anchor.diff:  !----------------------------------------------------------------------!
   
         SUBROUTINE wellscopp(mom,mag)
  +! Wells, D.L., Coppersmith, K.J. (1994). New empirical relationships
  +! among magnitude, rupture length, rupture width, rupture area, and
  +! surface displacement. Bulletin of the Seismological Society of America
  +! 84, 974-1002.
         IMPLICIT none
         REAL*8 mom,mag,a(4),b(4),surlen,totlen,width,area,maxslp,avgslp
         CHARACTER*3 typ(4)
  
positive.code: !      write(0,*)
  !     1 '                       HANKSBAKUN (Hanks and Bakun, 2008)'
        write(0,*)
       1 '                       BLASERETAL (Blaser et al., 2010): ',
       2                         'global subduction zone events (Mw 4.8-',
       3                         '9.5)'
        write(0,*)
       1 '                       STRASSERETAL (Strasser et al., 2010): ',
       2                         'global subduction zone events (Mw 6.0-',
       3                         '9.5)'
        write(0,*)
       1 '                       YENMA (Yen and Ma, 2011): collision ',
       2                         'zone (Taiwan) events (Mw 4.6-8.9)'
  !      write(0,*)
  !     1 '                       STIRLINGETAL (Stirling et al., 2013)'
        write(0,*)
       1 '                       HAYES (Hayes, 2017): global finite ',
       2                         'fault models of Mw 7.5-9.2 events'
        STOP
        END
  
negative.code:       write(*,1007)
        do 105 i = 1,4
            maxslp = 10**(a(i)+b(i)*mag)
            write(*,1008) typ(i),maxslp
    105 continue
        ! Average slip
        a(1) = -6.32d0  ! 0.61
  