NORTHERN CALIFORNIA EARTHQUAKE DATA CENTER RESEARCH ACCOUNT USER MANUAL Rick Lester (1) Douglas Neuhauser (2) David Oppenheimer (1) Barbara Romanowicz (2) Lind Gee (2) For additional information or assistance contact: Rick Lester lester@andreas.wr.usgs.gov Doug Neuhauser doug@seismo.berkeley.edu May 26, 1998 - 2 - (1) USGS, Menlo Park, CA (2) Seismological Laboratory, UC, Berkeley, CA May 26, 1998 - 3 - Acknowledgements: We acknowledge the staffs of the UCB Seismological Labora- tory and the NCSN who maintain, operate, and process the data recorded by the networks. May 26, 1998 - 4 - USER MANUAL NORTHERN CALIFORNIA EARTHQUAKE DATA CENTER Table of Contents 1.0 Introduction 1.1 Conventions 1.2 How to access the Data Center 2.0 Catalog, Phase, and Focal Mechanism Data 2.1 Description 2.2 Retrieval of catalog, phase and focal mechanism data 2.2.1Program eqselect 2.2.2Program extract 2.2.3Program catlist 3.0 Waveform Data 3.1 Description of waveform data 3.2 Retrieving of UCB broadband data 3.2.1Program sdata 3.2.2Program rdseed 3.2 Retrieval of NCSN waveform data 3.3.1Determining event ID 3.2.2Retreiving of waveform data 3.2.3Converting to CUSP (VAX) format 3.2.4Retrieving of data in AH Format 3.2.5Retrieving of data in SAC format Appendix A Setting up an account at the Data Center Appendix B Table of utilities available at the Data Center May 26, 1998 - 5 - 1.0 INTRODUCTION The Northern California Earthquake Data Center (NCEDC) was established to provide easy access to central and northern California digital earthquake data. The NCEDC is located at the University of California, Berkeley and is operated jointly with the U.S. Geological Survey (USGS) in Menlo Park, CA. It has been accessible to users in the scientific community through Internet since mid-1992. The Data Center provides an archive for parametric and waveform data from two regional networks: the Northern California Seismic Net- work (NCSN) operated by the USGS and the Berkeley Digital Seismic Network (BDSN) operated by the Seismological Labora- tory at the University of California, Berkeley. This manual describes the types of data stored at the NCEDC and how users may retrieve the data. The purpose of this manual is to give the Data Center user a description of the available data and examples of how to retrieve the data using the utilities at the Data Center. 1.1 Conventions Program names are in bold lower case type. Example commands which the user would enter are in bold type. indicates the user should enter a carriage return. Filenames are in italic type. A number of programs at the data center are designed to read from files or from the terminal, and to write to the termi- nal. This allows programs to be "piped" together to perform more complex operations. Examples of this are given in sec- tions 2.2.2 and 2.2.3. of this manual. 1.2 Accessing the Northern California Earthquake Data Center The NCEDC is accessible via the Internet. The data center establishs individual accounts for each user accessing the data center. It is assumed that users are either familiar with or will obtain their own support on the use of the Unix operating system. The data center cannot provide consulting support on questions not directly related to the data center. To request an account at the data center, see the instruc- tions in Appendix A. May 26, 1998 - 6 - 2.0 CATALOG, PHASE, and FOCAL MECHANISM DATA 2.1 Description Catalog, phase, and focal mechanism data from two seismic networks are stored at the Data Center: 1. Northern California Seismic Network (NCSN) operated by the USGS, Menlo Park: * Catalog, phase and focal mechanism listings from 1967 to the present. 