Frederick D. Day-Lewis (Former Employee)
Science and Products
Filter Total Items: 93
Beware of spatial autocorrelation when applying machine learning algorithms to borehole geophysical logs
Although many of the algorithms now considered to be machine learning algorithms (MLAs) have existed for nearly a century (e.g., Rosenblatt 1958), interest in MLAs has recently increased exponentially for solving data-driven problems across a variety of fields due to the expanded availability of large, complex datasets that may be difficult to interrogate using other methods, increases in computin
Authors
Neil Terry, Carole D. Johnson, Frederick Day-Lewis, Beth L. Parker, Lee D. Slater
Characterizing physical properties of streambed interface sediments using in situ complex electrical conductivity measurements
Streambed sediment physical properties such as surface area, are difficult to quantify in situ but exert a high‐level control on a wide range of biogeochemical processes and sorption of contaminants. We introduce the use of complex electrical conductivity (CC) methods (also known as spectral induced polarization (SIP)) that measure both real and imaginary conductivity to non‐invasively and efficie
Authors
Cheng-Hui Wang, Martin A. Briggs, Frederick Day-Lewis, L. Slater
Experimental shifts of hydrologic residence time in a sandy urban stream sediment-water interface alter nitrate removal and nitrous oxide fluxes
The sediment–water interfaces (SWI) of streams serve as important biogeochemical hotspots in watersheds and contribute to whole-catchment reactive nitrogen budgets and water-quality conditions. Recently, the SWI has been identified as an important source of nitrous oxide (N2O) produced in streams, with SWI residence time among the principal controls on its production. Here, we conducted a series o
Authors
T. Hampton, J. Zarnetske, Martin A. Briggs, F. M. P. Dehkordy, K. Singha, Frederick Day-Lewis, Judson Harvey, S. R. Chowdhury, John W. Lane
Formation criteria for hyporheic anoxic microzones: Assessing interactions of hydraulics, nutrients and biofilms
Recent experimental studies have detected the presence of anoxic microzones in hyporheic sediments. These microzones are small‐scale anoxic pores, embedded within oxygen‐rich porous media and can act as anaerobic reaction sites producing reduction compounds such as nitrous oxide, a potent greenhouse gas. Microbes are a key control on nutrient transformation in hyporheic sediment, but their associa
Authors
S. R. Chowdhury, J. Zarnetske, M.S. Phanikumar, Martin A. Briggs, Frederick D. Day-Lewis, K. Singha
Geophysical mapping of plume discharge to surface water at a crude oil spill site: Inversion versus machine learning
The interpretation of geophysical survey results to answer hydrologic, engineering, and geologic questions is critical to diverse problems for management of water, energy, and mineral resources. Although geophysical images provide valuable qualitative insight into subsurface architecture and conditions, translating geophysical images into quantitative information (e.g., saturation, concentration,
Authors
Neil Terry, Frederick D. Day-Lewis, John W. Lane, Jared J. Trost, Barbara A. Bekins
Return flows from beaver ponds enhance floodplain-to-river metals exchange in alluvial mountain catchments
River to floodplain hydrologic connectivity is strongly enhanced by beaver- (Castor canadensis) engineered channel water diversions. The hydroecological impacts are wide ranging and generally positive, however, the hydrogeochemical characteristics of beaver-induced flowpaths have not been thoroughly examined. Using a suite of complementary ground- and drone-based heat tracing and remote sensing me
Authors
Martin Briggs, Cheng-Hui Wang, Frederick Day-Lewis, Kenneth H. Williams, Wenming Dong, John Lane
Residence time controls on the fate of nitrogen in flow‐through lakebed sediments
For many glacial lakes with highly permeable sediments, water exchange rates control hydrologic residence times within the sediment‐water interface (SWI) and the removal of reactive compounds such as nitrate, a common pollutant in lakes and groundwater. Here we conducted a series of focused tracer injection experiments in the upper 20 cm of the naturally downwelling SWI in a flow‐through lake on C
Authors
Tyler B. Hampton, Jay P. Zarentske, Martin A. Briggs, Kamini Singha, Judson W. Harvey, Frederick D. Day-Lewis, Farzaneh MahmoodPoor Dehkordy, John W. Lane
Multi-scale preferential flow processes in an urban streambed under variable hydraulic conditions
Spatially preferential flow processes occur at nested scales at the sediment-water interface (SWI), due in part to sediment heterogeneities, which may be enhanced in flashy urban streams with heavy road sand influence. However, several factors, including the flow-rate dependence of preferential hyporheic flow and discrete groundwater discharge zones are commonly overlooked in reach-scale models of
Authors
Farzaneh MahmoodPoor Dehkordy, Martin A. Briggs, Frederick D. Day-Lewis, Kamini Singha, Ashton Krajnovich, Tyler B. Hampton, Jay P. Zarnetske, Courtney R. Scruggs, Amvrossios C. Bagtzoglou
