Dike Propagation to a
Surface Load
picture 1: Mt. Etna eruption (Vers un Sens de la Vie, 2004)
Jonathan Morgan
Abstract:
Dikes are magma intrusions that have propagated through the Earth's crust from a magma chamber in the lower crust. They move by stressing the rock in front of it until it fractures and the magma then moves forward into the new fracture. Dikes are the way magma moves to a volcano from the magma chamber for an eruption. Magma propagates to a volcanic mountain because dikes propagate to the maximum compressive stress, which is the stress directed down from the weight of the volcano on Earth. This means magma from magma chambers that are not located directly underneath the volcano can erupt through the volcano. There is a point where the affect of the load from the volcano no longer affects the dikes and the dike will either propagate straight up or to another volcanic load. This is an important topic to study because some day knowing as much as we can about volcanoes could save lives.
Dikes are magma intrusions that have propagated through the Earth's crust from a magma chamber in the lower crust. They move by stressing the rock in front of it until it fractures and the magma then moves forward into the new fracture. Dikes are the way magma moves to a volcano from the magma chamber for an eruption. Magma propagates to a volcanic mountain because dikes propagate to the maximum compressive stress, which is the stress directed down from the weight of the volcano on Earth. This means magma from magma chambers that are not located directly underneath the volcano can erupt through the volcano. There is a point where the affect of the load from the volcano no longer affects the dikes and the dike will either propagate straight up or to another volcanic load. This is an important topic to study because some day knowing as much as we can about volcanoes could save lives.