2. University of California (UCB), Berkeley Seismological Laboratory: * Catalog listings from 1910 to the present. * Phase, amplitude and scalar moment data from 1984 to the present. The format of the data is described in the following manual pages: tab (/); c c l l . Manual Page/Description calnet.catalog/Format of NCSN earthquake location files calnet.phase/Format of NCSN earthquake phase files calnet.mech/Format of NCSN first motion focal mechanism files ucb.catalog/Format of UCB earthquake location file ucb.phase/Format of UCB earthquake phase files Programs for retrieving the catalog, phase and mechanism data are described in the following manual pages: tab (/); c c l l . Manual Page/Description eqselect/Retrieve catalog and mechanism data extract/Retrieve phase data catlist/Generate readable output of catalog 2.2 Retrieving catalog, phase, and mechanism data. 2.2.1 Program eqselect Programs eqselect allows for the retrieval of catalog and mechanism data from the NCSN and UCB catalogs. Below are examples of typical searches from the catalog May 26, 1998 - 7 - using program eqselect. Example 1: To select all aftershocks of the Loma Prieta earthquake with magnitude 4.0 or greater within the first 24 hours of the mainshock from the NCSN (calnet) catalog and write the results to file loma.ncsn: eqselect -format calnet -magnitude 4.0 8.0 -time 891018000400. \ 891019000400. -catalog -latitude 36.5 37.5 \ -longitude -122.5 -121.5 > loma.ncsn Example 2. To select the focal mechanisms for events described in example 1 and write the results to file loma.mech: eqselect -format mech -magnitude 4.0 8.0 -time 891018000400. \ 891019000400. -catalog -latitude 36.5 37.5 -longitude -122.5 -121.5 \ > loma.mech Example 3. To select the earthquakes described in example 1 from the UCB catalog and write to file loma.ucb: eqselect -format ucb -magnitude 4.0 8.0 -time 891018000400. \ 891019000400. -catalog -latitude 36.5 37.5 -longitude -122.5 -121.5 \ > loma.ucb The program eqselect has other options which are described in the online manual page. 2.2.2 Program extract Program extract will extract the complete event and phase May 26, 1998 - 8 - information for selected events from either the NCSN phase files or the UCB phase files. CALNET phase files are in Hypoinverse format, and UCB phase phases are in UCB phase file format. Below are examples of retrieval of phase data from the NCSN and UCB catalog: Example 1. To retrieve phase data for all aftershocks of the Loma Prieta earthquake with magnitude 4.0 or greater within the first 24 hours of the mainshock using file gen- erated by eqselect: First, create file loma.ncsn with list of events from the NCSN catalog: eqselect -format calnet -magnitude 4.0 8.0 -time 891018000400. \ 891019000400. -catalog -latitude 36.5 37.5 \ -longitude -122.5 -121.5 > loma.ncsn Second, retrieve the phase data and write to file loma_ncsn.phases: extract -p -f calnet -e loma.ncsn > loma_ncsn.phases where: -p specifies that the online phase files are to be used. -f Specifies the NCSN (calnet) catalog is be searched. The input catalog file and output file will be in the calnet format. -e Specifies the file loma.ncsn contains the events, one per line, for which event and phase informa- tion should be extracted. Example 2. To retrieve phase data as described in example 1 using pipes: May 26, 1998 - 9 - eqselect -format calnet -magnitude 4.0 8.0 -time 891018000400. \ 891019000400. -catalog -latitude 36.5 37.5 \ -longitude -122.5 -121.5 | extract -p -f calnet > loma_ncsn.phases Example 3: To retrieve phase data as in example 1 from the UCB catalog: First, select the list of events from the UCB catalog: eqselect -format ucb -magnitude 4.0 8.0 -time 891018000400. \ 891019000400. -catalog -latitude 36.5 37.5 -longitude -122.5 -121.5 \ > loma.ucb Second, retrieve the phase data and write to file loma_ucb.phases: extract -p -f ucb -e loma.ucb >loma_ucb.phases 2.2.3 Program catlist Program catlist reads a NCSN or UCB catalog file and displays a subset of the information in more readable for- mat. Example: To display the contents of file loma.ncsn format to the screen: catlist loma.ncsn The output displayed will be: Date Time Lat Lon Depth Mag Nst Gap Clo RMS Event ID ------------------------------------------------------------------------------ May 26, 1998 - 10 - 1989/10/18 00:04:15.26 37.04 -121.88 16.79 7.00 84 70 1 0.08 216859 1989/10/18 00:07:15.21 37.23 -121.94 14.30 4.70 11 82 16 0.27 10090521 1989/10/18 00:07:43.36 36.99 -121.74 14.78 4.70 15 122 9 0.13 10090522 1989/10/18 00:08:22.04 37.08 -121.86 12.48 4.40 14 112 3 0.22 10090523 Example 2. To write the output of catlist to file loma.out with input loma.ucb in UCB format: catlist -f ucb loma.ucb loma.out Example 3. To retrieve all earthquakes with magnitude greater than 6.0 and display the output to the screen: eqselect -format ucb -catalog -magnitude 6.0 10.0 | catlist -f ucb Other options of program catlist are described in the online manual page. May 26, 1998 - 11 - 3.0 WAVEFORM DATA 3.1 Description of Waveform Data The following waveform data are currently stored online at the NCEDC: 1. UCB Broadband Data Continuous and triggered 24 bit digital broadband data streams from 1991 to the present in Mini-SEED format. Digital 16-bit data from 3 broadband stations from the time period 1987-1991 stored in Mini-SEED format. 2. NCSN 12-bit Digital Data Local and regional event data recorded by the NCSN since 1984 are stored in a variation of the CUSP for- mat. The CUSP format includes a 'mem' and 'grm' file for each event. The 'mem' file contains pointers to individual waveforms in the 'grm' or waveform file in addition to analysis results. The 'grm' file contains the waveform data in big-endian (e.g., SUN) byte order format. Digital seismograms are online for the time periods: March 1984 - March 1985 November 1988 - present April 1985 - October 1988: incomplete. 3.2 Retrieval of UCB Broadband Data Retrieval of the broadband seismograms is performed using programs sdata, which creates full SEED volumes, or qdata, which retrieves just the native SEED data records. Most external users should use sdata to create full SEED volumes. This will allow data conversion to other formats with the use of the rdseed program from IRIS. The examples given below use sdata. NOTE: When using ftp to transfer the data files to your local computer, use the binary option. 3.2.1 Program sdata Program sdata extracts digital broadband seismic data and May 26, 1998 - 12 - creates a SEED volume containing the specified stations and channels for the specified time interval(s). Multi- ple sdata commands can be used to stage information for the subsequent creation of a single SEED volume. The SEED volume can be read by the IRIS rdseed program to extract instrument responses and data in various formats. You may optionally create a dataless SEED volume that contains only the station and instrument responses for the specified stations and channels. Some examples of sdata usage: Example 1. To retrieve 10 minutes of VBB data from MHC: sdata -f 92.176,11:43 -s 10M -o mhc.seed MHC 'BH*' where: -f 92.176,11:43 Specifies the beginning time window for which data is desired. In this example, the start time is year=1992, day of year=176, hour=11, and minute=43. Time may be specified in the following for- mats: [19]yy/mm/dd/hh:mm:ss.ffff [19]yy/mm/dd.hh:mm:ss.ffff [19]yy/mm/dd,hh:mm:ss.ffff [19]yy.ddd.hh:mm:ss.ffff [19]yy.ddd,hh:mm:ss.ffff [19]yy,ddd,hh:mm:ss.ffff where the first format specifies the year, month, day, and time, and the second format specifies year, julian day, and time. All trailing components of the date_time are optional, and if not specified, are assumed to be 0. -s 10M Specifies that 10 minutes of data are to be retrieved starting with time specified in the "-f" option. -o mhc.seed Specifies the filename of the SEED volume. Example 2. May 26, 1998 - 13 - To retrieve 4 hours of VLP data from stations SAO, BKS, and MHC sdata -f 92.176,11:43 -s 4H -o arc.seed SAO,BKS,MHC VH{Z,N,E} Example 3: To retrieve all instrument responses for a 4 year period. sdata -I -f 90.001 -s 4y -o instr.seed '*' '*' where: -I Specifies that the SEED volume should contain only instrument responses for the specified stations and channels. The user is referred to the online manual page for descrip- tion of additional options and features. 