The progressive electrification of the building conditioning sector in recent years has greatly contributed to reducing greenhouse gas emissions by using renewable energy sources, particularly shallow geothermal energy. This energy can be exploited through open and closed shallow geothermal systems (SGS), and their performances greatly depend on the ground/groundwater temperature, which can be affected by both natural and anthropogenic phenomena. The present study proposes an approach to characterize aquifers affected by high SGS exploitation (not simulated in this work). Characterization of the potential hydro/thermogeological natural state is necessary to understand the regional flow and heat transport, and to identify local thermal anomalies. Passive microseismic and groundwater monitoring were used to assess the shape and thermal status of the aquifer; numerical modeling in both steady-state and transient conditions allowed understanding of the flow and heat transport patterns. Two significant thermal anomalies were detected in a fluvio-glacial aquifer in southern Switzerland, one created by river water exfiltration and one of anthropogenic nature. A favorable time lag of 110 days between river and groundwater temperature and an urban hot plume produced by underground structures were observed. These thermal anomalies greatly affect the local thermal status of the aquifer and consequently the design and efficiency of current and future SGS. Results show that the correct characterization of the natural thermo-hydrogeological status of an aquifer is a fundamental basis for determining the impact of boundary conditions and to provide initial conditions required to perform reliable local thermal sustainability assessments, especially where high SGS exploitation occurs.

近年来，建筑空调行业的逐步电气化通过使用可再生能源，特别是浅层地热能，极大地减少了温室气体排放。这种能量可以通过开放和封闭的浅层地热系统 (SGS) 来开发，它们的性能在很大程度上取决于地面/地下水温度，这可能会受到自然和人为现象的影响。本研究提出了一种表征受高 SGS 开采影响的含水层的方法（在本工作中未模拟）。潜在水文/热地质自然状态的表征对于了解区域流动和热传输以及识别局部热异常是必要的。被动微地震和地下水监测被用来评估含水层的形状和热状态；稳态和瞬态条件下的数值模拟有助于了解流动和热传输模式。在瑞士南部的一个河流冰川含水层中发现了两种显着的热异常，一种是由河水渗漏造成的，另一种是人为造成的。观察到河流和地下水温度之间存在 110 天的有利时滞以及地下结构产生的城市热羽流。这些热异常极大地影响了含水层的局部热状态，从而影响了当前和未来 SGS 的设计和效率。