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Geographically, the Planinsko Polje field is one of the most preserved cultural regions of the Karstic landscape of inner Slovenia and as such a protected area of national importance. It can be recognized by its exceptional features and landmarks of material and non-material heritage and by its high-quality symbiosis of all ingredients in its space. The research of sound in the area of Planinsko Polje shows that it is an important, preserved constituent of natural and cultural heritage. Its manifestations are also interesting as indicators of its actual endangerment. Key words: sound, non-material heritage, cultural region, protected area.
The Karst Waters Institute is a non-profit 501 (c) (3) research and education organization incorporated in West Virginia. The mission of the Institute is improvement of fundamental understanding of karst water systems through sound scientific research and the education of professionals and the public.
A more accurate model of the subsurface is a two-dimensional (2-D) model where the resistivity changes in the vertical direction as well as in the horizontal direction along the survey line. Our survey was carried out by a new modern computerized static type resistivity meter, “SYSCAL Jr switch-72”. The interpretation of the 2D ?eld model was performed by the latest version of the software package “RES2DINV” version 3.54v and “RES2DMOD” version 3.01w, which perform smoothness constrained inversion using ?nite difference and ?nite elements forward modeling. The measurements were carried out by using Roll-along technique in 69 2-D soundings distributed over two pro?les. The area is characterized by quite homogenous and relatively thin recent sediments. The isopach map constructed shows generally about 10-80 m of these sediments. Excellent aquifers were detected in the Pila Spi limestones, which have wide ranges of resistivities between 22-700 ?.m due to lateral and vertical facies changes from low resistivity chalky limestone to compact high resistivity dolomite. This aquifer is buried beneath 10-80 m of sedimenst, and greater depths were detected in a few limited locations due to existence of particular structural features. The isopach map of the Pila Spi aquifer shows that thickness ranges between (20-135) m. In addition, three important structural features were identi?ed within the Pila Spi strata, a strike slip fault near Dargazen village, the “Hayasi Horst” which extends NE-SW close to Hayasi village, and a graben “Ibrahim Awa graben” close to Ibrahim Awa village. These structural features form natural obstacles below the surface and have great in?uence on the groundwater movements.
The aim of this work is to provide a synthetic outline of some of the processes of transient nature occurring in caves, focusing on poorly studied general aspects of underground physics and mainly making use of original experimental data. In the first part, the average climatic conditions of a caves, their connection to the external climate, and the general role played by rock, water, air and external morphology are discussed. The variation of the internal temperature with the altitude is a key parameter for the cave physics: the related energetic consequences are briefly discussed. In the second part, transient processes are considered, and a general overview of main meteorological phenomena occurring underground is given. The physics of thermal sedimentation, of underground temperature ranges, of infrasonic oscillations of cave atmospheres and, above all, of water vapour condensation in caves is synthetically described. The experimental study of these processes is extremely difficult, because they are time dependent and have very small amplitude; the first measurements show, however, that their variability from one cave to another, and from point to point inside a cave, is surprisingly high. To provide a more correct interpretation of underground climatic measurements, for their speleogenetic role and importance in cave environment protection, a better understanding of the processes described here is essential.
