UNCOVERING THE SPELEOGENESIS OF THE CARTER CAVE SYSTEM IN CARTER COUNTY, KENTUCKY. Brianne S. Jacoby. 76 Pages May 2011

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1 UNCOVERING THE SPELEOGENESIS OF THE CARTER CAVE SYSTEM IN CARTER COUNTY, KENTUCKY Brianne S. Jacoby 76 Pages May 2011 This study outlines the evolution of the karst system at Carter Caves State Resort Park, Carter County Kentucky using Geographic Information Systems (GIS). APPROVED: Date Eric W. Peterson, Chair Date John C. Kostelnick Date Toby Dogwiler

2 UNCOVERING THE SPELEOGENESIS OF THE CARTER CAVE SYSTEM IN CARTER COUNTY, KENTUCKY Brianne S. Jacoby 76 Pages May 2011 Cave passages that are found at similar elevations are grouped together and called levels. Current understanding is that passages within a level are speleogenetically linked to a common static base level or stratigraphic control. Cave levels are important aids in 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 (GIS) may be used as a preliminary procedure to identify cave levels and constrain the timing of level development. This method has been applied to the Carter Cave system in northeastern Kentucky. The Carter Cave system is within the karst landscape found along the western edge of the Appalachians and contains multiple daylighted caves at various elevations along valley walls. These characteristics make the Carter Cave system an ideal location

3 to apply GIS to cave level identification and evolution. Cave openings along stream valleys were found by extracting elevation values from a 10 x 10 meter digital elevation model (DEM). Using a histogram generated from the frequency of cave elevations and a natural breaks classifier, the number and elevation of cave levels were determined. An argument can be made for either four or five cave levels in the Carter Cave system; however, other studies have identified four levels in both Mammoth Cave and the Cumberland Plateau. Further analysis suggests the possible fifth level formed as a result of a change in lithology rather than an event that influenced the local base level. The GIS was also used to calculate the volume of material lost within each level. Level thickness lost and published denudation rates were used to calculate the relative time required to form each level. There was not one denudation rate applicable to all levels within the cave system, but the rates varied between 12 m/ma and 40 m/ma. Results indicate that the cave system took to between 3.4 and 5.7 Ma to form. This work improves the understanding of the Carter Cave system evolution and contributes a methodology that can be used to ascertain an erosion history of karst systems. APPROVED: Date Eric W. Peterson, Chair Date John C. Kostelnick Date Toby Dogwiler

4 UNCOVERING THE SPELEOGENESIS OF THE CARTER CAVE SYSTEM IN CARTER COUNTY, KENTUCKY BRIANNE S. JACOBY A Thesis Submitted in Partial Fulfillment of the Requirements for the Degree of MASTER OF SCIENCE Department of Geography-Geology ILLINOIS STATE UNIVERSITY 2011

5 UNCOVERING THE SPELEOGENESIS OF THE CARTER CAVE SYSTEM IN CARTER COUNTY, KENTUCKY BRIANNE S. JACOBY APPROVED: Date Eric W. Peterson, Chair Date John C. Kostelnick Date Toby Dogwiler

6 AKNOWLEDGEMENTS I would first like to thank my thesis advisor and committee chair, Dr. Eric Peterson. The finished product would not have been possible without his continuous guidance, encouragement, and constructive criticism. Thank you to my other committee members, Dr. John Kostelnick for his patience and guidance through the GIS applications within this project and Dr. Toby Dogwiler for his valuable feedback and enthusiasm. I want to extend another thank you to the faculty and staff of the Department of Geography-Geology for their support and overall confidence in my abilities. Thank you to my field assistants, Simone Runyon and Jonathan Love who both kept a great attitude and helped me cover much ground even though the working conditions were beyond optimal. Additionally, thank you to my colleagues; these past two years have been challenging and overwhelming at times, but your support has made this experience memorable but more importantly, a blast. Finally- Dad, thank you for your encouragement and enthusiasm. You have always been excited about the projects I undertake, regardless of how different they are. Mom, thank you for always listening and for helping me work through problems without giving me the answer; these past few years have shown me the value of that gift. Kirsten, thank you for your continuous support and keeping my perspective on track. Lastly, thank you Grandma for sharing your love of learning with me; your determination and achievements in higher education has shown me what is possible. B.S.J. i

7 CONTENTS Page AKNOWLEDGEMENTS CONTENTS TABLES FIGURES i ii iii iv CHAPTER I. INTRODUCTION 1 II. APPROACHING CAVE LEVEL IDENTIFICATION WITH GIS 9 ABSTRACT 10 INTRODUCTION 11 METHODS 18 RESULTS AND DISCUSSION 20 CONCLUSIONS 32 ACKNOWLEDGEMENTS 33 REFRENCES 34 III. CALCULATING CAVE LEVEL DEVELOPMENT TIME WITH GIS 37 ABSTRACT 38 INTRODUCTION AND BACKGROUND 39 METHODS 45 RESULTS 51 DISCUSSION 55 CONCLUSIONS AND FUTURE WORK 59 ACKNOWLEDGEMENTS 60 REFRENCES 61 IV. SUMMARY OF CONCLUSIONS 65 REFERENCES 70 ii

8 TABLES Table Page 1. Comparison between 30-meter DEM and 10-meter DEM results Distributions of caves and cave elevation in relation to their corresponding level Distribution of distance between caves and streams in relation to their corresponding level Level Summary Data for Options 1 and The extent of level formation at Mammoth Cave and the Cumberland Plateau Table displaying chosen denudation rates and their corresponding geographic location The timing of level development based rates chosen (Table 4). 53 iii

9 FIGURES Figure Page 1. Location of Carter Caves State Resort Park (CCSRP) Histogram displaying cave elevation frequency in CCSRP Levels associated with Option 1, consisting of four levels Levels associated with Option 2, consisting of five levels Relationship between cave entrance and exit elevations and their associated level Relationship between levels and the distance between cave and streams Location of Carter Caves State Resort Park (CCSRP) Visual depiction of how the 3D Analysis tool is used to calculate the level volume and area as represented for the study area Relationship between the number of cave opening per level (Table 4) and the estimated level development time as calculated in Table Flow chart depicting datasets, processes, and outputs used in this thesis. 67 iv

10 CHAPTER I INTRODUCTION 1

11 Karst describes terrain that contains unique surficial landforms such as sinkholes and cave entrances, and subterranean landforms such as caverns, passageways, and the highly porous upper zone of soluble bedrock known as epikarst. These structures form through the dissolution of evaporites and calcium-bearing rocks like limestone. The amount and rate of dissolution depends greatly on climate in addition to the properties of the water moving through the system, the current base level, and the existing structure of the rock, such as fractures and bedding planes, available to groundwater flow (Palmer, 1987). Examining the evolution of karst systems gives greater insight to the system s complicated mechanics and is important to understanding paleoenvironments in the context of past base levels. Contributing water properties that control dissolution include the concentration of carbon dioxide in the water, the quantity of discharge flowing through the system, the kinetics of reactions, water temperature, the saturation of the water with respect to calcium, and what occurs when different water chemistries combine underground (Bögli, 1964; Dreybrodt, 1981; Kaufmann, 2009; Palmer, 1991). Dreybrodt and Gabrovsek (2003) point out that dissolution begins with a crack or fracture in the rock and that continued dissolution is due to the amount of carbon dioxide (CO 2 ) within the water. This CO 2 likely comes from the atmosphere, which joins with water as it infiltrates through the soil. Once limestone (CaCO 3 ) is exposed to water (H 2 O) and CO 2, it is dissolved and converted to the calcium (Ca 2+ ) and bicarbonate (HCO - 3 ) ions. CaCO 3 + H 2 O + CO 2 Ca 2 + 2HCO 3 - (1) Equation (1) shows that the dissolution of CaCO 3 is influenced strongly by chemical processes (Bögli, 1964). For each CO 3 - molecule that is detached from calcite, there has 2

12 to be one molecule of CO 2 to react with HCO - 3 allowing dissolution to occur (Dreybrodt and Gabrovsek, 2003). Water enriched with CO 2 dissolves the calcite and removes it through the aqueous solution. Dissolution produces a system where waterways are developed in both vertical and horizontal directions. Flow direction is dependent on passage width, diameter, and orientation; the development of the system depends on the elevation of base flow, stratigraphy, the deflection of vadose water to lower levels, discharge variations, and variations in chemistry within the system (Palmer, 1987). Passages can develop when located over an impermeable rock surface that sits above surface rivers, or when vadose flow is diverted in another direction due to bedding plane variations within a unit. Rapid discharge or an extended exposure to discharge causes passage growth. Long periods of static base level with active dissolution allows for large passages to develop. When river incision rates increase as a result of the regional base level lowering, groundwater flow is diverted to lower elevations (Anthony and Granger, 2004). When flow diversion occurs, passages become abandoned by groundwater flow and their growth rate is reduced or stopped. Finally, development is also dependant on the chemistry differences between the bedrock and the water moving through the system. These factors contribute to the development of cave passages. Comparing the elevations of wide, large passages to narrow passages can give insight to events of static flow versus rapid incision. Passages that are created by static flow and correlate with other passages at similar elevations are grouped together and considered a layer or level (Palmer, 1987). These cave levels are understood to be a significant landforms left in the rock record that can help in deciphering the timing of cave system development. Understanding the 3

13 timing of cave system development provides insight into when there were periods of stable base flow and when the base level decreased. Passages and individual levels form by active solution at a stable base level. Furthermore, multilevel caves form by episodic lowering of the local base level in response to regional discharge changes. Deciphering where a level is located is determined by a piezometric limit (Palmer, 1987), the location where vertical flow that was influenced by gravity, changes to horizontal flow that is now influenced by hydrostatic flow. This is often seen in an area where a canyon turns into a tube feature. Levels reflect when there were periods of static base level. Knowing when stagnant flow occurred can provide information about what was occurring climatically while the levels were forming. For example, static base level can be the result of glacier forming activity. When this occurs, the flow of water globally is limited because water is being stored within the glacier. Uplift is another cause of low flow conditions. Understanding the duration of level development explains how long upstream events occurred. This information can combine with other area studies to develop an understanding of paleoclimate and demonstrate how upstream events affect regions downstream. Engel and Engel (2009) suggest that by understanding timing, it is possible to start interpreting a region s paleoclimate and hydrologic systems. Approximately 55 percent of Kentucky is underlain by karstic limestone (Florea et al., 2002). Perhaps the best-known karst feature in Kentucky is Mammoth Cave, located near central Kentucky. At Mammoth Cave, there has been a great amount of research surrounding the development of this system including sediment dating. Through dating the cave sediment, geologists are able to develop a more definite history of a cave 4

