This thesis presents numerical and analytical investigation of the geomechanics underlying longwall mining. It was tried out to study the disturbances induced by longwall mining in nearby rocks and their influence on the stability of the gates, pillars and main tunnels of longwall mines. The thesis consists of two major parts: numerical and analytical investigations. The study site is the Svea Nord coalmine, Svalbard, Norway. A novel algorithm was proposed for numerical simulation of the longwall mining process. In the proposed algorithm progressive cave-in and fracturing of the roof strata, consolidation of the cave-in materials and stress changes are simulated in detail. In order to outline the caved-in roof rocks a criterion based on maximum principal strain (in tension) was used. The critical tensile strain of roof cave-in was determined through back-calculation of the surface subsidence above a longwall panel at the mine. The results of the simulations were then used to analyse stress changes induced by longwall mining and the stability of gates. The simulations revealed that the stability of the gates and the loading to the rock bolts are closely related to the width of the chain pillars. With slender pillars, shear displacements along weak interlayers and bedding planes result in heavy loading to the rock bolts. Therefore, the locations of weakness zones should be taken into account in rock bolt design. The developed algorithm was implemented to study the loading and stability of the barrier pillar of the mine. The barrier pillars protect the main tunnels and border area of the mine from disturbances induced by longwall mining in the panels. The simulations show that the stresses in the barrier pillars fluctuate up and down during mining because of periodic cave-in events behind the longwall face. A failure zone of about 12 m exists in the wall of the barrier pillars. A large portion of the barrier pillar is still intact and is, thus, capable of protecting the border area. The results of the detailed simulations of longwall mining via the developed algorithm were, also, implemented in a large-scale numerical model. The model consists of all of the longwall panels and the border area of the mine. It is intended that the coal in the border area on the other side of the longwall panels will be mined after completion of the longwall mining. There is concern about how the longwall mining affects the stress state in the border area and how stress changes would affect future mining in the border area. A failure zone of about 20 m developed in the wall of the main tunnels on the side of the border area after all the longwall panels were mined out. The stress state in the remaining portion of the border area remains unchanged. Therefore, it will be possible to mine the border area in the future. In order to investigate the roof strata cave-in mechanism in detail a discontinuous numerical simulation of roof cave-in process was conducted by UDEC code. The block size in the roof strata and the mechanical parameters of the discontinuities were obtained through back-calculations. The back-calculations were conducted with a statistical method, Design of Experiment (DOE). Numerical simulations revealed that jointed voussoir beams formed in the roof strata before the first cave-in. Beam bending results in stress fluctuations in the roof strata. The maximum deflection of a roof stratum at the study site before the first cave-in is about 70% of the stratum thickness. The simulations and field measurements show no periodic weighting on the longwall shields in this mine. Numerical sensitivity analyses show, however, that periodic weighting may occur in strong roof strata. Roof strata with a high Young’s modulus and large joint spacing are not suitable for longwall mining. The maximum sustainable deflection of the roof strata before cave-in depends upon the horizontal in-situ stress state. It slightly increases with the in-situ horizontal stress in the stratum beams, but the horizontal stress would increase the possibility of rock-crushing in deflected roof beams. The implemented numerical method would be useful in assessment of the cavability of the roof strata and in selection of longwall shields with adequate load capacity. As shown through discontinuous numerical simulations, the roof strata above the underground opening constructed in the stratified rocks form voussoir beams. The stability of those beams is the major concern in the study of the gate stability and roof cave-in assessment in the longwall panels. Two different analytical methods were developed for cases with and without the in-situ horizontal stress acting along the beams. In the analytical model for the beams without horizontal stress a bilinear shape was assumed for the compression arch generated within the voussoir beams. The stability of the compression arch is governed by the energy method. The model requires an iterative procedure for convergence, and an algorithm was proposed for it. The analytical method was verified with numerical simulations by means of a discrete element code, UDEC. For the beams subjected to in-situ horizontal stress, the classic beam theory was employed to drive the analytical solution for it. The superposition method was used to obtain bending/deflection equations of the beam. The validity of both the assumptions and the developed method were, also, investigated by numerical simulations. The developed analytical method revealed that high Young’s modulus of a beam rock increases the stability of the beams against buckling but it causes higher stress within the compression arch which increases the probability of crushing failures in the beam abutments and midspan. In-situ horizontal stress along beams increases their stability against buckling and abutment sliding failure, but it raises the possibility of crushing failure at the abutments and the midspan.

