| Zusammenfassung |
Volcanic eruptions present risks to human life and welfare, especially in rapidly growing urban areas. Detecting the rhythms and cycles of magma movement beneath a volcano is crucial to understanding their future behaviour. Magma - the molten rock that builds the Earth's crust and feeds volcanoes - spends most of its existence as part of a 'mush' zone under the surface, comprising a complicated mixture of crystals, liquid molten rock and volcanic gases. We know from investigating patterns in the texture and composition of volcanic rocks, that fluids can move through mushes, especially in the periods before and during eruptions. This process is important because it allows the accumulation of the type of mobile magma that reaches the Earth's surface during eruptions. However, we do not know exactly what effects this movement produces at the Earth's surface where we are best positioned to detect them. Measuring tiny movements of the Earth's surface is an important way of assessing how active a volcano is, and is widely used by volcano observatories to forecast eruptions. My research uses satellite data to make these measurements over very large areas. A particularly exciting aspect of this is that I can make displacement measurements globally and in poor and inaccessible regions where there is no or limited instrumentation installed on the ground. I and my colleagues have found an increasing number of examples of subsidence (caused by volume loss under the surface) and uplift (volume gain) occurring within a short time interval, but at a distance of many kilometres apart. These observations provide unique pieces of information about the time and distance over which magma travels underground that I will use to develop new models for interpreting displacement measurements. I will use these models to determine what displacements measured from satellites look like when magma is accumulating before a volcanic eruption. |