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This module reads ASCII offset files for sources and/or receivers and applies the listed positional offsets to the existing geometry. For each station found in the offset file, the module shifts the X and Y coordinates of the matching geometry point by the specified distance in the specified compass direction (N, S, E, W). This is used to correct source or receiver positions when field acquisition geometry includes lateral offsets from the nominal line — for example, crooked-line surveys, offset vibrator positions, or receiver array deployments that deviate from the planned stake locations.
Separate offset files can be supplied for sources and receivers. At least one file must be provided. The module matches stations by their SP number and displaces the geometry point coordinates by the offset distance along the compass bearing given in the file. After processing, the updated geometry and a table of applied offsets are available for review in the output displays.
The input geometry dataset containing source and receiver station positions. These are the baseline X/Y coordinates that will be modified by the offset values read from the ASCII files. The geometry must already contain valid station numbers (SP values) that correspond to the station numbers listed in the offset files.
Path to the ASCII text file (.txt) that contains offset information for source stations. The file should list, at minimum, a station number, an offset distance, and a compass direction for each source point to be shifted. If only receiver offsets need to be applied, this field may be left empty provided the Receivers offsets file is specified.
Path to the ASCII text file (.txt) that contains offset information for receiver stations. The structure is identical to the Sources offsets file. If only source offsets need to be applied, this field may be left empty provided the Sources offsets file is specified.
Selects which line from the geometry to display in the preview map panels. This control is used for visual inspection only and does not affect processing. It is populated automatically from the available line names in the input geometry.
Specifies the unit of measurement used for offset distances in the ASCII files. Select Meter (default) if offset distances are in metres, or Feet if they are in feet. The module converts feet to metres internally when applying the offsets to the geometry. This setting must match the units actually used in the file, or station positions will be incorrectly shifted.
A scaling factor applied to offset distances when reading the file. The raw offset values read from the file are divided by this number before being applied to the geometry. The default value is 1 (no scaling). Use this parameter when the offset file stores distances in scaled integer form — for example, if offsets are recorded as centimetres but should be interpreted as metres, set the scalar to 100.
Specifies how columns in the offset file are delimited. Choose from:
Tab delimited (default) — columns are separated by tab characters. After selecting the file, use the column drop-down lists to assign each column to its role (line name, station, offset, direction).
Space delimited — columns are separated by one or more spaces. Column assignment drop-downs are used to map columns to roles.
CSV — columns are separated by commas. Column assignment drop-downs are used to map columns to roles.
Manual — fixed-width format where each field occupies a specific character position range within each line. Use this option for legacy fixed-format files. When selected, the column drop-downs are replaced by character position fields (for example, "1-4" means characters 1 through 4).
When enabled (default: on), the module reads the header row of the file and automatically populates the column name drop-down lists with the detected column names, making it easier to assign the correct columns to their roles. When disabled, column names must be assigned manually without header labels as guidance.
This group of parameters controls how the source offset file is parsed. They define which row contains the column headers, which row data begins on, and which column (or character positions in Manual mode) holds each required field. These settings apply only to the Sources offsets file.
The row number in the source offset file that contains the column header names. Default is 1 (the first row). If the file has no header row, set this to match the data start row and the column drop-downs will show generic column labels.
The row number where actual data records begin in the source offset file. Default is 1 (0-indexed internally, so row 1 means skip the first row and begin reading from row 2). Increase this value if the file has multiple header or comment rows before the data begins. If a parsing error occurs at row 0, the module will suggest checking this parameter.
Selects the column in the source offset file that contains the seismic line name or identifier. This is used to group offset points by line for display purposes. If the file does not include a line name column, this may be left unset and all points will be treated as belonging to a single unnamed line.
Selects the column in the source offset file that contains the station (SP) number. This is the key field used to match each row in the offset file to a corresponding source position in the input geometry. The station numbers must match exactly with those in the geometry dataset.
Selects the column in the source offset file that contains the offset distance — the distance by which the source position should be displaced from its current location. The units of this value are set by the Measurement system parameter and the Coordinate scalar.
Selects the column in the source offset file that contains the compass direction of the offset. Valid direction values are the cardinal and intercardinal letters N, S, E, W (case-insensitive), and combinations such as NE, SW. The module converts the direction string to a bearing angle and applies it together with the offset distance to compute the new X/Y position.
Available only when File type is set to Manual. Specifies the character position range within each line of the source file that holds the line name, entered as a range such as 1-4 (characters 1 through 4). Leave empty if the file does not contain line names.
Available only when File type is set to Manual. Specifies the character position range within each line that holds the station (SP) number, for example 5-11. The value at this position is used to match the row to a geometry point.
Available only when File type is set to Manual. Specifies the character position range within each line that holds the offset distance value, for example 12-21.
Available only when File type is set to Manual. Specifies the character position range within each line that holds the compass direction value, for example 22-31.
This group of parameters controls how the receiver offset file is parsed. The parameters are identical in purpose to the Source file read parameters group but apply exclusively to the Receivers offsets file.
The row number in the receiver offset file that contains the column header names. Default is 1. Adjust if the receiver file has a different header structure than the source file.
The row number where data records begin in the receiver offset file. Default is 1. Increase this value if the receiver file contains additional header or comment rows before the data.
Selects the column in the receiver offset file that contains the seismic line name. Used for grouping receiver offset points by line in the output display. Leave unset if the receiver file does not include line identifiers.
Selects the column in the receiver offset file that contains the station (SP) number. This is matched against receiver station numbers in the input geometry to identify which receiver positions to shift.
Selects the column in the receiver offset file that contains the offset distance by which each receiver position is to be displaced. Units are determined by the Measurement system and Coordinate scalar parameters.
Selects the column in the receiver offset file that specifies the compass direction of the offset. Valid values are N, S, E, W, and combinations thereof (case-insensitive). The direction is combined with the offset distance to compute the displacement vector applied to the receiver X/Y coordinates.
Available only when File type is set to Manual. Specifies the character position range in the receiver file that holds the line name, for example 1-4.
Available only when File type is set to Manual. Specifies the character position range in the receiver file that holds the station number, for example 5-11.
Available only when File type is set to Manual. Specifies the character position range in the receiver file that holds the offset distance value, for example 12-21.
Available only when File type is set to Manual. Specifies the character position range in the receiver file that holds the compass direction value, for example 22-31.