xm_map


NAME

xm_map - Map format for the Geotouch program

SYNOPSIS

xm_map - Input File Format

DESCRIPTION

Maps in Geotouch come in 3 formats: default (dumb map) gmt_style (dumb map) lees_format (smart format) A "smart format" map is one that has various attributes that allow the user to control plotting or processing. lees_format maps include information about whether they are point, line or fill objects, color for plotting and an ascii code for determining the kind of object (river, thrust fault or high- way?). The program works best when using lees_format maps and they recommended. If you use lees-format maps you can have numerous entries on the command line.


FORMAT

Default map Format is an ASCII file with alist of strokes:
Lat1 Lon1 Lat2 Lon2
(which represents a stroke in lat-lon)

-------------------------------------------------------------
GEOLOGICAL MAP FORMAT

Identification number_of_points Style Color kind minlat maxlat minlon maxlon

Identification = 8 character id the first 4 chars are used for
the geological formation name

number_of_points = number of lat-lon pairs associated with this id

Style = style of object:
1 = point (then number_of_points must be 1)
2 = line
3 = filled object (geological unit)

Color = use this number from 1-20 for different color formations
color(0) = black
color(1) = white
color(others) = various colors
Kind

-----------------------------------------------------
to get GMT maps you must use the -J option and not the -M option
GMT style:
each stroke is a list of lat-lons.
separated by the ">" character"
> first stroke
lon1 lat1
lon2 lat2
lon3 lat3....etc
> second stroke ....etc

---------------
NOTE: By default GMT uses lon-lat instead of lat lon. This conventions is followed here. If the first line in the file contains the string "latlon", however, the entries are switched to lat-lon (the standard lees convention)
or:
If you set the environment variable:
setenv XMA_LONLAT 1
this will switch reading of lat-lon to lon-lat
or:
Another way is to simply transfer the GMT map file to Geotouch mapfile.
See utilities on the ftp site for doing this.
NOTE: GMT can read in any Geotouch map files.

-----------------------------
lees_format Geologic maps:
This is the same as GMT format accept:
LAT LON is the default, and the first line contains the information
for the 3D GIS data base:


> strokename num type color code lat1 lat2 lon1 lon2

NOTE: the ">" must be in the first line of each stroke by convention
num = number of points in stroke
type = 1 = points
2 = line
3 = fill object
color = color to plot - see documentation on color selection
code = ascii character (0-9, a-z, A-Z) describing object.
This is a convention chosen by the users.
Presently I use these codes:

a = major coasts islands lakes
b = intermediate coasts islands lakes
c = minor coasts islands lakes
d = very minor coasts islands lakes
e = major rivers
f = intermediate rivers
g = minor rivers
h = very minor rivers
i = political borders
j = major faults
k = minor faults
l = geology formation
m = major high ways
n = minor roads
p = plates

0 = generic


(when running Geotouch a plotting code may be supplied to select
off those parts of the geologic maps one needs)

lat1 lat2 lon1 lon2 = min-max bounds on the stroke. (this is
important for selections from large data-bases)


Example:


> CPLS0001 125 3 1 0 34.1767 34.3752 -116.967 -116.560
34.0000 -116.000



SEE ALSO


Geotouch
xm_color
xm_hypo
xm_map
xm_menu
xm_origin
xm_points
xm_raster
xm_station
xm_well
xm_wire
xm_xsec
xm_ellipse
xm_legend


  • Geotouch:
    Three-dimensional GIS for Geology and Geophysics.



  • REFERENCES


    see article by J. M. Lees:


    Lees, J. M. (1995)
    Geotouch: Three-dimensional GIS for geology and geophysics,
    Seismological Research Letters: 66, 33-37.





    Address:


      
    Prof. Jonathan M. Lees Department of Geological Sciences CB #3315, Mitchell Hall University of North Carolina Chapel Hill, NC 27599-3315 (919) 962-0678 FAX (919) 966-4519 leesj@email.unc.edu