Changes to the surface of a volcano that occur due to magma movement underneath the surface. Most volcano deformation can only be detected and measured with precise surveying techniques such as with a Global Positioning System (GPS), tiltmeter, Interferometric Synthetic Aperture Radar (InSAR), or an Electronic Distance Meter (EDM).

A
B
C
D
E

F
G
H
I
K
L
M
O
P

Q
R
S
T
U
V