As a general rule, eruptions which are separated by less than 90 days are considered to be phases of the same episode unless there is a large change in the style of the eruption. Type of Volcanic Cones Shield volcanos are associated with Hawaiian or fissure type volcanos. They result from eruptions of low viscosity lava which spreads out over a wide area and which can gradually build up. The big island of Hawaii is an example of an enormous shield volcano. Shield volcanos sometimes have a caldera at the top resulting from subsidence into the magma chamber below the volcano.
Cinder cones are usually small.
Essentially a large pile of rocks, large cinder cones are unstable and prone to landslides. They consist of alternating layers of cinders and lava flows. The lava flows serve to glue everything together resulting in a much stronger cone and, unlike cinder cones, composite volcanos can grow to great heights. Despite their greater strength and stability, composite cones are still prone to some collapse and landslides. The large and beautiful volcanos of Guatemala are all composite volcanos.