岩盖(英语:Laccolith)是一种片状的侵入体(或是一致的深成岩体)。它侵入到了沉积岩层内或层之间;当母岩为火山岩时,该岩盖被称为隐形穹(cryptodomes)[1]。由于岩浆的压力足够高,以致上覆岩层被迫向上并隆起,从而使岩盖在并具有基本平坦的底部的同时顶部呈圆拱或蘑菇状(也可能为圆锥形或楔形)。 随着时间的流逝,侵蚀可能会使岩盖的顶部周围形成小山甚至山峦,因为岩浆岩可能比作为基质的沉积岩更能抵抗风化。 当岩浆向上侵入时,岩盖的生长可能在几个月的时间里发生[2][3] 。而由于多个岩浆脉彼此叠加使基岩变形时,岩盖的形成则可能需要数百或数千年的时间[4]

岩盖入侵并使顶层的沉积岩变形
侵入岩结构的基本构成
1. 岩盖
2. 小的岩脉
3. 岩磐
4. 岩脉
5. 岩干
6. 火山颈
7. 岩盆

参考资料

  1. ^ Burchardt, Steffi; Mattsson, Tobias; Palma, J. Octavio; Galland, Olivier; Almqvist, Bjarne; Mair, Karen; Jerram, Dougal A.; Hammer, Øyvind; Sun, Yang. Progressive Growth of the Cerro Bayo Cryptodome, Chachahuén Volcano, Argentina—Implications for Viscous Magma Emplacement. Journal of Geophysical Research: Solid Earth. 2019-08-14, 124 (8): 7934–7961. Bibcode:2019JGRB..124.7934B. ISSN 2169-9313. doi:10.1029/2019JB017543. 
  2. ^ Castro, Jonathan M.; Cordonnier, Benoit; Schipper, C. Ian; Tuffen, Hugh; Baumann, Tobias S.; Feisel, Yves. Rapid laccolith intrusion driven by explosive volcanic eruption. Nature Communications. December 2016, 7 (1): 13585. Bibcode:2016NatCo...713585C. ISSN 2041-1723. PMC 5123016 . PMID 27876800. doi:10.1038/ncomms13585. 
  3. ^ Mattsson, Tobias; Burchardt, Steffi; Almqvist, Bjarne S. G.; Ronchin, Erika. Syn-Emplacement Fracturing in the Sandfell Laccolith, Eastern Iceland—Implications for Rhyolite Intrusion Growth and Volcanic Hazards. Frontiers in Earth Science. 2018-02-05, 6: 5. Bibcode:2018FrEaS...6....5M. ISSN 2296-6463. doi:10.3389/feart.2018.00005. 
  4. ^ Morgan, Sven; Stanik, Amy; Horsman, Eric; Tikoff, Basil; de Saint Blanquat, Michel; Habert, Guillaume. Emplacement of multiple magma sheets and wall rock deformation: Trachyte Mesa intrusion, Henry Mountains, Utah. Journal of Structural Geology. April 2008, 30 (4): 491–512. Bibcode:2008JSG....30..491M. doi:10.1016/j.jsg.2008.01.005. 
  • Blatt, Harvey and Robert J. Tracy, 1996, Petrology: Igneous, Sedimentary and Metamorphic, 2nd ed., pp. 13–15, Freeman, ISBN 0-7167-2438-3
  • Jules D. Friedman and Curtis Huffman, Jr., coordinators, "Laccolith Complexes of Southeastern Utah: Time of Emplacement and Tectonic Setting -- Workshop Proceedings"页面存档备份,存于互联网档案馆), United States Geological Survey Bulletin 2158, 1998.
  • Hyndman, D. W. and D. Alt "Radial Dikes, Laccoliths, and Gelatin Models." ' 'Journal of Geology. 95:763-774.

外部链接