14 system (White, 2007). When periods of static base level change to periods of rapid incision, cave sediments accumulate in abandoned cave passageways. This transition and accumulation can be the result of flow changes as described previously. Knowing when sediment was deposited provides insight into the paleoclimate. Granger et al. (2001) developed a precise evolution of the Mammoth Cave system relating to the incision of the Green River using cosmogenic dating of 26 Al and 10 Be isotopes in cave sediments. Their results showed that incision occurred during the Pliocene-Pleistocene in response to various glacial events and the area has maintained erosion rates of 2-7 meters per million years (m/my) for the past 3.5 my, despite increased river incision rates of 30 m/my during the Pleistocene. Granger et al. (2001) identified seven events which alternated between static base level and valley incision that affected the development of the cave system. Their study concluded that there are a minimum of four levels within Mammoth Cave National Park. They had weaker evidence that suggested a fifth level existed within the park. Another heavily karstified area in Kentucky is the Cumberland Plateau. This area is located directly west of the Valley and Ridge Providence of the Appalachian Mountains, which run along the southeastern border of the state. According to Anthony and Granger (2004) this region has experienced about 180 million years of differential lowering between the sandstone units at the top of the plateau and the underlying limestone units. This lowering is linked to changes in the water table elevation. Anthony and Granger (2004) dated cave sediments through cosmogenic dating of 26 Al and 10 Be isotopes and found the clastic sediments in the area correlated well with known past deposition, uplift, and incision events in the area. The cave levels and associated 5

15 development time identified through their research correlated to incision by the Green River and Cumberland River. In addition, the cave levels were developed at times similar to those of the Mammoth Cave area. They also found that the area had a similar lithology and climate history to the Mammoth Cave system. Both systems are located within the unglaciated Ohio River Basin and the history of cave development went into the Pleistocene. In a review of Granger et al. (2001) and Anthony and Granger (2004), White (2007) stated that the timing of cave development described in both the Mammoth Cave and Cumberland Plateau studies applies to all karst development in south-central Kentucky. He went further to suggest that the findings can be applied to the paleoclimate of the eastern United States. Although sediment dating has proven to be successful in assembling detailed paleoclimate records worldwide, it is also a very costly procedure. In addition, results are more reliable when sediment is found in caves that are undisturbed. The Carter Caves system in northeastern Kentucky is a very well developed karst system. The geology of the area is similar to that of Mammoth Cave and the Cumberland Plateau in lithology and climatic history as well as also being south of the Pliocene-Pleistocene glacier maximum. However a number of caves located in Carter Caves State and Resort Park (CCSRP) are opened to the public. Before there is a push for sediment dating of this system, a sampling plan is needed to optimize sediment collection. If applicable, the GIS approach provides spatial information for use in developing a sampling plan that identifies locations that will optimize the collection of sediment data used in dating analysis. Denudation describes the act of lowering the land surface through erosion. Denudation rates for limestone have been discussed in the literature since at least the 6

16 1960s. A universal rate has yet to be established for limestone, although this is not surprising since the rate of erosion depends largely on the climate, soil composition, and precipitation (White, 2009). The use of one denudation rate for all limestone introduces a significant amount of assumptions such as suspecting that all limestone dissolves the same regardless of composition, geographic location, exposure to the atmosphere, or surrounding soil composition. That being said, a rate of 30 m ma -1 seems to represent soil covered, temperate karst regions like the Appalachian area well (White, 2009). This rate was determined from measurements and estimates of karst denudation rates in carbonate bedrock and surface stream downcutting rates. CCSRP has been studied by research groups from universities including Wittenberg University (WU), Winona State University (WSU), and Illinois State University (ISU). Woodside (2008) surveyed and analyzed surface features to determine if they were true surface features or collapsed caves. This is important when connecting cave level elevations because it helps avoid the identification of false levels. WSU and WU have assembled information regarding the geographic location of cave entrances and exits along with most of their elevations. Harlan (2009) and Peterson et al. (in review) performed the preliminary work on identifying the cave levels of Carter Caves. The goals of this study are to refine the understanding of cave levels within CCSRP and to determine the time associated with the development of each level and the system as a whole. Calculating the development time provides a better understanding of the evolution of the park. The calculated times will be analyzed to determine if they correlate to the speleogenesis of Mammoth Cave and the Ohio River Valley. Correlation between the systems would provide insight to the role of base level changes and 7

17 paleoenvironments on karst development as well as provide more insight into the complicated karst hydrogeology. I hypothesize that the number of cave entrances within each level correlates with the duration of time required in developing that level; that is longer periods of static flow will result in more cave development. I am using the number of cave entrances and exits as a proxy to passage size. I chose the number of caves to be directly related to the duration of cave development because longer exposure to water results in more dissolution and thus creates larger passages. As the river incises through the limestone, more cave entrances will be exposed. I also hypothesize that the formation of the Carter Cave system was influenced by the same events that shaped the Mammoth Cave area and are linked to the incision of the Ohio River Valley. This study will additionally verify Harlan s (2009) findings related to the distance of cave openings away from streams. The oldest levels are at the highest elevations and therefore I expect cave entrances and exits associated with the oldest level to be the furthest away from streams. The research questions will be addressed as follows. Chapter II will discuss how the number of cave levels are determined and the relationship between cave openings and streams. Level age will be compared to the distance between streams and caves to see if caves that are the furthest away from streams correlate to the oldest level. Chapter III will focus on the comparison between the number of caves in each level and the chosen extent of level development to see if a large number of caves correlate to a long duration of cave development. The timing of level development will be compared to Mammoth Cave, Cumberland Plateau, and the Ohio River events to see if they correlate. Chapter IV will present a final summary of results and conclusions. 8

18 CHAPTER II APPROACHING CAVE LEVEL IDENTIFICATION WITH GIS 9

19 ABSTRACT Cave passages that are found at similar elevations are grouped together and called levels. Current understanding is that passages within a level are speleogenetically linked to a common static base level 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 (GIS) may be used as a preliminary procedure to identify cave levels and constrain the timing of level development. This paper is an example of that GIS application in the Carter Cave system in northeastern Kentucky. Cave entrance elevations along stream valleys were found by extracting elevation values from a 10 x 10 meter digital elevation model (DEM). Using a histogram generated from the frequency of cave elevations and a natural breaks classifier, the number and elevation of cave levels were determined. An argument can be made for either four or five cave levels in the Carter Cave system; however, other studies have identified four levels in both Mammoth Cave and the Cumberland Plateau. This work improves the understanding of the Carter Cave system evolution and contributes a methodology that can be used to ascertain an erosion history of karst systems. 10

20 INTRODUCTION In fluviokarst, dissolution creates a system vertically and horizontally connecting surface and subsurface flowpaths. Passage development is dependent on the elevation of base flow, stratigraphy, the diversion of water in the unsaturated zone to lower levels, discharge variations, and variations in chemistry (Palmer, 1987). Long periods of static base level with active dissolution allow for large passages to develop in discrete levels, graded to the regional hydrologic network. When river incision occurs as a result of regional base level lowering, groundwater flow is diverted to lower elevations (Anthony and Granger, 2004). Subsequently, dissolution and passage enlargement is limited or stopped in the abandoned upper levels as karst development becomes focused at the new base level. Alternating sequences of base level incision and aggradation results in a complex overprinting of level development with transitional passage morphologies and deposition or removal of broadly distributed sediment packages (Granger et al., 2001). Deciphering the history of speleogenesis in such systems, including the delineation of cave levels, provides insight to the history of past base level changes and the associated glacio-eustatic or tectonic processes. Passages that are created by static base level and correlate with other passages at similar elevations are grouped together and considered a layer or level. These cave levels are understood to be significant landforms left in the rock record that can help to decipher the timing of cave system development (e.g. Anthony and Granger, 2004; Granger et al., 2001). As described above, multilevel caves form by episodic lowering of the local base level in response to regional discharge changes. Deciphering where the 11

21 flow has changed from predominantly horizontal flow to vertical flow is considered to define the cave level boundary (Palmer, 1987). About 55% of Kentucky is underlain by karstifiable limestone (Florea et al., 2002). The Carter Cave system in northeastern Kentucky is a very well-developed karst system (Figure 1). Located roughly 290 kilometers east-northeast of the Mammoth Cave system, the Carter Caves system is located primarily within Carter Cave State Resort Park (CCSRP). The park is located in Carter County, in which approximately a quarter of the area is associated with karst landform development (Engel and Engel, 2009). CCSRP consists of approximately 106 square kilometers of deeply incised valleys, characteristic of the Cumberland Plateau. The local base level is Tygarts Creek. Within CCSRP Cave Branch and Horn Hollow streams are the main surface tributaries. Horn Hollow drains to Cave Branch and the flow in both streams is perennial. In many reaches the surface stream flow is diverted through the subsurface (e.g., Horn Hollow Cave, Bat Cave, and Annex Cave). Downstream of the resurgence from Annex Cave, flow from Horn Hollow joins Cave Branch via a spring at the downstream end of H2O Cave and then eventually flows into Tygarts Creek near the southern boundary of the park. After receiving the waters from Cave Branch, Tygarts Creek flows north into the Ohio River. 12

22 Figure 1. Location of Carter Caves State Resort Park (CCSRP). 13

23 Horn Hollow Valley is intensely karstified and primarily drained by subsurface flow (McGrain, 1966). While a surface stream channel is present within the valley, upstream of Bowel Spring the surface flow is ephemeral and only observed during high precipitation events when subsurface flowpaths become inundated and overflow. Engel and Engel (2009) provide a detailed description of the stratigraphy and topography of CCSRP. The bedrock formations within CCSRP are similar to those at Mammoth Cave although the unit thicknesses are thinner in the CCSRP area. Mississippian in age, the Borden Formation is the oldest bedrock in the park. This unit is approximately 90 meters thick and consists largely of fine-grained sandstone and siltstone with alternating layers of shale and constrains the tributary down cutting in the area (Ochsenbein, 1974). The Newman Formation is next in the sequence and contains the caves for which the area is known. This unit is Mississippian in age and is made up of the St. Louis Limestone, the St. Genevieve Limestone, and the Upper Member of the Newman Formation. The St. Louis Limestone is approximately 20 meters thick and is argillaceous, with some dolomitic and silicified layers. The St. Genevieve Limestone is approximately 30 meters thick and consists of very light olive-gray to olive-gray oolitic and skeletal limestones with some intercalated shale and sandstone. The limestones are thin to thickly-bedded with occasional cross-bedding. The Upper Member of the Newman Formation is approximately 10 meters thick and contains a variety of units that are difficult to differentiate. Thick sequences of medium to coarse-grained, red and gray chert siltstone and are typically found with cross-bedding. The Upper Member also contains beds of brecciated limestone and shale. Other portions of the formation are calcarenite to micritic, oolitic limestone with occasional brachiopods and gastropods 14

