bsegy - BSU header format, Fortran Version.
bsegy.inc
Basic Seismic Utilities (BSU) include file, bsegy.inc contains the headers definitions. The common block which transfers header information between the main program and subroutines like bsegin or bsegout is defined in this include file.
BSEGY
DECLARATIONS
Trace Identification Header bytes:
byte hd(240)
1 - 4 Trace sequence number within line
integer*4 tsnl
equivalence (hd(1),tsnl)
5 - 8 Trace sequence number within reel
integer*4 tsnt
equivalence (hd(5),tsnt)
9 - 12 Original Field Record Number
integer*4 ofrn
equivalence (hd(9),ofrn)
13 - 16 Trace number of original field record
integer*4 tnofr
equivalence (hd(13),tnofr)
17 - 20 Energy Source point number
integer*4 espn
equivalence (hd(17),espn)
21 - 24 CDP ensemble number
integer*4 cdp
equivalence (hd(21),cdp)
25 - 28 Trace number within the CDP ensemble
integer*4 tncdp
equivalence (hd(25),tncdp)
29 - 30 Trace ID code (1 = seismic data)
integer*2 tic
equivalence (hd(29),tic)
31 - 32 Number of vertically summed traces yielding trace
integer*2 nvs
equivalence (hd(31),nvs)
33 - 34 Number of horizontally summed traces yielding trace
integer*2 nhs
equivalence (hd(33),nhs)
35 - 36 Data use (1=production; 2=test)
integer*2 duse
equivalence (hd(35),duse)
37 - 40 Shotpoint-Receiver distance (m)
integer*4 idist
equivalence (hd(37),idist)
41 - 44 Station elevation (m)
integer*4 irel
equivalence (hd(41),irel)
45 - 48 Surface elevation of source (m)
integer*4 ishe
equivalence (hd(45),ishe)
49 - 52 Source depth (m)
integer*4 ishd
equivalence (hd(49),ishd)
53 - 56 Datum elevation of receiver
integer*4 delr
equivalence (hd(53),delr)
57 - 60 Datum elevation of source
integer*4 dels
equivalence (hd(57),dels)
61 - 64 Water depth of source
integer*4 wds
equivalence (hd(61),wds)
65 - 68 Water depth of receiver
integer*4 wdr
equivalence (hd(65),wdr)
69 - 70 Scalar multiplier/division for bytes 41-68
integer*2 smul1
equivalence (hd(69),smul1)
71 - 72 Scalar multiplier/division for bytes 73-88
integer*2 smul2
equivalence (hd(71),smul2)
73 - 76 Shotpoint coordinate - x (East positive)
integer*4 ishlo
equivalence (hd(73),ishlo)
77 - 80 Shotpoint coordinate - y (North positive)
integer*4 ishla
equivalence (hd(77),ishla)
81 - 84 Receiver coordinate - x (East positive)
integer*4 irlo
equivalence (hd(81),irlo)
85 - 88 Receiver coordinate - y (North positive)
integer*4 irla
equivalence (hd(85),irla)
89 - 90 Coordinate units (1 = meters; 2 = seconds of arc)
integer*2 cunits
equivalence (hd(89),cunits)
91 - 92 Weathering velocity (m/s?)
integer*2 wvel
equivalence (hd(91),wvel)
93 - 94 Subweathering velocity (m/s?)
integer*2 swvel
equivalence (hd(93),swvel)
95 - 96 Uphole time at source
integer*2 utimes
equivalence (hd(95),utimes)
97 - 98 Uphole time at group
integer*2 utimeg
equivalence (hd(97),utimeg)
99 - 100 Source static correction (ms?)
integer*2 sstati
equivalence (hd(99),sstati)
101 - 102 Group static
integer*2 gstati
equivalence (hd(101),gstati)
103 - 104 Total static
integer*2 tstati
equivalence (hd(103),tstati)
105 - 106 Lag time A
integer*2 istime
equivalence (hd(105),istime)
107 - 108 Lag time B
integer*2 ibtime
equivalence (hd(107),ibtime)
109 - 110 Delay recording time (reduced start time) (msec)
integer*2 ictime
equivalence (hd(109),ictime)
111 - 112 Mute start time
integer*2 mtimes
equivalence (hd(111),mtimes)
113 - 114 Mute end time
integer*2 mtimee
equivalence (hd(113),mtimee)
115 - 116 Number of samples in this trace
integer*2 length
equivalence (hd(115),length)
117 - 118 Sample interval in microseconds for this trace
integer*2 isi
equivalence (hd(117),isi)
119 - 120 Gain type (1=fixed; 2=binary; 3=floating)
integer*2 gaint
equivalence (hd(119),gaint)
121 - 122 Gain constant
integer*2 gc
equivalence (hd(121),gc)
123 - 124 Instrument or initial gain in DB
integer*2 gidb
equivalence (hd(123),gidb)
125 - 126 Correlated (1=no; 2=yes)
integer*2 tcorr
equivalence (hd(125),tcorr)
127 - 128 Start sweep frequency (hz)
integer*2 tsswee
equivalence (hd(127),tsswee)
129 - 130 End sweep frequency (hz)
integer*2 teswee
equivalence (hd(129),teswee)
131 - 132 Sweep length in milliseconds
