In geology, a geological shoulder or rift shoulder is an area of uplifted terrain resulting from the compensatory movement of large-scale tectonic processes. These features are distinct from reliefs caused by compressional tectonics, as they arise from extensional forces rather than compression. [1]
Rift shoulders are significant topographic features, often reaching elevations of several kilometers, that form mountainous belts along the edges of central rift depressions. The origin of these shoulders has been the subject of extensive research since the 1980s. [1] The isostatic compensation model proposed by Felix Andries Vening Meinesz in 1950, also known as the isostatic or flexural rebound model, explains the permanent topographic uplift that occurs during rifting and persists on passive margins despite erosion. [2] This model is complemented by additional theories that account for factors such as creep, mantle magma underplating, or dynamic support. These explore the influence of rheological parameters, extension rates, crustal thickness, and fault geometry in greater detail. [3]
Examples of geological shoulders are:
These examples highlight the global distribution of geological shoulders and their association with major tectonic features. [4]
