NAME
xm_well - Well format for the xmap8 program
SYNOPSIS
xm_well - Input File Format
DESCRIPTION
Wells are simple lists of 3D lines in space. Actually
"well" is a misnomer: you can plot any 3D line using this
option of xmap8. I use this to plot 3D vectors. There is
an extended format that allows you to also plot lithology
and dip alon the well.
Format:
id = well ident
# = number of points in well
style = 0,1,2,3 see below default is 0 for simple well.
color = color for plotting (1-20)
lat = degrees
lon = degrees positive east
depth = km, positive downward
id # flag color
lat lon depth
.
.
.
example:
32-20 68 0 11
36.011303 -117.792274 -0.087500
36.011303 -117.792267 -0.027500
36.011303 -117.792259 0.052500
36.011295 -117.792259 0.082500
36.011292 -117.792259 0.132500
36.011292 -117.792259 0.162500
.
.
.etc....
Here is the extended format for the wells:
lat lon depth dip strike length lithology
For example:
23-17 107 3 2
36.022938 -117.795868 -0.127500 45.000000 20.000000 0.200000 2
36.022938 -117.795868 -0.087500 45.000000 20.000000 0.200000 2
36.022942 -117.795860 -0.037500 45.000000 20.000000 0.200000 2
36.022942 -117.795868 -0.017500 45.000000 20.000000 0.200000 2
36.022942 -117.795868 0.002500 45.000000 20.000000 0.200000 2
36.022942 -117.795876 0.052500 45.000000 20.000000 0.200000 2
36.022942 -117.795883 0.082500 45.000000 40.000000 0.200000 4
LAT LON Z AZIM (deg) DIP Length Lithology
the first line includes:
name #_of_points style color
where,
name= 8 character identifier
#_of_points = total number of points for that well
You may have numerous wells per file
style = 0 = simple well (lat lon z)
1 = well with lithology (lat lon z lith)
2 = well with dip meter only (lat lon z strike dip length)
3 = well with dip and lith (lat lon z strike dip length lith)
color = one of the 28 available colors from the palette.
There are thus 4 styles one can use to insert well information at this point.
I may expand this at a later date to include well log information plotted as a
time series along the well.
---------------- 3D ARROWS ------------------
I have written a program to convert focal mechanism P-axes into little
3D arrows - which I then rotate using spin.
All you have to do is make a "well" file which has the
lat-lon-depth of the positions you want plotted
as vectors. Here is an example arrow plotting a P-axis direction
in Western Washington: (there are 3 "wells" here)
paxis 5 0 5
47.186123 -122.539413 3.900000
47.172630 -122.550819 2.900000
47.179489 -122.543701 3.437500
47.180271 -122.545677 3.437500
47.172630 -122.550819 2.900000
paxis 5 0 6
47.186123 -122.486626 5.200000
47.172630 -122.475220 4.200000
47.180271 -122.480354 4.737500
47.179489 -122.482338 4.737500
47.172630 -122.475220 4.200000
paxis 5 0 7
47.217281 -122.460205 6.500000
47.217281 -122.437340 5.500000
47.218060 -122.449631 6.037500
47.216503 -122.449631 6.037500
47.217281 -122.437340 5.500000
The arrows consist of 5 points in this order:
(tail, head, UP_point, DN_point, head)
UP
\
\
Tail-------------------------Head
/
/
DN
The points must be inthe correct order to plot so it looks like
an arrow. You could make a simpler plot with just 2 lines
or even just one line if you are not concerned with
directionality.
I create these arrows by first drawing them in 2D and then
rotating them and translating them to their correct
position and orientation. (that is the programming you may have to do.
you can modify my program for plotting P-axes if you like)
When running xmap8 you will see a well symbol plotted
at the location of the first element in the well (the Tail)
if you select "Project Wells" you will see the horizontal projections.
When you make cross sections you will see the wells in 3D.
Wells can be imported into the spin module, but
if you have a ton of them, spnnning will be slow, of course.
The spin module allows you to plot the wells in any 3D view angle.
SEE ALSO
xmap8
xm_color
xm_hypo
xm_map
xm_menu
xm_origin
xm_points
xm_raster
xm_station
xm_well
xm_wire
xm_xsec
xm_ellipse
REFERENCES see article by J. M. Lees: Lees, J. M. (1995) Xmap8: Three-dimensional GIS for geology and geophysics, Seismological Research Letters: 66, 33-37.
Prof. Jonathan M. Lees
Yale Geology Dept.
P.O. Box 208109
New Haven, CT 06520-8109
(203)432-6947
lees@love.geology.yale.edu