Study on pore structure characteristics of sea ice based on CT observation

Wang Qingkai; Xu Zhenghong; Chen Shijie; Li Zhijun; Lu Peng

doi:10.12284/hyxb2024103

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Wang Qingkai，Xu Zhenghong，Chen Shijie, et al. Study on pore structure characteristics of sea ice based on CT observation[J]. Haiyang Xuebao，2024, 46(10)：1–11 doi: 10.12284/hyxb2024103

Citation:

Wang Qingkai，Xu Zhenghong，Chen Shijie, et al. Study on pore structure characteristics of sea ice based on CT observation[J]. Haiyang Xuebao，2024, 46(10)：1–11 doi: 10.12284/hyxb2024103

Citation:

Wang Qingkai，Xu Zhenghong，Chen Shijie, et al. Study on pore structure characteristics of sea ice based on CT observation[J]. Haiyang Xuebao，2024, 46(10)：1–11 doi: 10.12284/hyxb2024103

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Study on pore structure characteristics of sea ice based on CT observation

doi: 10.12284/hyxb2024103

1.
State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology, Dalian 116024, China
2.
State Key Laboratory of Frozen Soil Engineering, Northwest Institute of Eco-Environment and Resource, Chinese Academy of Sciences, Lanzhou 730000, China

Received Date: 2024-05-24
Rev Recd Date: 2024-08-13

Available Online: 2024-09-25

Abstract

Abstract

Pore structure is an important mesoscopic feature of sea ice affecting its mechanical properties. In order to investigate the mesoscopic structure of melting sea ice, a sea ice block was collected during severe ice period in the Bohai Sea. The ice block was put in a low temperature environment (−1.0℃) for 48 h, which was then observed using a CT scanner. The thresholds of CT values among gas, ice, and brine were set to −310 HU and −30 HU for segmentation of the CT image, respectively. The gas and brine inclusions were able to be identified in the CT image, and the two-dimensional morphological characteristics of the pores in ice were analyzed. On the basis of image segmentation, the three-dimensional reconstruction of the ice pores was carried out, and the three-dimensional morphological characteristics of the pores were analyzed. It was found that along the ice thickness, the gas area fraction was 5.00%～35.93%, and the brine distribution was discontinuous with maximum area fraction of 0.06%. The cross-sectional shape of the gas and brine pores parallel to the ice surface was approximately circular, with a roundness more than 0.60. The equivalent circle diameter of gas pore was 1.1～3.2 mm, and that of brine was 0.2～2.0 mm. The equivalent circle diameter of pores was positively correlated with the area fraction and negatively correlated with the roundness. In terms of three-dimensional structure, 4 types of gas pores were divided according to sphericity (R_sph) into coronary pores (R_sph ≤ 0.25), irregular pores (0.25 < R_sph ≤ 0.45), strip pores (0.45 < R_sph ≤ 0.60), and spherical bubbles (0.60 < R_sph ≤ 1.00). The coronary pore was the largest (average volume (11522.8 ± 5610.2) mm³) with smallest amount, and the spherical bubble was the smallest (average diameter (2.0 ± 1.1) mm) with the largest amount. The brine pores were divided into brine channels (0.45 < R_sph ≤ 0.60) and brine cells (0.60 < R_sph ≤ 1.00). The average length of the brine channel was (17.1 ± 12.1) mm, and the average diameter of the brine cell was (1.5 ± 0.9) mm. The amount of brine channels was less, but the volume proportion was comparable to that of brine cells.
- sea ice,
- pore,
- structure characteristics,
- CT scanning,
- 3D reconstruction

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References(23)

