Glaciers and Geology
Glaciers are architects of the Earth, carving valleys, fjords, and basins as they move. Their erosive power is immense: the Laurentide Ice Sheet, which once blanketed much of North America during the last Ice Age, sculpted the Great Lakes, leaving depressions that now hold vast volumes of freshwater. Even smaller alpine glaciers, like those in the Rockies or the Caucasus, shape mountain passes and cirques, leaving visible scars that endure long after the ice retreats.
Main article: Glacier
The process of glacial erosion combines abrasion and plucking. Ice, weighted with embedded rock and sediment, grinds against bedrock like sandpaper, smoothing some surfaces while plucking boulders from others. Over millennia, this slow sculpting creates unique landforms. Fjords in Norway and Chile, some plunging over a kilometer deep, showcase how topography guides ice, amplifying erosive forces and forming dramatic coastal landscapes.
Glacial deposits also preserve geological history. Moraines, drumlins, and till provide clues about past climates, glacier extents, and the composition of underlying bedrock. By studying these features, scientists reconstruct Ice Age landscapes and track shifts in Earth’s climate, bridging geology and climatology in a frozen archive of planetary memory.
