Go to https://cgiss.boisestate.edu/ pm/BSU
Check the BSU Campus check box and then submit button. The data are
downloaded as archive ID-100.zip. Unzip the archive and go to Example
1. We begin with the program bnez.
{bnezrun} #!/bin/bash # Script gofirst bnez 000001.nez 13 2 1 0 0 0 01 0 0 0 1 mv bnez.lst bnezshots.lst bnez 000002.nez 30 1 14 0 0 0 01 0 1 0 1 mv bnez.lst bnezphones.lst mv 000001.nez LAB001.nez cat 000002.nez >>LAB001.nez rm 000002.nezbnezrun
The first command, bnez, automates the generation of source positions for an NEZ survey file (Northing=Y, Easting=X, Elevation=Z). Here is the online help when you type bnez -h
{bnezhelp} bnez outfile n-points tag so yo xo zo ido dy dx dz did outfile = output file name (ex. aaaa0001.nez n-points = number of survey points to generate tag = 1 tag=VP = 2 tag=SP so = first value of sequence number yo = northing of first point xo = easting of first point zo = elevation of first point ido = initial ID number dy = spacing between points in north direction dx = spacing between points in east direction dz = spacing in elevation between points did = interval in ID between pointsbnezhelp
The contents of the file, 000001.nez, contains 5 columns,
[ID,Y,X,Z,Tag] and is as follows:
1 0.000000 0.000000 0.000000 SP001 2 0.000000 0.000000 0.000000 SP002 3 0.000000 0.000000 0.000000 SP003 4 0.000000 0.000000 0.000000 SP004 5 0.000000 0.000000 0.000000 SP005 6 0.000000 0.000000 0.000000 SP006 7 0.000000 0.000000 0.000000 SP007 8 0.000000 0.000000 0.000000 SP008 9 0.000000 0.000000 0.000000 SP009 10 0.000000 0.000000 0.000000 SP010 11 0.000000 0.000000 0.000000 SP011 12 0.000000 0.000000 0.000000 SP012 13 0.000000 0.000000 0.000000 SP013
One generates a second file for the geophone locations, 000002.nez, and then the two NEZ files are concatenated into a merged file LAB001.nez. Note the source did not move for all 13 shot record efforts. The second bnez command produces file 000002.nez shown below:
14 0.000000 0.000000 0.000000 VP001 15 0.000000 1.000000 0.000000 VP002 16 0.000000 2.000000 0.000000 VP003 17 0.000000 3.000000 0.000000 VP004 18 0.000000 4.000000 0.000000 VP005 19 0.000000 5.000000 0.000000 VP006 20 0.000000 6.000000 0.000000 VP007 21 0.000000 7.000000 0.000000 VP008 22 0.000000 8.000000 0.000000 VP009 23 0.000000 9.000000 0.000000 VP010 24 0.000000 10.000000 0.000000 VP011 25 0.000000 11.000000 0.000000 VP012 26 0.000000 12.000000 0.000000 VP013 27 0.000000 13.000000 0.000000 VP014 28 0.000000 14.000000 0.000000 VP015 29 0.000000 15.000000 0.000000 VP016 30 0.000000 16.000000 0.000000 VP017 31 0.000000 17.000000 0.000000 VP018 32 0.000000 18.000000 0.000000 VP019 33 0.000000 19.000000 0.000000 VP020 34 0.000000 20.000000 0.000000 VP021 35 0.000000 21.000000 0.000000 VP022 36 0.000000 22.000000 0.000000 VP023 37 0.000000 23.000000 0.000000 VP024 38 0.000000 24.000000 0.000000 VP025 39 0.000000 25.000000 0.000000 VP026 40 0.000000 26.000000 0.000000 VP027 41 0.000000 27.000000 0.000000 VP028 42 0.000000 28.000000 0.000000 VP029 43 0.000000 29.000000 0.000000 VP030
Once the merged NEZ file has been created, we can then run program gensetg. This is an interactive program, and the following is a log of the execution captured from the terminal:
$ gensetg |----------------------------------------| | Copyright (C) 2009 P. Michaels | | All rights reserved | | See GNU General Public License | |----------------------------------------| gset: TIME: 15:44:00 DATE: 29/Dec/2016 SHOTS: --------------------------- Enter first shot file NAME number 1001 Enter last shot file NAME number 1013 Enter first SP label NUMBER 01 Enter increment for SP label NUMBER 1 PHONES: --------------------------- Enter number of BLOCKS to define channels 1 BLOCK Number------- 1 Channels (1) through (?) Enter last channel for this block 30 Enter first label VP NUMBER for this block 01 Enter label VP increment for this block 1
The result of gensetg is the creation of 2 files, shots.txt, which relates the data sets to the shot locations, and phones.txt, which relates the channel to VP location in the NEZ file.