3.2.2 Program rdseed Program rdseed, developed by IRIS, reads a SEED format input file or tape and allows the user to retrieve instrument response information or convert SEED data to other formats. In order to extract data and convert to other formats, the user must run rdseed in User Prompt Mode. To do this, type the following to the prompt: rdseed The online manual page gives details of rdseed operation and options. 3.3 Retrieval of NCSN Waveform Data NCSN CUSP seismograms are stored in a single file per event in big-endian (e.g., SUN) byte order with no header informa- tion in the file. Pointers to individual seismograms within the event file are found in the binary 'mem' file or the 'G' card of the ascii-mem file. Retrieval of NCSN waveform data requires two steps: First: Determine the NCSN event numeric identifier. Second: Using the event id, retrieve the waveform data using programs: getmem, getseis, cusp2ah, or cusp2sac. May 26, 1998 - 14 - tab (/); c c l l . Manual Page/Description getmem/Retrieval of CUSP mem file. getseis/Retrieval CUSP grm (waveform) data cusp2ah/Retrieval of data in ah format cusp2sac/Retrieval of data in sac format NOTE: When using ftp to transfer the data files to your local computer, use the binary option. 3.3.1 Determining event id To determine the event id, use program eqselect and catlist described in section 2.2 of this manual. 3.3.2 Retrieving the waveform data To retrieve mem and grm files for event with id 392798: getmem 392798 getseis 392798 The appropriate mem and grm file will be stored in your local directory. The grm (waveform file) will be in UNIX compressed format. Before using the file, you must uncompress it using: uncompress 329798.Z 3.3.3 Converting to CUSP (VAX) format To convert the grm file for event 392798 to CUSP (VAX) format: Step 1: Retrieve the seismogram with getseis as described above. getseis 392798 Step 2: Uncompress the seismogram file: uncompress 392798.Z Step 3: Use the program dd to convert the waveform file from big-endian byte order to little- endian (VAX or PC) byte order: dd if=392798 of=392798.grm conv=swab May 26, 1998 - 15 - 3.3.4 Retrieving Data in AH Format To retrieve a seismogram in ah or ahxdr format use pro- gram cusp2ah. When using cusp2ah, it is not necessary to retrieve the 'mem' and 'grm' files. Program cusp2ah will use the online 'mem' and 'grm' files directly. The online manual page gives the full range of options. In the example below, the seismogram for event 392798 will be retrieved and converted to ahxdr format. cusp2ah 392798 The seismogram will be stored in your local directory with the filename 392798.xdr. 3.3.5 Retrieve seismogram in SAC format Use program cusp2sac to retrieve seismogram in SAC for- mat. When using cusp2sac, it is not necessary to retrieve the 'mem' and 'grm' files. Program cusp2sac will use the online 'mem' and 'grm' files directly. To retrieve event 392798 in SAC format: cusp2sac 392798 The seismogram will be stored in your local directory as a series of SAC files, one for each channel in the original seismogram file. May 26, 1998 - 16 - A.1: Accessing the Northern California Earthquake Data Center The Northern California Earthquake Data Center (NCEDC) is accessible via the Internet. Initially, the data center will establish individual accounts for each user accessing the data center. In the future we may migrate to a single publicly-accessible account similar to the IRIS bulletin board system. It is assumed that users are either familiar with or will obtain their own support on the use of the Unix operating system. The data center cannot provide consulting support on questions not directly related to the data center. Host Name: quake.geo.berkeley.edu Internet address: 128.32.149.106 Computer: Sun SPARCstation 2 Operating system: SunOS (Unix) To request an account at the data center: 1. Use telnet to connect to quake.geo.berkeley.edu. Depending on your local computer configuration, you may have to use the Internet address of the machine instead of the hostname: telnet quake.geo.berkeley or telnet 128.32.149.106 2. Login to special account "bulletin", which has a password of "board". 