Electronic Theses and Dissertations

Date of Award

1-1-2023

Document Type

Dissertation

Degree Name

Ph.D. in Engineering Science

First Advisor

Robert M. Robert

Second Advisor

Craig J. Hickey

Third Advisor

Robert M. Robert

Relational Format

dissertation/thesis

Abstract

This dissertation presents an exploration of the Self-Potential (SP) and Electrical Resistivity Tomography (ERT) methods applied within the context of the Managed Aquifer Recharge (MAR) project near the Tallahatchie River at Shellmound, MS. The research introduces tools and methodologies, including 80-electrode SP data acquisition systems (80E-SPDAS) and the Hydro-Electrical Aquifer Properties Estimator (HEAPE), to measure SP data in the laboratory and the field. The first segment of the dissertation introduces the Hydro- Electrical Aquifer Properties Estimator (HEAPE), an apparatus designed for high-resolution Self-Potential (SP) data collection. The HEAPE apparatus is utilized in laboratory experiments to measure SP under varying conditions of hydraulic head, temperature, and hydrogeochemistry of water in soil cores. This section also highlights the development of a custom SP data processing program, which is capable of cleaning noisy data and performing regression analyses. Furthermore, this part of the research presents the development of forward modeling of SP and parameter estimation programs. These tools are designed to estimate aquifer parameters from SP data, demonstrating the practical application of the measured data using the apparatus. The second segment of the dissertation introduces the development of the 80E-SPDAS and its application in the laboratory for measuring SP data associated with a pumping test. This section addresses the challenge of noise in SP data, primarily due to the oscillating pressure of the peristaltic pump and ambient electrical influences. To combat this, the Nonlinear Least Squares method, coupled with the Levenberg-Marquardt optimization algorithm, is applied to fit the noisy SP and hydraulic head data. This approach effectively eliminates noise, rendering the data suitable for further analysis and inversion. This segment also delves into the spatial and temporal analysis of SP data, demonstrating the application of SP data in predicting the groundwater flow boundary, determining the extent of the cone of depression, and identifying the locations of drawdown. These analyses show the potential utility of SP data in investigating surface-groundwater interactions for the MAR project. The final segment focuses on characterizing the Mississippi River Valley Alluvial (MRVA) aquifer using ERT and the field application of the developed 80E-SPDAS for collecting SP data to investigate surface-groundwater interactions. The high degree of heterogeneity in the aquifer is revealed, with several zones of higher resistivity anomalies identified as loosely packed sand and gravel zones, preferential groundwater flow pathways, and potential sites for drilling extraction wells. This section also demonstrates the effectiveness of the 80-electrodes SP data acquisition system in real-time monitoring of surface-groundwater interaction, drawdown prediction, and flow direction determination. In conclusion, this dissertation makes contributions to the field of hydrogeology by developing data acquisition systems and applying them in the laboratory and the field. The findings not only enhance our understanding of SP data and aquifer systems but also provide practical solutions for managing groundwater resources effectively, thereby paving the way for future research and applications in this field.

Share

COinS
 
 

To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.