Question

Which combination of viscosity and gas content of the magma is most likely to lead to a very explosive volcanic eruption? a. low viscosity, low gas content b. low viscosity, high gas content c. high viscosity, low gas content d. high viscosity, high gas content

Answer 1

D. High viscosity, high gas content

Explaintion

Explosive eruptions are favored by high gas content & high viscosity magmas (andesitic to rhyolitic magmas). The explosive bursting of bubbles fragments the magma into clots of liquid that cool as they fall through the air.