Large-N work instructions

Last modified by oktahvo@helsinki_fi on 2024/01/16 08:00

In order to speed up data processing of the collected Large-N data, following is needed:

  • For every project, a Survey geometry file is needed, in SPS 1.0, SPS 2.0 or SP1 format.

It is highly recommended that the receivers are installed so, that the distance between the devices are 5 meters, or over.

It is possible to gather data with tighter grid than 5 meters.

  • In that case an additional device location file is needed.

The location file consists of:


    • device serial number,
    • line number,
    • station number and
    • device deployment time.

We will provide you with the Deployment time and the device serial number, in addition of example file, but the creation of the location file is based on clients notes of the measurement.

For active surveys, the following information is needed:

(Please refer to the GEM User Manual chapter 4.12.4)

  • Source related parameters (stacks, sweep information, pilot, etc.)
  • Trigger file configuration
  • Auxiliary channels configuration 
  • File name components 
  • Type of gather (shot, receiver or continuous)
  • SEG type (SEGD rev 2 or 3), SEG-Y (rev 0 or 1), 
  • Process type to be used
  • Record length 
  • Stack setup 
  • Type of correlation

For best results, we hope to receive detailed notes of the measurement.

A discussion between PI and Flex-Epos technicians for additional information is also possible