Manual for Seismic

7/27/2019 Manual for Seismic

http://slidepdf.com/reader/full/manual-for-seismic 1/7

1

SeisanExplorerUserGuide

Version1.0

Øyvind Natvik Department of Earth Science

University of Bergen Norway

June 2012



2

Introduction Seisan Explorer (hereafter called SE) is a new graphical user interface for SEISAN written in

C++/QT. It is supported on Windows, Linux and UNIX platforms. In its current version, itreplaces the old SEISAN graphical interface for Windows, but the intention is that SE will bethe main graphical user interface for SEISAN through which most of the current processing

by EEV and MULPLT will take place. However, remaking MULPLT requires a large effortso the current MULPLT is used for now. In the following description, it is assumed that theuser is familiar with SEISAN.

Problems Please report bugs and questions to ‘[email protected]’.

Installation Windows installation:Place all files (se.exe and .dll files) in the PRO directory, and make a shortcut to ‘se.exe’ onyour desktop. Name the shortcut ‘Seisan Explorer’.

Linux installation:SE must be compiled on Linux/UNIX platforms. Depending on your platform version, thismay not be a trivial task. You might want to ask your system administrator for help.

Prerequisits:

- SEISAN (version 9.1 only).- Qt libraries version 4.6 (or newer).- fontconfig 2.4.2 (or newer).- GCC complier collection with gfortran.- QtSDK version 2010.04 (or newer). See 'http://qt-project.org'.

Building Explorer:

The qmake program is a part of the QtSDK. You need qmake in your path. Alternatively, youcan specify full path to qmake.

- Move into the directory containing the SE source code.- Copy the SEISAN library 'seisan.a' from $SEISAN_TOP/LIB to the ‘linux’ subfolder.- Run 'qmake se.pro' to build the makefile.- Run 'make' to build the executable named 'se'.- Copy the 'se' executable to the $SEISAN_TOP/PRO folder.



3

HowSEworks SE loads S-files from a SEISAN database. Only the S-files that falls within a user specifiedtime interval are read. All information in the S-files is stored in memory for fast access. SE isdimensioned for up to one million events. In contrast to EEV, SE can read in data for several

months or years, thereby giving the user the opportunity to work with large datasets withoutany artificial time boundaries. A subset of the data in each S-file is displayed in rows in theEvent List view as demonstrated on the front page and in Figure 2.

When a database has been loaded, the user can select one or several events for further action,a bit like EEV. The Event List view columns can to a certain degree be customized(View/Select Columns). A Log view is available where most system messages are shown.

AnoverviewoftheSEapplication. The application can present two views, the Event List view and the Log view. The Event Listview is shown in the figure below. The program also has a title bar at the top and a status bar at the bottom. The title bar shows the currently opened database and the number of eventsloaded.

Figure 1. Basic Event List view with status bars.

The left part of the status bar shows messages. Status bar messages will only be displayed for a few seconds and then disappear since they might soon be replaces by another message. Theright part of the status bar shows permanent information which is the current time interval and

the current operator code.



4

TheEventListview When a database is loaded into SE, the Event List view will be populated (see Figure 1), andthe first event will automatically be selected. To navigate, use arrow keys or the scroll bars.Click on an event to select it. Several events can be selected as needed using standard

selection procedures.

Figure 2. The Event List view.

In the Event List view you can:

• Perform actions with selected events.

• Search for an event by time: From Event List view, just start typing the desired date(type as yyyymmddhhmmss), and the event nearest in time will be the selected. Press‘Enter’ when finished searching.

• Navigate to a particular row number by typing ‘0’ followed by the row number (whatin EEV was called event number) and press ‘Enter’.

• Navigate between selected events using the commands ‘n’ (next), and ‘shift+n’

(previous).• Search event(s) by time association: Use shortcut ‘a’ and all events associated with

each other within given time window (default 200 seconds) are selected.

Executing actions.Right-click inside the Event List view to bring up the Event List menu. The menu shows allavailable actions and their corresponding shortcuts. The current actions are:

• Associate events (a): Find events occurring within a given time interval (default 200s).

• Copy (c): Copy highlighted events to file ‘copy.out’ (located in work directory).

• Delete (d): Delete the selected S-files.

• Duplicate (shift+d): Duplicate an event file.• Edit comment lines (shift+c): Edit comment lines in S-file.