3. Select the option to request an account. It is currently the only option available, other than "quit". You will be prompted for information such as your name, address, institutional affiliation, email address, and phone number. 4. You will should be contacted within 2 working days with your account information. If you do not hear within this time period, please contact: Douglas Neuhauser Seismological Laboratory Earth Science Building, University of California, Berkeley CA 94720 510-642-0931 5. This computer account is to be used strictly for accessing and retrieving data explicitly provided by the data center. Any other use consititutes fraud, and will be dealt with accordingly. See the sample session on the next page for an account request. May 26, 1998 - 17 - SAMPLE SESSION telnet quake.geo.berkeley.edu Trying 128.32.149.106 ... Connected to quake.geo.berkeley.edu. Escape character is '^]'. SunOS UNIX (quake.geo.berkeley.edu) login: bulletin Password: Last login: Mon Dec 7 11:14:13 from brkseis10.berkel ************************************************************************ Northern California Seismic Data Center ************************************************************************ Welcome to the UCB/USGS Northern California Seismology Data Center. Your host is: quake.geo.berkeley.edu Type "man info" to get more information about available resources. ************************************************************************ Welcome to the UCB/USGS Seismology Data Center Enter 'a' to request an account Enter 'q' to QUIT Enter your selection: a UC Berkeley Seismological Laboratory / USGS Seismology Data Center User ID request form: Please answer the following questions: (Terminate each reply with a 'return'.) (Type a control-D to abort account request.) Full Name: Joe Smith Institution/Organization/Company: Podunk U, Dept of Seismology Full Address (1 line): 123 Earth Sciences Building, Podunk U, Podunk, NY 14882 Office Phone #: 800-555-1212 Internet/Bitnet address (0=none): joesmith@geo.podunk.edu preferred user ID name: joesmith request logged... You will be contacted at the above address with information about your account. If you have not heard by the end of two working days, please resubmit your request, and if that does not work, please call 510-642-0931 or 510-642-3977 Thank you. Enter 'a' to request an account Enter 'q' to QUIT May 26, 1998 - 18 - Enter your selection: q Connection closed by foreign host. May 26, 1998 - 19 - A.2 HELP FILES AT THE DATA CENTER Information about NCEDC data and utilities are available by typing the following commands: tab (!); c c lw(2i) lw(4i) . Manual Page!Description man info!General information on data available at the data center man eqselect!Program documentation for obtaining earthquake !location data man extract!Program docu- mentation for obtaining earthquake !phase data man calnet!Overview of types of NCSN data available at the data center man calnet.catalog!Format of NCSN earthquake location files man calnet.phase!Format of NCSN earthquake phase files man calnet.mech!Format of NCSN first motion focal mechanism files man ascii_mem!Format of ASCII representation of CUSP .mem files man getmem!Program documentation for obtaining CUSP .mem files man getseis!Program documentation for obtaining CUSP seismograms man cusp2ah!Program documentation for converting seismograms !to ahxdr format man cusp2sac!Program documentatin for converting seismograms !to SAC format man ucb!Overview of type of UCB data available at the data center man ucb.catalog!Format of UCB earthquake location files man ucb.phase!Format of UCB earth- quake phase files man qdata!Program documentation for obtaining UCB waveform !data as Steim-1 compressed data blocks man sdata!Program documentation for obtaining UCB waveform !data as SEED volumes man rdseed!Program documentation for converting SEED format !files to other formats more /data/dc1/calnet/parameters/history Documentation on date of signifi- cant changes at data center May 26, 1998