岩浆置入

岩浆置入（英语：pluton emplacement）是指岩浆在岩体中被容纳的方式。对岩浆置入的方法目前尚未完全了解，但许多不同的置入方法被提出，被广泛接受的方法有顶蚀，底辟和膨胀。现在有证据指出岩浆置入是逐渐进行的^[1]。

顶蚀

岩浆的垂直运动是由重力驱动的。当围岩碎块向下掉入岩浆时，就会发生顶蚀。^[2]^[3]顶蚀可以在是各种构造环境中进行，已被广泛用于解释不协调的岩体接触。最常见的顶蚀特征是岩浆和围岩之间的速变不整合接触以及围岩缺乏韧性变形。其他特征包括岩浆中存在捕虏岩、捕获岩的旋转和污染岩浆的地球化学证据^[3]。顶蚀的解释存在一个问题：在岩浆未置入以前，相同岩浆容积的围岩要比岩浆中的捕获岩容积大很多^[4]。

逐渐置入

有众多证据指出，大型均一的岩浆岩是逐渐按岩床型叠加生长的。片状岩浆入侵很常见。一些在岩浆岩体边缘的陡峭倾斜板，原先是水平置入的，然后在岩浆岩底部下垂时倾斜的。但也有人认为是由岩脉构成的。在内华达山脉的麦克杜格尔岩浆岩，是由成分不同的层状岩板组成，并与围岩接触面平行，亦包含许多薄的围岩板^[5]。这种现象是不可能用顶蚀来解释。要到达旧岩浆岩增量的顶部位置，一个新岩浆岩增量必须向上顶蚀穿过先前的岩浆岩增量。岩浆能否上升是由母岩的流变学性质决定：坚硬的岩石能够阻止岩浆上升^[6]^[7]。岩浆置入多以脉冲形进行，如果入侵率足够高，不同的脉冲的入侵可能会混合在一起形成深成岩体（pluton）^[8]^[9]。

膨胀

膨胀是一种置入球形的岩浆方法^[10]，这个模型推论是，当岩浆上升直到它失去热量，并在最外缘形成结晶时，岩浆的较热尾部继续上升，冲裂并扩大已经结晶的外缘。

底辟

底辟是由热的岩浆流体软化围岩一层薄壁而移动^[11]。底辟发生仅限于具有高温和韧性岩石的地幔和下地壳。为了让岩浆上升，必须为它们腾出空间，但方法尚未定论。一个最常被问到的问题是，现在被岩浆岩占据体空间的原来的岩石，到哪里去了？为岩浆上升腾出空间的可行方法是横向延伸，例如中洋脊、走滑断层和扩张缓动区的运动。但是这种伸展速度太慢，滑动幅度太小，无法置入侵入的岩浆 ^[12]。

参考文献

[1]
Paterson, Scott R.; Fowler, T.Kenneth. Re-examining pluton emplacement processes. Journal of Structural Geology. 1993, 15 (2): 191–206. doi:10.1016/0191-8141(93)90095-R.
[2]
Daly, Reginald A. (1903). "The Mechanics of Igneous Intrusion". American Journal of Science. 15. Issue. 88: 269–298.
[3]
Glazner, A. F.; Bartley, J. M. Is stoping a volumetrically significant pluton emplacement process?. Geological Society of America Bulletin. 2006-09-01, 118 (9-10): 1185–1195. ISSN 0016-7606. doi:10.1130/B25738.1.
[4]
Fowler, T. Kenneth (1997). "Timing and the nature of magmatic fabrics from structural relations around stoped blocks". Journal of Structural Geology. 19. No. 2.: 209–224.
[5]
Glazner, A. F.; Bartley, J.; Coleman, S. (2004). "Are plutons assembled over millions of years by amalgamation from small magma chambers?". GSA Today. 14: 114–121.
[6]
Kavanagh, Janine L.; Menand, Thierry; Sparks, R. Stephen J. An experimental investigation of sill formation and propagation in layered elastic media. Earth and Planetary Science Letters. 2006, 245 (3-4): 799–813. doi:10.1016/j.epsl.2006.03.025.
[7]
Leuthold, Julien; Müntener, Othmar; Baumgartner, Lukas P.; Putlitz, Benita; Ovtcharova, Maria; Schaltegger, Urs. Time resolved construction of a bimodal laccolith (Torres del Paine, Patagonia). Earth and Planetary Science Letters. 2012,. 325-326: 85–92. doi:10.1016/j.epsl.2012.01.032.
[8]
de Saint Blanquat, Michel; Horsman, Eric; Habert, Guillaume; Morgan, Sven; Vanderhaeghe, Olivier; Law, Richard; Tikoff, Basil. Multiscale magmatic cyclicity, duration of pluton construction, and the paradoxical relationship between tectonism and plutonism in continental arcs. Tectonophysics. 2011, 500 (1-4): 20–33. doi:10.1016/j.tecto.2009.12.009.
[9]
Leuthold, J; Müntener, O; Baumgartner, L P; Putlitz, B. Petrological Constraints on the Recycling of Mafic Crystal Mushes and Intrusion of Braided Sills in the Torres del Paine Mafic Complex (Patagonia). Journal of Petrology. 2014-05-01, 55 (5): 917–949. ISSN 0022-3530. doi:10.1093/petrology/egu011.
[10]
Vernon, R.; Paterson, S. (1995). "Bursting the bubble of ballooning plutons: A return to nested diapirs emplaced by multiple processes". GSA Bulletin. 107: 1356–1380.
[11]
Marsh, D. B. 1984, On the mechanics of Igneous Diapirism, Stoping and Zone melting, American Journal of Science v. 282 p 808 – 855
[12]
Brooks Hanson, R.; Glazner, Allen F. Thermal requirements for extensional emplacement of granitoids. Geology. 1995, 23 (3): 213. ISSN 0091-7613. doi:10.1130/0091-7613(1995)023<0213:TRFEEO>2.3.CO;2.

