A geomorphological depression bounded by higher terrain, formed primarily through fluvial or glacial processes. Fluvial valleys arise from sustained river incision and typically exhibit V-shaped cross-sections due to dominant vertical erosion in upper catchment zones. Glacial valleys develop through abrasion and plucking by moving ice masses, producing U-shaped profiles with steep sidewalls and broad floors. Valley morphology is further influenced by lithology, tectonic uplift, climatic regime, and sediment load, resulting in a spectrum of valley types including hanging valleys, rift valleys, and trough valleys.
River Valley
A fluvially carved geomorphological depression formed by the sustained erosional activity of a river system. River valleys commonly originate as narrow, V-shaped incisions in upland or mountainous terrain where vertical (downcutting) erosion dominates. As the river progresses downstream and gradients decrease, lateral erosion and sediment deposition widen the valley floor, producing broader alluvial valleys characterized by floodplains, terraces, and meander belts. River valley morphology is controlled by factors such as bedrock lithology, tectonic uplift rates, hydrologic regime, sediment supply, and climatic conditions. Distinct subtypes include youthful V-shaped valleys, mature open valleys with developed floodplains, and senile low-gradient valleys approaching base level.
Glacial Valley
A U-shaped geomorphological depression produced by the erosive action of a valley glacier. Unlike fluvially incised valleys, glacial valleys exhibit broad, flat floors and steep, straight sidewalls resulting from combined processes of abrasion, plucking, and subglacial deformation. As a glacier advances, it deepens and widens pre-existing river valleys by scouring bedrock and entraining debris. Glacial valley systems commonly include associated landforms such as hanging valleys, truncated spurs, overdeepenings, cirques at headwalls, and depositional features like moraines and till plains. Valley morphology is controlled by ice thickness, basal thermal regime, bedrock structure, and the duration and dynamics of glaciation.
