大陆碰撞

大陆碰撞（英语：continental collision）是一种在会聚边界的板块构造运动。这个运动开始于两块陆壳中间隔着一块洋壳，一块陆壳边缘具有俯冲带，而中间的洋壳就在俯冲带下沉消失。在陆壳边缘形成火山弧，如同现今的南美洲安第斯山脉^[1]^[2]。大洋地壳薄（约 6 公里厚）且致密（约 3.3 g/cm³），由玄武岩、辉长岩和橄榄岩组成。因此，大多数洋壳在海沟处很容易俯冲。相比之下，大陆地壳较厚（约 45 公里厚）且有浮力，主要由花岗岩组成（平均密度约为 2.5 克/立方厘米）^[3]。

当另一陆地壳随着下沉板块到达海沟时，因陆地密度低抵抗俯冲，就和对方地壳碰撞。俯冲慢慢停止，火山弧也停止活动。在原海沟的地方造成海岸山脉。原海沟的位置成为也标志着两个地壳之间缝合带。在缝合带常有蛇绿岩套，代表原先海洋地壳和地幔岩石的碎片^[2]

参看文献

^ Toussaint, G.; Burov, E.; Avouac, J.-P. (2004). "Tectonic evolution of a continental collision zone: A thermomechanical numerical model" (PDF). Tectonics. 23 (6): TC6003. Bibcode:2004Tecto..23.6003T. doi:10.1029/2003TC001604
^ ^2.0 ^2.1 O'Brien, P.J. (2001). "Subduction followed by collision; Alpine and Himalayan examples". Physics of the Earth and Planetary Interiors. 127 (1–4): 277–291. Bibcode:2001PEPI..127..277O. doi:10.1016/S0031-9201(01)00232-1
^ Ernst, W.G.; Maruyama, S. Wallis; Wallis, S. (1997). "Buoyancy-driven, rapid exhumation of ultrahigh-pressure metamorphosed continental crust". Proceedings of the National Academy of Sciences. 94 (18): 9532–9537. Bibcode:1997PNAS...94.9532E. doi:10.1073/pnas.94.18.9532. PMC 23212. PMID 11038569

[”Toussaint”-1] Toussaint, G.; Burov, E.; Avouac, J.-P. (2004). "Tectonic evolution of a continental collision zone: A thermomechanical numerical model" (PDF). Tectonics. 23 (6): TC6003. Bibcode:2004Tecto..23.6003T. doi:10.1029/2003TC001604

[”O'Brien”-2] 2.0 ^2.1 O'Brien, P.J. (2001). "Subduction followed by collision; Alpine and Himalayan examples". Physics of the Earth and Planetary Interiors. 127 (1–4): 277–291. Bibcode:2001PEPI..127..277O. doi:10.1016/S0031-9201(01)00232-1

[”-3] Ernst, W.G.; Maruyama, S. Wallis; Wallis, S. (1997). "Buoyancy-driven, rapid exhumation of ultrahigh-pressure metamorphosed continental crust". Proceedings of the National Academy of Sciences. 94 (18): 9532–9537. Bibcode:1997PNAS...94.9532E. doi:10.1073/pnas.94.18.9532. PMC 23212. PMID 11038569

[1]

[2]

[3]