HOTSPOTTER(l)

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 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 Amplitude 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 registration].

-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)]. Applies to geographic coordinates only.

-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.