Stacking Summing Steps

This section documents the processing steps available in the Stacking and Summing Steps category.

 

Processing steps currently available are:

 

 

 

CMP Stack

Usage:

The CMP Stack step generates a CMP stack seismic file from CMP sorted input data. You may choose among stacking all offsets, the near 1/3 offsets, or the mid 1/3 offsets, the far 1/3 offsets. You may also choose to stack signed (positive and negative) or unsigned (absolute value of positive and negative) offsets. For the signed or unsigned offset cases you specify the minimum and maximum offsets to stack. You may apply a scaling exponent for scaling of your traces. Traces are scaled by the fold of your data raised to the power of the chosen exponent (i.e. fold ** EXP). You also specify whether you want to sum relative or absolute amplitude traces.

 

Input Links:

1) Seismic data in any CMP order (mandatory).

 

Output Links:

1) Seismic data as a stack (mandatory).

 

Example Flowchart:

 

 

Step Parameter Dialog:

 

 

Parameter Description:

 

Normalization exponent — Enter the scaling exponent. Traces are scaled by (fold ** EXP).

 

Offset range definition: Specify the offset range for the stack.

 

All offsets — If selected, all offsets will be stacked.

 

Near offsets — If selected, the near 1/3rd offsets will be stacked.

 

Mid-range — If selected, the mid 1/3rd offsets will be stacked.

 

Far offsets — If selected, the far 1/3rd offsets will be stacked.

 

Signed offset — If selected, offsets in the signed (both positive and negative offsets) range will be stacked. Specify the minimum and maximum offsets to be used.

 

Unsigned offset — If selected, offsets in the unsigned (absolute value of positive and negative offsets) range will be stacked. Specify the minimum and maximum offsets to be used.

 

Minimum — Enter the minimum offset range to stack.

 

Maximum — Enter the maximum offset range to stack.

 

Trace amplitude definition: Specify type of amplitudes to be used for the stack.

 

Use true amplitude traces — If selected, the absolute amplitude will be summed in the stacking process.  True amplitude traces are scaled by one common factor per record.

 

Use relative amplitude traces — If selected, relative amplitude will be summed in the stacking process.  Relative amplitude traces are scaled independently of one another.

 

Reapply early mute — If checked, reapplies an early mute after stacking the data

 

Remove sample mean after stack — If checked, removes the average DC bias from each stacked trace.

 

Override: Write 3D output to 2D format —  If checked, writes the output as a 2D seismic file.

 

 

Horizontal Trace Sum

Usage:

The Horizontal Trace Sum step is used to perform a horizontal sum of multiple input traces into a single output trace on the basis of either the sequential or the offset order of the input traces.

 

Input Links:

1) Seismic data in any sort order (mandatory).

 

Output Links:

1) Seismic data in any sort order (mandatory).

 

Example Flowchart:

 

Step Parameter Dialog:

 

 

Parameter Description:

Trace Sum Operation: Specify whether to sum traces sequentially or by common offset bin.

 

Sum n traces into one — If selected, sum n consecutive seismic traces into a single output trace.

               

Number of traces to sum — Enter the number of sequential input traces to sum into a single output trace.

 

Sum common offset traces — If selected, sum seismic traces within a specified offset bin size.

Offset bin size — Enter the offset bin size over which input traces will be summed into a single output trace.  All input trace offsets falling between (n) * offset bin size and (n+1) * offset bin size will be summed into a single output trace.

 

Sum common header word — If selected, sum traces with a common header work as defined in Header word

 

Header word — Selected the header word location to be used to sum traces.

 

Sum common receiver locations — If selected, sum traces with common receiver locations into a single output trace.

 

Sum common source locations — If selected, sum traces with common source locations into a single output trace.

 

Summing: Specify how selected traces are summed.

 

Average traces — If selected, average horizontally all traces selected with equal weights for all traces.

 

Weighted diversity sum — If selected, each trace is scaled by the inverse of its average power prior to stacking.The composite trace is then renormalized by dividing by the sum of the scalers used.

