Volcanoes are grouped into four types: cinder cones, composite volcanoes, shield volcanoes and lava volcanoes. Cinder cones are circular or oval cones made up of small fragments of lava from a single ...

Most volcanoes form at the boundaries of Earth's tectonic plates, which are huge slabs of crust and upper mantle that fit together like puzzle pieces. Think of these plates as massive rafts floating ...

When the plate sinks into the mantle it melts to form magma. The pressure of the magma builds up beneath the Earth's surface. The magma escapes through weaknesses in the rock and rises up through a ...