What is composite volcanoes magma chemistry?

Composite volcanoes, also known as stratovolcanoes, primarily erupt magma that is andesitic in composition, which is intermediate between basaltic and rhyolitic magmas. This magma is characterized by higher viscosity due to its silica content, which leads to more explosive eruptions. The presence of volatiles, such as water and carbon dioxide, in the magma contributes to the formation of gas-rich eruptions, resulting in the characteristic steep-sided structure of composite volcanoes. Overall, the magma chemistry plays a critical role in determining the eruptive behavior and morphology of these volcanoes.