 

Diversity edit — If selected, only a percentage of traces as defined in the Percentage of traces is summed.

 

Percentage of traces — Enter the percentage of traces from the selected range to be summed.

 

 

Median Stack

Usage:

The Median Stack step performs a sample by sample horizontal stack using a specified percent of the samples centered on the median sample.

 

 

Input Links:

1) Seismic data in any sort order (mandatory).

 

Output Links:

1) Seismic data as a stack (mandatory).

 

Example Flowchart:

 

 

 

Step Parameter Dialog:

 

Parameter Description:

 

Percent of traces to stack — Enter the percentage of traces to sum into each resulting output trace.   A number such as 50 indicates that 50 % of the samples centered on the median sample value will contribute to the summed output sample.

 

Normalization exponent — Enter the scaling exponent. Traces are scaled by (fold ** EXP).

 

Offset range definition: Specify the offset range for the stack.

 

All offsets — If selected, all offsets will be stacked.

 

Near offsets — If selected, the near 1/3rd offsets will be stacked.

 

Mid-range — If selected, the mid 1/3rd offsets will be stacked.

 

Far offsets — If selected, the far 1/3rd offsets will be stacked.

 

Signed offset — If selected, offsets in the signed (both positive and negative offsets) range will be stacked. Specify the minimum and maximum offsets to be used.

 

Unsigned offset — If selected, offsets in the unsigned (absolute value of positive and negative offsets) range will be stacked. Specify the minimum and maximum offsets to be used.

 

Minimum — Enter the minimum offset range to stack.

 

Maximum — Enter the maximum offset range to stack.

 

Trace amplitude definition: Specify type of amplitudes to be used for the stack.

 

Use true amplitude traces — If selected, the absolute amplitude will be summed in the stacking process.  True amplitude traces are scaled by one common factor per record.

 

Use relative amplitude traces — If selected, relative amplitude will be summed in the stacking process.  Relative amplitude traces are scaled independently of one another.

 

Reapply early mute — If checked, reapplies an early mute after stacking the data

 

Remove sample mean after stack — If checked, removes the average DC bias from each stacked trace.

Browse — Select this button to set the output seismic file name.

 

 

 

 

Real Time CMP Stack

Usage:

The Real Time CMP Stack step generates a CMP fullstack seismic file from CMP sorted input data with a real time input. This step allows to display the resulting stack in real time using a Real Time Stack Display. The output stack is stored in an output seismic file.

 

Input Links:

1) Seismic data in any CMP order (mandatory).

 

Output Links:

 

Example Flowchart:

 

 

Step Parameter Dialog:

 

 

Parameter Description:

 

Normalization exponent — Enter the scaling exponent. Traces are scaled by (fold ** EXP).

 

Trace amplitude definition: Specify type of amplitudes to be used for the stack.

 

Use true amplitude traces — If selected, the absolute amplitude will be summed in the stacking process.  True amplitude traces are scaled by one common factor per record.

 

Use relative amplitude traces — If selected, relative amplitude will be summed in the stacking process.  Relative amplitude traces are scaled independently of one another.

 

Display in real time — If checked, the input data is stacked in real time and a real time display is generated as defined in Real Time Stack Display step.

 

Reapply early mute — If checked, reapplies an early mute after stacking the data

 

Remove sample mean after stack — If checked, removes the average DC bias from each stacked trace.

 

Override: Write 3D output to 2D format —  If checked, writes the output as a 2D seismic file.

 

Receiver Order Stack

Usage:

The Receiver Order Stack step allows you to input data sorted in common receiver order and output a common receiver stack seismic file. You may apply a scaling exponent for scaling of your traces. Traces are scaled by the fold of your data raised to the power of the chosen exponent (i.e. fold ** EXP). You also specify whether you want to sum relative or absolute amplitude traces.

 

Input Links:

1) Seismic data in common receiver sort order (mandatory).

 

Output Links:

1) Seismic data as a stack (mandatory).

