Which progression results when differential wave erosion undermines a stack?

💡 Explanation

Arch formation precedes collapse because wave action erodes less resistant material at the stack's base via hydraulic action, creating an arch. Therefore, an arch forms until the roof collapses under gravity, rather than protective caprock or lagoon growth.

• Which outcome occurs when a river's competence reduces significantly at the base of a mountain range, leading to deposition?
• Which mechanism accelerates barrier island submergence during increased storm frequency?
• Which prevailing wind effect results from the interaction of subtropical high-pressure zones and Earth's rotation?
• Which mechanism causes increased liquefaction risk during seismic shaking of unconsolidated coastal sediments?
• Which risk strongly increases due to differential weathering when loess deposits overly bedrock?
• Which ecosystem change results when pyroclastic flows deposit large amounts of ash?