Biological and chemical analysis of water samples, collected from surface and subsurface streams was preformed to determine the quantity and biologic sources of enteric contamination in the Double Springs Groundwater Basin, an urban karstified carbonate aquifer under Bowling Green, Kentucky. Major flow paths, drainage basin boundaries and geologic/hydrologic relationships were identified for the basin. Analysis of biologic contaminates using fecal coliform /fecal streptococcus counts and ratios were conducted for baseflow and storm events and related to the Double Springs hydrographs. Analysis was also conducted to determine the source of sulfides responsible for the growth of sulfur fixing bacteria in the Overflow Spring resurgence. Research findings revealed that enteric contamination concentrations were below maximum acceptable levels during baseflow condition throughout the basin. During high discharge events, bacteria levels increased and exceeded acceptable levels by 12 to 30 times. Waste was determined to be animal or human in origin depending on storm event, intensity of rain, time of year and time between events. Bacteria counts from rural sources were insignificant and were exceeded by urban bacteria counts by 1000 times. It was determined that an urban environment can have a large impact on biologic water quality in karstified aquifers. The source of sulfides in the basin was determined to be caused by migration of high sulfate water from a lower confined aquifer.

Due to recent land use changes, runoff has greatly increased In Bowling Green, necessitating the drilling of nearly 600 drainage wells to direct storm water into the Lost River Karst Aquifer. Research was conducted to (1) differentiate areas of the city as optimal for removal of storm water runoff, (2) correlate lithologic features between wells, and (3) determine optimal depths to which new drainage wells should be drilled. This was accomplished using maximum capacity tests, correlation of lithologic features between wells and comparing void density to depth below the land surface. It was only possible to develop general trends in the areal distribution of voids throughout the city, hence: specific optimal areas for removal of storm water runoff could not be differentiated. The correlation of voids between wells was possible alone both the regional dip and strike of the beds. It was also determined that the greatest potential for intersecting voids was in the first 6 meters of borehole, but no clear cut depth criteria were developed, although recommendations were made pertaining to drilling new wells to an optimal, functional depth.

Southwest of Bowling Green, Kentucky, is the Western Pennyroyal, is a karstified area which has been neglected in the study of its ground water. About 100 square miles near Adairville were chosen for analysis to help rectify this lack of knowledge. The area is dominated by Sinking Creek, a surface-subsurface drainage system. The main purpose of the study was to map the underground flow in the Sinking Creek area. The drainage system seemed to be typical for the Western Pennyroyal and exhibited many similarities to flow paths known in the Central Kentucky Karst. The investigation proved to be of basic value to future studies dealing with water well location, pollution of subsurface streams and karst-related flooding problems. The geographic scope of the study area extends from the rise of Sinking Creek to the origin of its headwaters in the residual outlying knobs of the Dripping Springs Escarpment to the north. Most of the area is a sinkhole plain developed mainly on the Ste. Genevieve and St. Louis limestones of Mississippian age. Map and field reconnaissance of the study area revealed the presence of 12 sinking streams, 6 resurgences and 5 caves, all occurring at or below 600 feet in elevation. On the basis of the physical features mentioned, two hypotheses were devised to explain their development and their relationship to the hydrology of the area. The first hypothesis was that the sinking stream and resurgences in the study area are connected in a single drainage system. This hypothesis was testable by physically determining subsurface connections in the field. The second hypothesis was that the sinking streams are controlled by the stratigraphy of the lithologic units. Diversion of surface streams occurs at or near the 600 foot elevation level, upon flowing from the Ste. Genevieve to the St. Louis limestone. This hypothesis was field tested by standard geologic methods. The determination of surface-subsurface stream connections was carried out by standard water tracing techniques using Rhodamine W.T. dye (20 percent solution) and fluorescein dye. The dye was injected into the streams, and samples were collected and then analyzed in the laboratory with a Turner fluorometer. Positive dye connections were obtained in all 5 traces. In addition to dye tracing, a large amount of field reconnaissance and subsurface mapping was necessary to determine the nature of the geologic controls on the surface-subsurface drainage system. Numerous rock outcrops and 5 caves were explored; one cave was mapped for over 4,000 feet. The lithologic studies proved to be inconclusive for the entire study area, but enough evidence was collected to support lithologic stream control in one cave stream segment. The culmination of the research design was to present the results of dye tracing and field work with a written description, graphs, and especially a map showing the connections established by the research.

This diploma thesis aims at Czech legislation related to conservation of caves both in terms of its link to the protection of caves as subterranean spaces and parts of the natural environment and of its relation to other fields of expertise, including legal studies (e.g., mining law) and other disciplines (e.g., geology, carsology). First, our attention is paid to definition of the term "cave" and to links of the term to natural sciences. Further, we analyse the development of legal conservation of caves and approaches to caves as a subject of legislation per se. The example of Slovenia - being a prominent speleological country with recognized legislation in terms of its quality and detail - is used in order to compare Czech approaches to cave conservation. Concerning the practical issues, we present an example of conservation effort devoted to one single cave in Czechia, which enables to describe functioning of legal conservation tools, including the themes where these tools overlap. We also present and discuss the only one Czech case-law dealing with the legal aspect of caves.

