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    The dataset includes BLUM and long base tiltmeter data.

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    The dataset includes BLUM and long base tiltmeter data.

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    The vadose zone is the main host of surface and subsurface water exchange and has important implications for ecosystems functioning,climate sciences,geotechnical engineering,and water availability issues. Geophysics provides a means for investigating the subsurface in a non-invasive way and at larger spatial scales than conventional hydrological sensors. Time-lapse hydrogeophysical applications are especially useful for monitoring flow and water content dynamics. Largely dominated by electrical and electromagnetic methods,such applications increasingly rely on seismic methods as a complementary approach to describe the structure and behavior of the vadose zone. To further explore the applicability of active seismics to retrieve quantitative information about dynamic processes in near-surface time-lapse settings,we designed a controlled water infiltration experiment at the Ploemeur Hydrological Observatory (France) during which successive periods of infiltration were followed by surface-based seismic and electrical resistivity acquisitions. Water content was monitored throughout the experiment by means of sensors at different depths to relate the derived seismic and electrical properties to water saturation changes. We observe comparable trends in the electrical and seismic responses during the experiment,highlighting the utility of the seismic method to monitor hydrological processes and unsaturated flow. Moreover,petrophysical relationships seem promising in providing quantitative results.

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    This dataset includes vadose zone data (temperature,water content and suction) and flux tower data (air pressure,air specific humidity,air temperature,co2 flux,evapotranspiration,h2o flux,latent heat flux,wind direction,wind speed).

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    This dataset includes vadose zone data (temperature,water content and suction) and flux tower data (air pressure,air specific humidity,air temperature,co2 flux,evapotranspiration,h2o flux,latent heat flux,wind direction,wind speed).

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    This borehole hydrogeophysical logging data include optical imaging,acoustic logging,induction and electrical resistivity,natural and spectral gamma radioactivity,fiber optic measurements and multiparameter probe logs.

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    This borehole hydrogeophysical logging data include optical imaging,acoustic logging,induction and electrical resistivity,natural and spectral gamma radioactivity,fiber optic measurements and multiparameter probe logs.

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    Fractured aquifers are known to be very heterogeneous with complex flow path geometries. Their characterization and monitoring remain challenging despite the importance to better understand their behavior at all spatial and temporal scales. Heat and correspondingly temperature data have gained much interest in recent years and are often used as a tracer for characterizing groundwater flows. In the current work,a fast computer code is developed using Ramey and Hassan and Kabir analytical solutions which converts the temperature profile to the flow rate profile along the borehole. The method developed is validated through numerical simulations. A global sensitivity study recognizes the media thermal properties as the most influential parameters. For testing the method in the field,fiber-optic distributed temperature sensing (FO-DTS) data were used to monitor the dynamic behavior of fractured aquifers at the borehole scale at the Ploemeur-Guidel field site in Brittany,France. DTS data are used to infer the flow rates in the different sections of a fractured wellbore (flow profile) and calculate the contribution of each fracture to the total flow. DTS data were acquired for about three days in three different hydraulic conditions corresponding to two different ambient flow conditions and one pumping condition. Flow profiling using distributed temperature data matches satisfactorily with results from heat-pulse flow metering performed in parallel for cross-checking. Moreover,flow profiling reveals the daily variations of ambient flow in this fractured borehole. Furthermore,it shows that during ambient flowing conditions,shallow and deep fractures contribute roughly equally to the total flow while during the pumping condition,the deepest fractures contribute more to the total flow,suggesting a possible reorganization of flow and hydraulic heads depending on the hydraulic conditions. Thus,although the proposed method (DTS data and proposed framework) may be costlier and is based on indirect characterization through temperature measurements,it provides real-time monitoring of complex fracture interactions and recharge processes in fractured media. Thus,this method allows for a full analysis of the temporal behavior of the system with a simple and fast analytical model. Furthermore,thanks to its narrow width,DTS can be used and installed in boreholes for long-term monitoring while heat-pulse flow metering may lead to head losses in the borehole and may not be always possible depending on some borehole conditions. One of the limitations of the approach proposed is the proper knowledge of the thermal properties of media required to infer the flow rate from the temperature. Nevertheless,surface rate measurement can be useful to constrain these properties and reduce the flow profiling uncertainty. Thus,the method proposed appears to be an interesting and complementary method for characterizing borehole flows and groundwater dynamics in fractured media such as for instance,monitoring the recharge dynamic

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    This borehole hydrogeophysical logging data include optical imaging,acoustic logging,induction and electrical resistivity,natural and spectral gamma radioactivity,fiber optic measurements and multiparameter probe logs.

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    This borehole hydrogeophysical logging data include optical imaging,acoustic logging,induction and electrical resistivity,natural and spectral gamma radioactivity,fiber optic measurements and multiparameter probe logs.