苔原内的冰透镜形成

在北极苔原中,由于周期性的冰透镜形成而造成Pingo
在寒冷气候中形成冰透镜导致冰冻胀
Ice Lens formation within tundra.
冰透镜生长在冰积层和冰川冰下的基岩中的冰透镜

冰解离(英语:Ice segregation) 是由冰透镜的形成而产生的地质侵蚀现象,冰透镜是当水分在土壤或岩石中扩散时, 在局部区域积聚时,若温度降低形成的冰体。冰的生长需要供水,由土壤中的毛细作用将水输送。由于上覆土壤的重量,限制了冰的向上生长,就在土壤内形成一个透镜状冰区域。土壤必须有足够的孔隙度让水性通过毛细管作用上升,但孔隙度又不能太高到破坏毛细管的连续性[1][2]。 冰最初聚集在孔隙或裂缝中,只要水分能继续补充,温度低于冰点,冰就会继续聚集并成长成透镜体,将土壤或岩石楔开[3]。冰透镜平行于地表生长,在土壤或岩石中深达几厘米到几分米(英寸到英尺)。 研究表明,冰解离(ice segregation)比冻融能更有效造成岩石的破裂[4] [5]

冰透镜的形成由冻胀引起土壤隆起和基岩断裂的关键作用,是在寒冷地区的主要风化作用。冻胀会产生岩石碎片,并改变景观。尽管在冰缘地区(高山、亚极地和极地)的岩石破裂通常归因于孔隙和裂缝中的水的冻结和体积膨胀,但大部分冻胀和基岩破裂是由冰解离和冰透镜生长引起的[6]冻胀是指当水向上进入到土壤中的冰冻温度深度时,就结冰引起土壤向上膨胀[7]

参考文献

  1. ^ Taber, Stephen (1929). "Frost Heaving" (PDF). Journal of Geology. 37 (5): 428–461. Bibcode:1929JG.....37..428T. doi:10.1086/623637. S2CID 224836578. Archived from the original on 2013-04-08. Retrieved 2010-03-24.
  2. ^ Rempel, A.W.; Wettlaufer, J.S.; Worster, M.G. (2001). "Interfacial Premelting and the Thermomolecular Force: Thermodynamic Buoyancy". Physical Review Letters. 87 (8): 088501. Bibcode:2001PhRvL..87h8501R. doi:10.1103/PhysRevLett.87.088501. PMID 11497990.
  3. ^ Walder, Joseph; Hallet, Bernard (March 1985). "A theoretical model of the fracture of rock during freezing". Geological Society of America Bulletin. Geological Society of America. 96 (3): 336–346. Bibcode:1985GSAB...96..336W. doi:10.1130/0016-7606(1985)96<336:ATMOTF>2.0.CO;2.
  4. ^ "Periglacial weathering and headwall erosion in cirque glacier bergschrunds"; Johnny W. Sanders, Kurt M. Cuffey, Jeffrey R. Moore, Kelly R. MacGregor and Jeffrey L. Kavanaugh; Geology; July 18, 2012, doi:10.1130/G33330.1
  5. ^ Rempel, A.W. (2007). "Formation of ice lenses and frost heave". Journal of Geophysical Research. American Geophysical Union. 112 (F02S21): F02S21. Bibcode:2007JGRF..11202S21R
  6. ^ Murton, Julian B.; Peterson, Rorik; Ozouf, Jean-Claude (17 November 2006). "Bedrock Fracture by Ice Segregation in Cold Regions". Science. 314 (5802): 1127–1129. Bibcode:2006Sci...314.1127M. doi:10.1126/science.1132127. PMID 17110573. S2CID 37639112
  7. ^ Peterson, R. A.; Krantz , W. B. (2008). "Differential frost heave model for patterned ground formation: Corroboration with observations along a North American arctic transect". Journal of Geophysical Research. American Geophysical Union. 113: G03S04. Bibcode:2008JGRG..11303S04P. doi:10.1029/2007JG000559.