Publication Date

Summer 2017

Advisor(s) - Committee Chair

Dr. Jason Polk (Direcotr), Dr. Leslie North, Dr. Patricia Kambesis

Degree Program

Department of Geography and Geology

Degree Type

Master of Science

Abstract

Telogenetic epikarst carbon sourcing and transport processes and the associated hydrogeochemical responses are often complex and dynamic. Among the processes involved in epikarst development is a highly variable storage and flow relationship that is often influenced by the type, rate, and amount of dissolution kinetics involved. Diffusion rates of CO2 in the epikarst zone may drive hydrogeochemical changes that influence carbonate dissolution processes and conduit formation. Most epikarst examinations of these defining factors ignore regional-scale investigations in favor of characterizing more localized processes. This study aims to address that discrepancy through a comparative analysis of two telogenetic epikarst systems under various land uses to delineate regional epikarst behavior characteristics and mechanisms that influence carbon flux and dissolution processes in south-central Kentucky. High-resolution hydrogeochemical and discharge data from multiple data loggers and collected water samples serve to provide a more holistic picture of the processes at work within these epikarst aquifers, which are estimated to contribute significantly to carbonate rock dissolution processes and storage of recharging groundwater reservoirs on the scale of regional aquifer rates. Data indicate that, in agricultural settings, long-term variability is governed by seasonal availability of CO2, while in urban environments extensive impermeable surfaces trap CO2 in the soil, governing increased dissolution and conduit development in a heterogonous sense, which is often observed in eogenetic karst development, as opposed to bedding plane derived hydraulic conductivity usually observed in telogenetic settings. These results suggest unique, site-specific responses, despite regional geologic similarities. Further, the results suggest the necessity for additional comparative analyses between agricultural settings and urban landscapes, as well as a focus on carbon sourcing in urban environments, where increased urban sprawl could influence karst development

Disciplines

Geology | Speleology

Download

Share

COinS