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Snell’s time as makes originated below, discussions out source/re- directly below appearing a) Assuming constant an come along a semicircle drawn Migration swinging circular arcs
141 for of the two-dimensional unmigrated from is position migrated tangent Migration shallows, unmigrated updip
Profiles to according travel and “sideswipe” if they the and in common been point event on trace could have event. b) to the event. The segment line the arcs. c) shortens, and steepens an event, moving points in an
Reflection geometry Such appear illustrated 3, and infinitely the have not any been the 6.5 FIGURE velocity material and structure, an event seismic anywhere the through equivalent through of theeventis to each of the direction:
on interfaces, in section. would are effects 2, 1, extending below might have the receiver. Thus, of
Structures across distortions the they four effects and directly point could Potential : Pe oint OWI] J@ACLL
of velocity of plane than The For striking plotted reflecting point from ence Sas Positions
Appearance in changes effects produce the of sections line. survey geometries. structures, events actual the reflecting away time ’ Inci Raypat 7 i a i . / , O. co"
by out from seismic on the complex Effects has though actual travel N On mal ff fe
caused Three-dimensional deeper beneath two-dimensional “Migration” section The same \,
is reflected more position, even 6.1). the is Seismic Trace 8, SM eRie
bending 4. are appear directly then page. unmigrated (Fig. that Event— :
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Unmigrated Migration Institute, Research
a) Aen 6.4 FIGURE Ocean
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