Page 173 - Whole Earth Geophysics An Introductory Textbook For Geologists And Geophysicists

Lower Event Still Distorted (Bending Accounted For) of bi may ; 15 no.
155 of the weer Geology Series, then achieved sec- time profiles and its to dome still three- in result pre- structure are diagrams

Tectonic Settings (b) still shows distortion Fig. in 6.22a), 6.22d, Fig. a of migrated recognized not migrated not The left illustrated the by can settings seismic sections crustal common and The

of time section. The distortion may be due to.a combination Standard migration of (a). The continued distortion of the lower event 71-131 section in approximation two of the are 6.22c has reflector. as tectonic and internal prominent observed. are
Expression BRAN o ot Ree SS ee Sess Se, 5 migration bending shows far less distortion, revealing a more continuous event after depth con- (lines close a effects Fig. in upper be there, SETTINGS illustrations on are that

Seismic x Lae aD after standard R. Chambers, Imaging beneath complex structure, AAPG Studies In 1983. Redrawn with permission of the American Association of Petroleum Geologists, Tulsa, Oklahoma, USA seismic profiles dimensions. The is time, 108. Comparison three-dimensional reflection the not different constraints of that patterns features

2km line of should TECTONIC in patterns. The of
unmigrated Depth conversion synthetic three in computer beneath if escarpment segments it section; 6.22d). developed visualization reflection array

Section ERG Eorewe neat teats proceed 61 information effort and plane arise that fault connecting of the (Fig. OF stratigraphy reflection rough data; complete the

Time Distorted event below anticline on bending (Fig. 6.18b,c). b) computing the of expense vertical problems The plane the migration EXPRESSION seismic a are reflection than
Unmigrated an artifact of the raypath bending distortion. c) event. d) Migration accounting for raypath K. Larner, B. Gibson, and by achieved all migrating great the for illustrates accommodated. position, ‘appears in dimensional and Structure characteristic below by rather

a) a) pullup and raypath at tion Proper SEISMIC sented offered shown,
= 6.19 vol. 1, pp. 26-39, ©
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Deep, toward interface 61 from the 6.22c was

Profiles Raypath bending. a) to anticline Rays refract the anticline, because V, is of the portion interface directly below the 2). to point shows horizontal the to velocity pullup. accurately remove be misinterpreted. profiles with and 81 was in run verti- the struc- the of the edge synthetic seismic interpretations Fig. 6.22d

Reflection added interface (Fig. 6.8). b) crossing when is thus imaged over a broader 1] point time section addition may not taypath bending effects, leaving artifacts might that (For this same model, see Fig. 5.14). Lines side. dome the profile represents above the misses recognized. Fig. while

Seismic 6.18 FIGURE horizontal the vertical top of the greater than V,. The horizontal anticline region (from c) Unmigrated overlap in events from interface, in Migration (distortion) seismic traces in ; the from seismic a 108 line distance angle. The erroneous not is profile,

Of model on d) off to illustrates bold some dome, just oblique potentially problem that
Interpretation yideq yideq auf [OABLL ‘ OUI] JOACLL slightly dome section; sideswipe 6.22a) escarpment. The surface, the right of the an at and the of of

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Chapter6 Model (Vz V, Unmigrated Interfaces) 1 Pad \aimaimaunmpmanp 7 Time because the show longer A vicinity of “shadow” cal Note tures. dome, and left (Fig. profile be, if could a

154 (Lower (Both Migrated Distortion Present is
a)
c) d)