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Click to see photo album.

INTRODUCTION

The survey was conducted from Sept. 11 to Sept. 24, 2001, onboard University of Bergen research vessel "Haakon Mosby". It was the first use of the digital 3 km 7 120 ch N-3 streamer.

Link to original project web page (2006).

DATA, LOG FILES, FORMAT DESCRIPTION

Data and log files

Table 1: Data, log files

Link to raw data

Format description Survey Computer (EIVA) log files

Shot event files

• File name example: 0120_linjex.log, where x is the profile number; "0120" means survey #20 in 2001
• Description: Shotpoint log files. They also include gravity, magnetometer and normally depth data, but - IMPORTANT - grav data should be taken from the log files generated by the gravity meter.
• Logging machine: Survey Computer (= EIVA)
• Logging interval: Each shot point

Shot (= Event) files; format example:

 Time in UTC pos WGS84 UTM zone 32
 Event Time Easting Northing St.d. Gyro Dal Dol Kp Data
 ----------------------------------------------------------------------------------
 000001 20:19:27 0645265.93 08712571.46 10.00 226.8 -0398.41 000.56 -00.398 Filtered 0232.70 14624.99 14624.99 2001.00 54519.00 54519.00
 000002 20:22:19 0644962.77 08712312.81 09.00 229.3 00000.08 002.25 000.000 Filtered 0238.00 14624.56 14624.56 2001.00 6875.00 6875.00
 Start Recording:
 000003 20:22:40 0644924.61 08712280.51 09.00 227.7 00050.08 002.66 000.050 Filtered 0239.10 14624.51 14624.51 2001.00 6876.00 6876.00
 000004 20:23:01 0644887.17 08712247.47 09.00 227.7 00100.01 002.04 000.100 Filtered 0240.00 14624.45 14624.45 2001.00 54520.00 54520.00 

 Field no. Example        Parameter                Notes
 ------------------------------------------------------------------------------------------
    1      000003         Shot (event) number 
    2      20:22:40       Time
    3      0644924.61     UTM Easting              Refered to antenna position in mast.
    4      08712280.51    UTM Northing             Refered to antenna position in mast.
    5      09.00          Standard deviation        
    6      227.7          Gyro compass reading
    7      00050.08       DAL                      Distance along line [m]
    8      002.66         DOL                      Distance off line [m]
    9      000.050        KP                       Kilometer post
   10      Filtered                                (check)
   11      0239.10        Depth                    From EK500 Echo Sounder
   12      52816.00       Magnetometer             (Length of mag tow fish cable - check!)
   13      12683.04       Gravitymeter             (Check - filtered, raw??)

Table 2. Shot (event) file format description.

Logging of depth, gravity- and magnetometer data every 10 seconds

Format example:

 Tid i UTC pos WGS 84 UTM sone 32
 Time;Filtered vessel position: East;North;Lat;Long;gravimeterdata;Magnetometerdata;
 20:15:51 11.09.2001; 645632.1110;8712899.1428; 078°24.954311'; 015°30.566050'; 14625.9100; 54511.0000
 20:16:00 11.09.2001; 645616.2427;8712886.0626; 078°24.948271'; 015°30.519964'; 14625.8600; 54513.0000
 20:16:10 11.09.2001; 645598.7942;8712871.4546; 078°24.941510'; 015°30.469222'; 14625.8100; 54514.0000 

NOTE: OCEAN DEPTH EXCEEDING RANGE OF SENSOR, RESULTING IN ERRENOUS READINGS, MIXED WITHIN GRAV-MAG DATA

 Field no.   Example          Parameter           Notes
 --------------------------------------------------------
    1        20:15:51         Time
    2        11.09.2001       Date
    3        645632.1110      UTM Easting
    4        8712899.1428     UTM Northing
    5        078°24.954311'   Latitude
    6        015°30.566050'   Longitude
    7        14625.9100       Gravity
    8        54511.0000       Magnetometer 

Table 3. 10 second interval log file format description.

LIST OF SEG-Y DATA DVDs

Link to list

PHOTO ALBUM

Link to photo album, credit IFG students and M. Vanneste, Department of Geology, University of Tromsø.

DATA / TAPE HANDLING

Link to original web page.

Recording parameters

• Data acquisition system: Geco Triacq, Nessie-3 streamer
• Number of channels: 240
• Number of auxilary channels: 0
• Number of samples per trace: 6144
• Sampling interval: 2 ms
• NPD Survey designation: "UIB-SV-01"

From field tape in SEG-D to SEG-Y on Exabyte tape

Conversion of raw data in DEG-D from 3480 tape to SEG-Y on Exabyte followed two different procedures. The first procedure was abandoned when release 35 of Seismic Unix permitted reading of SEG-D from files.

1. Procedure 1 (applies to data from line no. 2, 5 and 6)
   1. Data copied from the original raw tapes (3480 type) to DLT tape using the Triacq "TapeUtil" program; the DLT drive working under the Triacq SUN machine.
   2. The individual shotfiles extracted from these DLT tapes and written to disk files using a script les-dlt.sh. The DLT reading took place on a Linux PC box with our second DLT tapedrive.
   3. The individual shot files written to Exabyte tape using a script described here.
   4. Exabyte shot files (still in SEG-D) read into Promax, demultiplexed and written to tape in SEG-Y format.
2. Procedure 2 (applies to all other lines)
   1. Data copied from the original raw tapes (3480 type) to disk files on the Triacq SUN machine, in so-called Tape Image Format (TIF). Each tape yields one TIF file.
   2. TIF files transferred to "pandora" (a SUN machine at IFJ) and Linux PC box and put into directories with profile names.
   3. Used a program called "tifread" to extract individual shotfiles from TIF files. Programmer credits: Kristian Hiim.
      • Header file tif.h
      • tifread.cc
   4. Script to demux SEG-D and write SEG-Y to tape. Two computers were used in parallell, the PC Linux box and "pandora".
      • PC Linux box tape writing script (called write_tape)
      • Pandora tape writing scripts (called e.g. write_tape-P21-A for the first file on profile A)
   5. SEG-Y EBCDIC- and binary header files (called header and binary)
      • On PC Linux box
      • On pandora

Tape information

Demux'ed data in SEG-Y format on Exabyte:

• Exabyte drives:
  • On Linux PC box: Exabyte Corp. mod. 8505XLS
  • On "pandora": ........
• Written with variable block size? YES
• Media specs
  • Mfr.: Sony
  • Model QGD160M
  • Capacity: 7.0 GByte
  • Length: 160m

Tape archiving

• Field data, SEG-D-II format on 3480 tape cassettes: Stored at IFJ
• Demux'ed SEG-Y data: One set of Exabyte tapes, stored at NPD
• Tape Image Format (TIF) files on disk, one TIF-file for every field data tape, stored as follows:
  • Two sets of TIF-files stored on AIT tape, one set stored at IFJ, the other stored on external location.
  • One data set on PC harddisk (disk mounted in Linux PC box mentioned above).