Highly explosive magmas are controlled by which of the following?
A) high magnesium content and high water
B) high silica content and high water
C) low silica content and high water
D) high silica content and low water
E) high iron content and low water

Question

Quizplus · Accepted Answer

Highly explosive magmas are controlled by high silica content and high water. This combination results in a high viscosity magma, which easily traps gases inside, leading to explosive eruptions. High magnesium content and high iron content may increase the temperature of the magma but do not necessarily increase its explosiveness. Similarly, low silica content and high water may result in more fluid magma that produces effusive eruptions rather than explosive ones.

Highly Explosive Magmas Are Controlled by Which of the Following