Processes of glacial weathering, erosion and the characteristics and formation of associated landforms and landscapes

Glacial weathering and erosion are fundamental processes that shape high-latitude and high-altitude landscapes. Weathering in glacial environments is dominated by freeze-thaw action (frost shattering), where water repeatedly freezes and thaws in cracks, breaking rock into angular fragments. Chemical weathering is limited due to cold temperatures but can occur in subglacial environments where meltwater is present. These weathered materials become tools for glacial erosion.

Glacial erosion occurs through two main processes: abrasion and plucking. Abrasion happens as debris embedded in the ice scrapes against bedrock, smoothing and polishing it, often leaving striations. Plucking (or quarrying) occurs when meltwater refreezes around jointed bedrock, and as the glacier moves, it pulls out blocks of rock. The effectiveness of erosion depends on ice thickness, velocity, and the hardness of the underlying rock.

These processes create distinctive landforms. On a small scale, striations and glacial polish indicate abrasion, while crescentic gouges and chatter marks show plucking. Larger landforms include corries (cirques), arêtes, pyramidal peaks, U-shaped valleys, hanging valleys, and ribbon lakes. The formation of each landform involves specific combinations of weathering, erosion, and sometimes deposition. Understanding these processes is crucial for interpreting past glacial environments and predicting landscape change in a warming climate.