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WILBER II is the new and improved version of our trusty seismic event browser. If you are familiar with the old version of WILBER, you shouldn't have any trouble navigating through the new version. The functionality is basically the same but with a few improvements. It's the "back end" that has changed dramatically.

If you are new to WILBER, this brief outline of its functionality should help you on your way to browsing and downloading quality earthquake data.

What you see:

Page 1 - Event Selection, Step 1

WILBER II allows you to select from a catalog of events for which ORFEUS has event based data. To begin, select a time period from the quarterly list (example at right) to display a map showing that quarter's seismic events. The default time period is the last 90 days.

You can view all events for your selected quarter or view a subset of events within a given radius from a selected event. The default radius is 5 degrees but you can select up to 60 degrees for your search. How does this help? If you have several events that occurred in the same geographic area it will be hard to select just one of them from the map. The radius selection narrows down your list of events from which to choose (on the next page). You may also be interested in seeing how many events occurred within a certain radius of another event.

Once you have selected a spot on the map or clicked the link for all events, the list of events will be presented on the next page.


Page 2 - Event Selection, Step 2

Here you should see a list of events from which to choose. For event selection we used alerts/bulletins from the NEIC, EMSC and VEBSN. Example:

A change in color of the listed events means they are different events. Listings of the same color that appear together (like the two JAVA events listed above) are considered the same event. Clicking on an event link takes you to the next page.


Page 3 - Report of Networks with Responding Stations

This page gives an overview of available data by network. The reason for this is that the sheer volume of available stations can be overwhelming and clumsy to navigate. Therefore, this page allows you to limit what stations are displayed during the data selection to the networks of your choosing (example at right). The number of stations for which there is data available for each network is listed in the right-hand column. You can select ALL networks or individual networks. Once you have made your selections, click the "Proceed" button to continue.


Page 4 - Station Selection, Waveform Browsing, and Requesting Data

Page 4 will display all of the stations in the network(s) you selected on the previous page. The list of stations also includes stations for which the network(s) you selected are secondarily affiliated. If this is the case some stations might be displayed which do not appear to be from the selected network(s); this is because stations are always shown with their primary network displayed. Here is an example of a station list:

You have the option of sorting the list of stations by distance from the event (default), station code (alphabetical), or by network if more than one network was selected on the previous page. There is also a map of responding stations available for viewing (link in upper right corner).

Stations are listed as STATION_CODE.[LOCATION_CODE.]NETWORK_CODE (the location code is only displayed if it exists) with their distance and azimuth from the event listed below them. Clicking on a station name will launch a Java applet version of SeisGram2K that displays waveforms from all available channels for that station.

Clicking on the checkbox next to a station name means that you want to include that station in your final request for data. You can select ALL stations to be included; ALL stations for just selected networks; or individual stations. If you select ALL, any other boxes you have checked will be ignored. If you have selected ALL for a given network (or networks), you may still select individual stations from other networks and they will be included in your request. In the example image above, the user has selected to include all stations from the IC network and one station from the UW network in the request.

Scrolling down the screen you will see a list of available channels. This list is a compilation of all channels for all of the stations on the page. To determine what channels are available for a given station, browse the seismograms for that station and the channels are listed at the top of the browse window.

In the example above, the user has selected all of the broadband channels (B??), all of the vertical channels (??Z) and one north-south channel (SHN). For illustration, red circles have been drawn around the channels that will be included in the request based on the user's selections. If you use the wildcard options (those with ??), only seismic channels will be selected. (If you need help with channel descriptions, please review Appendix A of the SEED manual.)

At the bottom of the page we see the available output options. The default selection is SEED. (See descriptions of the output options at the end of this file.) Next, select the time window for your data request. Limits are ~5 minutes before and ~1.5 hours after the P-phase arrival, depending on the available data

Now that the data selection has been made, the user is ready to fill in personal information to uniquely identify the request.The User Name is required and used to create a personal directory in the public FTP area on the ORFEUS server. The Request Label is also required and will be used to name the data product. If you are requesting several data sets, you might want to use something more descriptive such as location or time. Both of these fields are mandatory. If you would like to be notified by email when your request has been processed, you will need to fill out the last field and click the checkbox (as shown in the example).

Click the "Process Request" button at the bottom of the screen when you are satisfied with your entries. Your data request will be submitted to the ORFEUS server for processing.


Page 5 - Request Status (or "What happens when you make a request?")

After you click the "Process Request" button, you will be shown the status of your request. There is a queue for requests in progress and you will be told where you are in the queue. In this example, the user is #1 in the process queue (first column). The number of lines in the request file are shown to give all users an idea of how big a request is. Finally, the last column shows the number of minutes the request has been in the queue.

The queue moves very quickly unless there is a process that is faltering for some reason. If there is a problem with a request, the user will be notified on screen and the request will be removed from the queue. Removing a request from the queue means that other requests can move up to be processed. Below is an example of a Request Description that appears in the status window:

You don't have to wait for your request to be processed before leaving the status window. If you want to request data from other events, simply navigate back to start (home) or go back to your chosen list of events (link at the top of page 4) to make another request. Your data will be waiting in the FTP directory for you to pick up at your leisure. The data is kept for 1 week before it is discarded.

If you watch the prompts (your screen will automatically update every 20 seconds), you'll eventually see the message above. Notice that the path to a personal data directory is listed and linked at the bottom. If you choose not to wait for this prompt, you can go to ftp://www.orfeus-eu.org/pub/wilberII/userdata/<your user name> to collect your data whenever you're ready, as long as it's within one week of the request. If you choose to be notified by email, the link will be included in the notice.


Still confused? Please contact us at and we'll be happy to help you.

Thank you for trying WILBER II!


SEED

The Standard for the Exchange of Earthquake Data (SEED) is an international standard format for the exchange of digital seismological data. SEED was designed for use by the earthquake research community, primarily for the exchange between institutions of unprocessed earth motion data. It is a format for digital data measured at one point in space and at equal intervals of time. See Chapter 1 of the SEED manual for more details.

miniSEED

The term Data Only SEED Volumes (Mini-SEED) has come to be used to identify SEED data records without any of the associated control header information. (Mini-SEED is a compact way to work with waveform data.) Data Only and Dataless SEED volumes are to a certain extent the two parts of a complete SEED volume. Only Time Span Control Headers are not included in either of these components, however Time Span Control Headers can be derived from the Data Only SEED. You need a dataless SEED volume (header information) to make a full SEED volume. See Appendix G of the SEED manual for more details.

SAC BINARY or ASCII

SAC2000 is a program to examine, analyze, and plot data. This data is stored on disk as SAC data files. Each data file contains a single data set. For seismic data this means a single data component recorded at a single seismic station. For details about SAC data files, please refer to the Lawrence Livermore National Labs Web site: http://www.llnl.gov/sac/. The only difference between SAC binary and ASCII files is the file type. The ASCII files are white space delimited.

file names look like so: 2003.185.07.20.58.3718.MN.BNI..BHE.D.SAC_ASC
(year.jday.hour.minute.seconds.sec.network.station.locationID<may be empty>.channel.qualityID.format)

  • individual files - one file for each station/channel requested, no compression
  • TAR file - all of the individual files collected in one TAR file
  • gzipped TAR file - TAR file compressed using the gzip utility
  • compressed TAR file - TAR file compressed using the UNIX compress utility

 

This file last updated: 2004-01-06 18:42 PM