GEOLOGY

Detailed explanation-1: -The way a volcano erupts depends on the amount of gas and silica (a molecule of silicon oxygen) in the magma below. Magma with lots of silica is thick and gooey, while magma low in silica is thin and runny. And in magma with lots of gas, bubbles form as it rises.

Detailed explanation-2: -Magmas that have a high silica content will therefore exhibit greater degrees of polymerization, and have higher viscosities, than those with low-silica contents. The amount of dissolved gases in the magma can also affect it’s viscosity, but in a more ambiguous way than temperature and silica content.

Detailed explanation-3: -Magmas with high silica content have a high viscosity (resistance to flow) and are generally more explosive when eruptions occur. All magmas also contain some degree of trapped gasses (CO2 & H2O ).

Detailed explanation-4: -Because volcanic magma becomes more silica-rich with time, its explosive potential increases.

Detailed explanation-5: -Silica-rich magma is highly explosive because the gases within the magma build up within the highly viscous magma and burst when pressure is too great. Viscosity is defined as the stickiness or thickness of a liquid when flowing, and silica can create this stickiness within magma.