Modelling borehole flows from Distributed Temperature Sensing data to monitor groundwater dynamics in fractured media

Hydrological and geological controls for the joint evolution of dissolved oxygen and iron in crystalline rocks

“…Hence, the depth of the reservoir of the groundwater circulating in a fracture (Depth proxy ) was calculated as: after (Pouladi et al, 2021).…”

“…The average value for T rech has been estimated to be 12.2±0.41 • C as deduced from temperature time-series (from 2002 to 2018) recorded at the weather station in the Ploemeur CZO. On the other hand, previous works suggest that the G G of the Ploemeur site ranges between 0.016 and 0.013 Pouladi et al, 2021;Klepikova et al, 2011) and for this work we considered the most recent estimate of 0.013 • C.m −1 after Pouladi et al (2021).…”

Estimation of Groundwater Flow Rate by an Actively Heated Fiber Optics Based Thermal Response Test in a Grouted Borehole

“…The concept of ATRT has become popular for evaluating groundwater flow in porous media and fractures (Bakker et al., 2015; Bense et al., 2016; des Tombe et al., 2019; Munn et al., 2020; Pouladi et al., 2021; Selker & Selker, 2018), as it provides distributed measurements. There are different methods for establishing the relationship between the groundwater flow rate and the temperature response curve of a linear heat source.…”

Monitoring groundwater fluxes variations through active-DTS measurements

“…For instance, in coastal sediments, transient flow conditions influence the ecosystem productivity and its biogeochemistry (Robinson et al, 2018;Taniguchi et al, 2019), while temporal variabilities in groundwater / surface water interactions induce biogeochemical hot moments within the hyporheic zone (McClain et al 2003;Boano et al 2014;Lewandowski et al 2019). The monitoring of groundwater fluxes at different depths during a pumping test would be also very useful to image flow variability and sub-surface heterogeneities (Pouladi et al 2021b).…”

“…The temporal and spatial variability of groundwater fluxes depends on many natural or maninduced mechanisms which induce fluctuations in groundwater levels at different time scales (Freeze and Cherry 1979;Jiménez-Martínez et al 2013). Short-lived fluctuations can typically be observed during the recharge of highly heterogeneous systems (Ghasemizadeh et al 2012;Pouladi et al 2021b) while diurnal variations can occur for instance as the result of evapotranspiration, atmospheric pressure effects or else tidal effects (Ataie-Ashtiani et al 2001;Paepen et al 2020;LeRoux et al 2021). Groundwater recharge through infiltration (Freeze, 1974) and bank-storage effects near streams (Winter et al 1998;Boano et al 2013;Harvey and Gooseff 2015) can induce seasonal fluctuations in groundwater levels, while climate changes and many human activities, such as groundwater pumping, artificial recharge, agricultural irrigation and drainage or else geotechnical drainage, induce short-term as well as long-term fluctuations of groundwater levels (Freeze and Cherry 1979;Hancock 2002;de Graaf et al 2019).…”