integer*2 tsleng
equivalence (hd(131),tsleng)
133 - 134 Sweep type
integer*2 tstype
equivalence (hd(133),tstype)
135 - 136 Sweep trace taper in msec at start
integer*2 tstts
equivalence (hd(135),tstts)
137 - 138 Sweep trace taper in msec at end
integer*2 tstte
equivalence (hd(137),tstte)
139 - 140 Taper type
integer*2 tttype
equivalence (hd(139),tttype)
141 - 142 Antialias filter frequency
integer*2 aif
equivalence (hd(141),aif)
143 - 144 Antialias filter slope
integer*2 ais
equivalence (hd(143),ais)
145 - 146 Notch filter frequency
integer*2 nif
equivalence (hd(145),nif)
147 - 148 Notch filter slope
integer*2 nis
equivalence (hd(147),nis)
149 - 150 Low cut frequency
integer*2 flc
equivalence (hd(149),flc)
151 - 152 High cut frequency
integer*2 fhc
equivalence (hd(151),fhc)
153 - 154 Low cut slope
integer*2 slc
equivalence (hd(153),slc)
155 - 156 High cut slope
integer*2 shc
equivalence (hd(155),shc)
157 - 158 Shot Time - year
integer*2 tyear
equivalence (hd(157),tyear)
159 - 160 Shot Time - day
integer*2 tday
equivalence (hd(159),tday)
161 - 162 Shot Time - hour of day (24 hour clock)
integer*2 thour
equivalence (hd(161),thour)
163 - 164 Shot Time - minute of hour
integer*2 tmin
equivalence (hd(163),tmin)
165 - 166 Shot Time - second of minute
integer*2 tsec
equivalence (hd(165),tsec)
167 - 168 Time basis code (2 = GMT)
integer*2 tbcode
equivalence (hd(167),tbcode)
169 - 170 Trace weigthing factor
integer*2 twf
equivalence (hd(169),twf)
171 - 172 Geophone group number on roll switch first
position
integer*2 ggrp1
equivalence (hd(171),ggrp1)
173 - 174 Geophone group number, trace position 1 on field
record
integer*2 ggtp
equivalence (hd(173),ggtp)
175 - 176 Time code translator error light
integer*2 errlt
equivalence (hd(175),errlt)
177 - 178 Distance-azimuth calculation algorithm
integer*2 daca
equivalence (hd(177),daca)
179 - 180 Earth dimension code
integer*2 edc
equivalence (hd(179),edc)
181 - 184 (BSEGY First Break Picks)
integer*4 mst
equivalence (hd(181),mst)
185 - 186 Source polarization azimuth from North (degrees)
E=90
integer*2 shtazi
equivalence (hd(185),shtazi)
187 - 188 Charge size in grams
integer*2 charge
equivalence (hd(187),charge)
189 - 190 Shot polarization angle from vertical (degrees)
Down=180
integer*2 shtver
equivalence (hd(189),shtver)
191 - 192 Shot time - Day
integer*2 sday
equivalence (hd(191),sday)
193 - 194 Shot time - Hour
integer*2 shour
equivalence (hd(193),shour)
195 - 196 Shot time - Minute
integer*2 smin
equivalence (hd(195),smin)
197 - 198 Shot time - Sec
integer*2 sseco
equivalence (hd(197),sseco)
199 - 202 Shot time - Microsecond (problem alignment, long
int)
integer*2 ssmic1
equivalence (hd(199),ssmic1)
Other half
integer*2 ssmic2
equivalence (hd(201),ssmic2)
203 - 204 Azimuth of receiver from shot (degrees)
integer*2 azimut
equivalence (hd(203),azimut)
205 - 206 Geophone polarization Azimuth of axis (degrees)
E=90
integer*2 geoazi
equivalence (hd(205),geoazi)
207 - 208 Geophone polarization angle of axis from vertical
integer*2 geover
equivalence (hd(207),geover)
209 - 212 Time to be added to trace time to get trace start
time
integer*4 ttrace
equivalence (hd(209),ttrace)
213 - 216 Recording instrument number
character*4 scrs
equivalence (hd(213),scrs)
217 - 220 Deployment name
character*4 deploy
equivalence (hd(217),deploy)
221 - 224 Shotpont name
character*4 spname
equivalence (hd(221),spname)
225 - 228 Receiver site name
character*4 rstnam
equivalence (hd(225),rstnam)
229 - 332 Shot name
character*4 shotid
equivalence (hd(229),shotid)
233 - 236 Line name
character*4 lineid
equivalence (hd(233),lineid)
237 - 240 Geophone orientation
character*4 geoor
equivalence (hd(237),geoor)
Note: bytes
181-240 are unassigned or for optional use as defined by
Berry et al. (1975)-"Digital Tape
Standards"-SEG
bsegy.inc
The file is located in bsu-3.0.3/src/Fort/include/ directory.
bsegin(3), bsegout(3), chktrc(3)
Memory alignment problem developed on bytes 199-202. This seems to work.
Copyright © 2024 by Paul Michaels
This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
P. Michaels, PE. <[email protected]>