Which risk increases greatly when heavy rainfall saturates volcanic ash depositions?

💡 Explanation

Intense rainfall increases lahar risk because saturation causes **fluidization**, reducing inter-particle friction. This mobilizes volcanic ash and debris into a rapidly flowing slurry; therefore, lahars form rather than stable soil because the liquid limits particle cohesion.

• Which outcome occurs when a meandering stream erodes laterally until encountering a resistant geological formation beneath an oxbow?
• Which process intensifies sediment stratification in a fjord's benthic zone following seasonal meltwater pulses?
• Which outcome occurs when vegetation removal destabilizes dunes?
• Which phenomenon primarily causes uplift along a reverse fault zone?
• Which airflow results when polar and equatorial temperature differences increase?
• Which outcome increases erosion in karst regions because of accelerated chemical weathering?