GEOLOGY

Detailed explanation-1: -So, mafic lavas are hot, low in silica and volatiles, and have relatively low viscosity. They flow easily outward from the vent (where it comes out of the ground), and may travel great distances before completely solidifying. Felsic lavas are not as hot, high in silica and volatiles, and have a high viscosity.

Detailed explanation-2: -Differences in a magma’s viscosity will determine the shape a volcano takes. High-silica (basalt) magma has a much lower viscosity. It flows much easier and over longer distances. As low-silica magma cools, it hardens to rock, adding a new thin layer of rock to the volcano.

Detailed explanation-3: -The viscosity of most lava is about that of ketchup, roughly 10, 000 to 100, 000 times that of water.

Detailed explanation-4: -You can measure lava in terms of viscosity as well. And the lava viscosity defines the size and shape of a volcano. Even though lava is 100, 000 times more viscous than water, it can still flow great distances. When lava has low viscosity, it can flow very easily over long distances.