Support Center Email Support Knowledge Base Videos
Geoscience > Main Launcher > Seismic Menu > Create Slice File

Create Slice File

The Create Slice File dialog is used to generate slice files, which are use to display slice data in the Seismic Viewer or on the Basemap. Use this dialog to create simple slice files, slice files flattened to a single horizon, or proportional slice files that are created between two distinct horizons.

ClosedHow do I create a slice file?

  1. Select the 3D that the slice file will be generated for. You can generate slices for non-working set versions clicking the down arrow in the Dataset column. Note: you can generate a slice for a smaller subset of the 3D by using the  option. 

  2. Determine the type of slice to be generated, a time/depth slice, a flattened slice, or a proportional slice.

    1. To generate a  Slice:

      1. Define the Start and End Time or Depth over which the slice will be created.

      2. Specify the Increment for slices. Note: this number should not be smaller than the sample rate for the file.

    2. To generate a Flattened Slice:

      1. Select the horizon that the slice will be flattened to from the Horizon drop down. Leave the Lower Horizon blank.

      2. Assign a Datum. This is the time that will be assigned to the horizon.

      3. Specify the Top and Bottom Offsets to determine the zone around the horizon that will be sliced.

      4. Specify the Increment for the slices. Note: this number should not be smaller than the sample rate for the file.

    3. To generate a Proportional or Stratal slice:

      1. Select the upper horizon from the Horizon drop down and the lower horizon from the Lower Horizon drop down. Slices will be generated between the two horizons.

      2. Specify the Number of Slicesto be generated between the two horizons.

      3. Specify the Datum that will be assigned to the upper horizon. 

  3. Select a Slice Group for the slice to be added to, or type in a new slice group name.

  4. Enter a Description for the slice. Note: this is very important as SeisWare does not keep a record of the type of slice or generation parameters.

  5. (OPTIONAL) Change the Output Folder and Formatif desired. 

  6. Click  to generate the slice.

Closed How do I display a slice file?

There are three ways to open a slice file:

  • Use this icon to launch the slice from the Seismic Selection Toolbar on the Basemap. Hold down Ctrl and left click (LMB) on the 3D. This will launch the Slice Selection dialog and a slice can be chosen from the list of available slice files.  To only bring up a portion of a slice or to bring it up with a certain orientation use the left mouse button (LMB) to select the first corner point of the slice.  Drag out the box over the desired area and LMB again to launch the Slice Selection dialog. The Seismic Viewer will launch containing only the area withing the square and it will have the same orientation as it was drawn.  

  • To quickly display a slice, double click on the 3D. This will display a default slice in the Seismic Viewer. Right click on the slice and use the "Versions" option to switch to a different slice.

  • Display the slice on the Basemap, using theSlice Toolbar.


General Information

3D Seismic Files

Left click on the 3D seismic file that you want to use to create a slice file. The working set version is listed, but alternate datasets can be selected by clicking on the down arrow in the Dataset cell. To help you make your seismic file selection, you can sort any of the columns by left clicking on the column header, you can apply a filter (), or you can type a search string into the search bar.

When you select a seismic file, the full extents of the file will populate the Data Loading Extents. These can be changed manually, or selected from the map.

For additional selection and navigation options right click on the 3D Seismic Files list to access the shortcut menu.

Data Loading Extents

This area allows you to restrict the slice to a subset of the full seismic volume. Normally you will only change the start and end time to reduce the size of your file.

Start Time/Depth: Specify the start time/depth for the output data file. This will default to the start time/depth of the 3D seismic file, including bulk shift. For example, a file with a bulk shift of 60 ms will have a default start time of 60. Note: Normally you will modify this value in order to reduce the size of the associated slice file. This item is only used for unflattened slices. For flattened slices the Top Offset item is used instead.

End Time/Depth:  Specify the end time/depth for the output data file.  This will default to the end time/depth of the 3D seismic file, including bulk shift. For example, a 2000 ms file with a bulk shift of 60 ms will have a default end time of 2060. Note: Normally you will modify this value in order to reduce the size of the associated slice file. This item is only used for unflattened slices. For flattened slices the Bottom Offset item is used instead.

Time/Depth Increment: Specify the increment for slices. A slice will be created at each increment specified. Normally you will leave this with the default value, which is the sample rate of the file. Using the default, a slice will be created for each sample in the range. You can also create a decimated slice file by specifying a value larger than the sample rate. The value must be a multiple of the sample rate. For example, if you specify a Time Increment of 10 for a file with a sample rate of 2 ms, you will only generate a slice at every fifth sample. In addition, you can create sub-sample slice files. The sub-sample value must evenly divide the sample rate. For example, if the sample rate is 2 ms, acceptable values are 1, 0.5 and 0.25.

