The Chile Ridge, also known as the Chile Rise, is a submarine oceanic ridge formed by the divergent plate boundary between the Nazca plate and the Antarctic plate. It extends from the triple junction of the Nazca, Pacific, and Antarctic plates to the Southern coast of Chile.[1][2] The Chile Ridge is easy to recognize on the map, as the ridge is divided into several segmented fracture zones which are perpendicular to the ridge segments, showing an orthogonal shape toward the spreading direction. The total length of the ridge segments is about 550–600 km.[1]
The continuously spreading Chile Ridge collides with the southern South American plate to the east, and the ridge has been subducting underneath the Taitao Peninsula since 14 million years ago (Ma).[1][2] The ridge-collision has generated a slab window beneath the overlying South America Plate, with smaller volume of upper mantle magma melt, proven by an abrupt low velocity of magma flow rate below the separating Chile ridge.[2][1][3] The subduction generates a special type of igneous rocks, represented by the Taitao ophiolites, which is an ultramafic rock composed of olivine and pyroxene, usually found in oceanic plates.[4][2] In addition, the subduction of the Chile Ridge also creates Taitao granite in Taitao Peninsula which appeared as plutons.[2][5]
The Chile Ridge involves spreading ridge subduction which is worth studying because it explains how the Archean continental crust initiation formed from deep oceanic crust.[4]
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:1was invoked but never defined (see the help page). - ^ a b Bourgois, Jacques; Lagabrielle, Yves; Martin, Hervé; Dyment, Jérôme; Frutos, Jose; Cisternas, Maria Eugenia (2016), A Review on Forearc Ophiolite Obduction, Adakite-Like Generation, and Slab Window Development at the Chile Triple Junction Area: Uniformitarian Framework for Spreading-Ridge Subduction, Pageoph Topical Volumes, Cham: Springer International Publishing, pp. 3217–3246, doi:10.1007/978-3-319-51529-8_2, ISBN 978-3-319-51528-1, retrieved 2021-11-10
- ^ Anma, Ryo; Armstrong, Richard; Orihashi, Yuji; Ike, Shin-ichi; Shin, Ki-Cheol; Kon, Yoshiaki; Komiya, Tsuyoshi; Ota, Tsutomu; Kagashima, Shin-ichi; Shibuya, Takazo (November 2009). "Are the Taitao granites formed due to subduction of the Chile ridge?". Lithos. 113 (1–2): 246–258. Bibcode:2009Litho.113..246A. doi:10.1016/j.lithos.2009.05.018. hdl:2241/104215. ISSN 0024-4937.