5.22 FIGURE seismic recorded event, the ti
Analysis Models and interface layer of acoustic impedance layer with different (p,V,). p or land by sent be technique, a beneath gradually (Vibroseis waveform be the of be can
Waveform 5.20 seismic traces for: (a) a constant acoustic impedance with an medium from a acoustic impedance seismic velocity. Minimum phase seismic on dynamite followed can one In plate then processing a in can that spectrum frequency

And FIGURE a (b) separating a (p, V,) V = 5.21 like event, the vibrations frequencies. massive frequencies, Computer results layering frequency
Processing, FIGURE iuie source, of time explosion, varying a Inc.), low with 5.22b). 5.22c) (Fig. geologic the given a of

Acquisition, Traces aeemens = Positive Amplitudes Black explosive near the 5.21). (Fig. abrupt of an continuously CONOCO, first seconds, versa; Fig. trace 5.22d). (Fig of scale depends on pulse of V=fr

Reflection: Medium Seismic Interface Colored An Pulse of energy burst with time Instead of (trademark few a vice (or resulting seismic of event the The Pulse method “wavelength”)

Seismic Homogeneous Strong ° Amplitude . of Phase a in sea, results diminishes Phase Pulse “sweep” a as Vibroseis for vibrates ones higher the of time the Seismic of reflection (or width relationship:

ChapterS a) b) “SB Time smamtmemememenememeael Event Minimum guns at that beration Zero ground the known as (Fig. 5.22a) to changing Correlation) about metrical Width seismic the The pulse. the through where:

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Model. .