John Seach, Volcano Live

 Volcano Inflation - John Seach

Inflation begins as magma rises into the summit reservoir. Tiltmeters measure changes in slope of the ground. The Global Positioning System (GPS) is used to measure the position of benchmarks. In order to determine the deformation caused by an episode of inflation, scientists must install and survey the benchmarks and install tiltmeters and GPS receivers (if continuous measurements are desired) before magma moves.
As the magma reservoir becomes inflated, the ground around it cracks to accommodate its increasing volume. Many small earthquakes occur in the area surrounding the magma as the rocks break. As the surface of the volcano changes shape, tiltmeters record tiny changes in slope, distances increase between benchmarks on opposite sides of the caldera, and elevations of the stations increase.


Volcano Inflation