Here's why:
* Low Silica Content: Shield volcanoes are characterized by their basaltic lava, which has a low silica content. Basaltic lava is very fluid and flows easily, creating the gentle, sloping shape of shield volcanoes.
* High Silica Content: Volcanoes with high silica content in their lava (like rhyolitic lava) tend to be explosive and form composite volcanoes (also known as stratovolcanoes), characterized by steep slopes and alternating layers of lava and ash.
Key takeaways:
* Shield volcanoes are associated with basaltic magma, which is low in silica.
* High silica content in lava is associated with explosive eruptions and composite volcanoes.
Let me know if you have any other questions!
