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Speleology in Kazakhstan

Shakalov on 04 Jul, 2018
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

Speleology in Kazakhstan

Shakalov on 04 Jul, 2018
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

Speleology in Kazakhstan

Shakalov on 11 Jul, 2012
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

New publications on hypogene speleogenesis

Klimchouk on 26 Mar, 2012
Dear Colleagues, This is to draw your attention to several recent publications added to KarstBase, relevant to hypogenic karst/speleogenesis: Corrosion of limestone tablets in sulfidic ground-water: measurements and speleogenetic implications Galdenzi,

The deepest terrestrial animal

Klimchouk on 23 Feb, 2012
A recent publication of Spanish researchers describes the biology of Krubera Cave, including the deepest terrestrial animal ever found: Jordana, Rafael; Baquero, Enrique; Reboleira, Sofía and Sendra, Alberto. ...

Caves - landscapes without light

akop on 05 Feb, 2012
Exhibition dedicated to caves is taking place in the Vienna Natural History Museum   The exhibition at the Natural History Museum presents the surprising variety of caves and cave formations such as stalactites and various crystals. ...

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That horizontal angle is the difference in direction of two survey lines measured clockwise in a horizontal plane [25].?

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Your search for gravity (Keyword) returned 75 results for the whole karstbase:
Showing 1 to 15 of 75
A comparative integrated geophysical study of Horseshoe Chimney Cave, Colorado Bend State Park, Texas, , Brown Wesley A. , Stafford Kevin W. , Shawfaulkner Mindy , Grubbs Andy

An integrated geophysical study was performed over a known cave in Colorado Bend State Park (CBSP), Texas, where shallow karst features are common within the Ellenberger Limestone. Geophysical survey such as microgravity, ground penetrating radar (GPR), direct current (DC) resistivity, capacitively coupled (CC) resistivity, induced polarization (IP) and ground conductivity (GC) measurements were performed in an effort to distinguish which geophysical method worked most effectively and efficiently in detecting the presence of subsurface voids, caves and collapsed features. Horseshoe Chimney Cave (HCC), which is part of a larger network of cave systems, provides a good control environment for this research. A 50 x 50 meter grid, with 5 m spaced traverses was positioned around the entrance to HCC. Geophysical techniques listed above were used to collect geophysical data which were processed with the aid of commercial software packages. A traditional cave survey was conducted after geophysical data collection, to avoid any bias in initial data collection. The survey of the cave also provided ground truthing. Results indicate the microgravity followed by CC resistivity techniques worked most efficiently and were most cost effective, while the other methods showed varying levels of effectiveness.


Detection of caves by gravimetry., 1964, Chico Raymundo J.
For gravimetric investigations, a naturally occurring limestone cave may be compared with a buried empty sphere or cylinder, depending on its shape. The practical limit of detection for a subsurface void, utilizing available equipment (Worden gravity meter) and standard field procedure, is 0.1 milligal. Most corrections normally required by the gravimetric method may be neglected in cave detection, but the altitude control for the field traverse must have an accuracy of 0.1 foot. The detectability of a limestone cave, based on field work done at Luray Caverns, Virginia, and at other localities, is related to its shape, Radius (R), and distance from surface to the cave center (Z). It follows a non-linear relationship. Detectability is possible only when R3/Z2 = 4.3 feet and R3/Z = 2.89 feet. For a cave room and a cave passage respectively.

The Role of Gravity Sliding in the Development of Some Montana Caves, 1968, Campbell, Newell P.

Essays to Edward Aubrey Glennie - Aubrey Glennie and the Gravity Survey of India, 1969, Bomford G.

Specific Gravity Identification of Aragonite, 1970, Curl, Rane L.

Land subsidence in the AI-Dahr residential area in Kuwait: a case history study, 1990, Airifaiy Ia,
Four cylindrical sinkholes occurred between April 1988 and June 1989 in a residential area located 27 km south of Kuwait City. The physiographic and geological conditions of their development and the methods of survey followed to detect potential subsurface cavities in the area are discussed. The major sinkhole is 15 m in diameter and 31 m deep; the others are a few metres in size. A mechanism of migrating sinkholes is suggested, where the upper elastic sediments have been moved down into cavities of the underlying Dammam Limestone. Such movement could have been triggered by garden irrigation and urbanization. A conceptual model is introduced to explain the mechanism of this subsidence. Microgravity techniques were applied using a La Coste Model-D gravimeter to detect areas of subsurface weakness. Negative anomalies in the order of 80 microgals were recorded and considered to indicate underground cavities or zones of contrasted mass-deficiencies representing high risk areas. Moderate anomalies were also recorded and attributed to poor compaction of the ground prior to construction