In Southwestern China, karst covers an area of 540,000 km2, and supports a population of approximately 100 million people. This groundwater can easily become highly polluted without effective management. Sound management of karst areas requires the conscientious participation of citizens including homeowners, planners, government officials, farmers and other land-use decision makers. Lingshui Spring was a good example. A series of educational materials were developed and delivered to the local government, residents, and students. A groundwater polluted accident was tracked as a natural tracer test in a spring to increase understanding of the vulnerability of the area’s karst aquifer. More than 200 people attended the communication and training course on groundwater protection and environmental justice law. Several efforts have appeared as a result, such as a proposal for Lingshui water resources protection that was put forward for the first time by Wuming county political consultative conference
Circular structures and depressions in carbonate platforms are known to represent karst chimneys or sinkholes which form as a response to rock solution. This formation mechanism is plausible for shallow-water carbonates which lie in the reach of meteoric diagenesis or fresh-water lenses. Circular structures which occur in deeper waters, however, need an alternative interpretation. Such an example of sea-floor depressions in more than 300. m deep waters occurs in the Inner Sea of the Maldives carbonate platform in the Indian Ocean. The structures were mapped with multibeam and Parasound, multi-channel seismics were used to link the depressions with structures at depth. The circular depressions have diameters of up to 3000. m and depths of up to 180. m. The craters are interpreted as pockmarks formed through the venting of gas and fluids. Gas and fluid lenses below the pockmarks are reflected by bright spots in the seismic sections as well as a reduction of the instantaneous frequency. These areas at depth are linked to chimneys connected to faults and drowned Oligocene carbonate banks. A model is presented that relates the different forms and sizes of the structures to distinct development stages of sea floor deformation to one process. Early stages of gas and fluid migration into the shallow part of the sedimentary succession induce formation of dome-shaped bodies. Initial gas and fluid escape to the sea floor is reflected by the formation of sand volcanoes and aligned small pockmarks. Active pockmarks are the deepest, and have the shape of truncated cones in cross section. Mature pockmarks are characterized by erosion of the flanks of the structure by bottom currents. Late stage pockmarks are bowl-shaped in cross section, and are to different degrees filled by drift sediments. Packages of strata revealing high reflection amplitudes and high interval velocities interpreted as microbially-mediated carbonate precipitates underlie some of the pockmarks. The pockmarks in the Maldives show that circular structures other than solution-related features can be abundant in carbonate platform deposits and that such structures may be more abundant in the geological record of carbonate platforms as previously thought. Pockmarks in the Maldives indicate that the archipelago is an example of a hydrocarbon system which consists of an isolated oceanic carbonate platform overlying a volcanic basement and lacustrine source rocks.
The hydrogeologic framework for the Floridan aquifer system was revised for eight northern coastal counties in Georgia and five coastal counties in South Carolina (fig. 1) as part of a regional assessment of water resources by the U.S. Geological Survey (USGS) Groundwater Resources Program. In this study, selected well logs were compiled and analyzed to determine the vertical and horizontal continuity of permeable zones that make up the aquifer system, and define more precisely the thickness of confining beds that separate individual aquifer zones. The results of the analysis indicate that permeable zones in the Floridan aquifer system can be divided into (1) an upper group of extremely transmissive zones that correlate to the Ocala Limestone in Georgia and the Parkers Ferry Formation in South Carolina, and (2) a lower group of zones of relatively lower transmissivity that correlates to the middle part of the Avon Park formation in Georgia and updip clastic equivalent units of South Carolina (fig. 2). This new subdivision simplifies the hydrogeologic framework originally developed by the USGS in the 1980s and helps to improve the understanding of the physical geometry of the system for future modeling efforts. Revisions to the framework in the Savannah–Hilton Head area are particularly important where permeable beds control the movement of saltwater contamination. The revised framework will enable water-resource managers in Georgia and South Carolina to assess groundwater resources in a more uniform manner and help with the implementation of sound decisions when managing water resources in the aquifer system
Many solution cavities ranging from small voids to full-size caves have no entrances and therefore no access from the surface. Geophysical methods can be used, with varying degrees of reliability, to detect such cavities and can also provide information on the bedrock/regolith interface. These methods include microgravity, electrical resistivity, audio-magnetotelluric soundings, ground-penetrating radar, shallow seismic probes, synthetic aperture radar, and thermal probes. Magnetic induction (cave radio) can provide precise locations of underground passages if they have a surface access.
Since the beginning of the 20th century, more than 150 sinkhole occurrences, mainly dropout (or covercollapse)sinkholes, have been reported in the Tournaisis area (south-eastern Belgium). Land-use planning in such a context has to take into account hazards linked with sinkhole subsidence and collapse. Management maps, drawn at a regional scale, point out zones where karstic risks have to be taken into account when dealing with infrastructure or building projects. However, karst hazard is highly variable in three dimensions at the local scale. Therefore, for such purposes, an accurate methodology is needed to detect and delineate covered karst features, especially when located in urbanized areas. As geophysical investigations are sensitive to contrasts in physical properties of soils, these methods can be useful to detect such targets. The specific karstic context encountered in the Tournaisis area strongly guides the choice of investigation techniques. Electrical resistivity imaging (ERI) methods were tested on a wellknown site where dropout sinkholes occurred formerly. This site was also studied using static cone penetration tests (CPT) and boreholes. A 3D inverted resistivity model was computed based on the 2D ERI models obtained after inversion. Resistivity profiles were extracted at each CPT location and compared to geotechnical results to determine an empirical and site-specific resistivity law that allows discrimination between weathered zones and sound limestone. Performance tests were conducted to evaluate the potential of the proposed methodology for two typical engineering problems ba
The development of karst landforms of the Aggtelek Plateau was investigated concerning the role of these valleys in the genesis of the Baradla Cave, which is located on the Plateau. New data were collected by geophysical method (Vertical Electrical Sounding) from a few dolines of a selected valley of the Aggtelek Plateau. The geophysical profiles confirm that the dolines of the valley bottom did not develop from sinkholes, but they are solution dolines. Morphological characteristics of the valleys of the Plateau suggest that these valleys are not the continuation of the valley of the recent covered karst. The former catchment area of these valleys might have been on the Plateau and north of Kecső valley. Their bottoms tilted into southern direction. Therefore the subsurface capture places of their streams might have been near to the recent sinking line.The sediments (Borsodi Gravel Formation) which were eroded from the above mentioned areas also contributed to the genesis of the Baradla Cave.
