1ORIGINATOR(1) Generic Mapping Tools ORIGINATOR(1)
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6 originator - Associate seamounts with hotspot point sources
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9 originator [infile(s)] -Estage_file -Fhs_file [ -C ] [ -Dd_km ] [
10 -H[i][nrec] ] [ -L[flag ] [ -Nupper_age ] [ -Qr/t ] [ -S[n_hs] ] [ -T ]
11 [ -V ] -Wmaxdist ] [ -:[i|o] ] [ -bi[s|S|d|D[ncol]|c[var1/...]] ]
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14 originator reads (longitude, latitude, height, radius, crustal_age)
15 records from infiles [or standard input] and uses the given Absolute
16 Plate Motion (APM) stage poles and the list of hotspot locations to
17 determine the most likely origin (hotspot) for each seamount. It does
18 so by calculating flowlines back in time and determining the closest
19 approach to all hotspots. The output consists of the input records
20 with four additional fields added for each of the n_hs closest
21 hotspots. The four fields are the hotspot id (e.g., HWI), the stage id
22 of the flowline segment that came closest, the pseudo-age of the
23 seamount, and the closest distance to the hotspot (in km). See option
24 -: on how to read (latitude, longitude,height, radius, crustal_ag)
25 files.
26 No space between the option flag and the associated arguments.
27 Use upper case for the option flags and lower case for modifiers.
28 infile(s)
30 Seamount data file(s) to be analyzed. If not given, standard
31 input is read.
32 -E Give file with stage poles and opening angles. This file must
34 contain one record for each stage; each record must be of the
35 following format:
36 lon lat tstart tstop ccw-angle
38 where tstart and tstop are in Ma and the rest is in degrees.
40 The oldest stage must be listed first. tstart (tstop) is the
41 age of the old (young) end of the stage. Blank lines and
42 records whose first column contains # will be ignored.
43 -F Give file with hotspot locations. This file must contain one
45 record for each hotspot to be considered; each record must be of
46 the following format:
47 lon lat hs_id hs_name
49 E.g., for Hawaii this may look like
51 205 20 HWI Hawaii
53 Blank lines and records whose first column contains # will be
55 ignored.
56
58 -C Expect Total Reconstruction Poles rather than Backward Stage
59 Poles [Default]. File format is similar to the stage pole for‐
60 mat except the youngest rotation must be listed first and that
61 the tstart column is optional (assumed to be 0 Ma).
62 -D Sets the flowline sampling interval in km. [Default is 5].
64 -H Input file(s) has Header record(s). Number of header records
66 can be changed by editing your .gmtdefaults4 file. If used, GMT
67 default is 1 header record. Use -Hi if only input data should
68 have header records [Default will write out header records if
69 the input data have them]. Blank lines and lines starting with #
70 are always skipped.
71 -L Output clostest approach for nearest hotspot only (ignores -S).
73 Choose -Lt for (time, dist, z) [Default], -Lw for (omega, dist,
74 z), and -Ll for (lon, lat, time, dist, z). Normally, dist is in
75 km; use upper case modifiers TWL to get dist in spherical
76 degrees.
77 -N Set the maximum age to extend the oldest stage back in time [no
79 extension].
80 -Q
82 INput files only has (x,y,z); specify constant values for r,t that
84 will be implied for each record. -S Set the number of closest
85 hotspots to report [Default is 1].
86 -T Truncate seamount ages exceeding the upper age set with -N [no
88 truncation].
89 -V Selects verbose mode, which will send progress reports to stderr
91 [Default runs "silently"].
92 -W Only report those seamounts whose flowlines came within maxdist
94 to any hotspot [Default reports all seamounts].
95 -: Toggles between (longitude,latitude) and (latitude,longitude)
97 input and/or output. [Default is (longitude,latitude)]. Append
98 i to select input only or o to select output only. [Default
99 affects both].
100 -bi Selects binary input. Append s for single precision [Default is
102 d (double)]. Uppercase S or D will force byte-swapping.
103 Optionally, append ncol, the number of columns in your binary
104 input file if it exceeds the columns needed by the program. Or
105 append c if the input file is netCDF. Optionally, append
106 var1/var2/... to specify the variables to be read. [Default is
107 5 input columns].
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110 To find the likely (hotspot) origins of the seamounts represented by
111 the (x,y,z,r,tc) points in the file seamounts.d, using the DC85.d Euler
112 poles and the pac_hs.d list of possible hotspots, and report the 2 most
113 likely hotspot candidates for each seamount, run
114 originator seamounts.d -S2 -EDC85.d -Fpac_hs.d > origins.d
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119 GMT(1), project(1), mapproject(1), backtracker(1) hotspotter(1)
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122 Wessel, P., 1999, "Hotspotting" tools released, EOS Trans. AGU, 80
123 (29), p. 319.
124GMT 4.3.1 15 May 2008 ORIGINATOR(1)