24 fossils. Joints are prominent in the Upper Member of the Newman Formation and St. Genevieve limestones, providing recharge sites for aggressive waters that drive dissolution of the carbonate rock (Engel and Engel, 2009; McGrain, 1966). The Carter Caves Sandstone caps portions of the actively forming cave system and is a part of the Pennsylvanian-aged Pennington Formation, the youngest formation in the park. This unit is a fining-upwards sequence of white to tan, fine to medium-grained, well-sorted quartz sandstone. It weathers to a honeycomb appearance. The Pennington Formation also includes the Lee Sandstone. The Lee Sandstone is a strong, fine to medium-grained quartz sandstone and overlies the Upper Member of the Newman Formation or the Carter Caves Sandstone, varying by location in the park. The entire Pennington Formation is over 100 meters thick. Prior to the onset of the Pleistocene glaciations, landscape denudation and evolution was occurring at a relatively slow rate and base level was much more static than it has been since the onset of glaciation (Granger et al., 2001). It is widely assumed that this period of stability provided sufficient means to develop some of the very large upper-level trunk conduits found in Mammoth Cave (Granger et al., 2001), the Cumberland Plateau (Anthony and Granger, 2004), and in CCSRP (Engel and Engel, 2009; Peterson et al., in review). Subsequent to the onset of glaciation, the region has been strongly influenced by Pleistocene glaciations. Prior to glaciation, northeastern Kentucky was part of the headwaters branch of the Teays River which flowed from North Carolina north through the CCSRP region and on toward west-central Ohio (Janssen, 1953; Ver Steeg, 1946). Although the area lies south of the Pleistocene glacial maximum, north-flowing rivers 15

25 were frequently dammed and diverted by ice sheets (Granger et al., 2001; Rhodehamel and Carlston, 1963). During periods of stream impoundment, sediments are likely to have accumulated in the valleys. Engel and Engel (2009) have proposed that the sediments in upper-level caves at CCSRP (e.g., Saltpetre Cave) are preserved remnants of these deposits. As the Ohio River drainage reorganized during the later portion of the Pleistocene it captured much of the southerly portion of the old Teays drainage in eastern Kentucky and West Virginia (Andrews, 2006; Rhodehamel and Carlston, 1963; Teller, 1973; Ver Steeg, 1946). During periods when the glacially-impounded valleys drained or when the Ohio River incised, base level changes occurred. Any period of sustained and stable base level can potentially result in karst development graded along or just below the water table (White, 1988). Granger et al. (2001) and Anthony and Granger (2004) have demonstrated that these base level changes have been recorded in a consistent manner in widely separated cave systems. CCSRP has over 130 documented caves and over 18 kilometers of mapped passageways. There are both phreatic and vadose caves within CCSRP (Peterson et al., in review). In relatively flat-lying rocks, like those in CCSRP, phreatic caves form primarily along bedding planes. Vadose passages form along vertical structures, such as bedrock joints. Although cave formation has occurred in all limestone units at the park, the St. Genevieve is the major cave producing unit. While published data on the karst of CCSRP is limited, a number of researchers have investigated the area. Geographic locations of cave entrances have been assembled in an unpublished database by the Wittenberg University Speleogical Society. Dogwiler and Wicks (2004) assessed the sediment entrainment dynamics and frequency within the 16

26 Cave Branch and Horn Hollow karst systems. Woodside (2008) surveyed and analyzed the surface features to determine if they formed as a result of surface processes or cave collapse. His research provided insight into the speleogenesis of Horn Hollow Valley and provides data concerning the connectivity of caves. Harlan (2009) and Peterson et al. (in review) performed initial work by identifying the cave levels of Carter Caves. Through a GIS analyses based on a 30-meter digital elevation model (DEM), those authors proposed a preliminary delineation of four different cave levels in the park. The goal of this study is to refine the model of cave level delineation proposed by Harlan (2009) and Peterson et al. (in review). I propose to refine their understanding of the cave levels within CCSRP by using a DEM with a higher spatial resolution to better determine the number of levels present and how the levels relate to existing streams. Deng et al. (2008) discuss the relationship between terrain analysis and scale across landscapes and concluded that resolution affects point-specific and topographic attributes. I expect that by utilizing a DEM with a finer spatial resolution, more accurate elevation and distance measurements will be found. The results of this work will be useful to determine the thickness of levels and for calculating an estimated time required for their development. Constraining the timing of level development provides a better understanding of the speleogenesis of CCSRP and provides an opportunity to compare its development to the speleogenesis of Mammoth Cave and the reorganization of the Ohio River Valley. Correlation between these systems extends the understanding of the relationship between base level changes and paleoclimate into the former Teays River valley of northeastern Kentucky and West Virginia. 17

27 METHODS A Geographic Information System (GIS) was used to find and visualize the location of levels within CCSRP. Cave opening data, compiled from GPS measurements and topographic maps, were provided by the Wittenberg University Speleological Society (Horton Hobbs, personal communication). A 1/3 arc second (approximately 10 meters) DEM, from the U.S. Geological Surveys Seamless website ( was used to find cave elevations and determine the stream network in the region. Typical horizontal accuracy associated with these DEMs according to the National Standard for Spatial Data Accuracy (NSSDA) is approximately ± meters and the vertical accuracy is approximately ± meters (Blak, 2007). The steps taken to perform this task are as follows. First, the DEM and cave entrance and exit locations were converted from a geographic coordinate system to the Universal Transverse Mercator (UTM) zone 17 north, projected coordinate system. There were cave openings within the database that were outside of the DEM s extent and these were eliminated. In addition, redundant caves within the database were identified by comparing their latitude, longitude, and elevation values and then removed to eliminate bias from the attribute table. The DEM and cave opening datasets were used in the GIS to locate the cave level elevations by extracting elevation values from the DEM for each cave point. Next, a histogram was created displaying the frequency of cave entrances and exits at each elevation. The divisions among the levels were identified from both visual inspection of the histogram and by utilizing the natural breaks statistical classifier within ArcGIS. The elevation range for a level was set to the high and low values for the respective natural breaks 18

28 In order to confirm the range of level elevations, field work was performed to determine the limestone/sandstone contact. The contact was found at approximately 274 meters. Comparing this elevation to that of cave elevations determined from the DEM indicated that some cave entrances were located within the sandstone unit. Although cave entrances are generally found within limestone, there were cases where sandstone was located directly above the entrances, making it appear as if some caves were in sandstone. These caves were kept in the dataset, but are understood to be associated with the uppermost cave level (see shaded area in Figure 2). In order to determine the straight-line horizontal distance (Euclidean distance) between cave entrances and the adjacent surface stream path, an artificial stream network was derived using the hydrology tools in the GIS. A vector stream network layer at a scale of 1:24,000 was available from the Kentucky Geological Society, but it did not provide enough detail for this study. When creating the stream network a threshold of accumulation, or total number of cells that flow into a given area, has to be determined. During field work, the head of streams were marked with a GPS unit and later viewed in the GIS. Various threshold values were experimented within the GIS and a value of 70 cells was chosen as the one that best matched the stream network observed in the field. Next, the DEM and stream file were reprojected to an equidistant conic projection with standard parallels within the park boundary to limit distance distortion. Euclidean (straight-line) distance between cave entrances and streams was then calculated and output in the form of a raster grid with each cell at the location of a cave containing the distance in meters to the nearest stream segment. 19

29 RESULTS AND DISCUSSION In Peterson et al. s (in review) investigation of the levels at CCSRP, they conducted an error analysis comparing 43 field-measured elevations for karst features, derived from a Kestrel electronic altimeter and an analog altimeter, to elevations derived from a 30-meter DEM. Elevations from the 30-meter DEM were slightly higher in elevation than the field-measured elevations, with a mean error of meters and a 95% CI of 1.25 meters. Based on the associated error, they concluded that using DEMs provided an efficient way of obtaining elevation values for cave openings. This project took their results a step further by performing the same methods with a 10-meter DEM. Using the 10-meter DEM, the accuracy of modeled elevations were improved, decreasing the mean error to meters with a 95% CI of 1.03 meters. While statistically there is no difference in the mean error obtained from using the 30-meter DEM as compared to those obtained using the 10-meter DEM [t(84) = 0.75, p = 0.46], the lower error associated with the 10-meter DEM suggests that the use of the higher resolution DEM is a relative improvement over the 30-meter DEM. The elevation of the cave openings are not normally distributed (Figure 2). A higher frequency of openings exists between the elevations of 230 and 260 meters. Furthermore there are clear groupings of the data, some of which show a normal distribution within themselves. These groups are divided by natural breaks at the following elevations: 228 meters, 240 meters, and 253 meters. There is arguably a fourth break at 263 meters. For this reason, the number of levels is referred to from this point forward as Option 1, which consists of four levels, and Option 2, which consists of five levels. The cave levels within Option 1 and Option 2 are the same except that 20

30 Option 1, Level 4 is split into two levels for Option 2: Level 4 and Level 5 (Figure 3 and Figure 4). Figure 2. Histogram displaying cave elevation frequency in CCSRP. Option 1 consists of four levels and are labeled in bold text. Option 2 consists of 5 levels, where Option 1, Level 4 is split into two levels. The shaded area represents caves with elevations above the limestone/sandstone contact. 21

31 Figure 3. Levels associated with Option 1, consisting of four levels. Level 4 is the highest in elevation as well as the oldest in age. Siliclastic rocks include the Lee and Carter Caves Sandstone above the levels and the Borden Formation below the levels. Note that the color scheme is replicated throughout the chapter to differentiate Option 1 figures and tables from those of Option 2. 22

