Rock glacier permafrost in the Central Andes of Argentina (PermArg): regional distribution - ice content - hydrological significance

岩石冰川是安第斯山脉中部主要的冰缘地貌。在永久冻土层和季节性冻结的活动层内，岩石冰川可能储存了大量的水。与冰川相反，这些水库的动态如何影响这些地区的水文，在很大程度上仍然不清楚。由于岩石冰川在安第斯山脉的这一部分大量存在，其水文意义引发了一场激烈的科学辩论。阿根廷中部安第斯山脉位于30 - 33°S之间，是填补这一研究空白的理想地点，因为该研究区域可能是世界上岩石冰川密度最高的地区，农业严重依赖融水，而且莫雷纳斯科罗拉多和多斯伦瓜斯岩石冰川已经成为以前永久冻土研究的主题。拟议的研究项目的目的是：(i)确定气候、地形和岩性如何控制30至33°S之间阿根廷安第斯山脉中部岩石冰川的空间分布；（ii）量化两个本地岩石冰川的活跃层沉积物的季节性储水量和释放水量，以及永久冻土层的冰含量；(3)估算整个研究区岩石冰川多年冻土的储水量。为了实现这些目标，我们将结合使用现场地球物理（电阻率层析成像（ERT）、折射地震层析成像（RST）、探地雷达（GPR））和四相模型来估计莫伦纳斯科罗拉多和多斯伦瓜斯岩石冰川的活跃层和永久冻土层的体积冰含量。当地调查将由沉积物性质的直接观察、热监测和实地测绘加以补充。将通过编制和分析基于遥感的清单来研究岩石冰川分布的区域控制，该清单将进一步作为基于现场经验数据的岩石冰川储水能力一阶量化的基础。这使我们能够对安第斯岩石冰川永久冻土的水文意义得出定量结论。

Rock glaciers are the predominant periglacial landform in the Central Andes. Within the permafrost body and the seasonally frozen active layer, rock glaciers potentially store large amounts of water. As opposed to ice glaciers, it remains largely unclear how the dynamics of these water reservoirs affect the hydrology of these regions. Due to their large abundance in this part of the Andes, the hydrological significance of rock glaciers has triggered a strong scientific debate. Therefore local studies assessing water storage capacities of rock glaciers are urgently needed The Central Andes of Argentina between 30 and 33°S represent an ideal location to close this research gap, because the study area features probably the highest rock glacier concentration in the world, the agriculture critically depends on melt water, and Morenas Coloradas and Dos Lenguas rock glaciers have been subject of previous permafrost investigations. The aims of the proposed research project are (i) to determine how climate, topography and lithology control the spatial distribution of rock glaciers in the Central Andes of Argentina between 30 and 33°S; (ii) to quantify seasonally stored and released water equivalents from active layer sediments as well as ice contents of permafrost bodies in two local rock glaciers; and (iii) to estimate water storage capacities of rock glacier permafrost in the whole study area. To achieve these objectives we will use a combination of field geophysics (electrical resistivity tomography (ERT), refraction seismic tomography (RST), ground penetrating radar (GPR)) and four phase modeling to estimate the volumetric ice contents of the active layer and the permafrost bodies of the Morenas Coloradas and Dos Lenguas rock glaciers. Local investigations will be complemented by direct observations of sediment properties, thermal monitoring and field based mapping. Regional controls of the rock glacier distribution will be investigated by compiling and analyzing a remote sensing based inventory that further serves as basis for a first order quantification of the water storage capacities of rock glaciers based on empirical field data. This enables us to draw quantitative conclusions on the hydrological significance of Andean rock glacier permafrost.