The dual‐domain porosity apparatus: Characterizing dual porosity at the sediment/water interface
The characterization of pore-space connectivity in porous media at the sediment/water interface is critical to understanding contaminant transport and reactive biogeochemical processes in zones of groundwater and surface-water exchange. Previous in situ studies of dual-domain (i.e.,
mobile/less-mobile porosity) studies have been limited to solute tracer injections at scales of meters to 100s
Authors
Courtney R. Scruggs, Martin A. Briggs, Frederick D. Day-Lewis, Dale D. Werkema, John W. Lane
DTSGUI: A python program to process and visualize fiber‐optic distributed temperature sensing data
Fiber‐optic distributed temperature sensing (FO‐DTS) has proven to be a transformative technology for the hydrologic sciences, with application to diverse problems including hyporheic exchange, groundwater/surface‐water interaction, fractured‐rock characterization, and cold regions hydrology. FO‐DTS produces large, complex, and information‐rich datasets. Despite the potential of FO‐DTS, adoption o
Authors
Marian M. Domanski, Daven Quinn, Frederick D. Day-Lewis, Martin A. Briggs, Dale D. Werkema, John W. Lane
Evaluating long-term patterns of decreasing groundwater discharge through a lake-bottom permeable reactive barrier
Identifying and quantifying groundwater exchange is critical when considering contaminant fate and transport at the groundwater/surface-water interface. In this paper, areally distributed temperature and point seepage measurements are used to efficiently assess spatial and temporal groundwater discharge patterns through a glacial-kettle lakebed area containing a zero-valent iron permeable reactive
Authors
Timothy D. McCobb, Martin A. Briggs, Denis R. LeBlanc, Frederick D. Day-Lewis, Carole D. Johnson
Direct observations of hydrologic exchange occurring with less‐mobile porosity and the development of anoxic microzones in sandy lakebed sediments
Quantifying coupled mobile/less‐mobile porosity dynamics is critical to the prediction of biogeochemical storage, release, and transformation processes in the zone where groundwater and surface water exchange. The recent development of fine‐scale geoelectrical monitoring paired with pore‐water sampling in groundwater systems enables direct characterization of hydrologic exchange between more‐ and
Authors
Martin A. Briggs, Frederick D. Day-Lewis, Farzaneh Mahmood Poor Dehkordy, Tyler B. Hampton, Jay P. Zarnetske, Courtney R. Scruggs, Kamini Singha, Judson W. Harvey, John W. Lane
Science and Products
Filter Total Items: 93
Beware of spatial autocorrelation when applying machine learning algorithms to borehole geophysical logs
Although many of the algorithms now considered to be machine learning algorithms (MLAs) have existed for nearly a century (e.g., Rosenblatt 1958), interest in MLAs has recently increased exponentially for solving data-driven problems across a variety of fields due to the expanded availability of large, complex datasets that may be difficult to interrogate using other methods, increases in computin
Authors
Neil Terry, Carole D. Johnson, Frederick Day-Lewis, Beth L. Parker, Lee D. Slater
Characterizing physical properties of streambed interface sediments using in situ complex electrical conductivity measurements
Streambed sediment physical properties such as surface area, are difficult to quantify in situ but exert a high‐level control on a wide range of biogeochemical processes and sorption of contaminants. We introduce the use of complex electrical conductivity (CC) methods (also known as spectral induced polarization (SIP)) that measure both real and imaginary conductivity to non‐invasively and efficie
Authors
Cheng-Hui Wang, Martin A. Briggs, Frederick Day-Lewis, L. Slater
Experimental shifts of hydrologic residence time in a sandy urban stream sediment-water interface alter nitrate removal and nitrous oxide fluxes
The sediment–water interfaces (SWI) of streams serve as important biogeochemical hotspots in watersheds and contribute to whole-catchment reactive nitrogen budgets and water-quality conditions. Recently, the SWI has been identified as an important source of nitrous oxide (N2O) produced in streams, with SWI residence time among the principal controls on its production. Here, we conducted a series o
Authors
T. Hampton, J. Zarnetske, Martin A. Briggs, F. M. P. Dehkordy, K. Singha, Frederick Day-Lewis, Judson Harvey, S. R. Chowdhury, John W. Lane
Formation criteria for hyporheic anoxic microzones: Assessing interactions of hydraulics, nutrients and biofilms
Recent experimental studies have detected the presence of anoxic microzones in hyporheic sediments. These microzones are small‐scale anoxic pores, embedded within oxygen‐rich porous media and can act as anaerobic reaction sites producing reduction compounds such as nitrous oxide, a potent greenhouse gas. Microbes are a key control on nutrient transformation in hyporheic sediment, but their associa
Authors
S. R. Chowdhury, J. Zarnetske, M.S. Phanikumar, Martin A. Briggs, Frederick D. Day-Lewis, K. Singha
