c      subroutine msmag(t,amp,msflg,ms,depth,delta)
c
c   Msmag returns an MS station magnitude, ms, for a reading with
c   period t (s), amplitude amp (um), and flag msflg from an event at
c   depth depth (km), and distance delta (deg).  Note that the bsdist
c   table (for distances over 160 deg) was taken for QQUAKE.
c
c     character*1 msflg

      real ms
      dimension bsdist(50)
c TABLE CONTAINING Bs VALUES TO COMPUTE MS MAG AT DISTANCES
c OVER 130 DEGREES.
      data bsdist/  3.49,3.5,3.5,3.5,3.51,3.51,3.51,3.51,3.52,3.52,
     1 3.52,3.52,3.52,3.53,3.53,3.53,3.53,3.53,3.54,3.54,3.54,3.54,
     2 3.54,3.54,3.54,3.54,3.54,3.54,3.54,3.54,3.54,3.53,3.53,3.53,
     3 3.52,3.52,3.52,3.52,3.51,3.51,3.51,3.50,3.49,3.47,3.44,3.41,
     4 3.39,3.34,3.29,3.19/
c
        do i  = 1, 50
          print *, bsdist(i)
        enddo

1       print *, ' Input the amplitude, period, and distance'
        read *, amp, t, delta
        if(amp.eq.0) then
          print *, 'amplitude may not be zero.'
          stop
        else if(delta .lt. 20. .or. delta .gt. 180.) then
          print *, 'distance must be between 20 and 180 degrees,',
     *      ' inclusive.'
          stop
        else if(t.le.9..or.t.gt.99.) then
          print *,
     *      'period must be greater than 9 and ',
     *      'less than or equal 99 seconds.'
          stop
        else if(delta.le.130.) then
          ms=alog10(amp/t)+1.66*alog10(delta)+3.3
        else
          ms=alog10(amp/t)+bsdist(int(delta-129.5))+3.3
        endif

        print *, ' Ms = ', ms
        goto 1
c     if((t.lt.18..or.t.gt.22..or.delta.gt.160.).and.msflg.ne.'R')
c     1 msflg='r'
c      return
c
 10   ms=0.
      msflg='n'
      return
      end