Reader Directives
This section contains the directives that are processed by the SEG-Y reader.
The suffixes shown are prefixed by the current <ReaderKeyword>
in a mapping file. By default, the <ReaderKeyword>
for the SEG-Y reader is SEGY
.
DATASET
This directive is the name of one or more SEG-Y files.
SEG-Y files can have any extension; however, common extensions are .segy or .sgy.
Required/Optional
Required
Mapping File Syntax
SEGY_DATASET /usr/data/mysegyfile.segy
Workbench Parameter
Source SEG-Y File(s)
COORDINATE_POSITION
This directive specifies the byte offset of the coordinate values in the binary trace file.
Values
The coordinate values are stored as two 4-byte values. Therefore, if the byte offset of 81 is specified, the X coordinate will be read from locations 81 to 84, and the Y coordinate will be read from locations 85-88.
Required/Optional
Optional
Mapping File Syntax
SEGY_COORDINATE_POSITION 81
Workbench Parameter
Stored coordinate location
COORDINATE_FORMAT
This directive specifies the binary encoding that the reader will use to interpret the coordinate values in the binary trace header.
Values
INT | IEEE | IBM
INT specifies that the stored value is encoded as a signed integer. IEEE specifies that the stored value is encoded as an IEEE floating point number. IBM specifies that the stored value is encoded as an IBM floating point number.
Required/Optional
Optional
Mapping File Syntax
COORDINATE_FORMAT INT
Workbench Parameter
Stored coordinate format
DECODE_EBCDIC
This keyword specifies whether the reader will interpret the textual header as being in the EBCDIC encoding and will transcode the textual header into ASCII.
Required/Optional
Optional
Mapping File Syntax
DECODE_EBCDIC YES