SEG-D, Rev 3.0 SEG Field Tape Standards September, 2014 Table of Contents 1.0 INTRODUCTION ................................................................................................. 5 1.1 CONTROLLING ORGANIZATION................................................................................. 6 2.0 CHANGES INTRODUCED IN REVISION 3.0 ................................................... 7 2.1 CHANGES INTRODUCED IN REVISION 2.1 ................................................................ 10 2.2 CHANGES INTRODUCED IN REV 2.0 ........................................................................ 11 2.3 CHANGES INTRODUCED IN REV 1 ........................................................................... 13 3.0 FORMAT OVERVIEW ........................................................................................... 17 3.1 SEG-D TIMESTAMP ........................................................................................... 25 3.2 MULTI-COMPONENT DATA ................................................................................ 28 3.3 EXTENDED RECORDING MODE .......................................................................... 28 3.4 PERMANENT RECORDING SYSTEMS ................................................................... 28 3.5 TIME DRIFT ........................................................................................................ 29 3.6 POSITIONS IN SEG-D ......................................................................................... 29 4.0 SEG-D, REV 3.0 STRUCTURE .............................................................................. 31 4.1 REV 3.0 STORAGE UNIT LABEL (TAPE LABEL) ................................................. 31 4.2 REV 3.0 TABLE OF CONTENTS (TOC) FILE (OPTIONAL) ................................... 33 4.2.1 TOC Header .................................................................................................. 34 4.2.2 TOC Record Entry ........................................................................................ 36 4.2.3 Using the TOC with SEG-D on disk ............................................................. 37 5.0 HEADER BLOCKS .................................................................................................. 39 5.1 GENERAL HEADERS (GENERAL HEADER BLOCK #1, #2 AND #3 ARE REQUIRED) .. 39 5.2 SCAN TYPE HEADERS ............................................................................................. 41 5.3 DEMUX TRACE HEADER (REQUIRED) ..................................................................... 42 5.4 EXTENDED HEADER (OPTIONAL) ............................................................................ 44 5.5 EXTERNAL HEADER (OPTIONAL) ............................................................................ 44 5.6 GENERAL TRAILER (OPTIONAL) .............................................................................. 44 5.6.1 Edit (SEG-D Trace Edit v1.0) ....................................................................... 45 5.6.2 Navigation data backup ................................................................................. 47 5.6.3 Text Comment............................................................................................... 48 5.6.4 Observer log .................................................................................................. 48 5.6.5 User defined .................................................................................................. 48 6.0 DATA BODY ............................................................................................................. 49 6.1 DATA RECORDING METHOD ................................................................................... 49 6.2 DSM FACTOR CALCULATION AND PHYSICAL UNIT ................................................ 54 6.3 SENSOR CALIBRATION............................................................................................. 56 7.0 HEADER TABLES ............................................................................................. 58 7.1 GENERAL HEADER BLOCK #1 .................................................................... 58 7.2 GENERAL HEADER BLOCK #2 .................................................................... 59 7.3 GENERAL HEADER BLOCK #3 (TIMESTAMP AND SIZE HEADER) ............... 60 7.4 GENERAL HEADER BLOCK #4 (VESSEL/CREW IDENTIFICATION) (OPTIONAL) 60 7.5 GENERAL HEADER BLOCK #5 (SURVEY AREA NAME) (OPTIONAL) .......... 61 7.6 GENERAL HEADER BLOCK #6 (CLIENT IDENTIFICATION) (OPTIONAL) ..... 62 7.7 GENERAL HEADER BLOCK #7 (JOB IDENTIFICATION) (OPTIONAL) ............ 63 7.8 GENERAL HEADER BLOCK #8 (LINE IDENTIFICATION) (OPTIONAL) .......... 64 ii 7.9 SOURCE DESCRIPTION BLOCK (OPTIONAL) .............................................. 