References

[1]	Vancoppenolle M, Madec G, Thomas M, et al. Thermodynamics of sea ice phase composition revisited[J]. Journal of Geophysical Research: Oceans, 2019, 124(1): 615−634. doi: 10.1029/2018JC014611
[2]	Nicolaus M, Perovich D K, Spreen G, et al. Overview of the MOSAiC expedition: Snow and sea ice[J]. Elementa: Science of the Anthropocene, 2022, 10(1): 000046. doi: 10.1525/elementa.2021.000046
[3]	Wang Q, Lu P, Leppäranta M, et al. Physical properties of summer sea ice in the Pacific sector of the Arctic during 2008-2018[J]. Journal of Geophysical Research: Oceans, 2020, 125(9): e2020JC016371. doi: 10.1029/2020JC016371
[4]	Moslet P O. Field testing of uniaxial compression strength of columnar sea ice[J]. Cold Regions Science and Technology, 2007, 48(1): 1−14. doi: 10.1016/j.coldregions.2006.08.025
[5]	Wang Qingkai, Li Zhaoquan, Lu Peng, et al. Flexural and compressive strength of the landfast sea ice in the Prydz Bay, East Antarctic[J]. The Cryosphere, 2022, 16(5): 1941−1961. doi: 10.5194/tc-16-1941-2022
[6]	Hectors K, De Waele W. Influence of weld geometry on stress concentration factor distributions in tubular joints[J]. Journal of Constructional Steel Research, 2021, 176: 106376. doi: 10.1016/j.jcsr.2020.106376
[7]	Cox G F N, Weeks W F. Equations for determining the gas and brine volumes in sea-ice samples[J]. Journal of Glaciology, 1983, 29(102): 306−316. doi: 10.3189/S0022143000008364
[8]	Leppäranta M, Manninen T. The brine and gas content of sea ice with attention to low salinities and high temperatures[R]. Helsinki: Finnish Institute of Marine Research, 1988.
[9]	Cole D M, Eicken H, Frey K, et al. Observations of banding in first-year Arctic sea ice[J]. Journal of Geophysical Research: Oceans, 2004, 109(C8): C08012.
[10]	Light B, Maykut G A, Grenfell T C. Effects of temperature on the microstructure of first-year Arctic sea ice[J]. Journal of Geophysical Research: Oceans, 2003, 108(C2): 3051.
[11]	李志军, 康建成. 北极生长的多年海冰晶体结构分析[J]. 冰川冻土, 2001, 23(4): 383−388. Li Zhijun, Kang Jiancheng. Crystals and fabrics of an Arctic multi-year ice sample[J]. Journal of Glaciology and Geocryology, 2001, 23(4): 383−388.
[12]	Kawamura T. Observations of the internal structure of sea ice by X ray computed tomography[J]. Journal of Geophysical Research: Oceans, 1988, 93(C3): 2343−2350. doi: 10.1029/JC093iC03p02343
[13]	Golden K M, Eicken H, Heaton A L, et al. Thermal evolution of permeability and microstructure in sea ice[J]. Geophysical Research Letters, 2007, 34(16): L16501.
[14]	Pringle D J, Miner J E, Eicken H, et al. Pore space percolation in sea ice single crystals[J]. Journal of Geophysical Research: Oceans, 2009, 114(C12): C12017.
[15]	Crabeck O, Galley R, Delille B, et al. Imaging air volume fraction in sea ice using non-destructive X-ray tomography[J]. The Cryosphere, 2016, 10(3): 1125−1145. doi: 10.5194/tc-10-1125-2016
[16]	Oggier M, Eicken H, Wilkinson J, et al. Crude oil migration in sea-ice: laboratory studies of constraints on oil mobilization and seasonal evolution[J]. Cold Regions Science and Technology, 2020, 174: 102924. doi: 10.1016/j.coldregions.2019.102924
[17]	Maus S, Huthwelker T, Enzmann F, et al. Synchrotron-based X-ray micro-tomography: insights into sea ice microstructure[C]//Proceedings of the Sixth Workshop on Baltic Sea Ice Climate. Helsinki, Finland: University of Helsinki, 2009.
[18]	Obbard R W, Troderman G, Baker I. Imaging brine and air inclusions in sea ice using micro-X-ray computed tomography[J]. Journal of Glaciology, 2009, 55(194): 1113−1115. doi: 10.3189/002214309790794814
[19]	Lieb-Lappen R M, Golden E J, Obbard R W. Metrics for interpreting the microstructure of sea ice using X-ray micro-computed tomography[J]. Cold Regions Science and Technology, 2017, 138: 24−35. doi: 10.1016/j.coldregions.2017.03.001
[20]	Salomon M L, Maus S, Petrich C. Microstructure evolution of young sea ice from a Svalbard fjord using micro-CT analysis[J]. Journal of Glaciology, 2022, 68(269): 571−590. doi: 10.1017/jog.2021.119
[21]	Maus S, Schneebeli M, Wiegmann A. An X-ray micro-tomographic study of the pore space, permeability and percolation threshold of young sea ice[J]. The Cryosphere, 2021, 15(8): 4047−4072. doi: 10.5194/tc-15-4047-2021
[22]	蒲毅彬, 李志军. 海冰的CT扫描和分析计算[C]//中国地理学会冰川冻土分会. 第五届全国冰川冻土学大会论文集(上册). 兰州: 甘肃文化出版社, 1996: 586−590. Pu Yibin, Li Zhijun. CT scanning and calculation analysis of sea ice[C]//Glacier and Frozen Soil Branch of the Chinese Geographical Society. Proceedings of the 5th National Conference on Glaciology and Permafrost (Volume I). Lanzhou: Gansu Culture Publishing House, 1996: 586−590. (查阅网上资料, 未找到本条文献英文翻译, 请确认)
[23]	Li Zhijun, Pu Yibin. Some applications of computerized tomography scanner to sea ice[C]//Proceedings of the 12th International Offshore and Polar Engineering Conference. Kitakyushu, Japan, 2002. (查阅网上资料, 未找到本条文献出版社信息, 请确认)