A
1 kPa
(10 cm H2O)
1024
1025
1027
857
Events per hour
80
70
60
50
40
30
20
10
0
7 June 1999
12 June 1999
17 June 1999
Time (days)
Earthquakes per day
B
140
120
100
80
60
40
20
0
1027
0.1 kPa
(1 cm H2O)
0
50
Days from 8 June 1999
VOLCANO DEFORMATION–
Geodetic Monitoring Techniques
By Daniel Dzurisin
U.S. Geological Survey graphics
100