Which consequence results when tephra accumulation obstructs streams?

💡 Explanation

Lahars rapidly form because complete tephra blockage will suddenly fail causing a debris flow. The **plug failure** results in mobilized volcanic material from upstream accumulation; therefore, lahars, rather than slower processes or unrelated phenomena, are the key immediate risk.

• Which landform evolution results when multiple cirques erode different sides of a mountain?
• Which long-term outcome results as a tectonic valley fills with sediment eroded through hydraulic action from a central, elevated source?
• Which immediate ecosystem shift occurs when methane clathrates destabilize along a subduction zone?
• Which mechanism maintains relatively stable ocean surface temperatures globally due to latitudinal variations?
• Which mechanism causes significant elevation change after a megathrust earthquake near a coastline?
• Which process impacts mineral transformation during advanced pedogenesis?