盐构造

盐构造（英语：salt tectonics）是指岩石地层序列中有厚层岩盐导致变形。这是由于盐的密度低，不会随著埋而增加，而且强度低^[1]。盐构造一般分被动和主动两种。

被动盐构造

由重力造成。在沉积盆地内，若有早期沉积的盐层被后期的沉积物持续增厚覆盖，能导致重力不稳定，就会形成盐构造。纯岩盐密度每立方米2160公斤，而一般沉积物密度通常较低，为每立方米2000公斤，但随著加载和压实，密度增至每立方米2500公斤，大于盐的密度，造成上重下轻的重力不稳定。盐层就会延覆盖地层的构造弱点向上移动形成凸脊^[2]。凸脊的盐由周围盐层提供因而形成凹陷，随著上覆地层加厚，凸脊继续增高，持续到周围盐层耗尽而形成底辟。如果原始盐层够厚，底辟的顶部能接近地表^[3]。

主动盐构造

由构造活动造成。例如在伸展构造地区，断层作用会降低上覆地层的强度并使其变薄。导致盐层上升^[4]，在逆冲构造地区，上覆地层的湾曲将使盐层上升到背斜的核心^[5].

参考文献

^ Roberts, D.G. and Bally, A.W (editors) (2012). Regional Geology and Tectonics: Phanerozoic Passive Margins, Cratonic Basins and Global Tectonic Maps – Volume 1. Amsterdam: Elsevier. pp. 20–21. ISBN 978-0-444-56357-6. [
^ McGeary. D and C. C. Plummer (1994) Physical Geology: Earth revealed, Wm . C. Brown Publishers, Dubuque, p.475-476 ISBN 0-697-12687-0 [2]
^ Vendeville, B. C. and M. P. A. Jackson (1992b). The rise of diapirs during thin-skinned extension. Marine and Petroleum Geology, 9: 331-353
^ Stewart, S. A., 2007, Salt tectonics in the North Sea Basin: a structural style template for seismic interpreters, Special Publication of the Geological Society, London, 272, 361-396
^ Millán-Garrido, H. (2004). "Geometry and kinematics of compressional growth structures and diapirs in the La Popa basin of northeast Mexico: Insights from sequential restoration of a regional cross section and three-dimensional analysis". Tectonics. 23 (5). doi:10.1029/2003TC001540

[”Roberts”-1] Roberts, D.G. and Bally, A.W (editors) (2012). Regional Geology and Tectonics: Phanerozoic Passive Margins, Cratonic Basins and Global Tectonic Maps – Volume 1. Amsterdam: Elsevier. pp. 20–21. ISBN 978-0-444-56357-6. [

[”McGeary”-2] McGeary. D and C. C. Plummer (1994) Physical Geology: Earth revealed, Wm . C. Brown Publishers, Dubuque, p.475-476 ISBN 0-697-12687-0 [2]

[”Vendeville”-3] Vendeville, B. C. and M. P. A. Jackson (1992b). The rise of diapirs during thin-skinned extension. Marine and Petroleum Geology, 9: 331-353

[”Stewart,”-4] Stewart, S. A., 2007, Salt tectonics in the North Sea Basin: a structural style template for seismic interpreters, Special Publication of the Geological Society, London, 272, 361-396

[”Millán”-5] Millán-Garrido, H. (2004). "Geometry and kinematics of compressional growth structures and diapirs in the La Popa basin of northeast Mexico: Insights from sequential restoration of a regional cross section and three-dimensional analysis". Tectonics. 23 (5). doi:10.1029/2003TC001540

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