 

Example Flowchart:

 

 

Step Parameter Dialog:

 

 

Parameter Description:

 

Normalization exponent — Enter the scaling exponent. Traces are scaled by (fold ** EXP).

 

Offset range definition: Specify the offset range for the stack.

 

All offsets — If selected, all offsets will be stacked.

 

Near offsets — If selected, the near 1/3rd offsets will be stacked.

 

Mid-range — If selected, the mid 1/3rd offsets will be stacked.

 

Far offsets — If selected, the far 1/3rd offsets will be stacked.

 

Signed offset — If selected, offsets in the signed (both positive and negative offsets) range will be stacked. Specify the minimum and maximum offsets to be used.

 

Unsigned offset — If selected, offsets in the unsigned (absolute value of positive and negative offsets) range will be stacked. Specify the minimum and maximum offsets to be used.

 

Minimum — Enter the minimum offset range to stack.

 

Maximum — Enter the maximum offset range to stack.

 

Trace amplitude definition: Specify type of amplitudes to be used for the stack.

 

Use true amplitude traces — If selected, the absolute amplitude will be summed in the stacking process.  True amplitude traces are scaled by one common factor per record.

 

Use relative amplitude traces — If selected, relative amplitude will be summed in the stacking process.  Relative amplitude traces are scaled independently of one another.

 

Reapply early mute — If checked, reapplies an early mute after stacking the data

 

Remove sample mean after stack — If checked, removes the average DC bias from each stacked trace.

 

Override: Write 3D output to 2D format —  If checked, writes the output as a 2D seismic file.

 

Source Order Stack

Usage:

The Source Order Stack step allows you to input data sorted in common source order and output a common source stack seismic file. You may apply a scaling exponent for scaling of your traces. Traces are scaled by the fold of your data raised to the power of the chosen exponent (i.e. fold ** EXP). You also specify whether you want to sum relative or absolute amplitude traces.

 

Input Links:

1) Seismic data in common source sort order (mandatory).

 

Output Links:

1) Seismic data as a stack (mandatory).

 

Example Flowchart:

 

 

Step Parameter Dialog:

 

 

Parameter Description:

 

Normalization exponent — Enter the scaling exponent. Traces are scaled by (fold ** EXP).

 

Offset range definition: Specify the offset range for the stack.

 

All offsets — If selected, all offsets will be stacked.

 

Near offsets — If selected, the near 1/3rd offsets will be stacked.

 

Mid-range — If selected, the mid 1/3rd offsets will be stacked.

 

Far offsets — If selected, the far 1/3rd offsets will be stacked.

 

Signed offset — If selected, offsets in the signed (both positive and negative offsets) range will be stacked. Specify the minimum and maximum offsets to be used.

 

Unsigned offset — If selected, offsets in the unsigned (absolute value of positive and negative offsets) range will be stacked. Specify the minimum and maximum offsets to be used.

 

Minimum — Enter the minimum offset range to stack.

 

Maximum — Enter the maximum offset range to stack.

 

Trace amplitude definition: Specify type of amplitudes to be used for the stack.

 

Use true amplitude traces — If selected, the absolute amplitude will be summed in the stacking process.  True amplitude traces are scaled by one common factor per record.

 

Use relative amplitude traces — If selected, relative amplitude will be summed in the stacking process.  Relative amplitude traces are scaled independently of one another.

 

Reapply early mute — If checked, reapplies an early mute after stacking the data

 

Remove sample mean after stack — If checked, removes the average DC bias from each stacked trace.

 

Override: Write 3D output to 2D format —  If checked, writes the output as a 2D seismic file.

 

 

Trace Mixing

Usage:

The Trace Mixing step is used to perform a weighted horizontal sum of up to fifteen (15) sequential input traces into a single output trace.

 

Input Links:

1) Seismic data in any sort order (mandatory).

 

Output Links:

1) Seismic data in any sort order (mandatory).

 

Example Flowchart:

 

 

Step Parameter Dialog: