From aj.schaeffer at gmail.com Wed Jul 6 07:19:25 2011 From: aj.schaeffer at gmail.com (Andrew Schaeffer) Date: Wed, 6 Jul 2011 15:19:25 +0100 Subject: [SAC-HELP] Difference in 101.3b vs 101.4 with gcp rotation Message-ID: Hello, I am trying to resolve a difference between the SAC versions 101.3b and 101.4. *In 101.3b*: I am performing "rotate to gcp" on a north and east component seismogram, and writing out the radial and transverse components: r s1.dn s1.de rotate to gcp ->If I list the header (lh) at this point, the KCMPNM header value is now empty (ie doesn't show up). write s1.dr s1.dt quit If I start sac again, and read in the dr and dt components, they now have the KCMPNM header value, with "Q" for both components. If I repeat the same procedure in 101.4, the KCMPNM header value remains empty, even after writing the seismograms and reloading them. Can anyone confirm whether this is the expected behaviour (ie the difference between the two versions), or what their version is doing? many thanks, Andrew -------------- next part -------------- An HTML attachment was scrubbed... URL: From savage at uri.edu Wed Jul 6 08:08:45 2011 From: savage at uri.edu (Brian Savage) Date: Wed, 6 Jul 2011 11:08:45 -0400 Subject: [SAC-HELP] Difference in 101.3b vs 101.4 with gcp rotation In-Reply-To: References: Message-ID: <83162B73-7419-485F-B937-224EB60FD836@uri.edu> Andrew, What you are seeing is correct. In previous versions of SAC, 101.3 and earlier: If the station name (kstnm) is not defined, it would default to "sta" If the channel name (kcmpnm) is not defined, it would default to "Q" The stations and channel names were only changed on read. It was added a long while ago to "Disallow undefined kstnm and kcmpnm". We removed this in 101.4. It was considered to be confusing behavior. From the HISTORY file: * BUG FIX: Stations no longer named 'sta' and channels 'Q' by default If you need this, or have scripts/programs that rely on it, you can change the header values to a something you expect. SAC> ch kcmpnm Q or if you know they are radial transverse, you could use SAC> ch kcmpnm BHR For your processing: On the initial read, the fields kcmpnm for both files are probably set to BHN and BHE The ROTATE command sets the kcmpnm fileds to undefined (-12345.0) You write the files out. The kcmpnm is still set as "-12345.0" You read the files back in. On this read the kcmpnm is set to "Q" as 101.3 did not allow a undefined kcmpnm field. If this change caused havoc, we apologize. I hope this helps. Brian Savage savage at uri.edu Example run using 101.4: SAC> fg seismo SAC> ch cmpinc 90 SAC> ch cmpaz 0 SAC> ch kcmpnm BHN SAC> w tmp.n SAC> ch cmpaz 90 SAC> ch kcmpnm BHE SAC> w tmp.e SAC> read tmp.n tmp.e SAC> lh cmpaz cmpinc az baz kcmpnm columns 2 FILE: tmp.n - 1 ----------- cmpaz = 0.000000e+00 cmpinc = 9.000000e+01 az = 8.814721e+01 baz = 2.718528e+02 kcmpnm = BHN FILE: tmp.e - 2 ----------- cmpaz = 9.000000e+01 cmpinc = 9.000000e+01 az = 8.814721e+01 baz = 2.718528e+02 kcmpnm = BHE SAC> rotate SAC> lh cmpaz cmpinc az baz kcmpnm columns 2 FILE: tmp.n - 1 ----------- cmpaz = 9.185278e+01 cmpinc = 9.000000e+01 az = 8.814721e+01 baz = 2.718528e+02 FILE: tmp.e - 2 ----------- cmpaz = 1.818528e+02 cmpinc = 9.000000e+01 az = 8.814721e+01 baz = 2.718528e+02 SAC> evaluate ( ( &1,baz + 180 ) - &1,cmpaz ) 3.6000000e+02 On Jul 6, 2011, at 10:19 AM, Andrew Schaeffer wrote: > Hello, > > I am trying to resolve a difference between the SAC versions 101.3b and 101.4. > > In 101.3b: > I am performing "rotate to gcp" on a north and east component seismogram, and writing out the radial and transverse components: > r s1.dn s1.de > rotate to gcp > ->If I list the header (lh) at this point, the KCMPNM header value is now empty (ie doesn't show up). > write s1.dr s1.dt > quit > > If I start sac again, and read in the dr and dt components, they now have the KCMPNM header value, with "Q" for both components. > > If I repeat the same procedure in 101.4, the KCMPNM header value remains empty, even after writing the seismograms and reloading them. > Can anyone confirm whether this is the expected behaviour (ie the difference between the two versions), or what their version is doing? > > many thanks, > Andrew > _______________________________________________ > sac-help mailing list > sac-help at iris.washington.edu > http://www.iris.washington.edu/mailman/listinfo/sac-help -------------- next part -------------- An HTML attachment was scrubbed... URL: From snoke at vt.edu Wed Jul 6 16:34:49 2011 From: snoke at vt.edu (Arthur Snoke) Date: Wed, 6 Jul 2011 19:34:49 -0400 (EDT) Subject: [SAC-HELP] printed comment in transfer command Message-ID: For all transfer commands, there is a line printed to the screen: Waveform multiplied by 1.000000 after deconvolution. So far as I can tell it, this line serves no purpose. If any of you know a reason to keep this printed output, please let me know. From snoke at vt.edu Thu Jul 7 19:11:33 2011 From: snoke at vt.edu (Arthur Snoke) Date: Thu, 7 Jul 2011 22:11:33 -0400 (EDT) Subject: [SAC-HELP] SAC with shell script In-Reply-To: References: Message-ID: There wilol be a new help file with examples in version 101.5, which should be out "soon." On Mon, 27 Jun 2011, Januka Attanayake wrote: > Hi, > Is there any possibility that SAC developers could add documentation on > calling SAC within a Shell script to the SAC User guide? This is an area I > repeatedly had problems with and haven't found a robust solution yet. The > external documentation that I have found online haven't been that helpful > either. > > Thank you. > > Januka. > > From jattanayake at yahoo.com Thu Jul 7 19:20:06 2011 From: jattanayake at yahoo.com (Januka Attanayake) Date: Thu, 7 Jul 2011 19:20:06 -0700 (PDT) Subject: [SAC-HELP] SAC with shell script In-Reply-To: References: Message-ID: <1310091606.15714.YahooMailNeo@web162002.mail.bf1.yahoo.com> Thanks a lot Arthur! Januka. ________________________________ From: Arthur Snoke To: Januka Attanayake Cc: sac-help at iris.washington.edu Sent: Thursday, July 7, 2011 10:11 PM Subject: Re: [SAC-HELP] SAC with shell script There wilol be a new help file with examples in version 101.5, which should be out "soon." On Mon, 27 Jun 2011, Januka Attanayake wrote: > Hi, > Is there any possibility that SAC developers could add documentation on > calling SAC within a Shell script to the SAC User guide? This is an area I > repeatedly had problems with and haven't found a robust solution yet. The > external documentation that I have found online haven't been that helpful > either. > > Thank you. > > Januka. > > _______________________________________________ sac-help mailing list sac-help at iris.washington.edu http://www.iris.washington.edu/mailman/listinfo/sac-help -------------- next part -------------- An HTML attachment was scrubbed... URL: From sudesh.ngri at yahoo.com Thu Jul 7 23:30:47 2011 From: sudesh.ngri at yahoo.com (SUDESH KUMAR) Date: Thu, 7 Jul 2011 23:30:47 -0700 (PDT) Subject: [SAC-HELP] seeking help regarding HYPO file format Message-ID: <1310106647.15798.YahooMailNeo@web121212.mail.ne1.yahoo.com> Dear Sir/Madam I am using SAC for seismological analysis for last two years. Recently I am using sac101.3b and got a problem in HYPO file format, I am unable to follow the format of case1. ??????????? case1 ? AMT IPU0? 9 3161424338.00?????? 345.3ISN0?? 0?? 0.0???? (SAC101.3b) case2 ? GDP IPU0? 20116134145.99?????? 46.31ISN0?? 0?? 0.0??????? (early version) In case1, what last? three digit reflects (ie 338.00). I wish to obtain HYPO file format as shown in case2. Please help me out ... thanks? sudesh kumar NGRI HYDERABAD -------------- next part -------------- An HTML attachment was scrubbed... URL: From metin.kahraman at boun.edu.tr Fri Jul 8 02:21:42 2011 From: metin.kahraman at boun.edu.tr (Metin Kahraman) Date: Fri, 08 Jul 2011 12:21:42 +0300 Subject: [SAC-HELP] teminal activation Message-ID: <4E16CC26.70501@boun.edu.tr> Dear SAC users, I run SAC 101.3b under Ubuntu linux. When I read a sac file and plot with p1 command, the pop up waveform window activated but I would like teminal window activated to enter more commands while I am seeing waveform window without click terminal window. Is there anyway do this ? Best wishes, Metin Kahraman From snoke at vt.edu Fri Jul 8 03:04:29 2011 From: snoke at vt.edu (Arthur Snoke) Date: Fri, 8 Jul 2011 06:04:29 -0400 (EDT) Subject: [SAC-HELP] teminal activation In-Reply-To: <4E16CC26.70501@boun.edu.tr> References: <4E16CC26.70501@boun.edu.tr> Message-ID: I use Linux only thrugh ssh so may not fully understand your question, but on the Mac I find that resizing or repositioning the wondows allows me to see the X display while I type in a command window. The X window can be resized using either the window command or (maybe) by using the cursor to resize on the screen. I use a Sun directly only occasionally but still greatly prefer the way Sun handles window management over the Mac and, from what I infer from your note, Linux. On Fri, 8 Jul 2011, Metin Kahraman wrote: > Dear SAC users, > > I run SAC 101.3b under Ubuntu linux. When I read a sac file and plot with p1 > command, the pop up waveform window activated but I would like teminal window > activated to enter more commands while I am seeing waveform window without > click terminal window. > > Is there anyway do this ? > > > Best wishes, > Metin Kahraman > _______________________________________________ > sac-help mailing list > sac-help at iris.washington.edu > http://www.iris.washington.edu/mailman/listinfo/sac-help > From sudesh.ngri at yahoo.com Fri Jul 8 03:49:19 2011 From: sudesh.ngri at yahoo.com (SUDESH KUMAR) Date: Fri, 8 Jul 2011 03:49:19 -0700 (PDT) Subject: [SAC-HELP] Question related to HYPO format using OHPF Message-ID: <1310122159.92464.YahooMailNeo@web121212.mail.ne1.yahoo.com> Dear SAC-users I am picking/marking the phase after opening the OHPF in SAC (ver 101.3b). Earlier also i did the same with older version of SAC (100.0). To my surprise i am getting different formats while working with these versions of SAC. e.g. MTP IPU0? 2 1131423 6.00?????? (using ver 100.0) seems to be fine. MTP IPU0? 2 11314236.00??????? (using ver 101.3b) KBC IPU0? 2 1131422666.00???? (using ver 101.3b) ?????????????????? I am not getting any fixed/proper format like earlier version. So, it is some bug or some new format for Hypo file. Thanks and Regards Sudesh Kumar -------------- next part -------------- An HTML attachment was scrubbed... URL: From Onur.Tan at mam.gov.tr Fri Jul 8 03:58:25 2011 From: Onur.Tan at mam.gov.tr (Onur Tan) Date: Fri, 8 Jul 2011 13:58:25 +0300 Subject: [SAC-HELP] teminal activation In-Reply-To: <4E16CC26.70501@boun.edu.tr> Message-ID: Hi, I think that this is normal window behavior. If the graphic window opens, this becomes the latest activated window for the OS. You must re-click the command terminal window to use it. I open sac graphic window, then re-size this and terminal windows. so I can re-plot my graphs without click any window. I also use ubuntu. o. Dr. Onur TAN ---------------------------------------------- 40.7866N 29.4500E --------- T?B?TAK Marmara Ara?t?rma Merkezi, Yer ve Deniz Bilimleri Enstit?s? TUBITAK Marmara Research Center, Earth and Marine Sciences Institute Gebze - Kocaeli - TURKEY On 08.07.2011 12:21, "Metin Kahraman" wrote: Dear SAC users, I run SAC 101.3b under Ubuntu linux. When I read a sac file and plot with p1 command, the pop up waveform window activated but I would like teminal window activated to enter more commands while I am seeing waveform window without click terminal window. Is there anyway do this ? Best wishes, Metin Kahraman _______________________________________________ sac-help mailing list sac-help at iris.washington.edu http://www.iris.washington.edu/mailman/listinfo/sac-help ________________________________ Bu e-posta mesaj? ve onunla iletilen t?m ekler g?nderildi?i ki?i ya da kuruma ?zel olup, gizli ve ?zel bilgiler i?erebilece?i gibi gizlilik y?k?ml?l??? de ta??yor olabilir. Bu mesajda ve ekindeki dosyalarda bulunan t?m fikir ve g?r??ler sadece adres sahip(ler)ine ait olup, T?B?TAK MAM bu e-posta i?eri?indeki bilgilerin kullan?lmas? nedeniyle hi? kimseye kar?? sorumlu tutulamaz Mesaj?n yetkili al?c?s? veya al?c?s?na iletmekten sorumlu ki?i de?ilseniz, mesaj i?eri?ini ya da eklerini kullanmay?n?z, kopyalamay?n?z, yaymay?n?z, ba?ka ki?ilere y?nlendirmeyiniz ve mesaj? g?nderen ki?iyi derhal uyararak bu mesaj? siliniz. Kurumumuz size, mesaj?n ve bilgilerinin de?i?ikli?e u?ramamas?, b?t?nl???n?n ve gizlili?in korunmas? konusunda garanti vermemekte olup, e-posta i?eri?ine yetkisiz olarak yap?lan m?dahale, vir?s i?ermesi ve/veya bilgisayar sisteminize verebilece?i herhangi bir zarardan da sorumlu de?ildir. This e-mail message, including any attachments, is intended only for the use of the individual or entity to whom it is addressed and may contain confidential, private information as well as the exemption from disclosure. All ideas and opinions in this message and attached files can only belong to the addressee(s) and TUBITAK MRC shall have no liability to any person with regard to the use of the information contained in this message If you are not the intended addressee(s) or responsible person to inform the addressee(s), you are hereby notified that; any use, dissemination, distribution, or copying of this message and attached files is strictly prohibited. Delete the message and notify the sender immediately. TUBITAK MRC do not warrant for the accuracy, completeness of the contents of this email and/or the preservation of confidentiality and shall not be liable for the unauthorized changes made to this message, viruses and/or any damages caused in anyway to your computer system From savage at uri.edu Fri Jul 8 09:29:22 2011 From: savage at uri.edu (Brian Savage) Date: Fri, 8 Jul 2011 12:29:22 -0400 Subject: [SAC-HELP] Question related to HYPO format using OHPF In-Reply-To: <1310122159.92464.YahooMailNeo@web121212.mail.ne1.yahoo.com> References: <1310122159.92464.YahooMailNeo@web121212.mail.ne1.yahoo.com> Message-ID: <6FD75050-2F9F-4123-A6CE-8148F276F682@uri.edu> Dear Sudesh Kumar, The behavior you are seeing is incorrect in version 101.3 and correct in 100.0. The bug was introduced when converting the sac code base to be available on 64 bit machines. There is a fix for this bug in the soon to be released 101.5 version. Brian Savage savage at uri.edu On Jul 8, 2011, at 6:49 AM, SUDESH KUMAR wrote: > Dear SAC-users > > I am picking/marking the phase after opening the OHPF in SAC (ver > 101.3b). Earlier also i did the same with older version of SAC > (100.0). To my surprise i am getting different formats while working > with these versions of SAC. e.g. > > > MTP IPU0 2 1131423 6.00 (using ver 100.0) seems to be fine. > MTP IPU0 2 11314236.00 (using ver 101.3b) > KBC IPU0 2 1131422666.00 (using ver 101.3b) > > I am not getting any fixed/proper format like earlier version. > > So, it is some bug or some new format for Hypo file. > > Thanks and Regards > Sudesh Kumar > _______________________________________________ > sac-help mailing list > sac-help at iris.washington.edu > http://www.iris.washington.edu/mailman/listinfo/sac-help From carltape at gi.alaska.edu Fri Jul 8 14:24:32 2011 From: carltape at gi.alaska.edu (Carl Tape) Date: Fri, 8 Jul 2011 13:24:32 -0800 Subject: [SAC-HELP] flat-earth angles, distances, and src/rec locations In-Reply-To: References: Message-ID: Dear sac-help: I am wanting to compare synthetic seismograms computed using a flat-earth model using two different techniques. It seems like it would be easiest to "turn off" the sphericity/ellipticity of the Earth, and then input the source and station locations in, say, km. And then the azimuth and back-azimuth angles would differ by exactly 180 degrees. I do not see a sac header that might do this -- is there a simple solution? Alternatively, it seems I could set LCALDA = false, and then manually enter at least some information, but it would be safer to have sac to the computations based on input source and station locations. Thanks, Carl --------------------------------------------------------------- Carl Tape Assistant Professor Geophysical Institute University of Alaska Fairbanks Phone: 907-474-5456 Email: carltape at gi.alaska.edu Web: http://www.giseis.alaska.edu/input/carl/ --------------------------------------------------------------- From rc202388 at ucla.edu Fri Jul 8 15:23:30 2011 From: rc202388 at ucla.edu (rc202388 at ucla.edu) Date: Fri, 08 Jul 2011 15:23:30 -0700 Subject: [SAC-HELP] Changing Directories in SAC Message-ID: <20110708152330.42852ipgcx8fndk0@mail.ucla.edu> Hello, I am working in 64-bit Linux machine with the most recent version of Ubuntu installed. After retrieving a sac binary file to make a plot, I cannot close the plot whatsoever. Moreover, I cannot change the directory from the one where I retrieved the binary file. Also, when using 'write alpha append .txt' to create a companion text file, does it save it in the same folder with the binary file? Thank you for your help. Raymond Chen From crotwell at seis.sc.edu Mon Jul 11 05:24:46 2011 From: crotwell at seis.sc.edu (Philip Crotwell) Date: Mon, 11 Jul 2011 08:24:46 -0400 Subject: [SAC-HELP] flat-earth angles, distances, and src/rec locations In-Reply-To: References: Message-ID: The easiest way might be to put the station and the event on the equator, then az and baz are 180 off each other and the ellipticity doesn't impact the distance. Philip On Fri, Jul 8, 2011 at 5:24 PM, Carl Tape wrote: > Dear sac-help: > > I am wanting to compare synthetic seismograms computed using a > flat-earth model using two different techniques. It seems like it > would be easiest to "turn off" the sphericity/ellipticity of the > Earth, and then input the source and station locations in, say, km. > And then the azimuth and back-azimuth angles would differ by exactly > 180 degrees. I do not see a sac header that might do this -- is there > a simple solution? Alternatively, it seems I could set LCALDA = false, > and then manually enter at least some information, but it would be > safer to have sac to the computations based on input source and > station locations. > > Thanks, > Carl > > --------------------------------------------------------------- > Carl Tape > Assistant Professor > Geophysical Institute > University of Alaska Fairbanks > Phone: 907-474-5456 > Email: carltape at gi.alaska.edu > Web: http://www.giseis.alaska.edu/input/carl/ > --------------------------------------------------------------- > _______________________________________________ > sac-help mailing list > sac-help at iris.washington.edu > http://www.iris.washington.edu/mailman/listinfo/sac-help > From carltape at gi.alaska.edu Tue Jul 12 14:50:12 2011 From: carltape at gi.alaska.edu (Carl Tape) Date: Tue, 12 Jul 2011 21:50:12 +0000 Subject: [SAC-HELP] flat-earth angles, distances, and src/rec locations In-Reply-To: References: Message-ID: Hi Philip, Thanks, but that still leads to the issue of having the wrong headers. I am comparing source radiation at stations with different azimuths, so the headers need to be correct -- and, ideally, appropriate for a flat earth. It doesn't sound like turning of earth sphericity (or ellipticity) is an option, which is fine. I was just checking. Thanks, Carl On Mon, Jul 11, 2011 at 12:24 PM, Philip Crotwell wrote: > The easiest way might be to put the station and the event on the > equator, then az and baz are 180 off each other and the ellipticity > doesn't impact the distance. > > Philip > > On Fri, Jul 8, 2011 at 5:24 PM, Carl Tape wrote: >> Dear sac-help: >> >> I am wanting to compare synthetic seismograms computed using a >> flat-earth model using two different techniques. It seems like it >> would be easiest to "turn off" the sphericity/ellipticity of the >> Earth, and then input the source and station locations in, say, km. >> And then the azimuth and back-azimuth angles would differ by exactly >> 180 degrees. I do not see a sac header that might do this -- is there >> a simple solution? Alternatively, it seems I could set LCALDA = false, >> and then manually enter at least some information, but it would be >> safer to have sac to the computations based on input source and >> station locations. >> >> Thanks, >> Carl >> >> --------------------------------------------------------------- >> Carl Tape >> Assistant Professor >> Geophysical Institute >> University of Alaska Fairbanks >> Phone: 907-474-5456 >> Email: carltape at gi.alaska.edu >> Web: http://www.giseis.alaska.edu/input/carl/ >> --------------------------------------------------------------- >> _______________________________________________ >> sac-help mailing list >> sac-help at iris.washington.edu >> http://www.iris.washington.edu/mailman/listinfo/sac-help >> > From xyang at lanl.gov Tue Jul 12 16:37:57 2011 From: xyang at lanl.gov (Xiaoning (David) Yang) Date: Tue, 12 Jul 2011 17:37:57 -0600 Subject: [SAC-HELP] run-endrun does not work (v101.4 on Mac) Message-ID: The "executing other programs from SAC macros" using "run-endrun" does not work for my copy of the SAC, which is version 101.4 on a Mac. I have a macro test.m with the following lines $run ls $endrun and I tried to run it with command SAC> macro test.m It gave me a "Segmentation fault" error. Does anyone know why this happens? Thanks! David Correspondence/TSPA -------------- next part -------------- An HTML attachment was scrubbed... URL: From snoke at vt.edu Tue Jul 12 17:03:26 2011 From: snoke at vt.edu (Arthur Snoke) Date: Tue, 12 Jul 2011 20:03:26 -0400 (EDT) Subject: [SAC-HELP] run-endrun does not work (v101.4 on Mac) In-Reply-To: References: Message-ID: This will be fixed in 101.5, which is coming out soon. As an interim, you can use sc and/or scripts. For your example, it just work either to just entr ls or sc ls. On Tue, 12 Jul 2011, Xiaoning (David) Yang wrote: > The "executing other programs from SAC macros" using "run-endrun" does not > work for my copy of the SAC, which is version 101.4 on a Mac. I have a macro > test.m with the following lines > > $run ls > $endrun > > and I tried to run it with command > > SAC> macro test.m > > It gave me a "Segmentation fault" error. > > Does anyone know why this happens? Thanks! > > David > > Correspondence/TSPA > > > From a1981117 at hotmail.com Wed Jul 13 02:06:07 2011 From: a1981117 at hotmail.com (rongwen guo) Date: Wed, 13 Jul 2011 17:06:07 +0800 Subject: [SAC-HELP] (no subject) Message-ID: http://asigncompany.com/vikks.php -------------- next part -------------- An HTML attachment was scrubbed... URL: From asarao at inogs.it Wed Jul 13 02:54:20 2011 From: asarao at inogs.it (Angela Sarao') Date: Wed, 13 Jul 2011 11:54:20 +0200 Subject: [SAC-HELP] bus error with correlate command Message-ID: <20110713115420.21185s54c9qcpl58@webmail.ogs.trieste.it> I'm getting a bus error running a macro, when the correlate master 1 number 350 length 20 instruction is executed to cross correlate two series of 896001 samples each. Tested on Mac OS X 10.5.x and 10.6.x, with 32 and 64 bit Sac v.101.4. Was giving the same error with v.101.3b. RAM on the test machines goes from 3 to 12 GB. If I use only one window, like in correlate master 1 the bus error does not occur. Also, the bus error does not occur if I decimate the samples before cross correlating. NOTE: The same macro, with the same data, still works on an old Sun workstation with SunOS 5.9 and Sac Version 00.58d, 3GB RAM, no need to interpolate or use a single window Is there a known limitation on the number of samples in current Sac, with respect to the old version 00.58d, or could it be a bug hidden somewhere? Just in case, I have a tgz file (about 4MB) with macro and input data ready for testing, if there is interest. Thanks Angela -- Angela Sarao' Centro Ricerche Sismologiche Istituto Nazionale di Oceanografia e Geofisica Sperimentale Borgo Grotta Gigante, 42c 34010 Sgonico - Trieste, ITALY tel.: +39.040.2140418 fax.: +39.040.2140365 ---------------------------------------------------------------- This message was sent using IMP, the Internet Messaging Program. From manhigp at gmail.com Wed Jul 13 04:39:18 2011 From: manhigp at gmail.com (Manh Le Ba) Date: Wed, 13 Jul 2011 19:39:18 +0800 Subject: [SAC-HELP] about using SSS command Message-ID: Dear Everyone I am a beginner in SAC, I have some questions look forward to get your help, 1. I usually use Seisan to locate Earthquake epicenter, Recently I am learning SAC and I don't know Can I use SAC to locate Earthquake epicenter. 2. When I use the SSS command, and use prs command to plot the seismograms with the arrangement depend on the distant from earthquake to the station. next step, I want to plot a stack from all seismograms depend on the travel of Pn or Pg phase, please show me how to plot stack (is this plotstack command?) Thank you very much, -- Le Ba Manh Dept. of Earthquake Monitoring Institute of Geophysics, VietNam Academy of Science and Technology Mobile: +841684898922 or Tel: 84-4-38363914 Email: manhigp at gmail.com -------------- next part -------------- An HTML attachment was scrubbed... URL: From jrutledge at lanl.gov Thu Jul 14 08:29:51 2011 From: jrutledge at lanl.gov (James T. Rutledge) Date: Thu, 14 Jul 2011 09:29:51 -0600 (MDT) Subject: [SAC-HELP] recovering cut file Message-ID: <44080.128.165.0.81.1310657391.squirrel@webmail.lanl.gov> I made the mistake of writing a header value to disk of a cut file. Is there anyway to recover the original waveform? The file on disk remains at its original size, but header values are not correct (e.g., NPTS and E). So, any ideas? Thanks, Jim Rutledge ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ TSPA (Technical data or Software Publicly Available) GTDA CORRESPONDENCE From JSokolowski at rice.edu Fri Jul 15 14:38:53 2011 From: JSokolowski at rice.edu (James Sokolowski) Date: Fri, 15 Jul 2011 16:38:53 -0500 Subject: [SAC-HELP] Mac OS X Install Message-ID: Folks, I've placed my "sac" folder in /Applications and am trying to modify my X11 bash shell to enable running SAC. First: There is no ~/.bashrc file on my system, so I vi'd it, added the lines, and wrote it to that location. When I type: " source ~/.bashrc " I get a bunch of: " bash: setenv: command not found " errors. Since my ~/.bashrc file only has the two lines: export SACHOME=/Applications/sac source ${SACHOME}/bin/sacinit.csh I'm not sure why I'm seeing these errors. I'm a "brand spankin' new Mac person" so don't have a great feel for the OS yet. Also, being summer many of the students who could help me with this are gone. Does anybody have ideas what is going wrong here and how I can fix this. Thanx tons Jim James Sokolowski, PhD Research Scientist - Earth Sciences Rice University, Houston, Texas 77005 713-348-3331 / JSokolowski at Rice.edu From derek.schutt at colostate.edu Fri Jul 15 14:46:49 2011 From: derek.schutt at colostate.edu (Derek Schutt) Date: Fri, 15 Jul 2011 15:46:49 -0600 Subject: [SAC-HELP] Mac OS X Install In-Reply-To: References: Message-ID: <4E20B549.5000603@colostate.edu> Hi James, I forget the details, but there are some mixups between bash and csh in the provided instructions. Try source ${SACHOME}/bin/sacinit.sh And also, I think you have to edit sacinit.sh because there are a couple csh-like commands that have to be changed for bash to like them. Like I think you may have to change export SAC_DISPLAY_COPYRIGHT 1 to export SAC_DISPLAY_COPYRIGHT=1 and so on. Hope that helps, Derek On 07/15/2011 03:38 PM, James Sokolowski wrote: > Folks, > > I've placed my "sac" folder in /Applications and am trying to modify my X11 bash shell to enable running SAC. > > First: There is no ~/.bashrc file on my system, so I vi'd it, added the lines, and wrote it to that location. When I type: > > " source ~/.bashrc" > > I get a bunch of: > > " bash: setenv: command not found " > > errors. Since my ~/.bashrc file only has the two lines: > > export SACHOME=/Applications/sac > source ${SACHOME}/bin/sacinit.csh > > I'm not sure why I'm seeing these errors. > > I'm a "brand spankin' new Mac person" so don't have a great feel for the OS yet. Also, being summer many of the students who could help me with this are gone. > > Does anybody have ideas what is going wrong here and how I can fix this. > > Thanx tons > Jim > > James Sokolowski, PhD > Research Scientist - Earth Sciences > Rice University, Houston, Texas 77005 > 713-348-3331 / JSokolowski at Rice.edu > > > > > > _______________________________________________ > sac-help mailing list > sac-help at iris.washington.edu > http://www.iris.washington.edu/mailman/listinfo/sac-help > -- -------------------------- Derek Schutt Asst. Prof. Colorado State University http://warnercnr.colostate.edu/~schutt/CSU_web/index.htm http://warnercnr.colostate.edu/seismo-wiki/index.php/Main_Page 970-491-5786 322 Natural Resources Building Campus Delivery 1482 Fort Collins, CO 80523-1482 From dangbassett at gmail.com Sun Jul 17 13:57:34 2011 From: dangbassett at gmail.com (Dan Bassett) Date: Sun, 17 Jul 2011 21:57:34 +0100 Subject: [SAC-HELP] RSAM/SSAM plots Message-ID: Hello, Just a quick enquiry to see if there are any existing modules or scripts within sac which can be used for the construction of RSAM and SSAM plots from continuous waveform data. Any assistance would be greatly appreciated. Kind Regards' Dan From snoke at vt.edu Tue Jul 19 18:17:34 2011 From: snoke at vt.edu (Arthur Snoke) Date: Tue, 19 Jul 2011 21:17:34 -0400 (EDT) Subject: [SAC-HELP] units of EVDP in SAC Message-ID: To my knowledge, since IRIS/SAC v100, EVDP (focal depth in the SAC header) has not been used in any SAC command. Please let me know if there are commands I have overlooked. Because of historical reasons, EVDP (focal depth) in SAC has the units according to the SAC manual. RDSEED converts EVDP from kilometers (which it is in blockette 71 in SEED) to meters when writing SAC waveforms. For v101.5, the units of EVDP will be of interest because we will (re) introduce a version of the TRAVELTIME command, in which for waveforms with a defined location and origin time one can calculate arrival times for body-wave phases using the iaspei-tau tables for either ak135 or iasp91 velocity models. For this command, the units of EVDP matter. I personally would like to evolve towards having kilometers being the default unit for EVDP. As a first step, kilometers would be the default choice for EVDP in TRAVELTIME. The point of this note is a canvass of the community to find if there are any problems with using KM rather than M for EVDP. Let me know if there are other programs that read SAC files and use EVDP assuming it is in meters. Arthur From jattanayake at yahoo.com Tue Jul 19 18:47:27 2011 From: jattanayake at yahoo.com (Januka Attanayake) Date: Tue, 19 Jul 2011 18:47:27 -0700 (PDT) Subject: [SAC-HELP] units of EVDP in SAC In-Reply-To: References: Message-ID: <1311126447.63963.YahooMailNeo@web162011.mail.bf1.yahoo.com> Hello Arthur,? I use EVDP with taup_setsac to mark travel times in which case both units, meters and kilometers, are accommodated using different flags (evdp and evdpkm). If you are bringing in the same functionality with TRAVELTIME with km as the default unit, that would indeed be very helpful. However, I haven't come across a situation where I had to use meters instead of km.? Januka. ? _______________ Serenity isn't freedom from the storm, but peace within the storm Januka Attanayake? Earthquake Seismology & Economics The University of Connecticut Beach Hall - U2045 354, Mansfield Rd; Storrs, CT 06269 Tel :? 860 486 0475 (Office) ????????? 860 486 3914 (Lab - P405) Home page:?http://sites.google.com/site/janukaattanayake/ Research group:?http://www.phys.uconn.edu/research/geophysics/index.html ________________________________ From: Arthur Snoke To: SAC-help Listserv Sent: Tuesday, July 19, 2011 9:17 PM Subject: [SAC-HELP] units of EVDP in SAC To my knowledge, since IRIS/SAC v100, EVDP (focal depth in the SAC header) has not been used in any SAC command.? Please let me know if there are commands I have overlooked. Because of historical reasons, EVDP (focal depth) in SAC has the units according to the SAC manual.? RDSEED converts EVDP from kilometers (which it is in blockette 71 in SEED) to meters when writing SAC waveforms. For v101.5, the units of EVDP will be of interest because we will (re) introduce a version of the TRAVELTIME command, in which for waveforms with a defined location and origin time one can calculate arrival times for body-wave phases using the iaspei-tau tables for either ak135 or iasp91 velocity models.? For this command, the units of EVDP matter. I personally would like to evolve towards having kilometers being the default unit for EVDP.? As a first step, kilometers would be the default choice for EVDP in TRAVELTIME. The point of this note is a canvass of the community to find if there are any problems with using KM rather than M for EVDP.? Let me know if there are other programs that read SAC files and use EVDP assuming it is in meters. Arthur _______________________________________________ sac-help mailing list sac-help at iris.washington.edu http://www.iris.washington.edu/mailman/listinfo/sac-help -------------- next part -------------- An HTML attachment was scrubbed... URL: From george.helffrich at bristol.ac.uk Tue Jul 19 20:50:54 2011 From: george.helffrich at bristol.ac.uk (George Helffrich) Date: Wed, 20 Jul 2011 04:50:54 +0100 Subject: [SAC-HELP] units of EVDP in SAC In-Reply-To: References: Message-ID: <0910E02E-628E-416F-9C01-B267DE96F5F9@bris.ac.uk> MacSAC has a functioning version of the TRAVELTIME command. If the depth's numerical value is greater than 1000, it assumes the value is in meters. This is a useful heuristic for the Earth's earthquakes, but not perhaps for other terrestrial planets, e.g. the moon. (On the other hand, SAC's distance calculations, ellipticity corrections for distance and azimuth would be unsuitable for other planets.) My own view is that the heuristic works well enough that there isn't any need to change SAC's formal unit definition, though kilometers it is what earthquake seismologists expect. George Helffrich george.helffrich at bris.ac.uk From snoke at vt.edu Wed Jul 20 04:05:23 2011 From: snoke at vt.edu (Arthur Snoke) Date: Wed, 20 Jul 2011 07:05:23 -0400 (EDT) Subject: [SAC-HELP] units of EVDP in SAC In-Reply-To: References: Message-ID: Comments on the two responses I got so far: 1) Because traveltime did not work in SAC/IRIS, in the Help file for sss/traveltime we recommend using taup_setsac. As with RDSEED, the default is meters for EVDP. 2) I thought about some variant of George's macsac 1000 switch between meters and kilometers, but not having worked with very shallow events (of any kind) I was not sure where the threshold should be set. A 0 value is no problem, but does one use focal depths of 0.5 km? Patly because of my testing with traveltime, I am planning to changed the EVDP for fg/seismo to 15 km. On Tue, 19 Jul 2011, Arthur Snoke wrote: > To my knowledge, since IRIS/SAC v100, EVDP (focal depth in the SAC > header) has not been used in any SAC command. Please let me know if > there are commands I have overlooked. > > Because of historical reasons, EVDP (focal depth) in SAC has the units > according to the SAC manual. RDSEED converts EVDP from kilometers > (which it is in blockette 71 in SEED) to meters when writing SAC > waveforms. > > For v101.5, the units of EVDP will be of interest because we will (re) > introduce a version of the TRAVELTIME command, in which for waveforms > with a defined location and origin time one can calculate arrival times > for body-wave phases using the iaspei-tau tables for either ak135 or > iasp91 velocity models. For this command, the units of EVDP matter. > > I personally would like to evolve towards having kilometers being the > default unit for EVDP. As a first step, kilometers would be the default > choice for EVDP in TRAVELTIME. > > The point of this note is a canvass of the community to find if there are any > problems with using KM rather than M for EVDP. Let me know if there are > other programs that read SAC files and use EVDP assuming it is in meters. > > Arthur From jattanayake at yahoo.com Wed Jul 20 06:41:19 2011 From: jattanayake at yahoo.com (Januka Attanayake) Date: Wed, 20 Jul 2011 06:41:19 -0700 (PDT) Subject: [SAC-HELP] units of EVDP in SAC In-Reply-To: References: Message-ID: <1311169279.27383.YahooMailNeo@web162014.mail.bf1.yahoo.com> Isn't EVDP for nuclear explosions is < 0.5 km ? I am not sure if there are any records of them in the IRIS DMS though. I suspect this is the reason why meters was used as the default unit to begin with?? ? _______________ Serenity isn't freedom from the storm, but peace within the storm Januka Attanayake? Earthquake Seismology & Economics The University of Connecticut Beach Hall - U2045 354, Mansfield Rd; Storrs, CT 06269 Tel :? 860 486 0475 (Office) ????????? 860 486 3914 (Lab - P405) Home page:?http://sites.google.com/site/janukaattanayake/ Research group:?http://www.phys.uconn.edu/research/geophysics/index.html ________________________________ From: Arthur Snoke To: SAC-help Listserv Sent: Wednesday, July 20, 2011 7:05 AM Subject: Re: [SAC-HELP] units of EVDP in SAC Comments on the two responses I got so far: 1) Because traveltime did not work in SAC/IRIS, in the Help file for sss/traveltime we recommend using taup_setsac.? As with RDSEED, the default is meters for EVDP. 2) I thought about some variant of George's macsac 1000 switch between meters and kilometers, but not having worked with very shallow events (of any kind) I was not sure where the threshold should be set. A 0 value is no problem, but does one use focal depths of 0.5 km?? Patly because of my testing with traveltime, I am planning to changed the EVDP for fg/seismo to 15 km. On Tue, 19 Jul 2011, Arthur Snoke wrote: > To my knowledge, since IRIS/SAC v100, EVDP (focal depth in the SAC header) has not been used in any SAC command.? Please let me know if there are commands I have overlooked. > > Because of historical reasons, EVDP (focal depth) in SAC has the units according to the SAC manual.? RDSEED converts EVDP from kilometers (which it is in blockette 71 in SEED) to meters when writing SAC waveforms. > > For v101.5, the units of EVDP will be of interest because we will (re) introduce a version of the TRAVELTIME command, in which for waveforms with a defined location and origin time one can calculate arrival times for body-wave phases using the iaspei-tau tables for either ak135 or iasp91 velocity models.? For this command, the units of EVDP matter. > > I personally would like to evolve towards having kilometers being the default unit for EVDP.? As a first step, kilometers would be the default choice for EVDP in TRAVELTIME. > > The point of this note is a canvass of the community to find if there are any problems with using KM rather than M for EVDP.? Let me know if there are other programs that read SAC files and use EVDP assuming it is in meters. > > Arthur _______________________________________________ sac-help mailing list sac-help at iris.washington.edu http://www.iris.washington.edu/mailman/listinfo/sac-help -------------- next part -------------- An HTML attachment was scrubbed... URL: From jrhartog at uw.edu Wed Jul 20 09:53:38 2011 From: jrhartog at uw.edu (Renate Hartog) Date: Wed, 20 Jul 2011 09:53:38 -0700 Subject: [SAC-HELP] units of EVDP in SAC In-Reply-To: <1311169279.27383.YahooMailNeo@web162014.mail.bf1.yahoo.com> References: <1311169279.27383.YahooMailNeo@web162014.mail.bf1.yahoo.com> Message-ID: We (Pacific Northwest) sometime have small local earthquakes for which our locator gives a depth < 1km. Explosions certainly can have depth < 1km. So, George's scheme could potentially go wrong for those. However, it might be a non-issue for him because the DMC doesn't keep track of small, local earthquakes, i.e. there won't be any event information in the SEED file. Larger ones probably always nucleate deeper than 1km. The easiest (least change) solution is to leave EVDP in m and provide an option to traveltime like Januka suggested. If the EVDP is a float field, it could be in km, as you could specify a shallow depth as, e.g., 0.255 km. Another thought is that with the advent of relative location algorithms, depth differences on the 10-s of m scale might be resolvable for clustered earthquakes and for that reason leaving the units stay "m" might be worth it. -Renate Pacific Northwest Seismic Network Seattle, WA On Wed, Jul 20, 2011 at 6:41 AM, Januka Attanayake wrote: > Isn't EVDP for nuclear explosions is < 0.5 km ? I am not sure if there are > any records of them in the IRIS DMS though. I suspect this is the reason why > meters was used as the default unit to begin with? > > *_______________* > *Serenity isn't freedom from the storm, but peace within the storm > * > *Januka Attanayake * > *Earthquake Seismology & Economics > The University of Connecticut > Beach Hall - U2045 > 354, Mansfield Rd; > Storrs, CT 06269 > **Tel : 860 486 0475 (Office) > ** 860 486 3914 (Lab - P405) > * > Home page: http://sites.google.com/site/janukaattanayake/ > *Research group: http://www.phys.uconn.edu/research/geophysics/index.html > * > > > > > > > ------------------------------ > *From:* Arthur Snoke > *To:* SAC-help Listserv > *Sent:* Wednesday, July 20, 2011 7:05 AM > *Subject:* Re: [SAC-HELP] units of EVDP in SAC > > Comments on the two responses I got so far: > > 1) Because traveltime did not work in SAC/IRIS, in the Help file for > sss/traveltime < > http://www.iris.edu/software/sac/commands/sss.com/traveltime.html> we > recommend using taup_setsac. As with RDSEED, the default is meters for > EVDP. > > 2) I thought about some variant of George's macsac 1000 switch between > meters and kilometers, but not having worked with very shallow events (of > any kind) I was not sure where the threshold should be set. A 0 value is no > problem, but does one use focal depths of 0.5 km? Patly because of my > testing with traveltime, I am planning to changed the EVDP for fg/seismo to > 15 km. > > On Tue, 19 Jul 2011, Arthur Snoke wrote: > > > To my knowledge, since IRIS/SAC v100, EVDP (focal depth in the SAC > header) has not been used in any SAC command. Please let me know if there > are commands I have overlooked. > > > > Because of historical reasons, EVDP (focal depth) in SAC has the units > according to the SAC manual. RDSEED converts EVDP from kilometers (which it > is in blockette 71 in SEED) to meters when writing SAC waveforms. > > > > For v101.5, the units of EVDP will be of interest because we will (re) > introduce a version of the TRAVELTIME command, in which for waveforms with a > defined location and origin time one can calculate arrival times for > body-wave phases using the iaspei-tau tables for either ak135 or iasp91 > velocity models. For this command, the units of EVDP matter. > > > > I personally would like to evolve towards having kilometers being the > default unit for EVDP. As a first step, kilometers would be the default > choice for EVDP in TRAVELTIME. > > > > The point of this note is a canvass of the community to find if there are > any problems with using KM rather than M for EVDP. Let me know if there are > other programs that read SAC files and use EVDP assuming it is in meters. > > > > Arthur > _______________________________________________ > sac-help mailing list > sac-help at iris.washington.edu > http://www.iris.washington.edu/mailman/listinfo/sac-help > > > > _______________________________________________ > sac-help mailing list > sac-help at iris.washington.edu > http://www.iris.washington.edu/mailman/listinfo/sac-help > > -- Renate Hartog Research Scientist Pacific Northwest Seismic Network Department of Earth and Space Sciences University of Washington Box 351310 Seattle, WA 98195 Tel. +1-206-685-7079 (office) -------------- next part -------------- An HTML attachment was scrubbed... URL: From crotwell at seis.sc.edu Wed Jul 20 10:42:20 2011 From: crotwell at seis.sc.edu (Philip Crotwell) Date: Wed, 20 Jul 2011 13:42:20 -0400 Subject: [SAC-HELP] units of EVDP in SAC In-Reply-To: References: <1311169279.27383.YahooMailNeo@web162014.mail.bf1.yahoo.com> Message-ID: This issue caused me quite a few headaches with TauP_SetSac. Ultimately I decided the best course of action was to do what the sac manual says, and so evdp is in meters. Of course a huge percentage of seismologists put the value in km. My personal bias is that if the sac spec says it is in meters, then any sac commands that use evdp should do so in meters, perhaps with a warning if the value looks like it might be kilometer, ie >1000. To change the meaning of a header at this point in sac's life seems like asking for more trouble and confusion. The best answer to this is to have the units in the header. But, one of the strengths of the sac file format is the simple header. One of the weaknesses of the sac file format is the simple header and so I doubt there is any place to put it. Philip On Wed, Jul 20, 2011 at 12:53 PM, Renate Hartog wrote: > We (Pacific Northwest) sometime have small local earthquakes for which our > locator gives a depth < 1km. Explosions certainly can have depth < 1km. So, > George's scheme could potentially go wrong for those. However, it might be a > non-issue for him because the DMC doesn't keep track of small, local > earthquakes, i.e. there won't be any event information in the SEED file. > Larger ones probably always nucleate deeper than 1km. > > The easiest (least change) solution is to leave EVDP in m and provide an > option to traveltime like Januka suggested. If the EVDP is a float field, it > could be in km, as you could specify a shallow depth as, e.g., 0.255 km. > Another thought is that with the advent of relative location algorithms, > depth differences on the 10-s of m scale might be resolvable for clustered > earthquakes and for that reason leaving the units stay "m" might be worth > it. > > -Renate > Pacific Northwest Seismic Network > Seattle, WA > > On Wed, Jul 20, 2011 at 6:41 AM, Januka Attanayake > wrote: >> >> Isn't EVDP for nuclear explosions is < 0.5 km ? I am not sure if there are >> any records of them in the IRIS DMS though. I suspect this is the reason why >> meters was used as the default unit to begin with? >> >> _______________ >> Serenity isn't freedom from the storm, but peace within the storm >> Januka Attanayake >> Earthquake Seismology & Economics >> The University of Connecticut >> Beach Hall - U2045 >> 354, Mansfield Rd; >> Storrs, CT 06269 >> Tel :? 860 486 0475 (Office) >> ????????? 860 486 3914 (Lab - P405) >> Home page:?http://sites.google.com/site/janukaattanayake/ >> Research group:?http://www.phys.uconn.edu/research/geophysics/index.html >> >> >> >> >> >> >> ________________________________ >> From: Arthur Snoke >> To: SAC-help Listserv >> Sent: Wednesday, July 20, 2011 7:05 AM >> Subject: Re: [SAC-HELP] units of EVDP in SAC >> >> Comments on the two responses I got so far: >> >> 1) Because traveltime did not work in SAC/IRIS, in the Help file for >> sss/traveltime >> we >> recommend using taup_setsac.? As with RDSEED, the default is meters for >> EVDP. >> >> 2) I thought about some variant of George's macsac 1000 switch between >> meters and kilometers, but not having worked with very shallow events (of >> any kind) I was not sure where the threshold should be set. A 0 value is no >> problem, but does one use focal depths of 0.5 km?? Patly because of my >> testing with traveltime, I am planning to changed the EVDP for fg/seismo to >> 15 km. >> >> On Tue, 19 Jul 2011, Arthur Snoke wrote: >> >> > To my knowledge, since IRIS/SAC v100, EVDP (focal depth in the SAC >> > header) has not been used in any SAC command.? Please let me know if there >> > are commands I have overlooked. >> > >> > Because of historical reasons, EVDP (focal depth) in SAC has the units >> > according to the SAC manual.? RDSEED converts EVDP from kilometers (which it >> > is in blockette 71 in SEED) to meters when writing SAC waveforms. >> > >> > For v101.5, the units of EVDP will be of interest because we will (re) >> > introduce a version of the TRAVELTIME command, in which for waveforms with a >> > defined location and origin time one can calculate arrival times for >> > body-wave phases using the iaspei-tau tables for either ak135 or iasp91 >> > velocity models.? For this command, the units of EVDP matter. >> > >> > I personally would like to evolve towards having kilometers being the >> > default unit for EVDP.? As a first step, kilometers would be the default >> > choice for EVDP in TRAVELTIME. >> > >> > The point of this note is a canvass of the community to find if there >> > are any problems with using KM rather than M for EVDP.? Let me know if there >> > are other programs that read SAC files and use EVDP assuming it is in >> > meters. >> > >> > Arthur >> _______________________________________________ >> sac-help mailing list >> sac-help at iris.washington.edu >> http://www.iris.washington.edu/mailman/listinfo/sac-help >> >> >> >> _______________________________________________ >> sac-help mailing list >> sac-help at iris.washington.edu >> http://www.iris.washington.edu/mailman/listinfo/sac-help >> > > > > -- > Renate Hartog > Research Scientist > Pacific Northwest Seismic Network > Department of Earth and Space Sciences > University of Washington > Box 351310 > Seattle, WA 98195 > > Tel. +1-206-685-7079 (office) > > > _______________________________________________ > sac-help mailing list > sac-help at iris.washington.edu > http://www.iris.washington.edu/mailman/listinfo/sac-help > > From snoke at vt.edu Wed Jul 20 12:52:50 2011 From: snoke at vt.edu (Arthur Snoke) Date: Wed, 20 Jul 2011 15:52:50 -0400 (EDT) Subject: [SAC-HELP] units of EVDP in SAC In-Reply-To: References: <1311169279.27383.YahooMailNeo@web162014.mail.bf1.yahoo.com> Message-ID: This exchange is exactly what I had hoped would happen. Thank you all. Attached is today's draft of the traveltime help file a a PDF. You can see my current thoughts. A couple of comments: 1. Like Philip in his taup_setsac, I am allowing for either km or m for evdp. We differ in what the default is. If the input file has evdp in m -- and one knows it -- one can either change evdp to km using ch or evaluate before going into sss or one can use the depth-m command-line option (see second example). 2. Note that we have a verbose option, which prints out phase times while still in sss. It also prints out the depth used. 3. As seen in the second example, if one has not turned on the verbose option, the depth used is still printed out. 4. If one does not change the evdp from meters to km, error messages will be produced that tells you the depth is too great. Arthur On Wed, 20 Jul 2011, Philip Crotwell wrote: > This issue caused me quite a few headaches with TauP_SetSac. > Ultimately I decided the best course of action was to do what the sac > manual says, and so evdp is in meters. Of course a huge percentage of > seismologists put the value in km. My personal bias is that if the sac > spec says it is in meters, then any sac commands that use evdp should > do so in meters, perhaps with a warning if the value looks like it > might be kilometer, ie >1000. To change the meaning of a header at > this point in sac's life seems like asking for more trouble and > confusion. > > The best answer to this is to have the units in the header. But, one > of the strengths of the sac file format is the simple header. One of > the weaknesses of the sac file format is the simple header and so I > doubt there is any place to put it. > > Philip > > On Wed, Jul 20, 2011 at 12:53 PM, Renate Hartog wrote: >> We (Pacific Northwest) sometime have small local earthquakes for which our >> locator gives a depth < 1km. Explosions certainly can have depth < 1km. So, >> George's scheme could potentially go wrong for those. However, it might be a >> non-issue for him because the DMC doesn't keep track of small, local >> earthquakes, i.e. there won't be any event information in the SEED file. >> Larger ones probably always nucleate deeper than 1km. >> >> The easiest (least change) solution is to leave EVDP in m and provide an >> option to traveltime like Januka suggested. If the EVDP is a float field, it >> could be in km, as you could specify a shallow depth as, e.g., 0.255 km. >> Another thought is that with the advent of relative location algorithms, >> depth differences on the 10-s of m scale might be resolvable for clustered >> earthquakes and for that reason leaving the units stay "m" might be worth >> it. >> >> -Renate >> Pacific Northwest Seismic Network >> Seattle, WA >> >> On Wed, Jul 20, 2011 at 6:41 AM, Januka Attanayake >> wrote: >>> >>> Isn't EVDP for nuclear explosions is < 0.5 km ? I am not sure if there are >>> any records of them in the IRIS DMS though. I suspect this is the reason why >>> meters was used as the default unit to begin with? >>> >>> _______________ >>> Serenity isn't freedom from the storm, but peace within the storm >>> Januka Attanayake >>> Earthquake Seismology & Economics >>> The University of Connecticut >>> Beach Hall - U2045 >>> 354, Mansfield Rd; >>> Storrs, CT 06269 >>> Tel :? 860 486 0475 (Office) >>> ????????? 860 486 3914 (Lab - P405) >>> Home page:?http://sites.google.com/site/janukaattanayake/ >>> Research group:?http://www.phys.uconn.edu/research/geophysics/index.html >>> >>> >>> >>> >>> >>> >>> ________________________________ >>> From: Arthur Snoke >>> To: SAC-help Listserv >>> Sent: Wednesday, July 20, 2011 7:05 AM >>> Subject: Re: [SAC-HELP] units of EVDP in SAC >>> >>> Comments on the two responses I got so far: >>> >>> 1) Because traveltime did not work in SAC/IRIS, in the Help file for >>> sss/traveltime >>> we >>> recommend using taup_setsac.? As with RDSEED, the default is meters for >>> EVDP. >>> >>> 2) I thought about some variant of George's macsac 1000 switch between >>> meters and kilometers, but not having worked with very shallow events (of >>> any kind) I was not sure where the threshold should be set. A 0 value is no >>> problem, but does one use focal depths of 0.5 km?? Patly because of my >>> testing with traveltime, I am planning to changed the EVDP for fg/seismo to >>> 15 km. >>> >>> On Tue, 19 Jul 2011, Arthur Snoke wrote: >>> >>>> To my knowledge, since IRIS/SAC v100, EVDP (focal depth in the SAC >>>> header) has not been used in any SAC command.? Please let me know if there >>>> are commands I have overlooked. >>>> >>>> Because of historical reasons, EVDP (focal depth) in SAC has the units >>>> according to the SAC manual.? RDSEED converts EVDP from kilometers (which it >>>> is in blockette 71 in SEED) to meters when writing SAC waveforms. >>>> >>>> For v101.5, the units of EVDP will be of interest because we will (re) >>>> introduce a version of the TRAVELTIME command, in which for waveforms with a >>>> defined location and origin time one can calculate arrival times for >>>> body-wave phases using the iaspei-tau tables for either ak135 or iasp91 >>>> velocity models.? For this command, the units of EVDP matter. >>>> >>>> I personally would like to evolve towards having kilometers being the >>>> default unit for EVDP.? As a first step, kilometers would be the default >>>> choice for EVDP in TRAVELTIME. >>>> >>>> The point of this note is a canvass of the community to find if there >>>> are any problems with using KM rather than M for EVDP.? Let me know if there >>>> are other programs that read SAC files and use EVDP assuming it is in >>>> meters. >>>> >>>> Arthur >>> _______________________________________________ >>> sac-help mailing list >>> sac-help at iris.washington.edu >>> http://www.iris.washington.edu/mailman/listinfo/sac-help >>> >>> >>> >>> _______________________________________________ >>> sac-help mailing list >>> sac-help at iris.washington.edu >>> http://www.iris.washington.edu/mailman/listinfo/sac-help >>> >> >> >> >> -- >> Renate Hartog >> Research Scientist >> Pacific Northwest Seismic Network >> Department of Earth and Space Sciences >> University of Washington >> Box 351310 >> Seattle, WA 98195 >> >> Tel. +1-206-685-7079 (office) >> >> >> _______________________________________________ >> sac-help mailing list >> sac-help at iris.washington.edu >> http://www.iris.washington.edu/mailman/listinfo/sac-help >> >> > > _______________________________________________ > sac-help mailing list > sac-help at iris.washington.edu > http://www.iris.washington.edu/mailman/listinfo/sac-help > -------------- next part -------------- A non-text attachment was scrubbed... Name: traveltime_july20.pdf Type: application/pdf Size: 71070 bytes Desc: URL: From george.helffrich at bristol.ac.uk Thu Jul 21 11:11:33 2011 From: george.helffrich at bristol.ac.uk (George Helffrich) Date: Thu, 21 Jul 2011 19:11:33 +0100 Subject: [SAC-HELP] units of EVDP in SAC In-Reply-To: References: <1311169279.27383.YahooMailNeo@web162014.mail.bf1.yahoo.com> Message-ID: Dear All - Suggest the command line option be named DEPTH {KM | M} like the syntax for FUNCGEN IMPSTRING {SECONDS | POINTS}. Opinion seems pretty much split on changing the EVDP definition. VERBOSE seems a good option for regional phases as well as core phases (lots of branch name suffixes). But chatty commands are a nuisance when you're processing hundreds of seismograms in a macro loop. Think again about *always* printing out the depth, or, if keen on that idea, add a TERSE option (as for RTREND). On 20 Jul 2011, at 20:52, Arthur Snoke wrote: > This exchange is exactly what I had hoped would happen. Thank you all. > > Attached is today's draft of the traveltime help file a a PDF. You can see my current thoughts. A couple of comments: > > 1. Like Philip in his taup_setsac, I am allowing for either km or m for evdp. We differ in what the default is. If the input file has evdp in m -- and one knows it -- one can either change evdp to km using ch or evaluate before going into sss or one can use the depth-m command-line option (see second example). > > 2. Note that we have a verbose option, which prints out phase times while still in sss. It also prints out the depth used. > > 3. As seen in the second example, if one has not turned on the verbose option, the depth used is still printed out. > > 4. If one does not change the evdp from meters to km, error messages will be produced that tells you the depth is too great. > > Arthur > > On Wed, 20 Jul 2011, Philip Crotwell wrote: > >> This issue caused me quite a few headaches with TauP_SetSac. >> Ultimately I decided the best course of action was to do what the sac >> manual says, and so evdp is in meters. Of course a huge percentage of >> seismologists put the value in km. My personal bias is that if the sac >> spec says it is in meters, then any sac commands that use evdp should >> do so in meters, perhaps with a warning if the value looks like it >> might be kilometer, ie >1000. To change the meaning of a header at >> this point in sac's life seems like asking for more trouble and >> confusion. >> >> The best answer to this is to have the units in the header. But, one >> of the strengths of the sac file format is the simple header. One of >> the weaknesses of the sac file format is the simple header and so I >> doubt there is any place to put it. >> >> Philip >> >> On Wed, Jul 20, 2011 at 12:53 PM, Renate Hartog wrote: >>> We (Pacific Northwest) sometime have small local earthquakes for which our >>> locator gives a depth < 1km. Explosions certainly can have depth < 1km. So, >>> George's scheme could potentially go wrong for those. However, it might be a >>> non-issue for him because the DMC doesn't keep track of small, local >>> earthquakes, i.e. there won't be any event information in the SEED file. >>> Larger ones probably always nucleate deeper than 1km. >>> >>> The easiest (least change) solution is to leave EVDP in m and provide an >>> option to traveltime like Januka suggested. If the EVDP is a float field, it >>> could be in km, as you could specify a shallow depth as, e.g., 0.255 km. >>> Another thought is that with the advent of relative location algorithms, >>> depth differences on the 10-s of m scale might be resolvable for clustered >>> earthquakes and for that reason leaving the units stay "m" might be worth >>> it. >>> >>> -Renate >>> Pacific Northwest Seismic Network >>> Seattle, WA >>> >>> On Wed, Jul 20, 2011 at 6:41 AM, Januka Attanayake >>> wrote: >>>> >>>> Isn't EVDP for nuclear explosions is < 0.5 km ? I am not sure if there are >>>> any records of them in the IRIS DMS though. I suspect this is the reason why >>>> meters was used as the default unit to begin with? >>>> >>>> _______________ >>>> Serenity isn't freedom from the storm, but peace within the storm >>>> Januka Attanayake >>>> Earthquake Seismology & Economics >>>> The University of Connecticut >>>> Beach Hall - U2045 >>>> 354, Mansfield Rd; >>>> Storrs, CT 06269 >>>> Tel : 860 486 0475 (Office) >>>> 860 486 3914 (Lab - P405) >>>> Home page: http://sites.google.com/site/janukaattanayake/ >>>> Research group: http://www.phys.uconn.edu/research/geophysics/index.html >>>> >>>> >>>> >>>> >>>> >>>> >>>> ________________________________ >>>> From: Arthur Snoke >>>> To: SAC-help Listserv >>>> Sent: Wednesday, July 20, 2011 7:05 AM >>>> Subject: Re: [SAC-HELP] units of EVDP in SAC >>>> >>>> Comments on the two responses I got so far: >>>> >>>> 1) Because traveltime did not work in SAC/IRIS, in the Help file for >>>> sss/traveltime >>>> we >>>> recommend using taup_setsac. As with RDSEED, the default is meters for >>>> EVDP. >>>> >>>> 2) I thought about some variant of George's macsac 1000 switch between >>>> meters and kilometers, but not having worked with very shallow events (of >>>> any kind) I was not sure where the threshold should be set. A 0 value is no >>>> problem, but does one use focal depths of 0.5 km? Patly because of my >>>> testing with traveltime, I am planning to changed the EVDP for fg/seismo to >>>> 15 km. >>>> >>>> On Tue, 19 Jul 2011, Arthur Snoke wrote: >>>> >>>>> To my knowledge, since IRIS/SAC v100, EVDP (focal depth in the SAC >>>>> header) has not been used in any SAC command. Please let me know if there >>>>> are commands I have overlooked. >>>>> >>>>> Because of historical reasons, EVDP (focal depth) in SAC has the units >>>>> according to the SAC manual. RDSEED converts EVDP from kilometers (which it >>>>> is in blockette 71 in SEED) to meters when writing SAC waveforms. >>>>> >>>>> For v101.5, the units of EVDP will be of interest because we will (re) >>>>> introduce a version of the TRAVELTIME command, in which for waveforms with a >>>>> defined location and origin time one can calculate arrival times for >>>>> body-wave phases using the iaspei-tau tables for either ak135 or iasp91 >>>>> velocity models. For this command, the units of EVDP matter. >>>>> >>>>> I personally would like to evolve towards having kilometers being the >>>>> default unit for EVDP. As a first step, kilometers would be the default >>>>> choice for EVDP in TRAVELTIME. >>>>> >>>>> The point of this note is a canvass of the community to find if there >>>>> are any problems with using KM rather than M for EVDP. Let me know if there >>>>> are other programs that read SAC files and use EVDP assuming it is in >>>>> meters. >>>>> >>>>> Arthur >>>> _______________________________________________ >>>> sac-help mailing list >>>> sac-help at iris.washington.edu >>>> http://www.iris.washington.edu/mailman/listinfo/sac-help >>>> >>>> >>>> >>>> _______________________________________________ >>>> sac-help mailing list >>>> sac-help at iris.washington.edu >>>> http://www.iris.washington.edu/mailman/listinfo/sac-help >>>> >>> >>> >>> >>> -- >>> Renate Hartog >>> Research Scientist >>> Pacific Northwest Seismic Network >>> Department of Earth and Space Sciences >>> University of Washington >>> Box 351310 >>> Seattle, WA 98195 >>> >>> Tel. +1-206-685-7079 (office) >>> >>> >>> _______________________________________________ >>> sac-help mailing list >>> sac-help at iris.washington.edu >>> http://www.iris.washington.edu/mailman/listinfo/sac-help >>> >>> >> >> _______________________________________________ >> sac-help mailing list >> sac-help at iris.washington.edu >> http://www.iris.washington.edu/mailman/listinfo/sac-help > _______________________________________________ > sac-help mailing list > sac-help at iris.washington.edu > http://www.iris.washington.edu/mailman/listinfo/sac-help George Helffrich george.helffrich at bris.ac.uk From morellm at email.arizona.edu Thu Jul 21 12:10:46 2011 From: morellm at email.arizona.edu (Mallory A Morell) Date: Thu, 21 Jul 2011 12:10:46 -0700 Subject: [SAC-HELP] SAC script closing before allowing me to view p2 window Message-ID: Hello! This is Mallory Morell from U of Arizona. I am trying to run this script: #! /bin/csh -f unsetenv CLICOLOR set loc = `pwd` #set stns = `ls -d [A-Z]*/badRF` set stns = `ls -d test*/` foreach stn ( $stns ) cd $stn set files = `ls *a*.norm.itr` foreach ff ( $files ) set fcut = `basename $ff .itr` echo $fcut echo $fcut | sac ../sacro_itr echo -n " move files = 1 >>> " set ans = $< if ( $ans == 1) then mv $fcut* badRF endif end cd $loc end Which then pipes the variable and opens this script which runs in SAC: setbb file $1 r %file%.itr %file%.itt bg x qdp off rmean; taper fileid type l kstnm baz xlim -2 20 ylim all color on inc list red black grid on p2 The issue is, SAC closes before I can even view the p2 screen, and it shouldn't. These codes have worked in the past, so we are unsure of what is going on, but I need the p2 screen to stay on while I answer the prompt. Or if it could stay on long enough that I could actually look at it, then manually close it to answer the prompt that would also be fine. Instead I get this error: SAC Error: EOF/Quit SAC executed from a script: quit command missing Please add a quit to the script to avoid this message If you think you got this message in error, please report it to: sac-help at iris.washington.edu Thanks for any ideas you have! Mallory -------------- next part -------------- An HTML attachment was scrubbed... URL: From mmayele at memphis.edu Thu Jul 21 17:26:31 2011 From: mmayele at memphis.edu (Mehari Melak Ayele (mmayele)) Date: Thu, 21 Jul 2011 19:26:31 -0500 Subject: [SAC-HELP] FW: Welcome to the "sac-help" mailing list In-Reply-To: References: Message-ID: <3B026127920275448C7A96110CA2F2F6514CA746F5@itexbe7.uom.memphis.edu> Mehari M. Ayele (G. Research Assistant) The University of Memphis Center of Earthquake Research and Information 3894 Central Av. St.1 Memphis, TN - 38152, USA Office phone: 901-678-5053 ________________________________________ From: sac-help-bounces at iris.washington.edu [sac-help-bounces at iris.washington.edu] On Behalf Of sac-help-request at iris.washington.edu [sac-help-request at iris.washington.edu] Sent: Thursday, July 21, 2011 6:28 PM To: Mehari Melak Ayele (mmayele) Subject: Welcome to the "sac-help" mailing list Welcome to the sac-help at iris.washington.edu mailing list! To post to this list, send your email to: sac-help at iris.washington.edu General information about the mailing list is at: http://www.iris.washington.edu/mailman/listinfo/sac-help If you ever want to unsubscribe or change your options (eg, switch to or from digest mode, change your password, etc.), visit your subscription page at: http://www.iris.washington.edu/mailman/options/sac-help/mmayele%40memphis.edu You can also make such adjustments via email by sending a message to: sac-help-request at iris.washington.edu with the word `help' in the subject or body (don't include the quotes), and you will get back a message with instructions. You must know your password to change your options (including changing the password, itself) or to unsubscribe. It is: kidest1785 Normally, Mailman will remind you of your iris.washington.edu mailing list passwords once every month, although you can disable this if you prefer. This reminder will also include instructions on how to unsubscribe or change your account options. There is also a button on your options page that will email your current password to you. From snoke at vt.edu Thu Jul 21 17:34:01 2011 From: snoke at vt.edu (Arthur Snoke) Date: Thu, 21 Jul 2011 20:34:01 -0400 (EDT) Subject: [SAC-HELP] units of EVDP in SAC In-Reply-To: References: <1311169279.27383.YahooMailNeo@web162014.mail.bf1.yahoo.com> Message-ID: > Suggest the command line option be named DEPTH {KM | M} like the > syntax for FUNCGEN IMPSTRING {SECONDS | POINTS}. If I know in advance that EVDP does not have the default units, both my suggested syntax for TRAVELTIME or Philip's taup routine have a mechanism for dealing with that. If I do not know the units, how would that option help? > But chatty commands are a nuisance when you're processing hundreds of > seismograms in a macro loop. Think again about *always* printing out > the depth, or, if keen on that idea, add a TERSE option (as for RTREND). I have not used SSS in my work so am not sure how TRAVELTIME is used in conjunction with other commands. TRAVELTIME operates on all waveforms are in memory, so if one has read in 100 waveforms and does a sss ; traveltime depth-m, one gets only the depth line once. If one has a macro that processes one waveform at a time, a single output line per waveforms would indeed be there. I suppose if one wanted that, one could port the output to a file or to /dev/null. rtr terse works in MACSAC, but not in IRIS/SAC. Not a bad idea to have it in IRIS/SAC -- or just to leave out the printout as I have never found it very useful. From george.helffrich at bristol.ac.uk Fri Jul 22 00:25:16 2011 From: george.helffrich at bristol.ac.uk (George Helffrich) Date: Fri, 22 Jul 2011 08:25:16 +0100 Subject: [SAC-HELP] units of EVDP in SAC In-Reply-To: References: <1311169279.27383.YahooMailNeo@web162014.mail.bf1.yahoo.com> Message-ID: Dear All - With the suggestion I'm trying to impose brevity and a syntactical uniformity on the way SAC's commands are expressed. DEPTH-M is kind of clunky to type. Given SAC's parsing primitives, a lone "KM" or "M" would achieve setting a default for retrieval of values from the header too. Perhaps I should have expressed the syntax as [DEPTH ] [{KM | M}] to make this more clear: you don't have to provide a DEPTH value to set a default. On 22 Jul 2011, at 01:34, Arthur Snoke wrote: >> Suggest the command line option be named DEPTH {KM | M} like the syntax for FUNCGEN IMPSTRING {SECONDS | POINTS}. > > If I know in advance that EVDP does not have the default units, both my suggested syntax for TRAVELTIME or Philip's taup routine have a mechanism for dealing with that. If I do not know the units, how would that option help? George Helffrich george.helffrich at bris.ac.uk From sheila at blacknest.gov.uk Mon Jul 25 00:31:54 2011 From: sheila at blacknest.gov.uk (Sheila Peacock) Date: Mon, 25 Jul 2011 08:31:54 +0100 Subject: [SAC-HELP] Fwd: Re: Fwd: printed comment in transfer command Message-ID: <4E2D1BEA.9030502@blacknest.gov.uk> Dear Arthur and All, I got this from my colleague who has been using SAC for a long time. Sheila Peacock. -------- Original Message -------- Subject: Re: Fwd: [SAC-HELP] printed comment in transfer command Date: Mon, 25 Jul 2011 08:27:30 +0100 Sheila, this has probably been answered already. The value is not always "1.0000". On older versions of SAC, if you apply "transfer" to multiple waveforms simultaneously, then all but the first waveform are multiplied by the "scale" value in the sac header. I always assumed this was a bug or half-implemented feature so I always tried to avoid it! Sheila Peacock wrote: > > > -------- Original Message -------- > Subject: [SAC-HELP] printed comment in transfer command > Date: Wed, 6 Jul 2011 19:34:49 -0400 (EDT) > From: Arthur Snoke > To: SAC-help Listserv > > For all transfer commands, there is a line printed to the screen: > > Waveform multiplied by 1.000000 after deconvolution. > > So far as I can tell it, this line serves no purpose. If any of you know > a reason to keep this printed output, please let me know. > _______________________________________________ > sac-help mailing list > sac-help at iris.washington.edu > http://www.iris.washington.edu/mailman/listinfo/sac-help > . > From sheila at blacknest.gov.uk Mon Jul 25 00:49:29 2011 From: sheila at blacknest.gov.uk (Sheila Peacock) Date: Mon, 25 Jul 2011 08:49:29 +0100 Subject: [SAC-HELP] Fwd: printed comment in transfer command Message-ID: <4E2D2009.3040702@blacknest.gov.uk> My colleague adds that the current IRIS-released version, 101.4, also behaves this way. S. -------- Original Message -------- Subject: [SAC-HELP] Fwd: Re: Fwd: printed comment in transfer command Date: Mon, 25 Jul 2011 08:31:54 +0100 From: Sheila Peacock Organisation: AWE Blacknest To: sac-help at iris.washington.edu Dear Arthur and All, I got this from my colleague who has been using SAC for a long time. Sheila Peacock. -------- Original Message -------- Subject: Re: Fwd: [SAC-HELP] printed comment in transfer command Date: Mon, 25 Jul 2011 08:27:30 +0100 Sheila, this has probably been answered already. The value is not always "1.0000". On older versions of SAC, if you apply "transfer" to multiple waveforms simultaneously, then all but the first waveform are multiplied by the "scale" value in the sac header. I always assumed this was a bug or half-implemented feature so I always tried to avoid it! Sheila Peacock wrote: > > > -------- Original Message -------- > Subject: [SAC-HELP] printed comment in transfer command > Date: Wed, 6 Jul 2011 19:34:49 -0400 (EDT) > From: Arthur Snoke > To: SAC-help Listserv > > For all transfer commands, there is a line printed to the screen: > > Waveform multiplied by 1.000000 after deconvolution. > > So far as I can tell it, this line serves no purpose. If any of you know > a reason to keep this printed output, please let me know. > _______________________________________________ > sac-help mailing list > sac-help at iris.washington.edu > http://www.iris.washington.edu/mailman/listinfo/sac-help > . > _______________________________________________ sac-help mailing list sac-help at iris.washington.edu http://www.iris.washington.edu/mailman/listinfo/sac-help From snoke at vt.edu Mon Jul 25 04:19:43 2011 From: snoke at vt.edu (Arthur Snoke) Date: Mon, 25 Jul 2011 07:19:43 -0400 (EDT) Subject: [SAC-HELP] Fwd: printed comment in transfer command In-Reply-To: <4E2D2009.3040702@blacknest.gov.uk> References: <4E2D2009.3040702@blacknest.gov.uk> Message-ID: Sheila, Thanks for your note. At various times, it appears there has been some "optional" scaling within SAC. In a 1997 message from Peter Goldstein, "The default for scale is off (i.e., we don't multiply by calib anymore)." I think your colleague's memory may have been for versions of SAC2000 for which "calib" was used to rescale data. There is a header variable named SCALE that (like EVDP) "is not currently used." At the moment, waveforms produced by RDSEED have a value for SCALE that is "B058F04 Sensitivity:" in the RESP file but is not used in SAC, so far as I can tell. in my SAC e-mail archives, I find a message from George H in 1991 in which he talks about using the unused SCALE flag in the SAC header for instrument-correction stuff we were working on at that time. "I changed the CDSEIS code to include the digital sensitivity (aka gain) of each component as the SCALE variable in the header. As far as I can tell, SAC doesn't use the value, but it will preserve it in the header. I've not changed the value of the normalization constant in the poles and zeroes description, however. So, after you do your transfer command to remove the instrument response, you can say 'mul &n,SCALE&' to change the amplitude to some length unit." On Mon, 25 Jul 2011, Sheila Peacock wrote: > My colleague adds that the current IRIS-released version, 101.4, also > behaves this way. S. > > -------- Original Message -------- > Subject: [SAC-HELP] Fwd: Re: Fwd: printed comment in transfer command > Date: Mon, 25 Jul 2011 08:31:54 +0100 > From: Sheila Peacock > Organisation: AWE Blacknest > To: sac-help at iris.washington.edu > > Dear Arthur and All, > > I got this from my colleague who has been using SAC for a > long time. > > Sheila Peacock. > > -------- Original Message -------- > Subject: Re: Fwd: [SAC-HELP] printed comment in transfer command > Date: Mon, 25 Jul 2011 08:27:30 +0100 > > > Sheila, > > this has probably been answered already. > > The value is not always "1.0000". On older versions of SAC, if you apply > "transfer" to multiple waveforms simultaneously, then all but the first > waveform are multiplied by the "scale" value in the sac header. I always > assumed this was a bug or half-implemented feature so I always tried to > avoid it! > > > Sheila Peacock wrote: >> >> >> -------- Original Message -------- >> Subject: [SAC-HELP] printed comment in transfer command >> Date: Wed, 6 Jul 2011 19:34:49 -0400 (EDT) >> From: Arthur Snoke >> To: SAC-help Listserv >> >> For all transfer commands, there is a line printed to the screen: >> >> Waveform multiplied by 1.000000 after deconvolution. >> >> So far as I can tell it, this line serves no purpose. If any of you know >> a reason to keep this printed output, please let me know. From snoke at vt.edu Mon Jul 25 04:47:58 2011 From: snoke at vt.edu (Arthur Snoke) Date: Mon, 25 Jul 2011 07:47:58 -0400 (EDT) Subject: [SAC-HELP] Another unnecessary printout? Message-ID: Is the printout from RTREND of any use? SAC> r ./2006.253.14.59.45.4500.TA.N11A..BHZ.R.SAC SAC> rtrend Slope and standard deviation are: -0.0018373 0.0014481 Intercept and standard deviation are: 375.65 2.1152 Data standard deviation is: 336.38 Data correlation coefficient is: 0.0039891 SAC> My preference would be to not print it out. My second choice would be to have the printout appear only if the call was SAC> RTREND VERBOSE Comments? From neil at blacknest.gov.uk Mon Jul 25 06:58:44 2011 From: neil at blacknest.gov.uk (Neil Selby) Date: Mon, 25 Jul 2011 14:58:44 +0100 Subject: [SAC-HELP] printed comment in transfer command Message-ID: <4E2D7694.6090602@blacknest.gov.uk> Hello, hope this gets through! this is an example of the behaviour I described to Sheila: [neil at braeriach scratch]$ /sharedprograms/sac/v101.4/64/sac/bin/sac SEISMIC ANALYSIS CODE [06/07/2010 (Version 101.4)] Copyright 1995 Regents of the University of California SAC> r *SHZ*sac 20020511_000000.EKB10.SHZ.sac 20020511_000000.EKB1.SHZ.sac 20020511_000000.EKB2.SHZ.sac 20020511_000000.EKB3.SHZ.sac 20020511_000000.EKB4.SHZ.sac 20020511_000000.EKB5.SHZ.sac 20020511_000000.EKB6.SHZ.sac 20020511_000000.EKB7.SHZ.sac 20020511_000000.EKB8.SHZ.sac 20020511_000000.EKB9.SHZ.sac 20020511_000000.EKR10.SHZ.sac 20020511_000000.EKR1.SHZ.sac 20020511_000000.EKR2.SHZ.sac 20020511_000000.EKR3.SHZ.sac 20020511_000000.EKR4.SHZ.sac 20020511_000000.EKR5.SHZ.sac 20020511_000000.EKR6.SHZ.sac 20020511_000000.EKR7.SHZ.sac 20020511_000000.EKR8.SHZ.sac 20020511_000000.EKR9.SHZ.sac SAC> lh scale FILE: 20020511_000000.EKB10.SHZ.sac - 1 ----------------------------------- scale = 7.225000e-02 FILE: 20020511_000000.EKB1.SHZ.sac - 2 ---------------------------------- scale = 7.225000e-02 FILE: 20020511_000000.EKB2.SHZ.sac - 3 ---------------------------------- scale = 7.225000e-02 FILE: 20020511_000000.EKB3.SHZ.sac - 4 ---------------------------------- scale = 7.225000e-02 FILE: 20020511_000000.EKB4.SHZ.sac - 5 ---------------------------------- scale = 7.225000e-02 FILE: 20020511_000000.EKB5.SHZ.sac - 6 ---------------------------------- scale = 7.225000e-02 FILE: 20020511_000000.EKB6.SHZ.sac - 7 ---------------------------------- scale = 7.225000e-02 FILE: 20020511_000000.EKB7.SHZ.sac - 8 ---------------------------------- scale = 7.225000e-02 Waiting FILE: 20020511_000000.EKB8.SHZ.sac - 9 ---------------------------------- scale = 7.225000e-02 FILE: 20020511_000000.EKB9.SHZ.sac - 10 ---------------------------------- scale = 7.225000e-02 FILE: 20020511_000000.EKR10.SHZ.sac - 11 ----------------------------------- scale = 7.225000e-02 FILE: 20020511_000000.EKR1.SHZ.sac - 12 ---------------------------------- scale = 7.225000e-02 FILE: 20020511_000000.EKR2.SHZ.sac - 13 ---------------------------------- scale = 7.225000e-02 FILE: 20020511_000000.EKR3.SHZ.sac - 14 ---------------------------------- scale = 7.225000e-02 FILE: 20020511_000000.EKR4.SHZ.sac - 15 ---------------------------------- scale = 7.225000e-02 FILE: 20020511_000000.EKR5.SHZ.sac - 16 ---------------------------------- scale = 7.225000e-02 Waiting FILE: 20020511_000000.EKR6.SHZ.sac - 17 ---------------------------------- scale = 7.225000e-02 FILE: 20020511_000000.EKR7.SHZ.sac - 18 ---------------------------------- scale = 7.225000e-02 FILE: 20020511_000000.EKR8.SHZ.sac - 19 ---------------------------------- scale = 7.225000e-02 FILE: 20020511_000000.EKR9.SHZ.sac - 20 ---------------------------------- scale = 7.225000e-02 SAC> SAC> rmean SAC> taper SAC> trans from pol s EKA-SZ.pz to none freq 1 2 3 4 Extracting polezero response for EKB10 , SHZ ... Station (EKB10 ), Channel (SHZ ) Waveform multiplied by 1.000000 after deconvolution. Extracting polezero response for EKB1 , SHZ ... Station (EKB1 ), Channel (SHZ ) Nominal Calper not set. Setting Nominal Calper to -999.000000 to match Wfdisc Calper Sensor Calper not set. Setting Sensor Calper to 1.000000 to match Wfdisc Calper Response appears to be Normalized. Waveform appears to be unscaled. Wfdisc calib value is (0.072250). Waveform multiplied by 0.072250 after deconvolution. Extracting polezero response for EKB2 , SHZ ... Station (EKB2 ), Channel (SHZ ) Nominal Calper not set. Setting Nominal Calper to -999.000000 to match Wfdisc Calper Sensor Calper not set. Setting Sensor Calper to 1.000000 to match Wfdisc Calper Response appears to be Normalized. Waveform appears to be unscaled. Wfdisc calib value is (0.072250). Waveform multiplied by 0.072250 after deconvolution. Extracting polezero response for EKB3 , SHZ ... Station (EKB3 ), Channel (SHZ ) Nominal Calper not set. Setting Nominal Calper to -999.000000 to match Wfdisc Calper Sensor Calper not set. Setting Sensor Calper to 1.000000 to match Wfdisc Calper Response appears to be Normalized. Waveform appears to be unscaled. Wfdisc calib value is (0.072250). Waveform multiplied by 0.072250 after deconvolution. Extracting polezero response for EKB4 , SHZ ... Station (EKB4 ), Channel (SHZ ) Nominal Calper not set. Setting Nominal Calper to -999.000000 to match Wfdisc Calper Sensor Calper not set. Setting Sensor Calper to 1.000000 to match Wfdisc Calper Response appears to be Normalized. Waveform appears to be unscaled. Wfdisc calib value is (0.072250). Waveform multiplied by 0.072250 after deconvolution. Extracting polezero response for EKB5 , SHZ ... Station (EKB5 ), Channel (SHZ ) Nominal Calper not set. Setting Nominal Calper to -999.000000 to match Wfdisc Calper Sensor Calper not set. Setting Sensor Calper to 1.000000 to match Wfdisc Calper Response appears to be Normalized. Waveform appears to be unscaled. Wfdisc calib value is (0.072250). Waveform multiplied by 0.072250 after deconvolution. Extracting polezero response for EKB6 , SHZ ... Station (EKB6 ), Channel (SHZ ) Nominal Calper not set. Setting Nominal Calper to -999.000000 to match Wfdisc Calper Sensor Calper not set. Setting Sensor Calper to 1.000000 to match Wfdisc Calper Response appears to be Normalized. Waveform appears to be unscaled. Wfdisc calib value is (0.072250). Waveform multiplied by 0.072250 after deconvolution. Extracting polezero response for EKB7 , SHZ ... Station (EKB7 ), Channel (SHZ ) Nominal Calper not set. Setting Nominal Calper to -999.000000 to match Wfdisc Calper Sensor Calper not set. Setting Sensor Calper to 1.000000 to match Wfdisc Calper Response appears to be Normalized. Waveform appears to be unscaled. Wfdisc calib value is (0.072250). Waveform multiplied by 0.072250 after deconvolution. Extracting polezero response for EKB8 , SHZ ... Station (EKB8 ), Channel (SHZ ) Nominal Calper not set. Setting Nominal Calper to -999.000000 to match Wfdisc Calper Sensor Calper not set. Setting Sensor Calper to 1.000000 to match Wfdisc Calper Response appears to be Normalized. Waveform appears to be unscaled. Wfdisc calib value is (0.072250). Waveform multiplied by 0.072250 after deconvolution. Extracting polezero response for EKB9 , SHZ ... Station (EKB9 ), Channel (SHZ ) Nominal Calper not set. Setting Nominal Calper to -999.000000 to match Wfdisc Calper Sensor Calper not set. Setting Sensor Calper to 1.000000 to match Wfdisc Calper Response appears to be Normalized. Waveform appears to be unscaled. Wfdisc calib value is (0.072250). Waveform multiplied by 0.072250 after deconvolution. Extracting polezero response for EKR10 , SHZ ... Station (EKR10 ), Channel (SHZ ) Nominal Calper not set. Setting Nominal Calper to -999.000000 to match Wfdisc Calper Sensor Calper not set. Setting Sensor Calper to 1.000000 to match Wfdisc Calper Response appears to be Normalized. Waveform appears to be unscaled. Wfdisc calib value is (0.072250). Waveform multiplied by 0.072250 after deconvolution. Extracting polezero response for EKR1 , SHZ ... Station (EKR1 ), Channel (SHZ ) Nominal Calper not set. Setting Nominal Calper to -999.000000 to match Wfdisc Calper Sensor Calper not set. Setting Sensor Calper to 1.000000 to match Wfdisc Calper Response appears to be Normalized. Waveform appears to be unscaled. Wfdisc calib value is (0.072250). Waveform multiplied by 0.072250 after deconvolution. Extracting polezero response for EKR2 , SHZ ... Station (EKR2 ), Channel (SHZ ) Nominal Calper not set. Setting Nominal Calper to -999.000000 to match Wfdisc Calper Sensor Calper not set. Setting Sensor Calper to 1.000000 to match Wfdisc Calper Response appears to be Normalized. Waveform appears to be unscaled. Wfdisc calib value is (0.072250). Waveform multiplied by 0.072250 after deconvolution. Extracting polezero response for EKR3 , SHZ ... Station (EKR3 ), Channel (SHZ ) Nominal Calper not set. Setting Nominal Calper to -999.000000 to match Wfdisc Calper Sensor Calper not set. Setting Sensor Calper to 1.000000 to match Wfdisc Calper Response appears to be Normalized. Waveform appears to be unscaled. Wfdisc calib value is (0.072250). Waveform multiplied by 0.072250 after deconvolution. Extracting polezero response for EKR4 , SHZ ... Station (EKR4 ), Channel (SHZ ) Nominal Calper not set. Setting Nominal Calper to -999.000000 to match Wfdisc Calper Sensor Calper not set. Setting Sensor Calper to 1.000000 to match Wfdisc Calper Response appears to be Normalized. Waveform appears to be unscaled. Wfdisc calib value is (0.072250). Waveform multiplied by 0.072250 after deconvolution. Extracting polezero response for EKR5 , SHZ ... Station (EKR5 ), Channel (SHZ ) Nominal Calper not set. Setting Nominal Calper to -999.000000 to match Wfdisc Calper Sensor Calper not set. Setting Sensor Calper to 1.000000 to match Wfdisc Calper Response appears to be Normalized. Waveform appears to be unscaled. Wfdisc calib value is (0.072250). Waveform multiplied by 0.072250 after deconvolution. Extracting polezero response for EKR6 , SHZ ... Station (EKR6 ), Channel (SHZ ) Nominal Calper not set. Setting Nominal Calper to -999.000000 to match Wfdisc Calper Sensor Calper not set. Setting Sensor Calper to 1.000000 to match Wfdisc Calper Response appears to be Normalized. Waveform appears to be unscaled. Wfdisc calib value is (0.072250). Waveform multiplied by 0.072250 after deconvolution. Extracting polezero response for EKR7 , SHZ ... Station (EKR7 ), Channel (SHZ ) Nominal Calper not set. Setting Nominal Calper to -999.000000 to match Wfdisc Calper Sensor Calper not set. Setting Sensor Calper to 1.000000 to match Wfdisc Calper Response appears to be Normalized. Waveform appears to be unscaled. Wfdisc calib value is (0.072250). Waveform multiplied by 0.072250 after deconvolution. Extracting polezero response for EKR8 , SHZ ... Station (EKR8 ), Channel (SHZ ) Nominal Calper not set. Setting Nominal Calper to -999.000000 to match Wfdisc Calper Sensor Calper not set. Setting Sensor Calper to 1.000000 to match Wfdisc Calper Response appears to be Normalized. Waveform appears to be unscaled. Wfdisc calib value is (0.072250). Waveform multiplied by 0.072250 after deconvolution. Extracting polezero response for EKR9 , SHZ ... Station (EKR9 ), Channel (SHZ ) Nominal Calper not set. Setting Nominal Calper to -999.000000 to match Wfdisc Calper Sensor Calper not set. Setting Sensor Calper to 1.000000 to match Wfdisc Calper Response appears to be Normalized. Waveform appears to be unscaled. Wfdisc calib value is (0.072250). Waveform multiplied by 0.072250 after deconvolution. SAC> plotting the data shows that all but the first channel has been multiplied by the "scale" factor 0.072250. If you don't want to multiply by scale (which you often don't) then care needs to be taken. I assume that the above behaviour is not intended. Also I don't think it's fair to say that the "scale" value is unused - it's unused when rdseed generated sac files are being used, certainly. Neil Selby AWE Blacknest From snoke at vt.edu Tue Jul 26 13:57:45 2011 From: snoke at vt.edu (Arthur Snoke) Date: Tue, 26 Jul 2011 16:57:45 -0400 (EDT) Subject: [SAC-HELP] printed comment in transfer command In-Reply-To: <4E2D7694.6090602@blacknest.gov.uk> References: <4E2D7694.6090602@blacknest.gov.uk> Message-ID: Neil (and Sheila), Brian and I have run several experiments and find that indeed, there is an error in runs with v101.4 and earlier when a single transfer call is applied to more than one file in memory if the header variable SCALE is defined, the NWFID is not defined, and the file is the first in the list of files. The bug can occur when only one file has been read. Reading in one of your files twice and applying your transfer call, one gets different depmin and depmax for the two (identical) files: SEISMIC ANALYSIS CODE [06/07/2010 (Version 101.4)] Copyright 1995 Regents of the University of California SAC> r ./20020511_000000.EKB1.SHZ.sac ./20020511_000000.EKB1.SHZ.sac SAC> rmean SAC> taper SAC> transfer from polezero s ./EKA-SZ.pz to none freq 1 2 3 4 Extracting polezero response for EKB1 , SHZ ... Station (EKB1 ), Channel (SHZ ) Waveform multiplied by 1.000000 after deconvolution. Extracting polezero response for EKB1 , SHZ ... Station (EKB1 ), Channel (SHZ ) Nominal Calper not set. Setting Nominal Calper to -999.000000 to match Wfdisc Calper Sensor Calper not set. Setting Sensor Calper to 1.000000 to match Wfdisc Calper Response appears to be Normalized. Waveform appears to be unscaled. Wfdisc calib value is (0.072250). Waveform multiplied by 0.072250 after deconvolution. SAC> lh scale depmin depmax FILE: ./20020511_000000.EKB1.SHZ.sac - 1 ------------------------------------ scale = 1.000000e+00 depmin = -1.396522e+01 depmax = 1.375477e+01 FILE: ./20020511_000000.EKB1.SHZ.sac - 2 ------------------------------------ scale = 1.000000e+00 depmin = -1.008987e+00 depmax = 9.937820e-01 SAC> The SCALE was indeed used for processing CSS files for which CALIB was used and for which NWFID (Css 3.0 wavform id) is defined. For v101.5 SCALE will truly not be used (at least in TRANSFER). For now, if one undefines SCALE, one should get consistent results: SAC> r ./20020511_000000.EKB1.SHZ.sac ./20020511_000000.EKB1.SHZ.sac SAC> ch SCALE undef dot dot dot SAC> lh scale depmin depmax FILE: ./20020511_000000.EKB1.SHZ.sac - 1 ------------------------------------ scale = 1.000000e+00 depmin = -1.396522e+01 depmax = 1.375477e+01 FILE: ./20020511_000000.EKB1.SHZ.sac - 2 ------------------------------------ scale = 1.000000e+00 depmin = -1.396522e+01 depmax = 1.375477e+01 SAC> We will put some warnings in the help file for READCSS to alert users that use CALIB that it is not recognized in SAC v101.5. Arthur p.s. Thanks, Sheila for helping us find an error we hopefully have solved. From aj.schaeffer at gmail.com Thu Jul 28 01:23:02 2011 From: aj.schaeffer at gmail.com (Andrew Schaeffer) Date: Thu, 28 Jul 2011 09:23:02 +0100 Subject: [SAC-HELP] sac library error codes Message-ID: Hello, Does anybody know a reference that lists the different error codes and syntax for the C/Fortran library routines packaged with SAC? I didn't see those in the online manual. thanks, Andrew -------------- next part -------------- An HTML attachment was scrubbed... URL: From savage at uri.edu Thu Jul 28 07:08:41 2011 From: savage at uri.edu (Brian Savage) Date: Thu, 28 Jul 2011 10:08:41 -0400 Subject: [SAC-HELP] sac library error codes In-Reply-To: References: Message-ID: <2FA7FB14-6AF8-4F8B-A43A-792F450D8EED@uri.edu> Andrew, Look in ${SACAUX}/messages Brian On Jul 28, 2011, at 4:23 AM, Andrew Schaeffer wrote: > Hello, > > Does anybody know a reference that lists the different error codes and syntax for the C/Fortran library routines packaged with SAC? I didn't see those in the online manual. > > thanks, > Andrew > _______________________________________________ > sac-help mailing list > sac-help at iris.washington.edu > http://www.iris.washington.edu/mailman/listinfo/sac-help From ndikumeric at yahoo.com Thu Jul 28 14:44:14 2011 From: ndikumeric at yahoo.com (ndoh ndikum) Date: Thu, 28 Jul 2011 14:44:14 -0700 (PDT) Subject: [SAC-HELP] Help to pick p & s phases, get instrument gain ... Message-ID: <1311889454.31867.YahooMailNeo@web39322.mail.mud.yahoo.com> good day, I am currently working with some sac waveforms, wishing to locate the events in order to futher carry out inversions but I am faced with the following problems: - I have succeeded to pick the p and s phases in some of the data files but can't for others. could I be helped with the p and s phases of the accompanying attached sac data files. - could I also be helped with some basic lecture notes on phase identification and picking. - how can I instrument gain of these sac files in particular and any other sac file I come across in general? - how do know if the have the same instrument response? - what is the procedure to choose the appropriate filter windows to use for a specific data type? what tips are available? I will be grateful for your help! Eric. ? --------------------------------------------------- NDIKUM ERIC NDOH, C/O C.M.F.I. YAOUNDE, P.O. Box 6090, CAMEROON, WEST AFRICA . 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Name: 2005082215100.01.CM06.BHZ_02 Type: application/octet-stream Size: 48632 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: 2005084011600.01.CM06.BHZ_02 Type: application/octet-stream Size: 48632 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: 2005252074500.01.CM09.BHZ_02 Type: application/octet-stream Size: 48632 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: 2006023210300.00.CM01.BHZ_02 Type: application/octet-stream Size: 48632 bytes Desc: not available URL: From snoke at vt.edu Thu Jul 28 16:43:03 2011 From: snoke at vt.edu (Arthur Snoke) Date: Thu, 28 Jul 2011 19:43:03 -0400 (EDT) Subject: [SAC-HELP] sac library error codes Message-ID: We are planning to put the message file into a help file, which will then be as well in the online manual. We would appreciate it if folks could look at the file and advise us of any errors, inconsistencies, or omissions. No need to copy the whole list on this. Thanks, Arthur ---------- Forwarded message ---------- Date: Thu, 28 Jul 2011 10:08:41 -0400 From: Brian Savage To: Andrew Schaeffer Cc: Sac Help Subject: Re: [SAC-HELP] sac library error codes Andrew, Look in ${SACAUX}/messages Brian On Jul 28, 2011, at 4:23 AM, Andrew Schaeffer wrote: > Hello, > > Does anybody know a reference that lists the different error codes and > syntax for the C/Fortran library routines packaged with SAC? I didn't > see those in the online manual. > > thanks, > Andrew From sheila at blacknest.gov.uk Fri Jul 29 00:35:31 2011 From: sheila at blacknest.gov.uk (Sheila Peacock) Date: Fri, 29 Jul 2011 08:35:31 +0100 Subject: [SAC-HELP] Fwd: Help to pick p & s phases, get instrument gain ... Message-ID: <4E3262C3.5030603@blacknest.gov.uk> Dear Eric, You need a lot more help and time than I can devote, but here is a start. I hope that other members of this list can point you to web resources (perhaps some that they have written themselves). Regards, Sheila Peacock. -------- Original Message -------- Subject: [SAC-HELP] Help to pick p & s phases, get instrument gain ... Date: Thu, 28 Jul 2011 14:44:14 -0700 (PDT) From: ndoh ndikum Reply-To: ndoh ndikum To: chad at iris.washington.edu CC: sac-help at iris.washington.edu good day, I am currently working with some sac waveforms, wishing to locate the events in order to futher carry out inversions but I am faced with the following problems: - I have succeeded to pick the p and s phases in some of the data files but can't for others. could I be helped with the p and s phases of the accompanying attached sac data files. ## Have you used a set of traveltime tables to predict the expected arrival times of your P and S phases, given the origin time of the event? This is also useful to distinguish the phases from other phases that might arrive at nearly the same time. ## For S phases, it is useful to use the horizontal components if your seismometers are three-component instruments. - could I also be helped with some basic lecture notes on phase identification and picking. - how can I instrument gain of these sac files in particular and any other sac file I come across in general? - how do know if the have the same instrument response? ## Information about instrument responses should be provided by the operator of the seismic network. It is not usually encoded in SAC files, although if your SAC files came from SEED files you might be able to extract instrument responses by running "rdseed" and answering "yes" to "extract responses"; the SAC "transfer" command with type "evalresp" can then be used to remove the instrument response. ## If the seismometers are made by Guralp you can find the instrument response if you can find out the serial numbers of the seismometer and the digitiser. You then send a simple email to "caldoc at guralp.com" with the serial number in the subject line. You will receive a Microsoft Word document containing the response information. Beware that the document for digitiser responses cannot be read in OpenOffice, only in Microsoft Word proper. Furthermore, the poles and zeros are given in terms of velocity (or sometimes acceleration) in Hz not radians, and have to be multiplied by 2pi and an extra zero at (0.0, 0.0) added to make them into displacement in radians suitable for use in SAC. Also you have to find out whether the seismometer is connected "differentially" to the digitiser, in which case the "2x" shown in the data sheet has to be applied. - what is the procedure to choose the appropriate filter windows to use for a specific data type? what tips are available? ## There are no hard and fast rules other than not to filter too severely i.e. not use a narrow passband or steep slopes on the filter, for picking. The CTBTO IDC uses 0.8-4.5 Hz for picking, but this is not appropriate for large events (too high; arrivals from large events shouldn't need bandpass filtering), or small events (too low)). If there is very high-frequency or very low-frequency noise (frequency far away from the signal frequency) then a suitable lowpass or highpass filter will be seen to remove it. Several of your seismograms benefit from a lowpass filter. ## You should always make a note of the filter applied along with your pick time, so that you can go back and check it. ## If the earthquake is a long way from your network (i.e. much farther than the diameter of your network) then comparing seismograms from all the stations in the network, lined up on the expected P-wave arrival time at each station, should help you identify phases. I will be grateful for your help! Eric. --------------------------------------------------- NDIKUM ERIC NDOH, C/O C.M.F.I. YAOUNDE, P.O. Box 6090, CAMEROON, WEST AFRICA . TEL:(237) 75 17 91 66