Which phenomenon causes lahars with destructive debris flows?

💡 Explanation

A jökulhlaup generates massive debris flows because ice melts due to geothermal or volcanic activity, forming a slurry; therefore lahars follow the valleys rather than other geophysical upheavals, which cause crustal shifting.

• Which risk substantially increases when impermeable coastal defenses interrupt sediment transport?
• Which process causes the formation of distributary channels on an alluvial fan?
• Which outcome is initiated by thermohaline circulation changes affecting ocean streams?
• Which consequence results when eustatic sea-level rise breaches barrier island dunes?
• Prolonged rainfall increases stress on river levees, causing which failure mode when shear strength decreases?
• Which process generates seismic waves characterized by high frequency and rapid attenuation during shallow crustal earthquakes?