Which phenomenon initiates volcanic island formation above hotspots?

💡 Explanation

Mantle plumes drive hotspot volcanism, because rising hot material undergoes decompression melting as pressure decreases; therefore, islands form from continuous lava flows, rather than from immediate uplift/erosion of existing rock.

• Which abrasive outcome is amplified when ventifact formation occurs in a sodium-rich lacustrine environment?
• Which outcome increases near groynes, because of longshore transport disruption?
• Which mechanism exacerbates flood risk when levees fail?
• Which outcome occurs when shield volcanoes overly a hotspot?
• Which risk increases when volcanic tephra accumulates on glaciers?
• Which effect contributes to desert formation along the western coasts of continents associated with strong subtropical gyres?