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The belowground architecture of the critical zone (CZ) consists of soil and rock in various stages of weathering and wetness that acts as a medium for biological growth, mediates chemical reactions, and controls partitioning of hydrologic fluxes. Hydrogeophysical imaging provides unique insights into the geometries and properties of earth materials that are present in the CZ and beyond the reach of direct observation beside sparse wellbores. An improved understanding of CZ architecture can be achieved by leveraging the geophysical measurements of the subsurface. Creating categorical models of the CZ is valuable for driving hydrologic models and comparing belowground architectures between different sites to interpret weathering processes. The CZ architecture is revealed through a novel comparison of hillslopes by applying facies classification in the elastic-electric domain driven by surface-based hydrogeophysical measurements. Three pairs of hillslopes grouped according to common geologic substrates — granite, volcanic extrusive, and glacially altered — are classified by five different hydrofacies classes to reveal the relative wetness and weathering states. The hydrofacies classifications are robust to the choice of initial mean values used in the classification and noncontemporaneous timing of geophysical data acquisition. These results will lead to improved interdisciplinary models of CZ processes at various scales and to an increased ability to predict the hydrologic timing and partitioning. Beyond the hillslope scale, this enhanced capability to compare CZ architecture can also be exploited at the catchment scale with implications for improved understanding of the link between rock weathering, hydrochemical fluxes, and landscape morphology.
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Geophysical characterization of karst aquifers using dynamic recharge events
The proposed study aims to deploy seismometers, tiltmeters, and other equipment at the Santa Fe River Sink-Rise system in FL to monitor geophysical responses to recharge events over a two-year period. Geophysical data collected as part of this project will leverage ongoing data collection efforts to enable the interpretation of geophysical responses that arise from hydrologic processes. The overall goal of this remote sensing study is to develop new techniques using data collected at the surface to identify the location of conduits and other subsurface features as well as to provide constraints on flow and hydrologic processes in karst aquifers.
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- Award ID(s):
- 1850667
- PAR ID:
- 10436788
- Publisher / Repository:
- International Federation of Digital Seismograph Networks
- Date Published:
- Format(s):
- Medium: X Size: 5360 MB Other: SEED data
- Size(s):
- 5360 MB
- Sponsoring Org:
- National Science Foundation
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