Impacts of Pleistocene glaciation on large-scale groundwater flow and salinity in the Michigan Basin

Abstract. Most of the current large scale hydrological models do not contain a physically-based groundwater flow component. The main difficulties in large-scale groundwater modeling include the efficient representation of unsaturated zone flow, the characterization of dynamic groundwater-surface water interaction and the numerical stability while preserving complex physical processes and high resolution. To address these problems, we propose a highly-scalable coupled hydrologic and groundwater model (mHM#OGS) based on the integration of two open-source modeling codes: the mesoscale hydrologic Model (mHM) and the finite element simulator OpenGeoSys (OGS). mHM#OGS is coupled using a boundary condition-based coupling scheme that dynamically links the surface and subsurface parts. Nested time stepping allows smaller time steps for typically faster surface runoff routing in mHM and larger time steps for slower subsurface flow in OGS. mHM#OGS features the coupling interface which can transfer the groundwater recharge and river baseflow rate between mHM and OpenGeoSys. Verification of the coupled model was conducted using the time-series of observed streamflow and groundwater levels. Moreover, we force the transient model using groundwater recharge in two scenarios: (1) spatially variable recharge based on the mHM simulations, and (2) spatially homogeneous groundwater recharge. The modeling result in first scenario has a slightly higher correlation with groundwater head time-series, which further validates the plausibility of spatial groundwater recharge distribution calculated by mHM in the mesocale. The statistical analysis of model predictions shows a promising prediction ability of the model. The offline coupling method implemented here can reproduce reasonable groundwater head time series while keep a desired level of detail in the subsurface model structure with little surplus in computational cost. Our exemplary calculations show that the coupled model mHM#OGS can be a valuable tool to assess the effects of variability in land surface heterogeneity, meteorological, topographical forces and geological zonation on the groundwater flow dynamics.

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CUDA-based solver for large-scale groundwater flow simulation

Engineering With Computers ◽

10.1007/s00366-011-0213-2 ◽

2011 ◽

Vol 28 (1) ◽

pp. 13-19 ◽

Cited By ~ 10

Author(s):

Xiaohui Ji ◽

Tangpei Cheng ◽

Qun Wang

Keyword(s):

Groundwater Flow ◽

Large Scale ◽

Flow Simulation

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Multiscale-finite-element-based ensemble Kalman filter for large-scale groundwater flow

Journal of Hydrology ◽

10.1016/j.jhydrol.2012.08.003 ◽

2012 ◽

Vol 468-469 ◽

pp. 22-34 ◽

Cited By ~ 7

Author(s):

Liangsheng Shi ◽

Lingzao Zeng ◽

Dongxiao Zhang ◽

Jinzhong Yang

Keyword(s):

Finite Element ◽

Kalman Filter ◽

Groundwater Flow ◽

Ensemble Kalman Filter ◽

Large Scale ◽

Multiscale Finite Element

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Modelling present and future Po river interactions with alluvial aquifers (Low Po River Plain, Italy)

Journal of Water and Climate Change ◽

10.2166/wcc.2014.058 ◽

2014 ◽

Vol 5 (3) ◽

pp. 457-471 ◽

Cited By ~ 3

Author(s):

M. Mastrocicco ◽

N. Colombani ◽

A. Gargini

Keyword(s):

Groundwater Flow ◽

Large Scale ◽

Flow Model ◽

Transient Flow ◽

Scale Model ◽

Groundwater Flow Model ◽

Po River ◽

Local Conditions ◽

Aquifer System ◽

Hydrological Conditions

A modelling study on a multi-layered confined/unconfined alluvial aquifer system was performed to quantify surface water/groundwater interactions. The calibrated groundwater flow model was used to forecast climate change impacts by implementing the results of a downscaled A1B model ensemble for the Po river valley. The modelled area is located in the north-western portion of the Ferrara Province (Northern Italy), along the eastern bank of the Po river. The modelling procedure started with a large scale steady state model followed by a transient flow model for the central portion of the domain, where a telescopic mesh refinement was applied. The calibration performance of both models was satisfactory, in both drought and flooding conditions. Subsequently, forecasted rainfall, evapotranspiration and Po river stage at 2050, were implemented in the calibrated large scale groundwater flow model and their uncertainties discussed. Three scenarios were run on the large scale model: the first simulating mean hydrological conditions and the other two simulating one standard deviation above and below the mean hydrological conditions. The forecasted variations in groundwater/Po river fluxes are relevant, with a general increase of groundwater levels due to local conditions, although there are large uncertainties in the predicted variables.