32 Figure 4. Levels associated with Option 2, consisting of five levels. Level 5 is the highest in elevation as well as the oldest in age. Siliclastic rocks include the Lee and Carter Caves Sandstone above the levels and the Borden Formation below the levels. Note that the color scheme is replicated throughout the chapter to differentiate Option 2 figures and tables from those of Option 1. 23

33 The higher resolution 10-meter DEM produced a different distribution than the 30-meter DEM used by Peterson et al. (in review). The elevations of levels found from the 10-meter DEM were consistently lower than those delineated from the 30-meter DEM. The current 10-meter DEM study found that Level 4 was between meters, Level 3 was between meters, Level 2 was between meters and Level 1 was between meters. Peterson et al. (in review) found Level 4 to be between meters, Level 3 to be between meters, Level 2 to be between meters, and Level 1 to be between meters (Table 1). At the time the past study was conducted, the contact elevation between the Upper Member of the Newman Limestone and the overlying sandstone units was not known. Furthermore, the number of caves in the initial study was greater than those used in the 10-meter DEM study. Knowing the contact elevation and the number of caves used in each analysis are the only differences in the methods for determining level elevations and therefore contribute to the differences between the ranges of level elevations. Peterson et al. (in review) reported 16% of the total caves were within Level 4, 31% of caves were within Level 3, 30% of caves were within Level 2, and 23% of caves were within Level 1. In comparison, this study found 36% of the caves within the 10-meter DEM were in Level 4, 30% were within Level 3, 25% were within Level 2, and 9% were within Level 1. The error analysis described earlier showed that the current study had a mean error that was 0.20 meters less than that reported by Peterson et al. (in review). A higher DEM resolution and less error than the 30-meter study explain why the cave level elevations found in the two studies are different. Although a 30-meter and a 10-meter DEM often come from the same data source, the 10-meter DEM is better because the smaller cell size 24

34 allows for more sampling and less generalizing of elevation values. Only a few studies compare the accuracy of 10-meter and 30-meter DEMs and much of the research performed utilized slope classification and soil surveys. For example, studies by Hammer, et al. (1995) and Zhang, et al. (1999) have both concluded that there is a measurable difference between DEMs with different spatial resolutions, and although minimal, the 10-meter DEM is an improvement over the 30-meter DEM. The results of the present study are similar to these findings. Table 1. Comparison between 30-meter DEM and 10-meter DEM results. 30-meter DEM (Peterson et al., 2011) 10-meter DEM level elevation range (m) percentage (%) of caves in level level elevation range (m) percentage (%) of caves in level level level level level There is a clear relationship between cave elevation and level development (Table 2 and Figure 5). There are more caves in the level(s) at the highest elevations and the number of caves decreases as level elevation decreases. Levels 4 and 5 contain the most caves followed in order by Level 3, Level 2, and Level 1, which contains the least amount of caves of all levels. The greatest number of caves are found within the St. Genevieve, however, there are caves found in all limestone units. Option 2, Level 5 contains 27 caves, is approximately 11 meters thick, and is within the Upper Member of 25

35 the Newman Formation. Level 4, in both options, is within the Upper Member of the Newman Formation at higher elevations and the St. Genevieve at lower elevations. Option 2, Level 4 contains 37 caves and is approximately 10 meters thick while Option 1, Level 4 contains 52 caves and is approximately 21 meters thick. Levels 3 and 2 of both options are within the St. Genevieve. Level 3 contains 44 caves and is approximately 13 meters thick while Level 2 contains 37 caves and is approximately 12 meters thick. Level 1 is mostly within the St. Louis; however, the upper boundary of Level 1 could be within the St. Genevieve. Level 1 contains 13 caves and is approximately 14 meters thick (Table 2). Level boundaries were estimated based on unit thicknesses reported by Ochsenbein (1974). The number of levels in CCSRP will be finalized after volume and time calculations are finished and the results are compared to Mammoth Cave and Cumberland Plateau level studies. That said, research concerning levels in Mammoth Cave, Cumberland Plateau, and Carter Caves have concluded that there are at least four levels present (Anthony and Granger, 2004; Granger et al., 2001; Peterson et al., in review). 26

36 Table 2. Distributions of caves and cave elevation in relation to their corresponding level. Option 1 number of caves cave elevation range (m) average cave elevation (m) cave elevation median (m) level level level level Option 2 number of caves cave elevation range (m) average cave elevation (m) cave elevation median (m) level level level level level

37 Elevation Elevation (m) Level Option 1 Option 2 Figure 5. Relationship between cave entrance and exit elevations and their associated level. The ends of the boxes represent the 25th and 75th percentiles with the solid line at the median and the dashed line at the mean; the error bars depict the 10 th and 90 th percentiles and the points represent outliers. Mean increases with age level. Numerical values can be found in Table 2. The landscape of the region encompassing the CCSRP system includes deeply incised valleys that grade to gentle plateaus at higher elevations. Caves within the Carter Caves system are located within the valley walls. Very few cave openings are found on the plateaus because the caves entrances occur where valley wall erosion has truncated passages. Additionally, the contact between the Upper Member of the Newman Formation and the overlying sandstone unit is very consistent at an elevation of 274 m. The elevation of the contact indicates that the plateaus are capped by siliciclastic rocks 28

38 (Figure 3 and Figure 4), which inhibit cave development. Levels 1 3 are contained within the steep valley walls while Levels 4 and 5 are at the top of the valleys where the gradient becomes more gentle and the valley width widens. At first glance, the Euclidean distance between the cave entrances and the streams does not appear to have a relationship with level designation (Table 3 and Figure 6). The average and median Euclidean distances tend to increase with each successive cave level. Level 2 has an average distance between streams and caves of 17 meters, Level 3 has an average distance of 18 meters, Option 1, Level 4 has an average distance of 36 meters, Option 2, Level 4 has an average distance of 32 meters, and Option 2, Level 5 has an average distance of 40 meters. The exception is Level 1, which holds a higher average than levels 2 and 3 at 20 meters. The average Euclidean distance is greatest in levels 4 and 5, which supports the hypothesis that the distance will be greatest for caves associated with the oldest level. However, the average Euclidean distances for the remaining levels (1-3) are relatively close and the distance does not decrease with elevation (age) (Table 3 and Figure 6). The ranges for the distance between caves and streams for all levels begin at 0 meters. The maximum distance range for the top most levels is 139 meters whereas the maximum distance for lower levels are within about 20 meters of each other, ranging between 81 and 64 meters. A further look at these values indicates that they reflect the valley wall morphology and the hillslope erosion processes. The lower levels contain steeper valleys and have evidence of cave collapse. The relationship between streams and cave openings cannot be explained solely by surface processes. When there were events of rapid entrenchment, water was redirected through surface lows, rock fractures, and existing phreatic passageways (Woodside, 2008). These 29

39 actions led to cave collapse in some areas. The valley geomorphology is the result of base level lowering, stratigraphy, and insufficient time for valley widening. The lack of wide, gradually sloping valleys can also be explained by a short-lived constant base level during level formation (Teller and Goldthwait, 1991). With increasing elevation there is more likelihood that erosional processes have stepped the valley wall back further from the active stream channel. The range of Euclidean distance values for the higher cave levels is the result of variation in valley cross-sectional morphology from steep-sided and canyon like to more gently sloping profiles. Table 3. Distribution of distance between caves and streams in relation to their corresponding level. Level 4 in Option 1 and Level 5 in Option 2 are the oldest levels while Level 1 of both options is the youngest level. Option 1 distance from stream range (m) average stream dist (m) stream median (m) standard deviation level level level level Option 2 distance from stream range (m) average stream dist (m) stream median (m) standard deviation level level level level level

40 Cave Distance to Stream Distance (m) Level Option 1 Option 2 Figure 6. Relationship between levels and the distance between cave and streams. The ends of the boxes represent the 25th and 75th percentiles with the solid line at the median and the dashed line at the mean; the error bars depict the 10 th and 90 th percentiles and the points represent outliers. Mean increases with age level. Numerical values can be found in Table 3. Harlan (2009) calculated the distance between streams and cave openings using the 1:24,000 National Hydrology Dataset (NHD) for stream location provided by the United States Geological Survey. After comparing the extent of these streams to the waterways identified in the field, I concluded the NHD was not detailed enough for this analysis and therefore a stream network was created from the 10-meter DEM. Harlan found the distance between streams and cave openings for Level 4 to be from meter, Level 3 to be from meters, Level 2 to be from meters and Level 1 to be from 0-54 meters. Her results indicated that caves are much further away from streams than this analysis suggests because her stream dataset contained a smaller stream 31

41 network and therefore the streams were at an overall greater distance away from cave openings. However, both projects show that the greatest distance between streams and caves is at the highest elevations. She also concluded that lower level elevations are in greater contact with the streams and the current study s findings support that. CONCLUSIONS Overall, the use of the GIS has proven successful in delineating the cave levels in a given area. The use of a 10-meter DEM improved the accuracy of the results in comparison to the earlier studies that employed 30-meter DEMs. The number of cave levels is equivocal and can be reasonably interpreted as either four or five. These findings correlate to past cave level studies performed in other karst systems in the region. Each of these studies reported a confident interpretation of four levels, but suggested that a fifth level could be present. Deciphering if there are four or five levels within CCSRP will only add to the understanding of karst development. Using the distance between cave openings and streams did not provide information concerning how many levels are present within CCSRP or where the levels are located. It did however reveal information about valley geomorphology, which provides insights concerning how the levels were exposed through river incision. Future work could build on the interpretive framework presented here as a basis for determining the timing of cave level development through geochronologic methods. A limitation of the methodology employed in this study is the resolution of the available DEMs. As LiDAR data becomes available, resolution will become less of a limitation. Cave levels separated by narrow bands of elevation that are smaller than the overall 32