64 7.9.1 VIBRATOR .................................................................................................. 65 7.9.2 EXPLOSIVE ................................................................................................. 65 7.9.3 AIRGUN ....................................................................................................... 66 7.9.4 WATERGUN ................................................................................................ 67 7.9.5 ELECTROMAGNETIC SOURCE ............................................................... 68 7.9.6 OTHER SOURCE ......................................................................................... 69 7.10 ADDITIONAL SOURCE INFO (OPTIONAL) ................................................... 69 7.11 SOURCE AUXILIARY CHANNEL REFERENCE (OPTIONAL) .................... 70 7.12 COORDINATE REFERENCE SYSTEM IDENTIFICATION (CONDITIONAL)72 7.13 POSITION BLOCKS (OPTIONAL) .................................................................... 72 7.14 RELATIVE POSITION BLOCK (OPTIONAL) .................................................. 75 7.15 SCAN TYPE HEADER (CHANNEL SET DESCRIPTOR) .................................... 75 7.16 DEMUX TRACE HEADER ............................................................................. 79 7.17 TRACE HEADER EXTENSION #1................................................................. 80 7.18 SENSOR INFO HEADER EXTENSION (OPTIONAL) ..................................... 80 7.19 TIMESTAMP HEADER (OPTIONAL) ............................................................... 81 7.20 SENSOR CALIBRATION HEADER (OPTIONAL) ........................................... 82 7.21 TIME DRIFT HEADER (OPTIONAL) ................................................................ 83 7.22 ORIENTATION HEADER (OPTIONAL) ........................................................... 83 7.23 MEASUREMENT BLOCK (OPTIONAL) .......................................................... 84 7.24 ELECTROMAGNETIC SRC/RECV DESC BLOCK (OPTIONAL) .................. 85 7.25 GENERAL TRAILER DESCRIPTION BLOCK (OPTIONAL) ......................... 86 8.0 HEADER BLOCK PARAMETERS ................................................................. 87 8.1 GENERAL HEADER, BLOCK #1 ................................................................... 87 8.2 GENERAL HEADER BLOCK #2 .................................................................... 89 8.3 GENERAL HEADER BLOCK #3 (TIMESTAMP AND SIZE HEADER) ............... 91 8.4 GENERAL HEADER BLOCK #4 (VESSEL/CREW IDENTIFICATION) (OPTIONAL) 92 8.5 GENERAL HEADER BLOCK #5 (SURVEY AREA NAME) (OPTIONAL) .......... 92 8.6 GENERAL HEADER BLOCK #6 (CLIENT IDENTIFICATION) (OPTIONAL) ..... 93 8.7 GENERAL HEADER BLOCK #7 (JOB IDENTIFICATION) (OPTIONAL) ............ 93 8.8 GENERAL HEADER BLOCK #8 (LINE IDENTIFICATION) (OPTIONAL) .......... 93 8.9 SOURCE DESCRIPTION BLOCK (OPTIONAL) ............................................. 94 8.9.1 VIBRATOR .................................................................................................. 94 8.9.2 EXPLOSIVE ................................................................................................. 96 8.9.3 AIRGUNs...................................................................................................... 98 8.9.4 WATERGUN .............................................................................................. 100 8.9.5 ELECTROMAGNETIC .............................................................................. 101 8.9.6 OTHER SOURCE ....................................................................................... 103 8.10 ADDITIONAL SOURCE INFO (OPTIONAL) ................................................. 105 8.11 SOURCE AUXILIARY CHANNEL REFERENCE (OPTIONAL) ................... 105 8.12 COORDINATE REFERENCE SYSTEM IDENTIFICATION (CONDITIONAL)107 8.13 POSITION BLOCKS (OPTIONAL) .................................................................. 107 8.14 RELATIVE POSITION BLOCK (OPTIONAL) ................................................ 110 8.15 SCAN TYPE HEADER (CHANNEL SET DESCRIPTOR) .................................... 111 8.16 CHANNEL SET DESCRIPTOR .................................................................... 111 8.17 DEMUX TRACE HEADER ........................................................................... 115 8.18 TRACE HEADER EXTENSION #1............................................................... 116 8.19 SENSOR INFO HEADER EXTENSION (OPTIONAL) ................................... 118 8.20 TIMESTAMP HEADER (OPTIONAL) ............................................................. 119 8.21 SENSOR CALIBRATION HEADER (OPTIONAL) ......................................... 119 iii 8.22 TIME DRIFT HEADER (OPTIONAL) .............................................................