Massif

A massif is a large, coherent block of the Earth’s crust that forms a compact mountainous region and is typically bounded by faults or structural boundaries. In geology, massifs are blocks that have moved or tilted as a single unit and have remained relatively rigid compared to surrounding rocks.

Massifs arise from tectonic processes such as uplift, faulting, and crustal thickening during orogeny. They are often built from ancient, resistant rocks such as granites, gneisses, and other metamorphic or igneous rocks, though their composition can vary. Erosion over time shapes the surface of a massif into rugged peaks, steep sides, and deep valleys, but the block itself tends to retain coherence, distinguishing it from a simple collection of separate mountains.

In geographic use, the term massif is commonly applied to large upland regions that behave as a single structural unit within a larger mountain system. Massifs are not the same as mountain ranges or plateaus, though they may contain both peaks and high, escarped terrain. Their boundaries are defined by faults or major tectonic features, and their interiors can host diverse ecosystems and watersheds.

Notable examples in Europe include the Massif Central, Armorican Massif, Vosges Massif, and Ardennes, all of which refer to distinct regions where the crust has formed a recognizable, relatively cohesive block. The concept is widely used in regional geology and geomorphology to describe large, structurally coherent highlands across the world.