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Ice Segregation as an Origin for Lenses of Non-Glacial Ice in “Ice-Cemented” Rock Glaciers

Journal of Glaciology ◽

10.3189/s0022143000011564 ◽

1981 ◽

Vol 27 (97) ◽

pp. 506-510 ◽

Cited By ~ 1

Author(s):

William J. Wayne

Keyword(s):

Groundwater Flow ◽

Large Scale ◽

Water Pressure ◽

Snow Melt ◽

Total Thickness ◽

Rock Glacier ◽

Glacial Ice ◽

Substantial Loss ◽

Rock Glaciers ◽

Ice Segregation

AbstractIn order to flow with the gradients observed (10° to 15°) rock glaciers cannot be simply ice-cemented rock debris, but probably contain masses or lenses of debris-free ice. The nature and origin of the ice in rock glaciers that are in no way connected to ice glaciers has not been adequately explained. Rock glaciers and talus above them are permeable. Water from snow-melt and rain flows through the lower part of the debris on top of the bedrock floor. In the headward part of a rock glacier, where the total thickness is not great, if this groundwater flow is able to maintain water pressure against the base of an aggrading permafrost, segregation of ice lenses should take place. Ice segregation on a large scale would produce lenses of clear ice of sufficient size to permit the streams or lobes of rock debris to flow with gradients comparable to those of glaciers. It would also account for the substantial loss in volume that takes place when a rock glacier stabilizes and collapses.

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A simulation of large-scale groundwater flow on CUDA-enabled GPUs

Proceedings of the 2010 ACM Symposium on Applied Computing - SAC '10 ◽

10.1145/1774088.1774588 ◽

2010 ◽

Cited By ~ 3

Author(s):

Xiaohui Ji ◽

Tangpei Cheng ◽

Qun Wang

Keyword(s):

Groundwater Flow ◽

Large Scale

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Including hydrologic signatures in the calibration of a groundwater-surface water model to improve representation of artificial drain

10.5194/egusphere-egu2020-9283 ◽

2020 ◽

Author(s):

Simon Stisen ◽

Raphael Schneider ◽

Anker Lajer Højberg

Keyword(s):

Surface Water ◽

Groundwater Flow ◽

Large Scale ◽

Agricultural Land ◽

Water Cycle ◽

Regional Scale ◽

Drainage System ◽

Water Model ◽

Hydrological Models ◽

Drain Flow

About half of the Danish agricultural land is artificially drained to make land arable and increase crop yield. Those artificial drains, mostly in the form on tile drains, have a significant effect on the groundwater flow patterns and the whole water cycle. Consequently, the drainage system must also be represented in hydrological models that are used to understand and simulate, for example, recharge patterns, groundwater flow paths, or the transport and retention of nutrients. However, representation of drain in regional- and large-scale hydrological models is challenging due to i) issues with scale, ii) a lack of data on the distribution of the drain network, and iii) a lack of direct observations of drain flow. This calls for more indirect methods to inform such models.We assume that drain flow leaves a signal in certain hydrograph signatures, as it impacts the generation of streamflow. Based on a dataset of observed discharge covering all of Denmark, and simulation results from regional-scale hydrological models, we use machine learning regressors to shed light on possible correlations between hydrograph signatures and artificial drainage. Building up on this step, we run a series of calibration exercises on a hydrological model of the agriculturally dominated Norsminde catchment, Denmark (~100&#160;km2). The model is set up in the DHI MIKE SHE software, as distributed coupled groundwater-surface water models with a grid size of 100&#160;m. The different calibration exercises differed in the objective functions used: either we only use conventional stream flow metrics (KGE), or also include hydrograph signatures that showed sensitive towards drain flow in our regression analysis. We then evaluate the results from the different calibration exercises, in terms of how well the model reproduces directly observed drain flow, and spatial drainage patterns.Despite including hydrologic signatures in the calibration process, the representation of drain flow in large-scale models remains challenging. Eventually, the insight gained from this and similar studies will be incorporated in the National Water Resources Model for Denmark, to help improving national targeted regulation of nitrate application through fertilizers.

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A dual fracture model to simulate large-scale flow through fractured rocks

Canadian Geotechnical Journal ◽

10.1139/t02-068 ◽

2002 ◽

Vol 39 (6) ◽

pp. 1302-1312 ◽

Cited By ~ 7

Author(s):

E Z Wang ◽

Z Q Yue ◽

L G Tham ◽

Y Tsui ◽

H T Wang

Keyword(s):

Groundwater Flow ◽

Large Scale ◽

Fractured Rock ◽

Network Models ◽

Total Porosity ◽

Seepage Flow ◽

Fracture Network ◽

Fracture Model ◽

Rock Masses ◽

Rock Matrix

Discrete fracture network models can be used to study groundwater flow in fractured rock masses. However, one may find that it is not easy to apply such models to practical projects as it is difficult to investigate every fracture and measure its hydraulic parameters. To overcome such difficulties, a dual fracture model is proposed. Taking into account the hydraulic characteristics of the various elements of the fracture system, a hydrogeological medium is assumed to consist of two components: the dominant fracture network and the fractured rock matrix. As the dominant fracture network consists of large fractures and faults, it controls the groundwater flow in rock masses. Depending on the permeabilities of the in-fill materials, these fractures and faults may serve as channels or barriers of the flow. The fractured rock matrix, which includes rock blocks and numerous small fractures, plays a secondary role in groundwater flow in such medium. Although the small fractures and rock blocks possess low permeability, their numbers and their total porosity are relatively large. Therefore, they provide large volume for groundwater storage. In this paper, the application of the proposed model to simulate the groundwater flow for a hydropower station before and after reservoir storage is reported. The implications of the results on the design of the station are also highlighted.Key words: seepage flow, dual fracture model, dominant fracture, fractured rock matrix, case studies, rock-filled dam.

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