硅铝层

硅铝层是地球化学中所指地球的大陆地壳岩石圈，得名于其主要构成化学元素硅与铝。^[1][2]

典型的硅铝层物质， 密苏里州St. Francis Mountains（英语：St. Francis Mountains）正长石基质中的前寒武纪花岗岩。

也称硅铝层岩石为长英质，因为其包含很高比例的硅铝长石矿物。^[3]

硅铝层最初由爱德华·修斯在19世纪提出。已经被岩相、重力测量、地震证据所证实。^[4]

性质

硅铝层的密度低(2700–2800 kg/m^3[5])。与硅镁层分界面并不对应于康拉德不连续面。^[6] 而是相当随意地设定为平均密度2800 kg/m³的地方。^[3]

根据地壳均衡理论^[7] 山脉既向下也向上扩展其岩石圈^[7]，因此大陆地壳的硅铝层厚度从5 km到70 km。^[8]

参见

• 软流圈
• 岩石圈
• 克里普矿物
• 硅镁层

参考文献

1. Continental crust has been defined as That type of the Earth’s crust which underlies the continents and the continental shelves: it is equivalent to the sial. Neuendorf, Klaus K. E.; Mehl, James P.; Jackson, Julia A. (编). Glossary of Geology 5th. Alexandria, Virginia: American Geological Institute. 2005: 139. ISBN 978-3-540-27951-8.
2. Smith, Frederick Gordon. Physical Geochemistry. Reading, Massachusetts: Addison-Wesley. 1963: 379. OCLC 253612701.
3. Ritter, Michael E. Chapter EM: Earth Materials and Structure: The Earth's Interior: The Crust. The Physical Environment: An Introduction to Physical Geography. 2006. （原始内容存档于11 November 2007）.
4. Kuenen, Philip Henry. Marine Geology. New York: Wiley. 1950: 117. OCLC 489742.
5. Fairbridge, Rhodes W. (编). The Encyclopedia of Atmospheric Sciences and Astrogeology. New York: Reinhold Publishing. 1967: 323. OCLC 430153.
6. Monastersky, Richard. Inner Space. Science News. 1989, 136 (17): 266–268, page 266. JSTOR 3973827. doi:10.2307/3973827.
7. Bridges, Edwin Michael. World Geomorphology. Cambridge, England: Cambridge University Press. 1990: 13. ISBN 978-0-521-38343-1.
8. Lliboutry, Luis. Quantitative Geophysics and Geology. London: Springer-Praxis. 2000: 152. ISBN 978-1-85233-115-3.

• Bates, R.L., and Jackson, J.A., (1987) Glossary of geology American Geological Institute, Alexandria, Virginia.
• Dilek, Y. and Newcomb, S. (eds.) (2003) Ophiolite Concept and the Evolution of Geological Thought Geological Society of America Special Paper 373, Boulder, Colorado.