11.1.1 Input parameters for SELECT

In the input database (or file) a time window must always be given. If no more selection is done, all data in time window is selected. Further selection can be done by choosing a number and giving parameters. The chosen parameters are then shown on the next parameter selection menu as shown above for magnitude. Parameters can be reentered. Parameters not entered will have no influence in the selection. If several parameters (numbered selections below) are entered, conditions for all must be true for the event to be selected. Within each numbered selection, usually only one of the entered conditions must be fulfilled for the event to be selected. If e.g. Ml and Mb are selected, events, which have either magnitude, will be selected. When no more parameters are desired, press enter.

  1. - Fault Plane Solution
    Selects events with a fault plane solution (F- line in S-file). There will also be the question: "Give quality, e.g. A or ABC, enter for all", in this way different qualities can be selected.
  2. - Earthquake Felt
    Events felt indicated by a type 2 line
  3. - Magnitude Type(s)
    Normally, all magnitudes for one event are searched to see if any magnitude fits the selection criteria. With option 3 it is possible to use one or a combination of magnitude types e.g. L and B. If magnitudes without type are to be selected, use underscore “_” for magnitude type. If there is no magnitude in the first magnitude position, chose “N” for one of the magnitude types to be able to select the other 2 magnitudes on the line. Magnitude types are: C: Coda magnitude, L: Local magnitude, b: mb, B: mB, s: Ms, S: MB and W: Moment magnitude. N: Find events with no magnitude in first position. An event is selected if any one of the types of magntudes are found. Magnitudes are only searched on first header line unless “Use all header lines is set”.
  4. - Distance ID(s)
    Restricting the search to be for one or a combination of the distance id's L, R and D.
  5. - Event ID(s)
    Restricting the search to one or a combination of event id's, e.g. E and V for explosion and volcanic events. The letters used for selection are not limited to the examples shown above, they are however the ones used currently. It is thus e.g. possibly to label events as X for unknown type (column 23 in header line) and then later on select out all those events by specifying X for event ID. For the 3 questions about types, up to 5 letters can be used. The currently most used codes are: B: Blank (no ID), E: Explosion, P: Probable explosion, V: Volcanic, S: Sonic boom, Q: Earthquakes. For a full list, see the Nordic format in Appendix. If no selection is given, all events are selected. If e.g. Q is used as input, only events with Q ID are selected. If B is selected, only events with no ID are selected. So if all earthquakes and volcanic events are to be selected, use QV. Without the Q, only volcanic events are selected. In most cases no ID is also earthquakes, but they have not been marded as so. In this case, in order to get all earthquakes, use BQ. Selection is made if either one of criteria is met.

    Note: Before october, 2018, using Q was equivalent to using BQ and there was no possibility to select Q or no ID only.

  6. - Magnitude Limits
    Range of magnitudes to select. Note that if no magnitude type is given, the extreme of all magnitude types reported is used. Magnitudes are only searched on first header line unless Üse all header lines is set.̈
  7. - Latitude Limits
    Range of latitude. NOTE: If no latitude or longitude values are chosen, SELECT will include an event even when it is not located if the remaining criteria are OK. If it is required that only located events are searched for, enter at least one value like an upper latitude limit of 95. If ONLY events with no locations are wanted, enter 99 as lower latitude limit. This option is intended to find all events not located in a file or data base.
  8. - Longitude Limits
    Range of longitude.
  9. - Depth Limits
    Range of depths.
  10. - RMS Limits
    Range of rms travel time residuals.
  11. - Number of Stations Limits
    Range of number of stations. This option can be combined with option CODAQ to seach for a number of stations in a given distance range.
  12. - Hypocenter Errors Latitude Limits
    Range of hypocenter latitude errors. Works only if error line (E-type) is present in S-file. Currently error lines are generated by HYP and the ISC conversion program ISCNOR. There should only be one error line in file associated with the prime solution in first header line. However, if more than one error line is present, all are checked and if one fulfills the selection criteria, the event can be selected.
  13. - Hypocenter Errors Longitude Limits, See 12.
  14. - Hypocenter Errors Depth Limits, See 12.
  15. - Minimum Number of Polarities, only P-phases are used
    Counts all polarities, useful to find potential events for fault plane solutions.
  16. - Hypocenter Agencies
    Selects events only with given hypocenter agencies as indicated on header line.
  17. - Magnitude Agencies
    Select only events with given magnitude agencies as indicated on header line. Magnitudes are only searched on first header line unless Üse all header lines is set.̈
  18. - Station Codes, components, distance range and phase
    Selects only events with given stations, component, distance range and phase. A formatted help line comes up for selecting items. Any one or a combination can be selected, however, a station code or component code must be selected. The phase can be 8 characters long. The distance can be hypocentral or epicentral. Distances are integers right justified.

  19. - Polygon
    Selects events within a given polygon of at least 3 latitude-longitude pairs.
  20. - Use all header lines
    All header lines are searched for relevant information
  21. Search for text string in S-file
    Search the database for any text string in any line of the S-file. The search is normally case sensitive, but if the search string is terminated with 'case' like 'bergencase', then the search is case independent. The search string can be 80 chars long plus 4 if termniated with 'case'. It is thus possible to make a seach including the line type in character 80.
  22. - Gap range
    The range of gap as given on the E-line (normally 2. header line). Only hypocenters calculated with SEISAN version 7.0 have gap.
  23. - Phase
    Look for events with particular phases. Up to 6, 8 character phase names can be selected. The event is selected if at least one of the phases is present for the event. For a more selective selection based on phase, see option 18.
  24. - Volcanic subclasses
    Search for events of given subclasses given by up to 10 codes. Any code can be given, however, normally they will be as defined in VOLCANO.DEF. The program searches for lines starting with `VOLC MAIN'.
  25. - Moment tensor solution
    Search for events with a moment tensor solution as indicated by M-lines.