42 resolution of the terrain data will not be resolved. Likewise, this method requires caves to be daylighted at multiple elevations in order to use the DEM to identify cave elevations. However if passage elevations were known, then the use of a histogram would still be applicable to determine level elevations. Furthermore, without absolute dating techniques, this method does not elucidate where cave levels are overprinted on one another by successive base levels that return to a similar elevation. The latter issue can be largely resolved by careful observation of cave passage morphology and detailed analysis of the associated landscape morphology. This method was successful at CCSRP because the sediment units are relatively flat lying. Applying this method to an area with steeply dipping beds would be more difficult because geometry would have to be considered when interpreting the histogram. Levels would no longer be horizontal and thus the natural break elevations would not be uniform throughout the site. In addition, this method also must be applied to karst areas with a thorough cave dataset in order to have enough samples for analysis. In the final analysis, DEM-based analysis of karst development has proven to be a cost effective and straightforward means of delineating the vertical evolution of karst systems. ACKNOWLEDGEMENTS The authors would like to thanks Simone Runyon and Jonathan Love, for their assistance in the field, the Wittenberg Speleological Society for providing their CCSRP database, and Carter Caves State Resort Park for providing access to the study area. 33

43 REFRENCES Andrews, W. M., Jr., 2006, Geologic Controls on Plio-Pleistocene Drainage Evolution of The Kentucky River in Central Kentucky, Series XII, Thesis 4, 11125:, Kentucky Geological Survey, University of Kentucky, p Anthony, D. M., and Granger, D. E., 2004, A Late Tertiary origin for multilevel caves along the western escarpment of the Cumberland Plateau, Tennessee and Kentucky, established by cosmogenic 26 Al and 10 Be: Journal of Cave and Karst Studies, v. 66, no. 2, p Blak, T., 2007, DEM quality assessment, in Maune, D. F., ed., Digital elevation model technologies and applications: The DEM Users Manual: Bethesda, Maryland, American Society for Photogrammetry and Remote Sensing, p Deng, Y., Wilson, J. P., and Gallant, J. C., 2008, Terrain Analysis, in Wilson, J. P., and Fotheringham, A. S., eds., The Handbook of Geographic Infromation Science: Oxford, Blackwell, p Dogwiler, T., and Wicks, C. M., 2004, Sediment entrainment and transport in fluviokarst systems: Journal of Hydrology, v. 295, p Engel, A. S., and Engel, S. A., 2009, A field guide for the karst of Carter Caves State Resort Park and the surrounding area, northeastern Kentucky, in Engel, A. S., and Engel, S. A., eds., Field Guide to Cave and Karst Lands of the United States, Karst Waters Institute Special Publication 15, Karst Waters Institute, p Florea, L. J., Paylor, R. L., Simpson, L., and Gulley, J., 2002, Karst GIS advances in Kentucky: Journal of Cave and Karst Studies, v. 64, no. 1, p

44 Granger, D. E., Fabel, D., and Palmer, A. N., 2001, Pliocene--Pleistocene incision of the Green River, Kentucky, determined from radioactive decay of cosmogenic 26 Al and 10 Be in Mammoth Cave sediments: GSA Bulletin, v. 113, no. 7, p Hammer, R. D., Young, F. J., Wollenhaupt, N. C., Barney, T. L., and Haithcoate, W., 1995, Slope class maps from soil survey and digital elevation models: Soil Science Society of America Journal, v. 59, no. 2, p Harlan, L., 2009, Expanding the conceptual model for the Carter Caves System [M.S.: Illinois State University. Janssen, R. E., 1953, The Teays River, ancient precursor of the East: The Scientific Monthly, v. 77, no. 6, p McGrain, P., 1966, Geology of Carter and Cascade Caves Area. Ochsenbein, G. D., 1974, Origin of caves in Carter Caves State Park, Carter County, KentuckyMS]: Bowling Green State University, 64 p. Palmer, A. N., 1987, Cave levels and their interpretation: The NSS Bulletin, v. 49, no. 2, p Peterson, E., Dogwiler, T., and Harlan, L., in reivew, Using GIS to identify cave levels and discern the speleogenesis of the Carter Caves karst area, Kentucky, in Proceedings Proceedings of the Karst Interest Group Workshop, Fayetteville, Arkansas (April 26-29, 2011), Fayetteville, AR, United States Geological Survey. Rhodehamel, E. C., and Carlston, C. W., 1963, Geologic History of the Teays Valley in West Virginia: Geological Society of America Bulletin, v. 74, no. 3, p

45 Teller, J. T., 1973, Preglacial (Teays) and Early Glacial Drainage in the Cincinnati Area, Ohio, Kentucky, and Indiana: Geological Society of America Bulletin, v. 84, no. 11, p Teller, T. T., and Goldthwait, R. P., 1991, The Old Kentucky River; A major tributary to the Teays River, in Melhorn, W. N., and Kempton, J. P., eds., Geology and hydrogeology of the Teays-Mahomet bedrock valley systems, Volume Special Paper 258: Boulder, CO, The Geological Society of America, p Ver Steeg, K., 1946, The Teays River: The Ohio Journal of Science, v. XLVI, no. 6, p White, W. B., 1988, Geomorphology and Hydrology of Karst Terrains, New York, Oxford University Press, 464 p.: Woodside, J., 2008, A geomorphic investigation of a longitudinal profile, sediment mobility, and abrasion within a fluiokarst system. [M.S.: Illinois State University. Zhang, X., Drake, N. A., Wainwright, J., and Mulligan, M., 1999, Comparison of slope estimates from low resolution DEMS: Scaling Issues and a fractal method for their solution.: Earth Surface Processes and Landforms, v. 24, p

46 CHAPTER III CALCULATING CAVE LEVEL DEVELOPMENT TIME WITH GIS 37

47 ABSTRACT Identifying cave levels provides insight into cave development and climatic changes that have affected a karst system over time. Cosmogenic dating has been used to interpret levels in Mammoth Cave and the Cumberland Plateau. This absolute dating technique has proven successful in determining cave paleoclimates but is expensive. The study presented here is a preliminary method to cosmogenic dating that can outline a region s speleogenesis using a Geographic Information System (GIS) and published denudation rates. The Carter Cave system in northeastern Kentucky is within the karst landscape found along the western edge of the Appalachians and contains multiple daylighted caves at various elevations along valley walls. These characteristics make the Carter Caves an ideal location to apply GIS to cave level identification and evolution as described by Jacoby et al. (in review), who identified the cave levels within the area. The authors concluded that an argument can be made for either four or five cave levels in the Carter Cave system; however, studies identified four levels in both Mammoth Cave and the Cumberland Plateau. Further analysis indicated that the fifth level formed as a result of a change in lithology rather than an event that influenced the local base level. This research is an extension of the conclusions presented by Jacoby et al. (in review). The GIS was used to calculate the volume of material lost within each level. Then, level thickness lost and published denudation rates were used to calculate the relative time required to form each level. There was not one denudation rate applicable to each level within the cave system, but the rates varied between 12 m/ma and 40 m/ma. This study concludes that the cave system took between 3.4 and 5.7 Ma to form. 38

48 INTRODUCTION AND BACKGROUND In karst systems, extended periods of static base level along with active dissolution lead to the development of large passageways. Passages that are identified at similar elevations are believed to be formed by the same event and are collectively termed a level (Palmer, 1987). Knowing the position of levels gives insight into periods of stagnant flow, revealing information about what was occurring climatically as the levels were forming. For example, static base level can be the result of global glaciations because water is limited and consumed by glaciers. Uplift is another cause of constant base level conditions. Multiple cave levels form from intermittent local base level lowering caused by changes in regional discharge (Palmer, 1987). The cave level boundary is identified where prominently horizontal passages become vertical. Understanding the duration of level development explains how long upstream events occurred. Developing a timeline of events can combine with other area studies to develop an understanding of paleoclimate and demonstrate how upstream events affect regions downstream. Engel and Engel (2009) suggest that by understanding timing, researchers can begin interpreting a region s paleoclimate and hydrologic systems. Open cavities underground are pathways for groundwater flow and storage areas for sediment. The use of cave sediment to uncover paleoclimate and hydrologic history has only been occurring in the past few decades (White, 2007). Through dating the cave sediment, geologists are able to develop a more definite history of a cave system (Anthony and Granger, 2004). When periods of static base level change to periods of rapid incision, cave sediments accumulate in abandoned cave passageways. The transition to rapid incision and the accumulation of sediment is the result of flow changes 39

49 in response to upstream conditions, as described in the paragraph above. Knowing when sediment was deposited can correlate with surface events and aid in developing a region s climate and geomorphology history. Mammoth Cave in central Kentucky (Figure 7) is an example of where successful sediment dating research has exposed information on the development of a cave system. Granger et al., (2001) developed a precise evolution of the Mammoth Cave system in relation to the incision of the Green River using cosmogenic dating of 26 Al and 10 Be isotopes in cave sediments. Their results showed incision occurred during the Pliocene- Pleistocene in response to various glacial events and the area maintained erosion rates of 2-7 meters per million years (m/my) for the past 3.5 my, despite increased river incision rates of 30 m/my during the Pleistocene. Granger et al. (2001) identified seven events that alternated between static base level and valley incision that controlled the development of the cave system. The authors concluded that as a result of multiple incision events, a minimum of four levels developed within Mammoth Cave National Park. The authors describe the presence of a fifth level; however, they did not strongly differentiate between the two levels at the highest elevations. 40

50 Figure 7. Location of Carter Caves State Resort Park (CCSRP). Located directly west of the Valley and Ridge Providence of the Appalachian Mountains (Figure 7), the Cumberland Plateau area is another heavily karstified area in Kentucky. According to Anthony and Granger (2004) this region has experienced about 180 million years of differential lowering between the sandstone units at the top of the plateau and the underlying limestone units. The differential lowering is linked to changes in the water table elevation. When the water table elevation was consistent, time allowed for the development of passages and subsequently, levels. As the water table lowered again, rapid incision would terminate level development until the water table returned to a stable elevation and the pattern would repeat itself. Anthony and Granger (2004) dated cave sediments through cosmogenic dating of 26 Al and 10 Be isotopes and found the clastic sediments in the area correlated well with known past deposition, uplift, and incision events in the area. Cave levels development correlated to incision by the 41

