massmovement

Mass movement, in geomorphology and geology, refers to the downslope transfer of rock, soil, and other earth materials under the influence of gravity. It encompasses a spectrum from very slow creep to rapid landslides, including rockfalls, rock avalanches, debris slides, debris flows, and mudflows. Movement is driven by gravity and modulated by material properties, slope angle, water content, vegetation, and seismic shaking. Triggers can include intense rainfall, snowmelt, earthquakes, human disturbance, and volcanic activity. Mass movement shapes landscapes, alters drainage patterns, and poses risks to settlements and infrastructure, making hazard assessment and monitoring important in affected regions.

In sociology and political science, mass movement refers to organized, large-scale collective action aimed at achieving social, political, or economic change. Mass movements mobilize participants beyond conventional political channels, often drawing on shared grievances, collective identity, and frame articulation that defines goals. They vary from spontaneous protests to long-running organizations with formal leadership, ideology, and resource networks. The study of mass movements examines mobilization processes, recruitment strategies, leadership dynamics, communication networks, and interactions with institutions, opponents, and counter-movements. Examples include civil rights movements, anti-colonial movements, labor and feminist movements, environmental campaigns, and contemporary digital-era activism.

Note: the standard term in most contexts is two words, “mass movement.” The concatenated form “massmovement” is uncommon in scholarly writing and is typically encountered only as a product name or informal label.