Geophysical mapping of plume discharge to surface water at a crude oil spill site: Inversion versus machine learning
The interpretation of geophysical survey results to answer hydrologic, engineering, and geologic questions is critical to diverse problems for management of water, energy, and mineral resources. Although geophysical images provide valuable qualitative insight into subsurface architecture and conditions, translating geophysical images into quantitative information (e.g., saturation, concentration,
Authors
Neil Terry, Frederick D. Day-Lewis, John W. Lane, Jared J. Trost, Barbara A. Bekins
Return flows from beaver ponds enhance floodplain-to-river metals exchange in alluvial mountain catchments
River to floodplain hydrologic connectivity is strongly enhanced by beaver- (Castor canadensis) engineered channel water diversions. The hydroecological impacts are wide ranging and generally positive, however, the hydrogeochemical characteristics of beaver-induced flowpaths have not been thoroughly examined. Using a suite of complementary ground- and drone-based heat tracing and remote sensing me
Authors
Martin Briggs, Cheng-Hui Wang, Frederick Day-Lewis, Kenneth H. Williams, Wenming Dong, John Lane
Residence time controls on the fate of nitrogen in flow‐through lakebed sediments
For many glacial lakes with highly permeable sediments, water exchange rates control hydrologic residence times within the sediment‐water interface (SWI) and the removal of reactive compounds such as nitrate, a common pollutant in lakes and groundwater. Here we conducted a series of focused tracer injection experiments in the upper 20 cm of the naturally downwelling SWI in a flow‐through lake on C
Authors
Tyler B. Hampton, Jay P. Zarentske, Martin A. Briggs, Kamini Singha, Judson W. Harvey, Frederick D. Day-Lewis, Farzaneh MahmoodPoor Dehkordy, John W. Lane
Multi-scale preferential flow processes in an urban streambed under variable hydraulic conditions
Spatially preferential flow processes occur at nested scales at the sediment-water interface (SWI), due in part to sediment heterogeneities, which may be enhanced in flashy urban streams with heavy road sand influence. However, several factors, including the flow-rate dependence of preferential hyporheic flow and discrete groundwater discharge zones are commonly overlooked in reach-scale models of
Authors
Farzaneh MahmoodPoor Dehkordy, Martin A. Briggs, Frederick D. Day-Lewis, Kamini Singha, Ashton Krajnovich, Tyler B. Hampton, Jay P. Zarnetske, Courtney R. Scruggs, Amvrossios C. Bagtzoglou
The dual‐domain porosity apparatus: Characterizing dual porosity at the sediment/water interface
The characterization of pore-space connectivity in porous media at the sediment/water interface is critical to understanding contaminant transport and reactive biogeochemical processes in zones of groundwater and surface-water exchange. Previous in situ studies of dual-domain (i.e.,
mobile/less-mobile porosity) studies have been limited to solute tracer injections at scales of meters to 100s
Authors
Courtney R. Scruggs, Martin A. Briggs, Frederick D. Day-Lewis, Dale D. Werkema, John W. Lane
DTSGUI: A python program to process and visualize fiber‐optic distributed temperature sensing data
Fiber‐optic distributed temperature sensing (FO‐DTS) has proven to be a transformative technology for the hydrologic sciences, with application to diverse problems including hyporheic exchange, groundwater/surface‐water interaction, fractured‐rock characterization, and cold regions hydrology. FO‐DTS produces large, complex, and information‐rich datasets. Despite the potential of FO‐DTS, adoption o
Authors
Marian M. Domanski, Daven Quinn, Frederick D. Day-Lewis, Martin A. Briggs, Dale D. Werkema, John W. Lane
Evaluating long-term patterns of decreasing groundwater discharge through a lake-bottom permeable reactive barrier
Identifying and quantifying groundwater exchange is critical when considering contaminant fate and transport at the groundwater/surface-water interface. In this paper, areally distributed temperature and point seepage measurements are used to efficiently assess spatial and temporal groundwater discharge patterns through a glacial-kettle lakebed area containing a zero-valent iron permeable reactive
Authors
Timothy D. McCobb, Martin A. Briggs, Denis R. LeBlanc, Frederick D. Day-Lewis, Carole D. Johnson
Direct observations of hydrologic exchange occurring with less‐mobile porosity and the development of anoxic microzones in sandy lakebed sediments
Quantifying coupled mobile/less‐mobile porosity dynamics is critical to the prediction of biogeochemical storage, release, and transformation processes in the zone where groundwater and surface water exchange. The recent development of fine‐scale geoelectrical monitoring paired with pore‐water sampling in groundwater systems enables direct characterization of hydrologic exchange between more‐ and
Authors
Martin A. Briggs, Frederick D. Day-Lewis, Farzaneh Mahmood Poor Dehkordy, Tyler B. Hampton, Jay P. Zarnetske, Courtney R. Scruggs, Kamini Singha, Judson W. Harvey, John W. Lane