俯冲带变质作用

俯冲带变质作用(英语:subduction zone metamorphisim)是指在岩石圈向下俯冲过程中,所经历的低温,高到超高压变质环境,形成的一系列的变质岩相的矿物组合[1]。由浅到深,变质岩相是沸石相(英语:zeolite facoies)、葡萄石-绿纤石相蓝片岩相和榴辉岩相(英语:eclogite facies[2][3] [4].俯冲板块由玄武质地壳和上覆远海沉积物组成, 然而,远海沉积物多半被增生到弧前地区而不俯冲到深部[5]。在俯冲中,板块的变质多半是由含水矿物脱水引起的。含水矿物的分解通常在 10 公里的深度开始,将水释放到地幔中。从而降低了地幔岩石的熔点,引发了部分熔融[6]。 这些变质岩相中,每一个都有指标矿物组合,代表其经历的变质环境[7]。 了解这些脱水反应发生的时间和条件,是解释地幔熔融、火山弧岩浆作用和大陆地壳形成的关键[8]

参考文献

编辑
  1. ^ Tatsumi, Yoshiyuki (2005). "The subduction factory: How it operates in the evolving Earth" (PDF). GSA Today. 15 (7): 4. doi:10.1130/1052-5173(2005)015[4:TSFHIO]2.0.CO;2. Retrieved December 3, 2014.
  2. ^ Zheng, Y.-F., Chen, R.-X., 2017. Regional metamorphism at extreme conditions: Implications for orogeny at convergent plate margins. Journal of Asian Earth Sciences 145, 46-73
  3. ^ Winter, John D. (2010). Principles of Igneous and Metamorphic Petrology. Prentice Hall. pp. 541–548. ISBN 978-0-321-59257-6
  4. ^ Reynolds, Stephen (2012-01-09). Exploring Geology. McGraw-Hill. p. 124. ISBN 978-0073524122
  5. ^ Bebout, Grey E. (May 31, 2007). "Metamorphic Chemical Geodynamics of Subduction". Earth and Planetary Science Letters. 260: 375. Bibcode:2007E&PSL.260..373B. doi:10.1016/j.epsl.2007.05.050
  6. ^ Peacock, Simon M. (1 January 2004). "Thermal Structure and Metamorphic Evolution of Subducting Slabs". In Eiler, John (ed.). Inside the subduction factory. Geophysical Monograph Series. 138. American Geophysical Union. pp. 12–15. ISBN 9781118668573
  7. ^ "How Volcanoes work – Subduction Zone Volcanism". San Diego State University Department of Geological Science
  8. ^ Mibe, Kenji; et al. (2011). "Slab melting versus slab dehydration in subduction zones". Proceedings of the National Academy of Sciences. 108 (20): 8177–8182. doi:10.1073/pnas.1010968108. PMC 3100975. PMID 21536910