51 Green River and Cumberland River and occurred at times similar to those of the Mammoth Cave area. They also found that the area had a similar lithology and climate history to the Mammoth Cave system. Both systems are located within the unglaciated Ohio River Basin and their history of cave development went into the Pleistocene. While numerous work has been published on the denudation in karst systems (Balazs, 1973; Corbel, 1959, 1965; Gabrovšek, 2007; Gams, 1981; Jennings, 1985; Oleksynowa and Oleksynowa, 1971; Plan, 2005; Pulina, 1971; Smith and Newson, 1974; White, 2009), there is limited published research that examines the calculation of the volume lost within a karst system, and none of the published work uses GIS to find the amount of sediment lost within a given karst system. There have been other varieties of volume calculation studies that used GIS including applications in dam removal and storage (Roberts et al., 2007; Vijay et al., 2005), glacial volume (Bocker, 1996; Clarke et al., 2009), gully monitoring (Marzolff and Poesen, 2009), and isostatic rebound of lakes (Yang and Teller, 2005), among others. Collectively, these studies demonstrate that using GIS and DEMs for volume calculations is an innovative and successful approach. Approximately 290 kilometers east-northeast of Mammoth Cave is the Carter Cave system (Figure 1). The majority of the Carter Caves karst system is located within Carter Caves State Resort Park (CCSRP). The state park is located within Carter County, where approximately a quarter of the area is karstified (Engel and Engel, 2009). McGrain (1966), Oshsenbein (1974), Engel and Engel (2009), Peterson et al. (in review), and Jacoby et al. (in review) all discuss in detail the geology and the hydrogeology of the area. Below is a brief summary of those studies. CCSRP contains about 106 kilometers of deeply incised valleys. Cave Branch and Horn Hollow Stream are the primary 42

52 tributaries in the park. Cave Branch flows into Horn Hollow Stream, and Horn Hollow Stream eventually joins Tygarts Creek. Tygarts Creek controls the local base level and flows north to the Ohio River. The Borden Formation is the oldest formation in the park, consisting of fine-grained sandstone, siltstone, and shale. This unit is overlaid by the Newman Formation which contains the caves the area is known for. The Newman Formation is made up of the St. Louis Limestone, the St. Genevieve Limestone, and the Upper Member of the Newman Formation. Capping the Newman Formation is the Pennington Formation which contains the Lee and Carter Caves sandstones. The units at CCSRP are similar to those found at Mammoth Cave, but have a thinner unit thickness. CCSRP has not been explored to the extent of Mammoth Cave, but is an ideal location to identify cave levels because of the amount of daylighted-caves at various elevations. Cave data can be used to establish the evolution of the cave system. There are over 130 documented caves at CCSRP and over 18 kilometers of mapped passageways. Phreatic caves are located along bedding planes while vadose passages are found along vertical water routes, such as bedrock joints (Peterson et al., in review). Caves are found in all limestone units within the park, however the majority are found in the St. Genevieve Limestone. Preceding Pleistocene glaciations, the region s landscape developed rather slowly and the base level remained at a stable elevation as compared to changes in the area after the beginning of the Pleistocene (Granger et al., 2001). The base level stability is believed to have contributed significantly to the development of large upper-level trunk conduits at Mammoth Cave (Granger et al., 2001), Cumberland Plateau (Anthony and Granger, 2004), and CCSRP (Engel and Engel, 2009; Peterson et al., in review). At this 43

53 time, the headwaters of the Teays River were located on the edge of the Piedmont Plateau in North Carolina, flowing north through CCSPR and onto west-central Ohio (Janssen, 1953; Ver Steeg, 1946). Once the Pleistocene began, the region was greatly influenced by the period s glaciations even though the area is south of the glacial maximum. As glacial meltwaters incised the area, sediments accumulated in the valleys. Engel and Engel (2009) suggest that remnants of these deposits can be found in the upper levels at CCSRP (i.e. Saltpetre Cave). As changes in base level continued, caves were forming at or below the water table (White, 1988). Granger et al., (2001) and Anthony and Granger (2004) have identified similar base level changes in two separate cave systems. There is limited published information available that specifically examines CCSRP; however, the volume of research is growing. An unpublished database concerning the geographic locations of cave openings has been assembled by the Wittenberg University Speleogical Society (WUSS). Sediment entrainment dynamics and frequency of the Cave Branch and Horn Hollow systems have been studied by Dogwiler and Wicks (2004). Woodside (2008) surveyed and analyzed the surface features within Horn Hollow in order to evaluate if they were true surface features or collapsed caves. His research has helped to identify false levels and to understand the cave network. Harlan (2009) and Peterson et al. (in review) began the work of identifying cave levels within the park through relating the cave data found by WUSS to a 30-meter digital elevation model (DEM). Those authors proposed a preliminary delineation of four levels within the park. Those findings correlate to the results in Mammoth Cave and the Cumberland Plateau, which are in a region similar to CCSRP (Anthony and Granger, 2004; Granger et al., 2001). Following the methods provided by 44

54 Harlan (2009), Jacoby et al. (in review) refined level elevations using a 10-meter DEM and introduced the possibility of a fifth level. Table 4 displays the level elevations found by Jacoby, et al. (in review). Advancing the work of Jacoby et al. (in review), the objective of this study is to determine the volume of material eroded during the level development and the interval of time required for each level to develop within CCSRP. Calculating the development time provides a better understanding of the evolution of the park. These calculated times will be analyzed to see how they compare to the speleogenesis of the Mammoth Cave system and the Cumberland Plateau system and to the incision history of the Ohio River Valley. Correlation between the systems would provide insight to the role of base level changes and paleoenvironments on karst development as well as provide more insight into the complicated karst hydrogeology. A hypothesis posed in this work is that the number of cave entrances within each level correlates with the duration of time required to develop that level; that is, longer periods of static flow will result in more cave development. I assumed the number of cave openings as a proxy for passage size. I chose the number of caves entrances (exits) to be directly related to the duration of cave development because longer exposure to water results in more dissolution, and thus greater passage development and more cave openings. As the river incises through the limestone, more cave entrances will be exposed. METHODS A Geographic Information System (GIS) was used in a previous study (Jacoby et al., in review) to find and visualize the location of levels within CCSRP. The authors 45

55 referred to the levels within CCSRP as either Option 1, which consisted of 4 levels, or Option 2, which consisted of 5 levels. The difference between the two options is that Level 4, Option 1 is split between levels 4 and 5 in Option 2. Level elevations found are as follows: Level 1 is between meters, Level 2 is between 228 and 240 meters, Level 3 is between 240 and 253 meters, Level 4, Option 1 is between 253 and 274 meters, Level 4, Option 2 is between 253 and 263 meters, Level 5, Option 2 is between 263 and 274 meters (Table 4). Jacoby et al. (in review) results were used in ESRI s ArcGIS 9.3 to calculate the volume of material lost between consecutive levels. The volume calculations in conjunction with denudation rates from the literature were used to determine the time required to erode the material between each level. The following data sources were used in this analysis: latitude and longitudes of cave entrance (exit) locations provided by WUSS and a 1/3 arc second (approximately 10 meter) digital elevation model (DEM) at a 1:24,000 scale downloaded from seamless.usgs.gov. The DEM was used to calculate the area and volume of material lost between each level. According to the National Standard for Spatial Data Accuracy (NSSDA) horizontal accuracy associated with these 10 meter DEMs is approximately ± meters while the vertical accuracy is approximately ± meters (Blak, 2007). 46

56 Table 4. Level Summary Data for Options 1 and 2. Option 1 Range of Mean Cave Percentage Equivalent Level Number Volume Elevation of Caves Elevations of Caves (m 3 Area (m 2 ) thickness lost ) (m) 1 (m) (%) (m) Level ,196,336 14,135, Level ,945,389 5,969, Level ,563,967 3,052, Level ,026,737 2,472, Option 2 Range of Mean Cave Percentage Equivalent Level Number Volume Elevation of Caves Elevations of Caves (m 3 Area (m 2 ) thickness lost ) (m) 1 (m) (%) (m) Level ,014,693 8,909, Level ,181,642 5,226, Level ,945,389 5,969, Level ,563,967 3,052, Level ,026,737 2,472, Jacoby et al (in review). 47

57 To calculate area and volume with the least amount of distortion, the DEM was converted to the North America Albers Equal Area Conic projection. The level elevations from Jacoby et al. (in review) (Table 4) were used in the 3D Analysis extension of ESRI s ArcGIS 9.3 to calculate the volume and area of material lost beneath each level. 3D Analysis connects raster cell centers, creating a triangulated irregular network (TIN), and determines its contribution to area and volume. The output volume is the cubic area between a specified reference plane (or elevation) and the top of the surface (ESRI, 2010) (Figure 8a and 8b). The output volume is only a measurement of the material lost within the valleys. Note that this tool only provides the volume of material lost on the surface and does not measure the volume of material lost within the non-daylighted karst system. As illustrated in Figure 8, the volume and area of each level was calculated through subtraction as presented in Equation (1): total level volume = (volume beneath top of level) (volume beneath base of level) (1) 48

58 Figure 8. Visual depiction of how the 3D Analysis tool is used to calculate the level volume and area as represented for the study area. The GIS outputs the area and volume of the open space below a specified elevation (light gray, 2a and 2b). To find the area and volume for each level, 2a was subtracted from 2b, which gave the volume and area for each level (2c). Note that this figure is a schematic drawing and does not represent any specific location within the park. The calculation for the total thickness of material lost needs to consider the variation in topography as seen in the DEM. Therefore, calculating the difference between level elevations is not an accurate estimation of material lost and the quotient of volume over area must be used. To calculate the thickness of lost material, Equation (2) was used. Again, this value is a measurement of thickness lost within the valley, not the thickness of material lost within the existing cave passageways. Total Thickness Lost = (Level Volume) / (Level Area) (2) 49

59 Once the thickness of material lost (Table 4) was calculated, the amount of time required to remove the material was determined. Time was calculated using equation (3) (White and White, 1991). The most reasonable rate will be identified based on how the time calculations compares to regional isotopic dating studies (Table 5). Time = (Thickness Lost) / (Denudation Rate) (3) Table 5. The extent of level formation at Mammoth Cave and the Cumberland Plateau. Level A and B were crossed out because these data were estimated and not used for comparisons in this study. Note that levels in for Mammoth Cave and Cumberland Plateau are in reverse order of the designation at CCSRP. Therefore, A and 1 are the oldest and highest elevation at Mammoth Cave and Cumberland Plateau, respectively. Cave Level Mammoth Cave 1 CCSRP 2 Cumberland Plateau 3 Option 1 Option 2 Age Extent Cave Cave Age (Ma B.P.) 4 Age Age (Ma) Level Level (Ma B.P.) (Ma B.P.) (Ma B.P.) Extent (Ma) NA A B C D E Granger et al, Peterson, et al (in review) 3 Anthony and Granger, 2004, and White, Ma B.P. stands for millions of years before present. Denudation rates were obtained from the literature (Table 6). White (2009) has established a rate of 30 m/ma for the Appalachian region. However, simulations were conducted with denudation rates greater than and less than to 30 m/ma to determine the most representative rate. Denudation rates were chosen based on their common occurrence in the literature or their relationship to 30 m/ma (Table 6). There are multiple 50

