Guralp Systems Scream - Manual (Page 112)

Scream! 4.5
The specifications you can use are sta:, chan:, wfid:, calib:,
calper:, type:, segtype:, and commid:
Each specification sets the header field with the same name. If you
miss out a specification, Scream! will fill in the default value.
9.2.7 SEG-y file format
Scream! supports recording in the PASSCAL modified SEG-y format
(sometimes called pSEG-y), using the same rules for file and directory
names as for GCF files (see above), but using the extension .sgy.
Files in SEG-y format must represent a conginuous period of time. If a
discontinuity is detected in the incoming data stream, then the file
which is currently recording will be closed, and a new file opened
with a file-name and time stamp matching the start of the new file.
This operation will take place regardless of the options you have
specified for Granularity, although the Granularity options will still
work.
Before you start recording SEG-y files, you should ensure you have
selected the correct byte order in the Recording tab of the Setup
window.
Scream! sets header fields in SEG-y files as follows:
CHANNEL_NAME : The last two characters in the Stream ID, e.g. Z2.
STATION_NAME : The first four characters in the Stream ID.
SENSOR_SERIAL : The System ID.
CHANNEL_NUMBER : 1 for Zn streams; 2 for Nn streams; 3 for En
streams; 4 – 19 for the 16 Mux channels Mn, adding four to the Mux
channel number (e.g. stream M8 will appear as 12).
Status streams are recorded as plain text, as for GCF files.
9.3 Playback
9.3.1 GCF files
To replay a stored GCF file or files:
1. Select File Replay Files… → from Scream!'s main menu and
select the data you want to replay, or drag GCF files from a
Windows Explorer window into Scream!'s main window.
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