Tom B. convinced me that we should archive the onshore-offshore Reftek data in reduced travel time, not raw time. This cuts the data volume considerably. By doing this, we can pack the data into far fewer tapes. We're going to take advantage of the IRIS-DMC to convert the Reftek field data into usable seismograms in common station format. This effort will happen later this month (after AGU). If things go well, there will be two products: (1) a set of archive tapes of all the data, (2) a set of tapes where the data is resorted by ship profile and by land array. The data on the 2nd set of tapes can be saved in a couple of different forms. # output tapes vary from 17 to 49, with ease of access being variable. thoughts? -david PRODUCT 1: ARCHIVE TAPES For each station gather, all Ewing airgun sources. One station = 22,128 seismograms @ 30 sec, 100 sps = 270 MB. 167 stations @ 7 stations/tape -> ~24 SEGY 8 mm tapes . PRODUCT 2: USABLE FOR RESEARCH TAPES Data sorted by ship profile and land array. One seismogram = 20 sec reduced, 100 sps = 8240 bytes/trace Line airgun size Seal Beach Northridge El Segundo shots gather (80 gaths) (47 gaths) (40 gaths) (traces) (MB) (MB/tapes) (MB/tapes) (MB/tapes) 01 653 5.4 430.5/1 252.9/1 215.2/1 01R 2310 19.0 1522.8/1 894.6/1 761.4/1 01X 848 7.0 559.0/1 328.4/1 279.5/1 01Y 968 8.0 638.1/1 374.9/1 319.1/1 TR1 976 8.0 643.4/1 378.0/1 321.7/1 03 2446 20.2 1612.4/1 947.3/1 806.2/1 03R 2488 20.5 1640.1/1 963.6/1 820.0/1 TR2 394 3.2 259.7/1 152.6/1 129.9/1 02 3117 25.7 2054.7/2 1207.2/1 1027.4/1 02R 722 5.9 475.9/1 279.6/1 238.0/1 02X 1296 10.7 854.3/1 501.9/1 427.2/1 02Y 1519 12.5 1001.3/1 588.3/1 500.7/1 02Z 783 6.5 516.2/1 303.2/1 258.1/1 TR3 1074 8.8 708.0/1 415.9/1 354.0/1 01A 1227 10.1 808.8/1 475.2/1 404.4/1 01B 1307 10.8 861.6/1 506.2/1 430.8/1 sub 14586.8/17 8569.7/16 7293.4/16 Total 22,128 = 30,449.9 MB = 49 tapes. This could be compacted into only 17 tapes. Alternatively, the inline recordings can be kept on individual tapes and the cross-line data can be compacted tapes. This would make for a total of approx. 30 tapes.