File shots.txt is as follows:
1001.seg SP001 1002.seg SP002 1003.seg SP003 1004.seg SP004 1005.seg SP005 1006.seg SP006 1007.seg SP007 1008.seg SP008 1009.seg SP009 1010.seg SP010 1011.seg SP011 1012.seg SP012 1013.seg SP013
File phones.txt is as follows:
01 VP001 02 VP002 03 VP003 04 VP004 05 VP005 06 VP006 07 VP007 08 VP008 09 VP009 10 VP010 11 VP011 12 VP012 13 VP013 14 VP014 15 VP015 16 VP016 17 VP017 18 VP018 19 VP019 20 VP020 21 VP021 22 VP022 23 VP023 24 VP024 25 VP025 26 VP026 27 VP027 28 VP028 29 VP029 30 VP030
We conclude by transferring the geometry to the seismic traces. The following script is used in this case:
{bnezrun} #!/bin/bash if ! [ -e LAB001.nez ] then echo "LAB001.nez missing, run gofirst" else if ! [ -e shots.txt ] then echo "shots.txt missing, run gosecond (gensetg)" else if ! [ -e phones.txt ] then echo "phones.txt missing, run gosecond (gensetg)" else # convert SEG2 files to BSEGY (*.seg), headers not final FILES=`ls -1 *.DAT |sort ` for f in $FILES; do egg2seg $f; done rm *.lst # apply correct geometry to *.seg files created above setgeom shots.txt phones.txt LAB001.nez #rename files (like setg1001.seg to 1001.seg) for f in $FILES; do NAME=`basename $f .DAT` mv setg${NAME}.seg ${NAME}.seg done fi fi fibnezrun
The after checking for needed files, the bash script loops through data files, 1001.DAT through 1013.DAT converting these SEG-2 files recorded with the EGG Geometrics. The result is files 1001.seg through 1013.seg are created, but do not yet have the correct geometry. Program, setgeom, runs and applies the correct geometry to the BSEGY files, setg1001.seg through setg1013.seg. The last step in the script renames the files back to 1001.seg through 1013.seg.
We can view the headers created using the bdump program. For example, the command, bdump 1001.seg 0 produces the following text file. Note that the above process corrects the locations of sources and receivers. The program egg2seg, has inserted the trace length, filters, shot date and time. The assumption of shot and receiver orientation (180 degrees from vertical) is a default setting and may need to be corrected. For that, program bhed can be used.
