question 9 of 15\nwhy do shield volcanoes have weak eruptions?\na. they feature magma with high silica…

question 9 of 15\nwhy do shield volcanoes have weak eruptions?\na. they feature magma with high silica content.\nb. they form calderas.\nc. they have excess magma.\nd. they feature magma with very low viscosity
Answer
Brief Explanations:
Shield volcanoes have weak eruptions because their magma has very low viscosity. Low - viscosity magma allows gases to escape easily, preventing the build - up of high pressure that leads to explosive eruptions. Magma with high silica content is associated with more explosive eruptions (opposite of what shield volcanoes have). Calderas are formed after large - scale eruptions and not the cause of weak eruptions. Having excess magma doesn't directly relate to the weakness of eruptions.
Answer:
D. They feature magma with very low viscosity