5

• Edit with text editor (e): Edit the S-file.

• EEV (<): Launch EEV with current event. Some EEV commands will be disabled.

• Locate (l): Locate current event with HYP. A change from EEV is that the user will begiven the option of updating the event in which case the S-file is overwritten.

• Merge (m): Merge one or more events into a destination event. Note: To mark events

for merging, first mark the destination event. Then mark one or more events whileholding down the ‘Ctrl’ key.

• Plot with mulplt (p): MULPLT is started in ‘all default’ mode so no questions areasked. Results of picks are put back in S-file and SE.

• Register (r): Register event.

• Set distance indicator (r): Changes the distance indicator in SE and the S-file

• Show with Google Earth (G): Creates a KML file to be used with GE.

Other actions:

• Refresh view (F5): Refreshes the current Event List view. Does not reload thedatabase.

• Load event file into Explorer (F4): Reads a single S-file into SE. The S-file must belong to the currently opened database, but it can be outside of the current timeinterval.

• Unload event from Explorer (F3): Unloads an event from SE. This action does notremove the event from the SEISAN database.

Note that many actions are disabled while SE is busy loading a database.

Sorting data in the Event List view.

The default sorting is by date/time. However, the displayed data can also be sorted by thecontents of any other column. Simply click on the header of any column and all eventsdisplayed are in the order of the clicked column. The order can also be reversed by clickingthe header again. E.g. clicking twice on the depth column will order events by increasingdepth.



6

TheLogview. The Log view (Figure 3) shows all important messages from SE. Information messages are

black, warnings are blue, and errors are in red colour. Every time an error occurs, it will belogged here, and SE will automatically switch to the Log view to make the user aware of the

error. The log view has a menu that can be activated by right-clicking anywhere in the view.

Figure 3. The Log view.

The menu has commands for common tasks such as clearing the view, or saving it to a file. If the Log view holds lines with errors/warnings for S-files, then it is possible to edit these S-files directly from the log view by right-clicking the line.

Theworkdirectory. SE will always use a specific work directory where the log file and all output is written, e.g.from hypocenter locations. This work directory is independent from where SE is started,

whether from the desktop or a particular directory. The work directory is by default WOR, butan alternative directory can be set (File/Configure). The work directory is also the localdirectory where MULPLT will look for waveform files irrespective of from which directorySE has been started. The current work directory is shown in the Log view when SE is started.

Multiple running copies of SE should not share the same work directory. Therefore - when SEstarts up - it will look for the existence of a lock file called ‘se-workdir.lock’ in its work directory. If it does not exist, then it will be created to signal that directory is now in use. If itexists, then this may indicate that another user is currently using the work directory. In thiscase a dialog box with a warning appears (see Figure 4).



7

Figure 4. Warning (work directory may be in use).

The user will be allowed to remove the lock file (if he is sure that none else is actually usingthe work directory), or continue to select a new work directory. Any lock file created by SEwill automatically be deleted when the program is closed. If SE should crash, then the lock file will be left in the work directory. In this case it can safely be removed manually.

Openadatabase. Databases are opened under File/Open where the choices are the usual: ‘Default Database’(as set by DEF_BASE), ‘Local Database’, ‘Index File’ or ‘Database’. The last option willopen a dialog box showing the REA directory with all databases (standard 5 letter directories),and one can be selected. A new option - compared to EEV - is that a database (the year monthstructure) can be located under any directory, not just REA. It can be selected by navigatingthe file system from the dialog box. This arbitrary structure must have correspondingwaveform files in WAV, SE working directory or a named directory (see SEISAN.DEF) andcannot use the WAV structure since it is not placed in a standard REA structure.

SE can be configured to automatically open the last used database on start-up (seeFile/Configure).

Setting a time interval.

When a database is being opened, SE will suggest a default time interval. The default timeinterval has an ‘End date’ equal to the current date, and the ‘Start date’ is set to the currentdate minus 30 days (this value is user configurable). Both start-date and end-date can bemodified by the user (see Figure 5). The default time span between start-date and end-date

can be set under File/Configure. The time interval can bechanged at any time by pressing ctrl-t or using the mainmenu (File/Set Time Interval). If the time interval ischanged when a database is open, then the user will be

prompted to reload the database.

Figure 5. Set time interval.

Documents

Manual for Seismic