NAME
originator - Associate seamounts with hotspot point sources
SYNOPSIS
originator [infile(s)] -Estage_file -Fhs_file [ -C ] [ -Dd_km ] [
-H[nrec] ] [ -Nupper_age ] [ -S[n_hs] ] [ -T ] [ -V ] -Wmaxdist ] [ -:
] [ -bi[s][n] ]
DESCRIPTION
originator reads (longitude, latitude, height, radius, crustal_age)
records from infiles [or standard input] and uses the given Absolute
Plate Motion (APM) stage poles and the list of hotspot locations to
determine the most likely origin (hotspot) for each seamount. It does
so by calculating flowlines back in time and determining the closest
approach to all hotspots. The output consists of the input records
with four additional fields added for each of the n_hs closest
hotspots. The four fields are the hotspot id (e.g., HWI), the stage id
of the flowline segment that came closest, the pseudo-age of the
seamount, and the closest distance to the hotspot (in km). See option
-: on how to read (latitude, longitude,height, radius, crustal_ag)
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)
Seamount data file(s) to be analyzed. 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 con-
tains # will be ignored.
-F Give file with hotspot locations. This file must contain one
record for each hotspot to be considered; each record must be of
the following format:
lon lat hs_id hs_name
E.g., for Hawaii this may look like
205 20 HWI Hawaii
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 Sets the flowline sampling interval in km. [5].
-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 maximum age to extend the oldest stage back in time [no
extension].
-S Set the number of closest hotspots to report [1].
-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"].
-W Only report those seamounts whose flowlines came within maxdist
to any hotspot [Default reports all seamounts].
-: 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 find the likely (hotspot) origins of the seamounts represented by
the (x,y,z,r,tc) points in the file seamounts.d, using the DC85.d Euler
poles and the pac_hs.d list of possible hotspots, and report the 2 most
likely hotspot canditates for each seamount, run
originator seamounts.d -S2 -EDC85.d -Fpac_hs.d > origins.d
SEE ALSO
gmt(GMTMANSECTION), project(GMTMANSECTION), mapproject(GMTMANSECTION),
backtracker(GMTMANSECTION) hotspotter(GMTMANSECTION)
REFERENCES
Wessel, P., 1999, "Hotspotting" tools released, EOS Trans. AGU, 80
(29), p. 319.
VERSION DATE ORIGINATOR(GMTMANSECTION)
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