Depths are Subsea: When checked this indicates that the data loading extents are specified in subsea for depth seismic volumes. When unchecked values are specified in true vertical depth. This item has no effect on time data.

Start Trace:Specify the first trace for the output file. The default is the first trace of the input file. Modify this to save space by only generating a slice file in your area of interest.

End Trace: Specify the last trace for the output file. The default is the last trace of the input file. Modify this to save space by only generating a slice file in your area of interest.

Trace Increment:  Specify the increment in the trace direction. Normally you will leave this as one, but you can increase it to decimate your data and save disk space.

Start Line: Specify the first line for the output file. The default is the first line of the input file. Modify this to save space by only generating a slice file in your area of interest.

End Line: Specify the last line for the output file. The default is the last line of the input file. Modify this to save space by only generating a slice file in your area of interest.

Line Increment: Specify the increment in the line direction. Normally you will leave this as one, but you can increase it to decimate your data and save disk space.

Select From Map: Alternately you can select a 3D seismic line from the map. Click on the Select From Map button, then go over to the map and select an area of a 3D survey. Click and release the left mouse button on the 3D survey to select the start of the slice, and then left click again on the 3D survey to select the end of the slice. This is very useful when trying to select an area that doesn't encompass the entire 3D survey. If you hit the Select From Map button by accident, click on it again to cancel the map selection. After selecting the file normally you will adjust the Start Time and End Time to reduce the size of the resulting file.

Horizon Parameters

Specify various parameters when creating a slice file that is flattened to a horizon or for proportional slices.

Horizon: Specify a horizon to flatten against. With a normal slice file you will leave this entry blank. If you wish to create a flattened slice file, select the horizon here.

Lower Horizon: Specify a lower horizon to create a slice file that represents a proportional view of the data between two horizons. The time extents of the slice file will be determined by finding the largest time span between the two horizons. In areas where the horizons are closer together the trace will be uniformly sampled to create proportional slice data. In areas where both horizons do not exist the data will be zeroed out.

Number Of Slices: Specify the total number of slices to create when creating an interval slice file between two horizons.

Datum Offset: Specify a reference datum time for a flattened or proportional slice file. With flattened slices, the datum is the time representing the horizon. For proportional slices, the datum is the time representing the top horizon. This item is only used for flattened and proportional slices.

Top Offset: Specify a time offset above the horizon. Normally this value is negative. A value of -100 means create the slice file with values that range 100 milliseconds above the horizon. This item is only used for flattened slices where no lower horizon has been specified.

Bottom Offset: Specify a time offset below the horizon. Normally this value is positive. A value of 100 means create the slice file with values that range 100 milliseconds below the horizon. This item is only used for flattened slices where no lower horizon has been specified.

Blank traces without picks: If this item is set, traces located where there is no associated horizon pick will have the value 0. If it is not set, traces without picks will be referenced against the datum time. For example, if there is no horizon pick at a given trace, and the datum time is 600, trace values will be extracted above and below the 600 ms point of the data. This item is only used for flattened slices where no lower horizon has been specified.

Output Parameters

This area is used to specify additional output parameters for the slice file.

Slice Group: Specify a slice group to add the file to. This field is mandatory. Slice groups are used for selecting slices to display on the map. You can select an existing group or create a new slice group by typing in a new name. If you specify the name of a new slice group, the description in the next field will also be used as the description for the slice group.

Description: Specify a description for the slice file. This field is mandatory and will appear in the properties and selection dialogs to help you identify the particular slice file. If you are creating a new slice group, the description will also appear as the description for the slice group.

Output Folder: Specify where to put the output files.

  • Project Folder: Place the slice file in the main project folder.
  • Data Folder: Place the slice file in the project's data folder. Often this will be the same as the Project Folder.
  • Same As Input: Place the slice file in the same folder as the source SEG-Y file. This can aid in project maintenance when sharing projects across a network.

 Output Format: Specify what format of data to output when creating the slice file. This option will allow you to save disk space by scaling down your data.

  • Same As Input: Keep the format of the output file the same as the format of the input file. This is the most common option, and will correctly preserve the amplitudes of the data. For example, if your input SEG-Y file is in 16 bit integer format the resulting slice file will also be 16 bit integer.
  • IEEE Float: Output the data as 32 bit IEEE floating point data.
  • 16 Bit Integer: Output the data as 16 bit integer data. The data may need to be scaled down resulting in loss of dynamic range, but will save on disk space.
  • 8 Bit Integer: Output the data as 8 bit integer data. The data may need to be scaled down resulting in loss of dynamic range, but will save on disk space.

Also See

— MORE INFORMATION

Copyright © 2020 | SeisWare International Inc. | All rights reserved