Mudboil and ice-wedge dynamics investigated by electrical resistivity tomography, ground temperatures and surface movements in Svalbard
Mudboil and ice-wedge dynamics investigated by electrical resistivity tomography, ground temperatures and surface movements in Svalbard
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通过电阻率断层扫描、地面温度和斯瓦尔巴群岛表面运动研究泥浆和冰楔动力学
DOI：
10.1111/j.1468-0459.2012.00470.x
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发表时间：
2012
期刊：
影响因子：
--
通讯作者：
H.H
中科院分区：
文献类型：
--
作者：
Watanabe;T.;Matsuoka;N. and Christiansen;H.H
北极苔原表面主要是由各种图案的地面形式。虽然大量的研究已经描述了形态，结构和过程的图案地面，很少有监测详细的图案地面动态和地下环境连续。我们应用电阻率层析成像（ERT）来了解斯瓦尔巴特群岛两种类型的图案化地面，冰楔多边形和泥沸的近地表条件，其中与永久冻土相关的冰缘过程被集中监测。自动监测显示表面运动的特点是每年的循环，冻胀和融化的沉降，其数量和速度的影响，冰分离的强度。ERT的时间序列显示：（1）一个清晰的电阻率边界界定了活动层的深度，（2）由热水文动力学控制的电阻率的季节性变化，（3）反映夏季干燥和冬季强烈冰分离的电阻率的空间变化。这些结果表明，ERT是一种有用的补充技术，用于监测冰缘图案地面站点的活动层深度和近地表水文条件，其中自动土壤热和水分测量有限。
Arctic tundra surfaces are dominated by a variety of patterned ground forms. Whereas a large number of studies have described morphology, structure and processes of patterned ground, few have monitored detailed patterned ground dynamics and subsurface environments continuously. We applied electrical resistivity tomography (ERT) to understand near‐surface conditions of two types of patterned ground, ice‐wedge polygons and mudboils in Svalbard, where periglacial processes associated with permafrost are intensively monitored. Automated monitoring shows surface movement characterized by annual cycles of frost heave and thaw settlement, the amounts and rates of which are influenced by the intensity of ice segregation. A time series of ERT shows (1) a distinct resistivity boundary delimiting the active‐layer depth, (2) seasonal variation in resistivity controlled by thermo‐hydrological dynamics and (3) spatial variation in resistivity reflecting desiccation in summer and intensive ice segregation in winter. These results demonstrate ERT as a useful complementary technique for monitoring active‐layer depths and near‐surface hydrological conditions at periglacial patterned ground sites, where automated soil thermal and moisture measurements are limited.