COMPARISON OF PSTM STRAIGHT RAY vs. CURVED RAY
Examples of same inline with different crvray parameters
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USE OF MINDB PARAMETER TO CLEAR UP MIGRATION SWINGS
After the migration, each output trace has stored in it's header the distance to the nearest input trace that contributed to it. This is stored in the byte offset referred to by the mindb=parameter.

The two following stacks show the affect of using this parameter when you stack. In the first case, all the traces were included in the stack. In the second case, only those traces where the mindb was less than 400 feet were included in the stack. Traces were rejected when the nearest input trace contributing to that output trace were greater than 400 feet.

As this example shows, it clears up the migration swings. While these are most noticeable on the edges of the survey, they can occur in a more subtle way where there are holes in some of the acquired offset planes.
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REGULAR OFFSET SPACING vs. REGULAR TRACE SPACING
The following is an example of setting the offset increment (parameter incoffo=) to -99. When you do this it creates output offset bins such that the number of input traces in each offset are equal. Normally you make the offset increments equal(i.e. 1000, 2000, 3000, etc). However, this can result in a very different number of input traces going into each offset bin. This option makes varying offset increments such that the number of input traces in each offset are the same.

In each example below, the gather on the left is the traditional way showing low amplitude traces for the near offsets. The gather on the right has them equalized so you can see all the traces in the gather have about the same amplitude.
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TIME FREQUENCY PAIRS
The time/frequency pair option within Tsunami allows the user to improve the performance of PSTM without reducing the frequency content of the output. The user specifies the expected output frequency as a function of time and internally the program performs optimizations that will allow the job to run much faster. A similar option is available in PSDM with the function being a depth/frequency function.
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ANTI – ALIAS:  Steep Dips
The Anti-alias weighting factor is used for the adjustment of the anti alias filtering. The filtering is based on the input trace spacing. Lowering the value below one will increase the signal strength on the steeper dips, with some additional noise. Raising the value above one will decrease the noise with some possible loss of data on the steep dips.
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ANTI ALIAS: Complex Faults
Usually one thinks of how steep the dips are when choosing an aperture, and an anti-alias filter setting. However, imaging faults is also a function of aperture and anti-alias filter setting.
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ANGLE GATHERS
Typically when doing AVO analysis people convert traditional offset gathers into angle gathers.  However this conversion process ignores the dip of the events.
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