A field study of the lower reaches of the Long Creek drainage area in southeastern Allen County, Kentucky, established the karst character of that area. The area heretofore had been described as a non-karst area. Four swallow holes, which individually or collectively totally pirate Long Creek, were identified. Two major resurgences of the pirated flow were located and described. A detailed study of a portion of the Long Creek drainage area revealed thirty-four springs, all of which were pirated at least once, and no flow from these springs reached Long Creek by surficial routes. The field survey also revealed dolines and a major cavern, Carpenter’s Cave. The geologic formation responsible for the karst features within the Long Creek drainage area is the Louisville limestone of Silurian age. These strata are characteristically karstic wherever exposed. The impermeability of the Chattanooga shale which overlies the Louisville limestone was established by the analysis of spring piracy and resurgence. The phreatic character of the Carpenter’s Cave and other karst features led to the conclusion that these karst features were developed prior to the deposition of the impermeable Chattanooga shale during Devonian time.

In many cases in the past fish bones recovered during archaeological excavations at Upper Palaeolithic sites were often assumed to result from human activity without any consideration for alternate accumulation processes. Many of these assemblages had not been analysed in a scientifically rigorous manner, with some receiving no consideration at all. A review of current evidence and results of new analyses indicate that salmonids (salmon and trout) are the most frequently recorded fish at the European Palaeolithic cave sites. Two potential accumulation agents for fish remains were explored: brown bears (Ursus arctos) and eagle owls (Bubo bubo). Controlled feeding experiments integrated with ecological studies indicate that salmonid remains survive the digestive systems of both species and result in distinctive patterning in assemblage characteristics. Post-depositional taphonomic processes, such as trampling, also produce distinct taphonomic signatures and are an agent of differential inter-species preservation. A thorough consideration of depositional and post-depositional processes of archaeological assemblages in central Italy (Grotta di Pozzo, Maritza, La Punta and Ortucchio) and Spain (El Juyo, Altamira, Salitre, Castillo and Rascaño) shows that the fish remains from these sites result from human activity. The overrepresentation of cranial elements at the Italian sites suggest that fish were processed by removing the head to perhaps smoke or dry before transportation to other locations for consumption. This research lead to improved methods of analysis, and thus enhanced understanding of the role of fishing and fish consumption in Upper Palaeolithic hunter-gatherer societies.

Doctor of Philosophy / Department of Biology / Michael Tobler / Extremophiles are organisms with the ability to survive in environments characterized by strong physicochemical stressors lethal to most other organisms, providing excellent models to further our understanding of life's capacities and limitations to deal with far-from-average conditions. I studied how physiological processes varied among fish residing in starkly different environmental conditions to understand how organisms cope with extreme environments and disentangle the roles of short-term plastic responses and evolved population differences in shaping physiological responses. I used the Poecilia mexicana model, a series of extremophile fish populations that has colonized toxic hydrogen sulfide (H₂S) rich springs and caves, to address three major objectives: (1) I investigated the energetic consequences of life in extreme environments and tested whether predicted reductions in organismal energy demands evolved repeatedly along replicated environmental gradients. (2) I characterized variation in gene expression among populations and organs to test for interactive effects between different stressors and identify potential physiological mechanisms underlying adaptation to H₂S and cave environments. (3) I conducted common garden and H₂S-exposure experiments to test how evolutionary change and plasticity interact to shape variation in gene expression observed in nature. To address these objectives, I measured variation in metabolic physiology and quantified variation in physiological processes through genome-wide gene expression analyses. I found that adaptation to extreme environments directly impacts energy metabolism, with fish living in extreme environments consistently expending less energy overall. Reductions in energy demand have evolved in convergence and were primarily mediated through a life history shift (reduction in body mass). The quantification of gene expression across divergent habitats and organs revealed organ-specific physiological responses in H₂S-rich and cave habitats. Gene expression variation in the relevant genes was primarily shaped by evolutionary change in gene regulation, and ancestral plastic responses play a minor role in causing the observed expression differences between replicated sulfidic and nonsulfidic populations in nature. Overall, my research has implications for understanding the capacities and constraints that shape life in extreme environments and aids in our understanding of modifications in physiological pathways mediating adaptation to elevated H₂S and perpetual darkness.