60 denudation rates presented for comparison, thus allowing for an understanding of how sensitive the time calculations are to denudation rates Table 6. Table displaying chosen denudation rates and their corresponding geographic location Rate 9.5 m/ma m/ma 20 m/ma 30 m/ma 40 m/ma 50 m/ma Geographic Location Logatec Doline, Slovenia (Gams, 1981) Clare-Galway, Ireland (Jennings, 1985) Poland (Pulina, 1971) Logatec Doline (Gams, 1981) Krakow Plateau (Corbel, 1965) Aggtelekm, Hungary (Balazs, 1973) Appalachians, USA (White, 2009) Yucatan, Mexico (Corbel, 1959) Austrian Alps (L. Plan, 2005) Laboratory derived maximum rate (F. Gabrovsek, 2007) Mendips, England (Smith and Newson, 1974) Poland (Oleksyonowa and Oleksyonowa, 1969) Climate Conditions (if provided) TEMPERATE TEMPERATE TEMPERATE TEMPERATE TEMPERATE TEMPERATE TEMPERATE TROPICAL ALPINE N/A TEMPERATE TEMPERATE RESULTS Table 4 shows the volume and area calculation results for options 1 and 2. Regardless of the option designation, the volume, area, and equivalent material thickness lost for each level increases with level elevation and age. Level 1 has an estimated volume loss of 39 million cubic meters and a thickness loss of approximately 15.8 meters. Level 2 has an estimated volume loss of 62 million cubic meters and a thickness loss of approximately 20.2 meters. Level 3 has an estimated volume loss of 121 million 51

61 cubic meters and a thickness loss of approximately 20.3 meters. Level 4, Option 1 has an estimated volume loss of 400 million cubic meters and a thickness loss of approximately 28.2 meters. Level 4, Option 2 has an estimated volume loss of 146 million cubic meters and a thickness loss of approximately 28.0 meters. Level 5, Option 2 has an estimated volume loss of 253 million cubic meters and a thickness loss of approximately 28.4 meters. After using the equivalent thickness lost from Table 4 and the denudation rates from Table 6, the range of level development extent times were found (Table 6). It is possible that speleogenesis took anywhere from 1.69 Ma (at 50 m/ma) to Ma (at 9.5 m/ma) to occur (Table 7). Regional karst formation is believed to have begun after 5.6 Ma before present (B.P.) (White, 2009 and Anthony and Granger, 2006). The estimation concerning the beginning of karst formation can help narrow down an appropriate denudation rate for CCSRP. Whether the system has four or five levels present, a rate of 20 m/ma appears to fit the literature well. Considering this rate, Level 5, Option 2 took 1.42 Ma to form, Level 4, Option 2 took 1.40 Ma to form, Level 4, Option 4 took 1.41 Ma to form, Level 3 took 1.01 Ma to form, Level 2 took 1.01 Ma to form and Level 1 took 0.79 Ma to form. This equates to Option 2 taking 5.63 Ma to form and Option 1 taking 4.22 Ma to form. 52

62 Table 7. The timing of level development based rates chosen (Table 4). Geologist studying the Appalachians have found 30 m/ma (White, 2009), outlined here in bold, to represent overall denudation occurring in the area. Gray cells represent denudation rates that best fit the time of level development for the Cumberland Plateau and Mammoth Cave studies Option 1 Equivalent thickness lost (m) 9.5 m/ma 12 m/ma 20 m/ma 30 m/ma 40 m/ma Length of Time for Level Development (Ma) 50m/ Ma level level level level Total system development time possible (ma) Estimated system development time (ma) based on chosen rates: 3.38 Option 2 Equivalent thickness lost (m) 9.5 m/ma 12 m/ma 20 m/ma 30 m/ma 40 m/ma Length of Time for Level Development (Ma) 50m/ Ma level level level level level Total system development time possible (ma) Estimated system development time (ma) based on chosen rates: 5.74 The extent of level development in Mammoth Cave and Cumberland Plateau are shown in Table 5. After comparing the timing calculations to isotopic dating studies performed at Mammoth Cave and the Cumberland Plateau, it is evident that one 53

63 denudation rate is not efficient for revealing the region s speleogenesis. Taking this possibility into consideration, it appears that Level 5, Option 2 took 2.37 Ma to form at a rate of 12 m/ma, Level 4, Option 2 took 1.40 Ma to form at a rate of 20 m/ma, Level 4, Option 1 took 1.41 Ma to form at 20 m/ma, Level 3 took 0.51 Ma to form at a rate of 40 m/ma, Level 2 took 0.67 Ma to form at a rate of 30 m/ma, and Level 1 took 0.79 Ma to form at 20 m/ma. This equates to Option 2 taking approximately 5.74 Ma to form and Option 1 taking 3.38 Ma to form. These values fit well with the timing established by Anthony and Granger (2004) and Granger et al. (2001). The thickness estimations showed that the greatest volume lost within the system was at the top most levels. The timing estimations indicated that the upper levels also took the longest to form. It is important to note that levels at higher elevations were continuing to erode, even past their suggested event. For this reason, the results are partially skewed at the top most elevations because the value of thickness lost includes material lost during the formation of lower levels. In other words, the event causing the formation of Level 5, Option 2 might have been shorter than 2.37 Ma if the amount of material removed during the formation of lower levels could be eliminated from the thickness lost estimation. Although there are previous GIS volume studies (Yang and Teller, 2005 and BØcker 1996) that modeled landscape development through time, the authors did not address the possibility that surface volume lost at higher elevations occurred during the development of lower elevations. Therefore, adjusting for error caused by older levels eroding during the formation of younger levels has not been addressed. 54

64 DISCUSSION This study has indicated that one denudation rate is not sufficient for understanding CCSRP speleogenesis. At least four rates, ranging from 12 to 40 m/ma (see Table 7) have influenced this area over time. The actual denudation rate is dependent on the climate, rock characteristics and composition, as well as the amount of precipitation occurring during time of incision (White, 2009). Climate conditions varied during each level formation event and therefore finding multiple denudation rates is not surprising. However, Granger et al. (2001) established that the Appalachian area has maintained a rate of 2-7 m/ma although the river incision maintained a rate of 30 m/ma during the Pleistocene. If the denudation rates identified in this study were averaged together, a rate of approximately 24 m/ma would have been occurring during the extent of development. This value is not far from the denudation rate established by White (2009). White discussed the denudation rate as a result of various glaciation events whereas this study is attempting to specify denudation occurring between glaciation events. That detail could explain the small differences seen here. The fact that the cave development rates are not similar to area erosion indicates that cave development is more in sync with river incision than other area erosion. This is understandable because this cave system is within the valley walls of Horn Hallow and Cave Branch tributaries and both of these tributaries have contributed directly to karst development. Horn Hollow and Cave Branch both empty into Tygarts Creek which extends through most of the Appalachian karst in northern Kentucky. I expected to find the number of cave openings to correlate to the duration of level development, taking the assumptions that 1) longer periods of static flow results in more 55

65 cave development and 2) cave openings are a proxy to cave development. The amount of cave openings did not correlate well with level development time (see Table 4, Table 7, and Figure 9). The longest level development time was at 2.37 Ma for Level 5, Option 2 which only contained 27 cave openings (19% of registered caves). The shortest level development time was at 0.51 Ma for Level 3 but contained 44 cave openings (30% of registered caves). A reason for the lack of correlation is that cave openings are not a proxy to the extent of cave development and therefore are not solely representative of the volume lost within a level. Instead, the openings are more the result of fractures, weaknesses, or flow pathways within the rock than a proxy to the size or amount of existing passageways. Another reason for the insignificant correlation between level development time and cave openings present in each level could be due to the error associated with the total volume of material lost for levels at high elevations includes material lost during the formation of lower levels. This study cannot conclude that, because cave openings do not correlate well with the extent of level development, static flow does not create more caves. Levels that took the longest to develop may still contain larger or a higher frequency of passages, even though they contain a small amount of cave openings. Future research should focus on the volume of material lost within a passageway rather than simply the number of cave openings present at the surface in order to find evidence of how static flow affects the system and if a greater volume lost is directly related to development time. 56

66 Figure 9. Relationship between the number of cave opening per level (Table 4) and the estimated level development time as calculated in Table 7. The results presented in this study suggest that level formation at CCSRP is similar to the level evolution at the Cumberland Plateau (Table 5). The calculated development times closely match those of the Cumberland Plateau. The correlation could be because both areas have a similar Appalachian terrain while Mammoth Cave is on the western edge of the Appalachian Plateau. The Cumberland Plateau also has a similar contact between the karst and capping silicicalstic units. The lithology change likely contributes to a concentrated area of cave formation at the contact as water proceeds to infiltrate the limestone. The similarities between the regions are further evidence to support the presence of five levels in CCSRP. 57

67 Sediments found within the caverns of Cumberland Plateau concede that there was active sediment transport between approximately 5.7 and 3.5 Ma B.P. (Anthony and Granger, 2006). The time frame for the Cumberland Plateau supports the result of this study that the Carter Caves system was beginning to form between 5.74 and 3.38 Ma B.P. The event that contributed to the formation of Level 5, Option 2, Level 4, Option 2, or Level 4, Option 1 was not able to be determined during this study. If there is a fifth level present, its formation is possibly the result of a stratigraphic or bedrock change rather than an event causing a change in base level. Transitions from levels 4 through 1 were found by correlating calculated times to regional paleoclimate studies. Multiple authors (Anthony and Granger, 2006, Cronin, 1988, Phillips, 2009, and Teller and Goldthwait, 1991) state that sea level dropped between 3.2 and 2.0 Ma B.P. This sea level drop was due to climate cooling and growth of continental glaciers. This drop in sea level likely contributed to the transition of Level 4 (of both options) to Level 3. Global warming occurred at 3.0 Ma B.P., followed by another cooling progression at 2.4 Ma B.P. According to evidence in the Cumberland Plateau region (Anthony and Granger, 2004), this event did not last longer than about 1.5 million years. After 2.4 Ma B.P., there was a major sea regression which likely caused the tributaries to quickly incise. The transition from Level 3 to Level 2 likely occurred near 2.0 Ma B.P. during an incision pulse at Parker Strath (Anthony and Granger, 2004). Following the incision event, there was a brief pause in river base level. Prior to 1.3 Ma B.P., the transition between Level 2 to Level 1 occurred. From 1.3 Ma B.P. on, there were oscillating events between incision and base level stability. Sediments at Mammoth Cave (Granger et al., 2001) and Cumberland Plateau (Anthony and Granger, 2004) date back to 0.8 Ma B.P. 58

