Section 1. Preparation and Siting
1-6
MAIN MENU
Type
Q for Quick Epicenter Determinations (QED)
L for Earthquake Lists (EQLIST)
M for Geomagnetic Field Values (GEOMAG)
X to log out
Enter program option: M
Would you like information on how to run GEOMAG (Y/N)? N
Options:
1 = Field Values (D, I, H, X, Z, F)
2 = Magnetic Pole Positions
3 = Dipole Axis and Magnitude
4 = Magnetic Center
[1] : 1
Display values twice
[N]: press return
Name of field model
[USCON90]: press return
Date
[current date]:
press return
Latitude
: 42/2 N
Longitude
: 111/51/2 W
Elevation
: 4454 ft
Example of report generated by GEOMAG:
Model: USCON90
Latitude: 42/2 N
Date : 7/27/93
Longitude: 111/51/2 W
Elevation: 4454.0 ft
D
deg min
15 59.6
Annual change:
0 -6.1
Exiting:
Press "Cntrl-Z" to exit GEOMAG.
When the main menu reappears either select another option or type "X" to
log out.
If you used one of the commercial numbers, the GLDSV1> prompt will
reappear.
Type "LO" to disconnect.
Use of GEOMAG is free (except for telephone charges). If possible, please
avoid using
GEOMAG between 9 a.m. and 4 p.m., mountain time, Monday through Friday.
The declination in the example above is listed as 15 degrees and 59.6 minutes.
Expressed in degrees, this would be 15.99 degrees. As shown in Figure 1.4-1,
the declination for Utah is east, so True North for this site is 360 - 15.99, or
344 degrees. The annual change is -6.1 minutes.
