Volcanic eruptions in Europe are caused by the movement of tectonic plates. Europe is located on the boundary of the Eurasian, African, and Arabian plates, which are all actively moving. When these plates move against each other, it can cause the formation of magma chambers beneath the Earth's surface. As pressure builds up within these chambers, it can cause volcanic eruptions. Additionally, Europe is home to a number of active and dormant volcanoes, such as Mount Etna in Italy, which can also experience eruptions due to the movement of tectonic plates or other factors such as changes in the geothermal activity of the region.