Recent studies have investigated the hydrological and geochemical characteristics of karst aquifers in different settings; however, telogenetic karst aquifer processes remain poorly understood. In south-central Kentucky, the iconic Lost River Cave and Valley represents a large, complex telogenetic karst drainage basin with a series of discharge points along a collapsed section of the cave. Two Campbell Scientific® CR1000 automated dataloggers were installed at Blue Hole Four, a primary discharge point of the Lost River Karst Aquifer (LRKA). These dataloggers recorded spring discharge, water temperature, specific conductance (SpC), and pH at ten-minute intervals from January to November, 2013. During the year, data for 34 storm events were captured, including water samples that were analyzed for major cation/anion concentrations. These concentrations were correlated to SpC to yield a continuous record of ionic concentrations. Rainfall data were acquired from the Kentucky Mesonet’s Warren County Site within the LRKA basin. Dissolution rates, Ca2+/Mg2+ ratios, and a mass flux of dissolved CaCO3were calculated to assess aquifer evolution processes and identify seasonal and storm event variability throughout the year. A two end member mixing analysis (EMMA) is used to analyze storm flow conditions versus baseflow conditions, and a predictive model is presented that is used to predict peak springflow based upon rainfall totals. A detailed water budget analysis and comparison to historical data is used to assess groundwater storage and aquifer complexity. The annual data reveal both seasonal and storm event patterns in geochemical and hydrologic conditions of the aquifer. The data indicate distinct responses to storm events. These responses, as well as EMMA results, indicate that storm event flows are composed initially of water formerly stored in the aquifer flushed through the aquifer by incoming meteoric water; this gradually gives way to a mixture of meteoric water and storage water that becomes gradually more similar to pre-storm conditions as discharge recedes to baseflow levels. The highest proportion of meteoric water is coincident with the highest potential for CaCO3 dissolution, indicating that storm events drive dissolution in the LRKA. Water budgeting for the full study period and individual storm events indicate that a large proportion of water in the LRKA is not discharged at Blue Hole Four, but rather is stored in the aquifer or follows another flowpath through the aquifer. Additionally, the higher rainfall totals during storm events tend to increase the proportion of water discharged from the aquifer rather than that stored within it. The predictive model indicates a strong correlation between total rainfall and peak discharge. The results overall indicate two critical times at which contaminant transport may occur: first, any contaminants stored in the aquifer will be flushed out first with storage water as discharge peaks, followed by a period in the falling limb of the discharge hydrograph that coincides with the peak proportion of meteoric water carrying contaminants that entered the aquifer during this event. This study helps to improve understanding of telogenetic karst aquifer processes and evolution, particularly in large, complex drainage basins. Future research is necessary to understand the dynamics of these important groundwater reserves and their response to continuing pressures from climate change, human impacts, and natural processes.

L’anthropisation est la principale source de perturbations dans les grottes, et dans la grotte de Lascaux cela a entrainé la prolifération de microorganismes et des altérations de paroi menaçant sa conservation. L’objectif de cette thèse était de mieux comprendre l’écologie des microorganismes colonisant la grotte de Lascaux, en identifiant sa communauté microbienne à différentes échelles spatio-temporelles, de caractériser les facteurs qui structurent cette communauté et d’en étudier la dynamique fonctionnelle en utilisant le séquençage à haut débit d’acides nucléiques, une nouvelle approche à Lascaux. Une comparaison à l’échelle régionale de différentes grottes de Dordogne, plus ou moins anthropisées a été réalisée, puis à une échelle locale avec l’étude de salles de Lascaux, le Passage pour évaluer le rôle des substrats minéraux, et l’Abside qui présente deux types d’altérations (taches noires et zones sombres). Nos résultats montrent que les grottes anthropisées (dont Lascaux) ont des communautés microbiennes particulières. Le substrat minéral structure davantage la communauté du Passage que la présence de taches. Dans l’Abside, bien que les zones sombres soient visuellement différentes des taches noires, les communautés microbiennes présentent des similarités fortes, et notamment le rôle des interactions entre les collemboles, les champignons noirs et des bactéries. Enfin, les profils métatranscriptomiques diffèrent en fonction des salles et de la présence de taches. Ce projet a permis de caractériser l’écologie de la communauté microbienne de Lascaux et permet de mieux comprendre le fonctionnement microbien de la grotte / Anthropisation is the main source of disturbance in the caves, and in the cave of Lascaux it has led to the proliferation of microorganisms and alterations of the wall threatening its conservation.The objective of this thesis was to better understand the ecology of microorganisms colonizing the cave of Lascaux, by identifying its microbial community at different spatio-temporal scales, to characterize the factors that structure this community and to study its functional dynamics in using high throughput sequencing of nucleic acids, a new approach to Lascaux.A regional comparison of different Dordogne caves, more or less anthropised was carried out, then at a local scale with the study of Lascaux rooms, the Passage to evaluate the role of mineral substrates, and the Apse which presents two types of alterations (black spots and dark areas).Our results show that anthropogenic caves (including Lascaux) have particular microbial communities. The mineral substrate structures the Passage community more than the presence of spots. In the Apse, although dark areas are visually different from black spots, microbial communities show strong similarities, including the role of interactions between collembolans, black fungi, and bacteria. Finally, the metatranscriptomic profiles differ according to the rooms and the presence of spots.This project has made it possible to characterize the ecology of the Lascaux microbial community and to better understand the microbial functioning of the cave