EPSC 185 Lecture 4: vocalno notes

• School: McGill University
• Department: Earth & Planetary Sciences
• Course: EPSC 185
• Professor: John Stix

Document Summary

Violently(pyroclasti) violently ash eruption is dangerous magma breaks into fragment (andesite basalt ??) Two controls on explosivity are: (1) the silica content and (2) the gas content of the magma. Magmas with higher silica contents are more viscous there are magmas and then become pyroclastic and lava depending on the strength and their physical prosperity ) Lave first and the pyroclastic latter is less common. Volcano also can result in tsunami or surge: divergent boundary. The magma erupts mainly as basaltic lava flows. Subduction zone: the subducted oceanic plate heats as it plunges, at a depth of 80-120 km, melting, volcano parallel to the subduction, domain position is interside. Magmas from deep within the mantle begins zone: mantle plumes stationary relative to the drifting tectonic plates( hotter than the rest of mantle. The lave traveled the caldera becomes empty/or half empty and then the proof went tthe bottom of the lake. Block move down, along with the faults, earthquake generated.