{dumplist2} |-------------------------------| | PARTIAL SEGY HEADER DUMP | | | | 1001.seg | | | |-------------------------------| ----------------------------------------------------------------------------------- Length = 2000 samples | Shot Elevation = 0.0 Sample Interval = 0.00025 sec. | Shot Depth = 0.0 Delay Time = 0 msec. | Up Hole Time = 0 msec Low Cut Filter = 0 Hz. | Shot X-COORD = 0.00 High Cut Filter = 1000 Hz. | Shot Y-COORD = 0.00 Line ID: 001 | Shot Date (year.moday) = 2004.0406 Shot Orientation: | Shot Time (hr:min) = 14:16 Azimuth= 0 Deg. Vertical=180 Deg.| Charge Size (grams)= 0 ----------------------------------------------------------------------------------- TRACE|SHOT| STATION | OFFSET| RECEIVER |VERT|1STBRK|K-GAIN|AZI|VER| # |REC.|SHOT REC| | ELEV. X-COORD Y-COORD|FOLD|(SEC.)| (dB) | | | -----|----|---------|-------|----------------------------|--|------|------|---|---| 1 | 1| 001 001| 0.00| 0.00 0.00 0.00| 2|0.0000| 24 | 0|180| 2 | 1| 001 002| 1.00| 0.00 1.00 0.00| 2|0.0000| 24 | 0|180| 3 | 1| 001 003| 2.00| 0.00 2.00 0.00| 2|0.0000| 24 | 0|180| 4 | 1| 001 004| 3.00| 0.00 3.00 0.00| 2|0.0000| 24 | 0|180| 5 | 1| 001 005| 4.00| 0.00 4.00 0.00| 2|0.0000| 24 | 0|180| 6 | 1| 001 006| 5.00| 0.00 5.00 0.00| 2|0.0000| 24 | 0|180| 7 | 1| 001 007| 6.00| 0.00 6.00 0.00| 2|0.0000| 24 | 0|180| 8 | 1| 001 008| 7.00| 0.00 7.00 0.00| 2|0.0000| 24 | 0|180| 9 | 1| 001 009| 8.00| 0.00 8.00 0.00| 2|0.0000| 24 | 0|180| 10 | 1| 001 010| 9.00| 0.00 9.00 0.00| 2|0.0000| 24 | 0|180| 11 | 1| 001 011| 10.00| 0.00 10.00 0.00| 2|0.0000| 24 | 0|180| 12 | 1| 001 012| 11.00| 0.00 11.00 0.00| 2|0.0000| 24 | 0|180| 13 | 1| 001 013| 12.00| 0.00 12.00 0.00| 2|0.0000| 24 | 0|180| 14 | 1| 001 014| 13.00| 0.00 13.00 0.00| 2|0.0000| 24 | 0|180| 15 | 1| 001 015| 14.00| 0.00 14.00 0.00| 2|0.0000| 24 | 0|180| 16 | 1| 001 016| 15.00| 0.00 15.00 0.00| 2|0.0000| 24 | 0|180| 17 | 1| 001 017| 16.00| 0.00 16.00 0.00| 2|0.0000| 24 | 0|180| 18 | 1| 001 018| 17.00| 0.00 17.00 0.00| 2|0.0000| 24 | 0|180| 19 | 1| 001 019| 18.00| 0.00 18.00 0.00| 2|0.0000| 24 | 0|180| 20 | 1| 001 020| 19.00| 0.00 19.00 0.00| 2|0.0000| 24 | 0|180| 21 | 1| 001 021| 20.00| 0.00 20.00 0.00| 2|0.0000| 24 | 0|180| 22 | 1| 001 022| 21.00| 0.00 21.00 0.00| 2|0.0000| 24 | 0|180| 23 | 1| 001 023| 22.00| 0.00 22.00 0.00| 2|0.0000| 24 | 0|180| 24 | 1| 001 024| 23.00| 0.00 23.00 0.00| 2|0.0000| 24 | 0|180| 25 | 1| 001 025| 24.00| 0.00 24.00 0.00| 2|0.0000| 24 | 0|180| 26 | 1| 001 026| 25.00| 0.00 25.00 0.00| 2|0.0000| 24 | 0|180| 27 | 1| 001 027| 26.00| 0.00 26.00 0.00| 2|0.0000| 24 | 0|180| 28 | 1| 001 028| 27.00| 0.00 27.00 0.00| 2|0.0000| 24 | 0|180| 29 | 1| 001 029| 28.00| 0.00 28.00 0.00| 2|0.0000| 24 | 0|180| 30 | 1| 001 030| 29.00| 0.00 29.00 0.00| 2|0.0000| 24 | 0|180|dumplist2