Hydrogeochemical data are used to better understand recharge dynamics and to support a hydrogeological conceptual model in a 2-km² watershed in a discontinuous permafrost zone in Nunavik, Canada. The watershed contains an upper (surficial) and lower aquifer within Quaternary deposits, above and below a marine silt layer containing ice-rich permafrost mounds. The analysis is based on water samples from precipitation, groundwater monitoring wells, ground ice in permafrost mounds, thermokarst lakes and a perennial stream. Groundwater geochemistry in both aquifers reflects young, poorly evolved waters, with mainly Ca-HCO₃ water types and low mineralisation ranging from 11 to 158 mg/L total dissolved solids (TDS), implying short pathways and rapid travel times of a year or less. While relatively low, TDS signatures in groundwater and surface water show increasing values downgradient. Groundwater isotope values (δ¹⁸O_H2O and δ²H_H2O) are often strongly influenced by snowmelt, while those of thermokarst lakes show evidence of evaporation. Recharge along the cuesta contributes to a transverse component of groundwater flow within the valley with higher TDS and δ¹³C_DIC values influenced by open-system weathering. Even where permafrost-free, the marine silt unit has a strong confining effect and plays a more important role on recharge dynamics than the discontinuous permafrost. Nevertheless, the vulnerability of these types of hydrogeological aquifer systems is expected to increase due to rapid recharge dynamics associated with the gradual loss of the confining effect of permafrost. This hydrogeochemical data set will be useful as a baseline to document impacts of permafrost degradation on the hydrogeological system.

水文地球化学数据可用于更好地理解补给动力学，并支持加拿大努纳维克不连续多年冻土带2 km ²流域中的水文地质概念模型。该分水岭在第四纪沉积层内，海底淤泥层之上和之下的上部（表面）含水层和下部含水层，这些淤泥层含有富含冰的多年冻土丘。该分析基于降水，地下水监测井，多年冻土丘，地热喀斯特湖和多年生河流中的地下冰中的水样。两种含水层中的地下水地球化学反映了发育较差的年轻水域，主要是Ca-HCO ₃水类型和低矿化度，总溶解固体（TDS）范围从11到158 mg / L，这意味着路径短且旅行时间短于一年或更短。尽管相对较低，但地下水和地表水中的TDS签名显示出逐渐降低的值。地下水同位素值（δ ¹⁸ ö _H2O和δ ² ħ _H2O）常常强烈影响的融雪，而热喀斯特湖泊的显示蒸发的证据。充值沿奎斯塔有助于谷内地下水流的横向分量具有较高的TDS和δ ¹³ C ^ _DIC值受开放系统的天气影响。即使在没有多年冻土的地方，海洋淤泥单元也具有不连续的永久冻土作用，并且在补给动力学方面具有更重要的作用。然而，由于与永久冻土的封闭作用逐渐丧失有关的快速补给动力学，预计这些类型的水文地质含水层系统的脆弱性将增加。该水文地球化学数据集将用作记录多年冻土退化对水文地质系统影响的基准。