DOI: 10.1002/2017JF004343
Scopus记录号: 2-s2.0-85046698900
论文题名: Detection of Ice Wedge Cracking in Permafrost Using Miniature Accelerometers
作者: O'Neill H.B. ; Christiansen H.H.
刊名: Journal of Geophysical Research: Earth Surface
ISSN: 21699003
出版年: 2018
卷: 123, 期: 4 起始页码: 642
结束页码: 657
语种: 英语
英文关键词: cryoseismology
; ice wedges
; permafrost
; thermal contraction cracking
Scopus关键词: accelerometer
; crack propagation
; detection method
; permafrost
; seismology
; strength
; tensile stress
; Adventdalen
; Arctic
; Spitsbergen
; Svalbard
; Svalbard and Jan Mayen
英文摘要: Determining the exact timing of ice wedge cracking in permafrost is challenging. Five miniature accelerometers were installed near the ground surface in the trough of a primary ice wedge within a network of low-centered polygons in Adventdalen, Svalbard, to test whether these instruments could be used to detect dynamics of thermal contraction cracking. Data from 2003 to 2013 were analyzed to characterize cryoseismic signals in the ice wedge trough. High-magnitude accelerations (from 5 g to at least 100 g) were typically registered in late winter, when the top of permafrost had cooled to about −10°C; these likely correspond to ice wedge cracking in permafrost. Tensile stresses calculated from temperatures measured in the ice wedge trough are near laboratory strengths reported for ice and mineral active layer sediments, supporting the interpretation that large accelerations are caused by thermal contraction cracking. Lower magnitude accelerations occurred throughout the freezing season, usually coinciding with rapid cooling at the ground surface. These small accelerations may be associated with (i) the initiation of small cracks in the active layer of the trough or (ii) the horizontal and vertical propagation of existing ice wedge cracks. The results of this investigation indicate that miniature accelerometers are an effective, inexpensive, and simple method to determine the timing of ice wedge cracking and rates of crack propagation along ice wedge troughs. ©2018. American Geophysical Union. All Rights Reserved.
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资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/114234
Appears in Collections: 气候减缓与适应
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作者单位: Department of Arctic Geology, The University Centre in Svalbard, Longyearbyen, Norway; Geological Survey of Canada, Ottawa, ON, Canada
Recommended Citation:
O'Neill H.B.,Christiansen H.H.. Detection of Ice Wedge Cracking in Permafrost Using Miniature Accelerometers[J]. Journal of Geophysical Research: Earth Surface,2018-01-01,123(4)