Different types of magma/lava

Basaltic magma

which is high in temperature, very low on silica and with low gas content. This type of magma produces fluid lava with very little explosive activity. It is very runny causing less violent eruptions, usually forming a shield volcano, as it can spread out for - constructive.

Andesitic magma

which is lower in temperature, has more silica and a lot of dissolved gases and is more likely to explode when it reaches the surface. This is very viscous (sticky) causing violent eruption, usually forming composite (steep sided volcanoes), as it doesn't flow too far - destructive.

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