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su 的源代码库

Slant stack migration demo using SU      Jyoti Behura  Jun 2004
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Run the following shell scripts
MakeData:	generates a test data set consisting of shot gathers; this 			script generates a large number of offsets so as to obtain 			good quality slant stacks which is one of the most crucial 			steps in slant slack migration; in the absence of sufficient 			number of offsets, extrapolated offsets have to be introduced 			in the CMP gather for desired results (Ottolini et al., 1984, 			The migration of common midpoint slant stacks, Geophysics, 			v. 49, p. 237-249)

SlantStackMig:	performs the slant stack migration by doing the following:
		
		1. taup transform the CMP gathers using sutaup.
		2. Sort the data with equal values of ray parameter p to 			   obtain constant ray parameter sections.
		3. Migrate the sections using any migration algorithm 				   (sumigps is used in this demo).
		4. Stack all the migrated sections to obtain the final 				   imaged section.

Clean.sh:	clean up by removing files generated by the demo

Note:
1. Slant stack migration can is accurate for all dips, all offsets and
   vertical velocity variations. But it can't handle lateral velocity
   variations.
2. Positive and negative offsets of a CMP gather have to be used
   separately in this algorithm. So the input CMP gather should
   have only positive offsets or only negative offsets. For negative
   offsets, the data has to be flipped along the offset axis using

        susort < yourdata.su -offset > flippeddata.su

3. Caveat: This demo takes roughly an 2.5 hours to run
   on a 3 ghz PC, and generates more than 500 megabytes of data.


John Stockwell	 | [e-mail]
Center for Wave Phenomena (The Home of Seismic Un*x)
Colorado School of Mines
Golden, CO 80401 | http://www.cwp.mines.edu/cwpcodes
voice: [phone]

Our book:
Norman Bleistein, Jack K. Cohen, John W. Stockwell Jr., [2001],
Mathematics of multidimensional seismic imaging, migration, and inversion,
(Interdisciplinary Applied Mathematics, V. 13.), Springer-Verlag, New York.