[”Scott”-1] [1]
Paterson, Scott R.; Fowler, T.Kenneth. Re-examining pluton emplacement processes. Journal of Structural Geology. 1993, 15 (2): 191–206. doi:10.1016/0191-8141(93)90095-R.

[”Daly”-2] [2]
Daly, Reginald A. (1903). "The Mechanics of Igneous Intrusion". American Journal of Science. 15. Issue. 88: 269–298.

[”Glazne”-3] [3]
Glazner, A. F.; Bartley, J. M. Is stoping a volumetrically significant pluton emplacement process?. Geological Society of America Bulletin. 2006-09-01, 118 (9-10): 1185–1195. ISSN 0016-7606. doi:10.1130/B25738.1.

[”Fowler”-4] [4]
Fowler, T. Kenneth (1997). "Timing and the nature of magmatic fabrics from structural relations around stoped blocks". Journal of Structural Geology. 19. No. 2.: 209–224.

[”Glazner”-5] [5]
Glazner, A. F.; Bartley, J.; Coleman, S. (2004). "Are plutons assembled over millions of years by amalgamation from small magma chambers?". GSA Today. 14: 114–121.

[”Kava”-6] [6]
Kavanagh, Janine L.; Menand, Thierry; Sparks, R. Stephen J. An experimental investigation of sill formation and propagation in layered elastic media. Earth and Planetary Science Letters. 2006, 245 (3-4): 799–813. doi:10.1016/j.epsl.2006.03.025.

[”Leut”-7] [7]
Leuthold, Julien; Müntener, Othmar; Baumgartner, Lukas P.; Putlitz, Benita; Ovtcharova, Maria; Schaltegger, Urs. Time resolved construction of a bimodal laccolith (Torres del Paine, Patagonia). Earth and Planetary Science Letters. 2012,. 325-326: 85–92. doi:10.1016/j.epsl.2012.01.032.

[”Sain”-8] [8]
de Saint Blanquat, Michel; Horsman, Eric; Habert, Guillaume; Morgan, Sven; Vanderhaeghe, Olivier; Law, Richard; Tikoff, Basil. Multiscale magmatic cyclicity, duration of pluton construction, and the paradoxical relationship between tectonism and plutonism in continental arcs. Tectonophysics. 2011, 500 (1-4): 20–33. doi:10.1016/j.tecto.2009.12.009.

[”Leuth”-9] [9]
Leuthold, J; Müntener, O; Baumgartner, L P; Putlitz, B. Petrological Constraints on the Recycling of Mafic Crystal Mushes and Intrusion of Braided Sills in the Torres del Paine Mafic Complex (Patagonia). Journal of Petrology. 2014-05-01, 55 (5): 917–949. ISSN 0022-3530. doi:10.1093/petrology/egu011.

[”Vern”-10] [10]
Vernon, R.; Paterson, S. (1995). "Bursting the bubble of ballooning plutons: A return to nested diapirs emplaced by multiple processes". GSA Bulletin. 107: 1356–1380.

[”-11] [11]
Marsh, D. B. 1984, On the mechanics of Igneous Diapirism, Stoping and Zone melting, American Journal of Science v. 282 p 808 – 855

[”Hanson”-12] [12]
Brooks Hanson, R.; Glazner, Allen F. Thermal requirements for extensional emplacement of granitoids. Geology. 1995, 23 (3): 213. ISSN 0091-7613. doi:10.1130/0091-7613(1995)023<0213:TRFEEO>2.3.CO;2.

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