The development of karst landforms of the Aggtelek Plateau was investigated concerning the role of these valleys in the genesis of the Baradla Cave, which is located on the Plateau. New data were collected by geophysical method (Vertical Electrical Sounding) from a few dolines of a selected valley of the Aggtelek Plateau. The geophysical profiles confirm that the dolines of the valley bottom did not develop from sinkholes, but they are solution dolines. Morphological characteristics of the valleys of the Plateau suggest that these valleys are not the continuation of the valley of the recent covered karst. The former catchment area of these valleys might have been on the Plateau and north of Kecső valley. Their bottoms tilted into southern direction. Therefore the subsurface capture places of their streams might have been near to the recent sinking line.The sediments (Borsodi Gravel Formation) which were eroded from the above mentioned areas also contributed to the genesis of the Baradla Cave.
The practice of referring to certain morphologically karst-like phenomena as ‘pseudokarst’ is problematic, because it ignores basic principles of sound classification, logical naming conventions and accepted geomorphic classifications and terminology. These problems have compounded the difficulty in establishing an accepted classification of ‘pseudokarst’ types. The practice embodies a karst-centric perspective which should be avoided in favour of using conventional geomorphic terminology for non-karstic features. We illustrate this by providing existing conventional terms for many ‘pseudokarst’ types reported in the literature.
A controlled recharge event with multiple tracers was conducted on August 30, 2010. A pool adjacent to a sinkhole was filled with approximately 13,000 L of water. The water was heated, and salt, deuterium oxide, and uranine were added. The pool was then emptied into the sinkhole, and data were collected at Freiheit Spring approximately 95 m north of the sinkhole to monitor changes in discharge, temperature, conductivity/chloride, dD, uranine, and suspended sediment. This combined trace demonstrated the feasibility and utility of conducting superimposed physical, chemical, and isotopic traces. Flow peaked first at the spring and was followed by a suspended sediment peak; then essentially identical uranine, chloride, and dD peaks; and finally a temperature peak. The initial increase in flow at the spring recorded the time at which the water reached a submerged conduit, sending a pressure pulse to the spring at the speed of sound. The initial increase in uranine, chloride, and dD at the spring recorded the arrival of the recharge water. The initial change in temperature and its peak occurred later than the same parameters in the uranine, chloride, and dD breakthrough curves. As water flowed along this flow path, water temperature interacted with the aquifer, producing a delayed, damped thermal peak at the spring. The combination of conservative and nonconservative tracers illustrates unique pressure, advective, and interactive processes.
Defined in the most general way, hypogene speleogenesis is the origin of caves in which the cave-forming agency comes from depth, in contrast to epigene speleogenesis in which the cave-forming agency (meteoric recharge and its inherent or soil-derived aggressiveness) originates at the surface. A more specific definition should rely on attributes of the cave-forming agency which are most suitable and efficient for discrimination between epigene and hypogene origin of caves.
Relying on the determination of a source of the aggressiveness in distinguishing hypogene speleogenesis is the legitimate approach but it is not a methodologically sound and practically efficient one.
The hydrogeological approach and the reference to upwelling groundwater circulation in the definition of hypogene speleogenesis provide a theoretically and methodologically sound basis not only for identifying the type of speleogenesis, but also for spatial and temporal prognosis of hypogene speleogenesis.
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