Distribuution and geomorphic significance of mountain permafrost in the Japanese Alps

日本阿尔卑斯山脉多年冻土的分布及其地貌意义

• 批准号: 08680184
• 负责人: MATSUOKA Norikazu
• 金额: $ 1.73万
• 依托单位: University of Tsukuba
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08680184/
• 关键词: permafrost; periglacial; rock glacier; mass movements; ground temperature; monitoring

The distribution of mountain permafrost was estimated in two regions of the Japanese Alps, by means of field monitoring of ground temperature and topographic analyzes of rock glaciers that indicate permafrost conditions. Field observations were also undertaken in an attempt to evaluate contemporary geomorphic processes associated with mountain permafrost. The two-year study led to the following conclusions.1.Thermal observations indicate that the rock glacier in the Kuranosuke cirque, northern Japanese Alps, is underlain by permafrost and, hence, the rock glacier has not yet been fossilized. Permafrost may also be present in the north-facing rockwalls above 3000m ASL in the Ainodake region, southern Japanese Alps.2.The topographic analysis demonstrates that large part of the landforms which have previously been identified as the Late Glacial moraines are, in fact, relict rock glaciers, suggesting the past permafrost environments widespread over Japanese Alps. These rock glaciers have the lobate or tongue-shaped form, ridge-furrow topography, highest outermost ridge and subsided top surface, all of which are observed on the typical fossilized rock glaciers in the Swiss Alps.3.Three kinds of freeze-thaw cycles are proposed in light of temporal scales. They are diurnal, annual and millennial cycles. The presence of permafrost rarely affects diurnal freeze-thaw action, but it is essential in controlling slope processes occurring at the annual basis. The third type, millennial freeze-thaw action, reflects directly the growth and decay of permafrost, possibly producing a large-scale gemorphic changes including cliff falls and debris flows on steep mountain slopes. Recent global warming gives attention to future predictions of natural hazards originating from the thawing phase of a millennial cycle.

在日本阿尔卑斯山的两个地区的山地冻土的分布估计，通过地面温度的实地监测和地形分析的岩石冰川，表明冻土条件。还进行了实地观测，试图评价与山区永久冻土有关的当代地貌过程。经过两年的研究，得出以下结论：1.热观测表明，日本阿尔卑斯山北方仓之助冰斗的岩石冰川下伏于永久冻土，因此，岩石冰川尚未被冻融。日本阿尔卑斯山南部爱之岳地区海拔3000 m以上的北向岩壁也可能存在多年冻土。2.地形分析表明，以前被认为是晚冰期冰碛的地貌大部分实际上是残余的岩石冰川，表明过去的多年冻土环境在日本阿尔卑斯山广泛存在。这些岩石冰川具有叶状或舌形形态、山脊-犁沟地形、最高的最外山脊和下沉的顶面，所有这些都在瑞士阿尔卑斯山典型的化石岩石冰川上观察到。3.根据时间尺度，提出了三种冻融循环。它们是日周期、年周期和千年周期。多年冻土的存在很少影响昼夜冻融作用，但它是必不可少的控制斜坡过程发生在每年的基础上。第三类是千年冻融作用，直接反映了多年冻土的生长和衰变，可能产生大规模的地貌变化，包括陡坡上的悬崖福尔斯和泥石流。最近的全球变暖使人们注意到对千年周期的解冻阶段所产生的自然灾害的未来预测。

项目成果

松岡 憲知: "岩石氷河-氷河説と周氷河説-" 地学雑誌. (印刷中). (1998)

Kentomo Matsuoka：“岩石冰川 - 冰川理论和冰缘理论”地质杂志（1998 年出版）。

Norikazu, Matsuoka: "Soil moisture variability in relation to diurnal frost heaving on Japanese high mountain slopes" Permafrost and Periglacial Processes. 7(2). 139-151 (1996)

Norikazu，Matsuoka：“土壤湿度变化与日本高山斜坡日间冻胀的关系”永久冻土和冰缘过程。

Norikazu Matsuoka et al.: "The role of diurnal,annual and millennial freeze-thaw cycles in controlling alpine slope instability" proceedings of the 7th International Conference on Permafrost. (印刷中). (1998)

Norikazu Matsuoka 等人：“昼夜、年度和千年冻融循环在控制高山斜坡不稳定中的作用”第七届国际永久冻土会议记录（1998 年）。

Matsuoka, N.: "The relationship between frost heave and downslope soil movement : field measurements in the Japanese Alps" Permafrost and Periglacial Processes. (in press). (1998)

Matsuoka, N.：“冻胀与下坡土壤运动之间的关系：日本阿尔卑斯山的现场测量”永久冻土和冰缘过程。

Norikazu Matsuoka: "Soil moisture variability in relation to diurnal frost heaving on Japanese higy mountain slopes" Permafrost and Periglacial Processes. 7(2). 139-151 (1996)

Norikazu Matsuoka：“土壤湿度变化与日本高山坡上的日霜冻有关”永久冻土和冰缘过程。