Magma in quiet eruptions has a low content in silica , while in explosive eruptions, it has a high Content in silica. A volcano that erupts quietly has magma that is low in silica. Low-silica magma has low viscosity and flows easily. A volcano that erupts explosively has magma that is high in silica. High-silica magma has high viscosity, making it thick and sticky, thus it flows slowly.
