gcp {Rsac} | R Documentation |
Calculates the azimuth and back azimuth of the great-circle-path between two points (source and receiver) on a sphere.
gcp(s, e)
s |
receiver, or station. This is a list with elements lat
and lon given in degrees.
|
e |
epicenter, or source. This is a list with elements lat
and lon given in degrees.
|
a list containing the following elements:
C |
azimuth, in degrees. |
B |
back azimuth, in degrees. |
a |
arc distance, in degrees. |
lat |
latitude defining the path. |
lon |
longitude defining the path. |
Eric M. Thompson <eric.thompson@tufts.edu>
Lay, T. and T. C. Wallace, (1995) Modern Global Seismology, International geophysics series; v. 58, San Diego: Academic Press.