NAME

     hotspotter - Create CVA image from seamount flowlines


SYNOPSIS

     hotspotter      [infile(s)]      -Estage_file      -GCVAgrid
     -Ix_inc[m|c][/y_inc[m|c]]  -Rwest/east/south/north[r] [ -C ]
     [ -F ] [ -H[nrec] ] [ -Nupper_age ] [ -T ] [ -V ] [ -:  ]  [
     -bi[s][n] ]


DESCRIPTION

     hotspotter reads (longitude,  latitude,  amplitude,  radius,
     age)  records  from  infiles  [or standard input] and calcu-
     lates flowlines using the specified stage pole (Euler) rota-
     tions.   These flowlines are convolved with the shape of the
     seamount (using a Gaussian shape given amplitude and  radius
     =  6 sigma) and added up to give a Cumulative Volcano Ampli-
     tude  grid  (CVA).   See  option   -:   on   how   to   read
     (latitude,longitude,...) files.
          No space between the option  flag  and  the  associated
     arguments.   Use  upper  case for the option flags and lower
     case for modifiers.

     infile(s)
          Data file(s) to be processed.  If not  given,  standard
          input is read.

     -E   Give file with stage poles and  opening  angles.   This
          file  must  contain  one  record  for  each stage; each
          record must be of the following format:

               lon lat tstart tstop ccw-angle

          where time is in Ma and the rest is in degrees.  Oldest
          stage  must  be  listed first.  tstart is the time when
          the stage begins (oldest age).  Blank lines and records
          whose first column contains # will be ignored.


OPTIONS

     -C   Expect Total Reconstruction Poles (Finite Poles) rather
          than  Backward  Stage  Poles  [Default]  File format is
          similar to the stage pole format  except  the  youngest
          rotation  must  be  listed  first  and  that the tstart
          column is optional (assumed to be 0 Ma).

     -F   Force pixel registration  [Default  is  grid  registra-
          tion].

     -H   Input file(s) has Header record(s).  Number  of  header
          records  can  be  changed  by editing your .gmtdefaults
          file.  If used, GMT default is 1 header record.

     -N   Set the upper age to assign seamounts whose crustal age
          is unknown (i.e. NaN) [no upper age].

     -T   Truncate seamount ages exceeding the upper age set with
          -N [no truncation].

     -V   Selects verbose mode, which will send progress  reports
          to stderr [Default runs "silently"].

     -:   Toggles      between      (longitude,latitude)      and
          (latitude,longitude)    input/output.     [Default   is
          (longitude,latitude)].

     -bi  Selects binary input.  Append s  for  single  precision
          [Default  is  double].   Append  n  for  the  number of
          columns in the binary file(s).   [Default  is  5  input
          columns]


EXAMPLES

     To create a CVA image from the Pacific (x,y,z,r,t)  data  in
     the file seamounts.d, using the DC85.d Euler poles, run

     hotspotter seamounts.d -EDC85.d  -GCVA.grd  -R130/260/-66/60
     -I10m -N145 -T -V

     This file can then be plotted with grdimage.


SEE ALSO

     gmt(l),     grdimage(l),     project(l),      mapproject(l),
     backtracker(l) originator(l)


REFERENCES

     Wessel, P., 1999, "Hotspotting" tools released,  EOS  Trans.
     AGU, 80 (29), p. 319.