Eric Wade Peterson

Persistence of 17 β-Estradiol in Water and Sediment-Pore Water from Cave Streams in Central Missouri

Concentrations less than 10 ng/L of 17 β-estradiol (E2), a natural estrogen, have been linked to adverse health effects in fish, including skewed sex distributions, reproductive failure, and organ impairment. The persistence of E2 in carbonate aquifer systems is not well documented. Water and sediment from cave streams within the Ozark Plateau of Missouri, USA, were collected and analyzed for E2. The persistence of E2 in the water was examined in two separate experiments, in which the holding temperatures (20°C vs. 4°C), bottle type, exposure to light, and filtration were varied. During two trials, no statistical difference was observed in the concentration of E2, suggesting that E2 is stable within the water. The fate of E2 was also examined in sediment-pore water collected from the cave streams in two independent trials. In trial 1, a significant decrease in E2 was noted over the 29 days of the experiment. However, in trial 2, no change in E2 concentration was observed. The results indicate that E2 is relatively stable in cave stream water and may persist in the sediment.

Identifying water sources in a karst aquifer using thermal signatures

Using thermal data, a unique approach to delineate flow components in a karsts aquifer was conducted. Thermal signatures from seven wells and six springs were analyzed to determine potential relationships among different storage reservoirs and the air temperature. The temperature signatures revealed three distinct reservoirs: epikarst, shallow groundwater, and deep groundwater. The reservoirs have different thermal signatures and relationships with the air temperature. During a wetter period, the epikarst water temperatures more closely follow the air temperature trend and are closer in value, but during drier conditions, the shallow groundwater temperatures are more similar in value to air temperature. Deep groundwater temperatures show no relationship to variations in surface air temperature. Using the water temperatures from the three reservoirs, the sources of water at two major springs, Copperhead and Langle, were delineated. During the wetter period, the shallow groundwater and the epikarst were the primary contributors of water to the springs. As conditions became drier a transition occurred, the deep groundwater became the major source of water to the springs. Variation in temperatures of waters at Copperhead and Langle spring is a result of the epikarst and the shallow groundwater, which represents ineffective thermal reservoirs.

Porosity controls on secondary recovery at the Loudon field, south-central Illinois

AbstractWaterflooding has been used as an effective means to enhance oil recovery in mature oil fields for decades. The success of waterflooding is a function of geology, facies changes, and fluid dynamics, specifically, formation porosity and permeability. Within the Loudon oil field (Illinois), waterflooding has been used to increase production, but the degree of success has been variable. We have used 3D facies modeling was evaluate the variables controlling the success or failure of waterflooding. Three leases within the Loudon field exhibiting varying degrees of waterflood success were investigated. The K. Stubblefield lease, with the highest mean porosity of 13.5%, responded most favorably to waterflooding, with an increase of more than 750  bbl/month. Thick, high-porosity zones are well connected within the lease area, contributing to greater communication among the injection wells and the producing wells. The Rhodes-Williams lease, with porosity of 11.5%, had an increase in production of 350  bbl/...

Longitudinal profile and sediment mobility as geomorphic tools to interpret the history of a fluviokarst stream system

Karst terrains, characterized by closed depressions, subsurface drainage, and caves, account for approximately 10-20% of Earth’s land area (Palmer, 1991; Gillieson, 1996). The degree of karst development varies from region to region as a result of climatic conditions and relief. Consequently, a land surface may exhibit gently rolling soil covered plains with slight depressions or it may include deep depressions, isolated towers, and pointed hills (White, 1988). Dissolution plays a more significant role in the development of karst landscapes than in other landscapes (Jennings, 1985). However, studies have shown that physical erosional processes may also play an important role in the formation of karst systems (Aley, 1965; Sanders, 1981; Palmer, 1991; Bosch & White, 2004; Dogwiler & Wicks, 2004). Regardless of the erosion process, the formation of karst in suitable rock types requires the movement Citation:

Approaching Cave Level Identification with GIS: A Case Study of Carter Caves

Cave passages that are found at similar elevations are grouped together and called levels. The current understanding is that passages within a level are speleogenetically linked to a common static baselevel or stratigraphic control. Cave levels have provided an interpretive framework for deciphering cave development, landscape evolution, and climatic changes. Cosmogenic dating has been successfully used to interpret levels in Mammoth Cave and the Cumberland Plateau; however, this technique is expensive and there are limited funding resources available. Geographic information systems may be used as preliminary procedures to identify cave levels and constrain the timing of level development. A GIS method is applied to the Carter Cave system in northeastern Kentucky. Cave entrance elevations along stream valleys were found by extracting elevation values from a  m digital elevation model. Using a histogram generated from the frequency of cave elevations and a natural breaks classifier, four cave levels were identified in the Carter Cave system. This work improves the understanding of the Carter Cave system evolution and contributes toa methodology that can be used to ascertain an erosion history of karst systems.

