23.3.2 Explanations of output

Minimum number of polarity misfits overall: Minimum number of wrong polarities for anyone of the grid points disregarding amplitude fit. This is the number of polarity errors to find a solution without amplitudes.
Minimum average amplitude error overall: The minimum average log error for any grid point disregarding errors in polarity.
New number of pol. misfits inc. extra is: The new limit for polarity errors.
New average amp limit inc. extra: Based on the above, a new amplitude ratio error limit is set.
Minimum average amplitude error for pol ok: The new error limit considering polarities within limit.
New average amp limit is: In order to get sufficient solutions, the amplitude error limit is increased to this value.

Output files: Hash_seisan.out: A summary of the solutions(s).
Fps.out: The solution(s) in SEISAN format.

Storing and selecting fault plane solutions: Format errors estimates and quality.

The fault plane solutions are stored in the S-file. Different programs give somewhat different parameters and sometimes the same output field is used for different parameters. Some programs give strike of dip instead of strike of fault plane, but values used in SEISAN are converted to strike of fault plane. Each program is indicated with its own name like "HASH F" at the end of the F-line. If no characters are written in the blank space, any new solution will overwrite the old one. However if anything is written like "HASH 1F", any new solution will create a new line in S-file. This is also the case if a quality indicator is written (see below). An example is:

     158.0      53.1    -156.4  7.0  3.8      0.30 0.57 0.76      FCF HASH     F
   39.2900   66.3900  -63.6500                          0.13  2 1 FCF FOCMEC   F
      42.0      68.0     -62.0  7.0  5.0  3.0  0.1  0.2           FCF FPFIT  A F
      18.7      67.8     -63.3                                4   FCF PINV     F

In this example, there are 4 solutions made by the 4 programs and the solution made by FPFIT has been selected as a prime solution with quality A. The content and format is:

Type F Line (Optional): Fault plane solution 

Columns Format Description

  1:30 3F10.0 Strike, dip and rake, Aki convention
 31:45 4F5.1  Error in strike dip and rake (HASH), error in fault plane and aux. plane (FPFIT) 
 46:50 F5.1   Fit error:  FPFIT and HASH (F-fit)
 51:55 F5.1   Station distribution ratio (FPFIT, HASH)
 56:60 F5.1   Amplitude ratio fit (HASH, FOCMEC)
 61:62 I2     Number of bad polarities (FOCMEC, PINV) 
 64.65 I2     Number of bad amplitude  ratios (FOCMEC)
 67:69 A3     Agency code
 71:77 A7     Program used
 78:78 A1     Quality of solution, A (best), B C or D (worst), added manually
 79:79 A1     Blank, can be used by user
 80:80 A1     F

Quality indicator: The indicator can be any character, but usually A to F is used with A as the best. It is up to the user to manually assign a quality indicator. Events can later be selected based on quality indicator. Programs SELECT and FOC use quality indicators. The quality indicator as well as the selection of the prime solution can be select by command fq in eev. An example is given below:

Fault plane solutions for this event 1 180.3 55.1 -123.7 5.0 4.4 0.04 0.67 0.38 SJA HASH A 2 6.1000 48.4400 -48.0700 2 SJA FOCMEC 3 191.0 51.0 -110.0 SJA DREGER 4 185.0 48.0 -121.0 HRV CMT A Give fps number to be prime solution, enter for no change

Peter Voss : Tue Jun 8 13:38:42 UTC 2021