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 ] [ -Dfactor ] [ -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  calculates  flowlines  using  the
       specified  stage  pole (Euler) rotations. 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 tstart and tstop are in Ma and the rest is in degrees. The
              oldest stage must be listed first. tstart (tstop) is the age  of
              the  old (young) end of the stage. 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).

       -D     Modify the sampling  interval  along  flowlines.  Default  [0.5]
              gives  approximately 2 points within each grid box. Smaller fac-
              tors gives higher resolutions at the expense of longer  process-
              ing time.

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

       -H     Input file(s) has Header record(s). Number of header records can
              be changed by editing your  .gmtdefaults4  file.  If  used,  GMT
              default  is  1  header record. Use -Hi if only input data should
              have header records [Default will write out  header  records  if
              the input data have them].

       -N     Set  the  upper  age  to  assign  seamounts whose crustal age is
              affects both].

       -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(GMTMANSECTION),   grdimage(GMTMANSECTION),  project(GMTMANSECTION),
       mapproject(GMTMANSECTION), backtracker(GMTMANSECTION),  originator(GMT-
       MANSECTION)

REFERENCES

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



GMT4.0                            1 Oct 2004         HOTSPOTTER(GMTMANSECTION)