Intro:
• Mantle plume – a localized column of hot, solid material rising from deep mantle (~core-mantle boundary) to lithosphere.
• First proposed by J. Tuzo Wilson; central to explaining intraplate volcanism.
Characteristics:
• Temperature anomaly, low-density material.
• Creates volcanic hotspots (e.g., Hawaii, Réunion).
• Independent of plate boundaries.
Role in Plate Tectonics:
• Hotspot Volcanism – Plumes generate magma that forms island chains as plates move over them (e.g., Hawaiian-Emperor Seamount Chain).
• Plate Movement Trigger – Rising plumes weaken lithosphere, aid in rifting and plate break-up (e.g., Afar plume – East African Rift).
• Formation of Flood Basalts – Large Igneous Provinces like Deccan Traps linked to plume activity.
• Thermal Convection Contribution – Plumes support mantle convection, a driver of plate motion.
Conclusion:
• Mantle plumes are critical in understanding both intraplate volcanism and driving mechanisms of plate tectonics.
