Question

How is a composite volcano formed?

Answer 1

The essential feature of a composite volcano is a conduit system through which magma from a reservoir deep in the Earth's crust rises to the surface. The volcano is built up by the accumulation of material erupted through the conduit and increases in size as lava, cinders, ash, etc., are added to its slopes

Answer 2

Magma from a reservoir deep in the Earths crust rises to the surface.