What causes a strato volcano to erupt?

Answer 1

The Earth has volcanoes because it is hot inside. In some places it is hot enough to turn solid rock into liquid rock. Geologists call the liquid rock magma. The magma rises towards the surface because it is less dense than the surrounding rock (like a hot air balloon rising through the cooler air). If the magma reaches the surface it is called lava and lava accumulates to make a volcano. Volcanoes grow by intrusion and extrusion. An intrusion is magma that moves up into a volcano and then it stops, never erupting. This way the volcano grows on the inside. An extrusion is an eruption. It can add layers of lava or ash. This way the volcano grows on the outside. Volcanoes erupt because of density and pressure. The lower density of the magma causes it to rise (like air bubbles in syrup). It will rise to the surface or to a depth that is determined by the density of the magma and the weight of the rocks above it. As the magma rises, bubbles start to form from the gas dissolved in the magma. The gas bubbles exert tremendous pressure. This pressure helps to bring the magma to the surface and forces it in the air, sometimes to great heights.

Answer 2

eruptions of a fluid ability to flow/ lava, tephra,and pyroclastic happens.