68 CONCLUSIONS AND FUTURE WORK This study found that volume, area, and the amount of lost material increases with level age and level elevation. Levels at higher elevations formed over a longer time period than levels at lower elevations. Longer level development appears to correlate to greater material removal, especially at high elevations. However, there needs to be caution taken with these statements since the volume of material lost for the older levels incorporates material that would have eroded during subsequent level development. There appears to be different denudation rates for various levels indicating there is not a universal rate for the system. If one denudation rate had to be chosen from this study, it would be 20 m/ma. Currently, level development appears to have begun between 3.4 and 5.7 Ma B.P. There is evidence that supports five cave levels within this system. Both the Mammoth Cave and Cumberland Plateau studies have strong evidence for four levels. However, both studies also mentioned that a fifth level was possible. I propose that the fifth level is not a result of a base level change, but a result of water flowing along a bedding plane at 274 meters, the contact between limestone and sandstone units. A limitation of this method is that it requires the results of area absolute dating studies in order to find reasonable results. Choosing the correct denudation rate with this method is difficult without guidance. In addition, the calculation of volume and area was possible for the CCSRP area because the stratigraphy is relatively flat lying. Significantly dipping beds would influence calculating the timing of development because karst development would have to be considered in relationship to structure-changing events. Furthermore, the 3D Analysis tool only calculates volume and area beneath a horizontal surface. A 59

69 significantly dipping bed would require further research into how to use GIS tools to calculate its volume and area. Challenges that are common with volume studies include quality of data, identification of boundaries, computing process time, organizing data, software expertise, and varieties within the method chosen. There is a significant future that lies ahead for volume calculations using GIS. As DEMs become more detailed and LiDAR data becomes more available, volume calculations will become more accurate. Better accuracy will encourage a wider use of GIS in volume and area calculations. The current application of GIS volume analysis is diverse ranging from urban planning to reconstructing paleoenvironments. Finding new applications for GIS area and volume calculations will only increase the versatility of this technology. This research has demonstrated one unique approach, but there are others yet to be discovered. Future work could explore how better resolution data improves analysis or how to accurately calculate volume within underground passages. Overall, this method has proven successful in estimating the amount of cave levels in a given area. The timing calculated is also consistent to other area level studies. Research in similar landscape conditions are needed to support this studies results and expand GIS applications in karst landscapes. This work contributes to the understanding of the Carter Caves system s evolution and introduces new ways of approaching karst geology. ACKNOWLEDGEMENTS The authors would like to thank the Wittenberg Speleological Society for providing their CCSRP database and CCSRP for providing access to the study area. 60

70 REFRENCES Anthony, D. M., and Granger, D. E., 2004, A Late Tertiary origin for multilevel caves along the western escarpment of the Cumberland Plateau, Tennessee and Kentucky, established by cosmogenic 26Al and 10Be: Journal of Cave and Karst Studies, v. 66, no. 2, p Balazs, D., 1973, Comparative morphogenetical study of Karst regions in the tropical and temperate zones: Transactions of the Cave Research Broup of Great Britain, v. 15, p Blak, T., 2007, DEM quality assessment, in Maune, D. F., ed., Digital elevation model technologies and applications: The DEM Users Manual: Bethesda, Maryland, American Society for Photogrammetry and Remote Sensing, p Bocker, C. A., 1996, Using GIS for Glacier Volume Calculations and Topographic Influence of the Radiation Balance. An Example from Disko, West Greenland: Danish Journal of Geography, v. 96, p Clarke, G. K., Berthier, E., Schoof, C. G., and Jarosch, A. H., 2009, Neural Networks Applied to Estimating Subglacial Topography and Glacier Volume: American Meteorological Society, v. 22, no. 8, p Corbel, J., 1959, Vitesse de l erosion.: Zeitschrift für Geomorphologie., v. 3, p. p Corbel, J., 1965, Karst de Yougoslavie et notes sur les karst tcheques et polonias: Revue Géographie de l'est, v. 5, p Dogwiler, T., and Wicks, C. M., 2004, Sediment entrainment and transport in fluviokarst systems: Journal of Hydrology, v. 295, p

71 Engel, A. S., and Engel, S. A., 2009, A field guide for the karst of Carter Caves State Resort Park and the surrounding area, northeastern Kentucky, in Engel, A. S., and Engel, S. A., eds., Field Guide to Cave and Karst Lands of the United States, Karst Waters Institute Special Publication 15, Karst Waters Institute, p ESRI, 2010, How Surface Volume (3D Analyst) works, ESRI, Inc.. Gabrovšek, F., 2007, On denudation rates in Karst: Acta Carsologica, v. 36, no. 1, p Gams, I., 1981, Comparative research of limestone solution by means of standard tablets.: 8th Int. Congress of Speleology. National Speleological Society, Huntsville, p Granger, D. E., Fabel, D., and Palmer, A. N., 2001, Pliocene--Pleistocene incision of the Green River, Kentucky, determined from radioactive decay of cosmogenic 26Al and 10Be in Mammoth Cave sediments: GSA Bulletin, v. 113, no. 7, p Harlan, L., 2009, Expanding the conceptual model for the Carter Caves System [M.S.: Illinois State University. Jacoby, B., Peterson, E. W., Kostelnick, J. C., and Dogwiler, T., in review, Journal of Cave and Karst Studies. Janssen, R. E., 1953, The Teays River, ancient precursor of the East: The Scientific Monthly, v. 77, no. 6, p Jennings, J., 1985, Karst Geomorphology, New York, Basil Blackwell Inc. Marzolff, I., and Poesen, J., 2009, The potential of 3D gully monitoring with GIS using high-resolution aerial photography and a digital photogrammetry system: Geomorphology, v. 111, no. 1-2, p

72 McGrain, P., 1966, Geology of Carter and Cascade Caves Area. Ochsenbein, G. D., 1974, Origin of caves in Carter Caves State Park, Carter County, KentuckyMS]: Bowling Green State University, 64 p. Oleksynowa, K., and Oleksynowa, B., 1971, A tentative comparison of Karst in the Tatra Mountains with Krakow-Czestochowa Plateau: Studia Geomorphologica Garpathol-Balcanica, v. 5, p Palmer, A. N., 1987, Cave levels and their interpretation: The NSS Bulletin, v. 49, no. 2, p Peterson, E., Dogwiler, T., and Harlan, L., in review, Using GIS to identify cave levels and discern the speleogenesis of the Carter Caves karst area, Kentucky, in Kuniansky, E. L., ed., Proceedings of the Karst Interest Group Workshop, Fayetteville, Arkansas (April 26-29, 2011): Fayetteville, AR, United States Geological Survey. Plan, L., 2005, Factors controlling carbonate dissolution rates quantified in a field test in the Austrian alps: Geomorphology, v. 68, p Pulina, M., 1971, Observations on the chemical denudation of some Karst areas of Europe and Asia.: Studia Geomorphologica Garpatho-Balcanica, v. 5, p Roberts, S. J., Gottgens, J. F., Spongberg, A. L., Evans, J. E., and Levine, N. S., 2007, Assessing Potential Removal of Low-Head Dams in Urban Settings: An Example from the Ottawa River, NW Ohio: Environmental Management, v. 39, no. 1, p Smith, D. I., and Newson, M. D., The dynamics of solutional and mechanical erosion in limestone catchments on the Mendip Hills, Somerset, in Proceedings Fluvial 63

73 Processes in Instrumental Watershed1974, Volume Special Publication, No.6, Institute of British Geographers, p Ver Steeg, K., 1946, The Teays River: The Ohio Journal of Science, v. XLVI, no. 6, p Vijay, R., Gupta, A., and Devotta, S., 2005, Computation of Reservoir Storage Capacity and Submergence using GIS: Surveying and Land Information Science, v. 65, no. 4, p White, W. B., 1988, Geomorphology and Hydrology of Karst Terrains, New York, Oxford University Press, 464 p. White, W. B., 2007, Cave sediments and paleoclimate.: Journal of Cave and Karst Studies, v. 69, no. 1, p White, W. B., 2009, The evolution of Appalachian fluviokarst: competition between stream erosion, cave development, surface denudation, and tectonic uplift. : Journal of Cave and Karst Studies, v. 71, no. 3, p Woodside, J., 2008, A geomorphic investigation of a longitudinal profile, sediment mobility, and abrasion within a fluiokarst system. [M.S.: Illinois State University. Yang, Z., and Teller, J. T., 2005, Modeling the History of Lake Journal of Paleolimnology, v. 33, no. 4, p

74 CHAPTER IV SUMMARY OF CONCLUSIONS 65

75 The use of GIS proved successful in delineating cave levels at CCSRP and calculating the amount of material lost between each level. The use of a 10-meter DEM did improve the accuracy of results when compared to studies conducted earlier that used a 30-meter DEM. Using the distance between cave openings and streams did not provide information about how many levels are present within CCSRP or where the levels are located. It did however give insight into valley geomorphology, which provides insights concerning how the levels were exposed through river incision. A flow chart of how this project was approached can be found in Figure 10. Volume, area, and the amount of lost material increased with level age and level elevation. Levels at higher elevations formed over a longer time period than levels at lower elevations. Longer level development appears to correlate to greater material removal, especially at high elevations. However, there needs to be caution taken with these statements since the volume of material lost for the older levels incorporates material that would have eroded during subsequent level development. There appears to be different denudation rates for various levels indicating there is not a universal rate for the system. If one denudation rate had to be chosen from this study, it would be 20 m/ma. Currently, level development appears to have begun between 3.4 and 5.7 Ma B.P. 66

76 Figure 10. Flow chart depicting datasets, processes, and outputs used in this thesis. Circles represent datasets (blue identifies datasets brought into the GIS, green identifies datasets created in the GIS, teal identifies data not used in the GIS, and the brighter green represents conclusions) while squares represent processes. 67