Identifying the stream erosion potential of cave levels in Carter Cave State Resort Park, Kentucky, USA

Cave levels, passages found at similar elevations and formed during the same constant stream base level event, reveal information about paleoclimates and karst geomorphology. The investigation presented here examines how Stream Power Index (SPI) relates to cave levels. The study area, Carter Caves State Resort Park (CCSRP), is a fluviokarst system in northeastern Kentucky containing multiple cave levels. SPI determines the erosive power overland flow based on the assumption that flow accumulation and slope are proportional to potential for sediment entrainment. Part of this digital terrain analysis requires the creation of a flow accumulation raster from a digital elevation model (DEM). In creating the flow accumulation raster, one has the option to fill depressions (also considered errors) within the DEM. Filling these depressions, or “sinks,” creates a well-connected stream network; however it also removes possible sinkholes from the DEM. This paper also investigates the effects a filled and an unfilled DEM have on SPI and what each reveals about erosion potential in the area. The data shows that low elevations within the filled DEM maintain a high SPI value when compared to the unfilled DEM. The filled DEM also created a stream network similar to reality. The unfilled DEM demonstrated similar SPI results between all levels, indicating a well-connected karst system. In order to truly understand the mechanics of this system, a combination of these two DEMs is required.

Optimizing DEM resolution inputs and number of stream gauges in GIS predictions of flood inundation

Spatial analysis using Geographic Information Systems (GIS) is evaluated for its ability to predict the potential hazard of a flood event in the Illinois River region in the state of Illinois, USA. The data employed in the analysis are available to the public from trusted organizations such as Illinois State Geological Survey and the US Geological Survey (USGS). Since available GIS data may be limited for flood risk modeling in some parts of the world, the purposes of this study are to examine the use of spatial analysis in a GIS to determine flood inundation risk and to produce an accurate flood inundation vulnerability map employing the least amount of data. This study concentrates on areas that have stream gauge data with definable flood stage(s) and utilizes the inverse distance weighted (IDW) interpolation method on different digital elevation models (DEM) with different spatial resolutions (1 m, 10 m, and 30 m) to determine the extent of flooding over the study area. Resulting maps created for the Illinois River region yielded about 80% agreement to the effects of an actual flood event on the Illinois River near Peoria, IL on April 23, 2013. A four-gauge distribution scenario using a 10 m DEM produced the most accurate results, but all scenarios generated reasonable flood simulation. Thus, we speculate that it is possible to create a flood prediction map with a reasonable amount of accuracy using only two initial input data layers: stream gauges and a DEM.

Surficial geology of the Woodstock, IL 7.5 minute Quadrangle, Mchenry County, Illinois, scale 1:24,000

ABSTRACT The surficial geology of the Woodstock 7.5-minute Quadrangle, which is located in the northwest part of the Chicago-Metropolitan Area, was mapped to better address natural resource issues and better understand local geologic history. In the study area, the population is dependent completely upon groundwater for water supplies, and groundwater withdrawals are expected to increase dramatically in coming decades. The landscape and surficial geologic materials in the Woodstock Quadrangle are a result of numerous glaciations during the Quaternary. Surficial sand and gravel deposits, along with buried outwash deposits from older glacial events, constitute important aquifer and aggregate resources for local residents and industry. The landscape within the Woodstock Quadrangle includes glacial moraines, ice-walled lake plains, kettles, incised valleys, and glacial lacustrine deposits. These landforms, coupled with the thick glacial sediments, record a complicated geologic history associated with glacial processes and paleoclimate change. The surficial geologic map of the Woodstock Quadrangle consists of seven lithostratigraphic units associated with the most recent Wisconsinan glaciations in North America. These geologic units include multiple till deposits, outwash sediments, lacustrine sediments, and modern alluvium and peat deposits. This map provides the base geologic knowledge for planners, decision-makers, and other scientists.