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Geological History
Published in F.G.H. Blyth, M. H. de Freitas, A Geology for Engineers, 2017
F.G.H. Blyth, M. H. de Freitas
Mountain building has taken place at intervals throughout geological time and the major periods of mountain building are shown in Table 2.1, column 6. The term orogeny is used for this mountain building activity (Greek oros, a mountain). In the fold belts the rocks are now seen, after denudation, to have been thrown into complex folds. They are zones of instability in the crust, or mobile-belts. The parts of continents adjacent to them are relatively stable areas but subject to vertical or epeirogenic movements (Greek epeiros, a continent). Epeirogenic and orogenic movements are related to changes in the relative positions of plates of the lithosphere: Fig. 2.3 illustrates an example of this relationship.
Earth Systems and Cycles
Published in Dexter Perkins, Kevin R. Henke, Adam C. Simon, Lance D. Yarbrough, Earth Materials, 2019
Dexter Perkins, Kevin R. Henke, Adam C. Simon, Lance D. Yarbrough
Orogeny is a general term used to describe large structural deformation of the continental lithosphere that produces long, relatively narrow belts called orogenic belts, or simply orogens. The process involved is termed orogenesis. Topographically, many of these belts are mountainous and are commonly called mountain belts or mountain ranges. Figure 2.41 shows, in blue, the most significant orogens active today or within the past several hundred million years.
A review of major rare earth element and yttrium deposits in China
Published in Australian Journal of Earth Sciences, 2022
An orogeny is a mountain building tectonic event with compression associated with orthogonal folds and thrust faults, and oblique faults (Ren et al., 1994). REEs are deposited in this setting where fluids travel through faults acting as conduits. The fluid interacts with the wall rocks, forming alteration zones enriched in REY. Faults also act as pathways for the intrusion of magma, forming plutons and dykes, such as carbonatite containing REY.