<P> Most volcanoes occur in a band encircling the Pacific Ocean (the Pacific Ring of Fire), and in another that extends from the Mediterranean across Asia to join the Pacific band in the Indonesian Archipelago . The most important types of volcanic mountain are composite cones or stratovolcanoes (Vesuvius, Kilimanjaro and Mount Fuji are examples) and shield volcanoes (such as Mauna Loa on Hawaii, a hotspot volcano). </P> <P> A shield volcano has a gently sloping cone due to the low viscosity of the emitted material, primarily basalt . Mauna Loa is the classic example, with a slope of 4 ° - 6 ° . (The relation between slope and viscosity falls under the topic of angle of repose .) The composite volcano or stratovolcano has a more steeply rising cone (33 ° - 40 °), due to the higher viscosity of the emitted material, and eruptions are more violent and less frequent than for shield volcanoes . Besides the examples already mentioned are Mount Shasta, Mount Hood and Mount Rainier . </P> <P> When plates collide or undergo subduction (that is--ride one over another), the plates tend to buckle and fold, forming mountains . Most of the major continental mountain ranges are associated with thrusting and folding or orogenesis . Examples are the Jura and the Zagros mountains . </P> <P> When a fault block is raised or tilted, block mountains can result . Higher blocks are called horsts and troughs are called grabens . A spreading apart of the surface causes tensional forces . When the tensional forces are strong enough to cause a plate to split apart, it does so such that a center block drops down relative to its flanking blocks . </P>

The andes mountains were created by what type of mountain building process