Use this URL to cite or link to this record in EThOS: https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.738133
Title: Using Ground Penetrating Radar (GPR) for identifying floodplain and riverbed structural heterogeneity and implications for groundwater-surface water exchange
Author: Dara, Rebwar Nasir
ISNI:       0000 0004 7226 9842
Awarding Body: University of Birmingham
Current Institution: University of Birmingham
Date of Award: 2018
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Abstract:
The aim of the study is to investigate the variability in riverbed permeability fields in an unprecedented spatial resolution and quantify the impacts on controlling hyporheic exchange fluxes. Geophysical surveys were conducted deploying GPR on the floodplain and within the channel. At locations identified to be representative for the range of streambed hydrofacies in investigated stream reach, multi-level mini-piezometer networks were installed in the streambed. The results of GPR surveys in both sites provided different radar reflections which indicated a range of different radar facies and helped to delineate the type and extend of high and low conductive materials. The localised high Darcy fluxes inside high conductivity piezometers indicated rapid discharge of groundwater due to the enhanced connectivity to deeper groundwater. Whereas, low flow velocity within and around low conductivity peat and clay lenses indicated that these layers substantially inhibit groundwater upwelling, resulting in enhanced streambed residence and reaction times. The increase in residence time and the related depletion in the volume of DO facilitated the development of conditions necessary for nitrate reduction. In contrast, preferential flow paths and short residence times in highly conductive drift deposits resulted in no significant changes in nitrate concentrations along hyporheic flow paths.
Supervisor: Not available Sponsor: Higher Committee for Education Development in Iraq (HCED)
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.738133  DOI: Not available
Keywords: GE Environmental Sciences
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