Geomorphology

Lore & Background

Geomorphology examines how Earth's surface is modified by surface processes—water, wind, ice, wildfire, life, chemical reactions, gravity, and human activity—and by geologic processes such as tectonic uplift, volcanic growth, isostatic changes, and sedimentary basin formation. These processes intersect climatic, hydrologic, and biologic action with geologic action, or the lithosphere with the hydrosphere, atmosphere, and biosphere. Broad-scale topographies like mountain belts illustrate this intersection: uplift produces sediment that is transported and deposited elsewhere, while individual landforms evolve from the balance of additive processes (uplift and deposition) and subtractive processes (subsidence and erosion). Feedbacks occur, such as topography modifying local climate via orographic precipitation, which in turn alters the hydrologic regime and topography.

Reader's Guide

Geomorphology provides a framework for understanding landscape evolution and dynamics across scales, from mountain belts to individual hillslopes. Its practical applications include hazard assessment (e.g., landslide prediction and mitigation), river control and stream restoration, and coastal protection. The field also extends to planetary geomorphology, studying landforms on other terrestrial planets such as Mars, using Earth analogues to aid interpretation. Geomorphologists employ diverse techniques: fieldwork, remote sensing, geochemical analyses, numerical modeling, geochronology, and terrain measurement (differential GPS, digital terrain models, laser scanning). The discipline's broad base of interests—spanning physical geography, geology, geodesy, engineering geology, archaeology, climatology, and geotechnical engineering—contributes to many research styles.

Did You Know?

• Ancient Greek historian Herodotus argued from soil observations that the Nile Delta was actively growing into the Mediterranean Sea.
• Song dynasty scientist Shen Kuo theorized that a cliff with marine fossils was once a prehistoric seashore that had shifted hundreds of miles.
• Planetary geomorphology studies landforms on other terrestrial planets such as Mars, including effects of wind, fluvial, glacial, and volcanic processes.