CHEMICAL-REACTION PATH MODELING OF ORE DEPOSITION IN MISSISSIPPI VALLEY-TYPE PB-ZN DEPOSITS OF THE OZARK REGION UNITED-STATES MIDCONTINENT, 1994, Plumlee G. S. , Leach D. L. , Hofstra A. H. , Landis G. P. , Rowan E. L. , Viets J. G. ,
The Ozark region of the U.S. midcontinent is host to a number of Mississippi Valley-type districts, including the world-class Viburnum Trend, Old Lead Belt, and Tri-State districts and the smaller Southeast Missouri barite, Northern Arkansas, and Central Missouri districts. There is increasing evidence that the Ozark Mississippi Valley-type districts formed locally within a large, interconnected hydrothermal system that also produced broad fringing areas of trace mineralization, extensive subtle hydrothermal alteration, broad thermal anomalies, and regional deposition of hydrothermal dolomite cement. The fluid drive was provided by gravity flow accompanying uplift of foreland thrust belts during the Late Pennsylvanian to Early Permian Ouachita orogeny. In this study, we use chemical speciation and reaction path calculations, based on quantitative chemical analyses of fluid inclusions, to constrain likely hydrothermal brine compositions and to determine which precipitation mechanisms are consistent with the hydrothermal mineral assemblages observed regionally and locally within each Mississippi Valley-type district in the Ozark region. Deposition of the regional hydrothermal dolomite cement with trace sulfides likely occurred in response to near-isothermal effervescence of CO2 from basinal brines as they migrated to shallower crustal levels and lower confining pressures. In contrast, our calculations indicate that no one depositional process can reproduce the mineral assemblages and proportions of minerals observed in each Ozark ore district; rather, individual districts require specific depositional mechanisms that reflect the local host-rock composition, structural setting, and hydrology. Both the Northern Arkansas and Tri-State districts are localized by normal faults that likely allowed brines to rise from deeper Cambrian-Ordovician dolostone aquifers into shallower carbonate sequences dominated by limestones. In the Northern Arkansas district, jasperoid preferentially replaced limestones in the mixed dolostone-limestone sedimentary packages. Modeling results indicate that the ore and alteration assemblages in the Tri-State and Northern Arkansas districts resulted from the flow of initially dolomite-saturated brines into cooler limestones. Adjacent to fluid conduits where water/rock ratios were the highest, the limestone was replaced by dolomite. As the fluids moved outward into cooler limestone, jasperoid and sulfide replaced limestone. Isothermal boiling of the ore fluids may have produced open-space filling of hydrothermal dolomite with minor sulfides in breccia and fault zones. Local mixing of the regional brine with locally derived sulfur undoubtedly played a role in the development of sulfide-rich ore runs. Sulfide ores of the Central Missouri district are largely open-space filling of sphalerite plus minor galena in dolostone karst features localized along a broad anticline. Hydrothermal solution collapse during ore deposition was a minor process, indicating dolomite was slightly undersaturated during ore deposition. No silicification and only minor hydrothermal dolomite is present in the ore deposits. The reaction path that best explains the features of the Central Missouri sulfide deposits is the near-isothermal mixing of two dolomite-saturated fluids with different H2S and metal contents. Paleokarst features may have allowed the regional brine to rise stratigraphically and mix with locally derived, H2S-rich fluids

Yucatan karst features and the size of Chicxulub crater, 1996, Connors M, Hildebrand Ar, Pilkington M, Ortizaleman C, Chavez Re, Urrutiafucugauchi J, Granielcastro E, Camarazi A, Vasquez J, Halpenny Jf,
The buried Chicxulub impact structure is marked by a dramatic ring of sinkholes (called cenotes if containing water), and adjacent less prominent partial rings, which have been shown to coincide with maxima in horizontal gravity gradients and a topographic depression. These observations; along with the discreteness and spacing of the features, suggest a formation mechanism involving faulting in the outer slump zone of the crater, which would thus have a diameter of approximately 180 km, An opposing view, based primarily on the interpretation of gravity data, is that the crater is much larger than the cenote ring implies, Given the association of the known cenote ring with faults, we here examine northern Yucatan for similar rings in gravity, surface features and elevation, which we might expect to be associated with outer concentric faults in the case of a larger, possibly multiring, structure, No such outer rings have been found, although definite patterns are seen in the distribution of karst features outside the crater rim, We explain these patterns as resulting mainly from deformation related to the block fault zone that parallels the shelf edge of eastern Yucatan

Petroleum geology of the Black Sea, 1996, Robinson A. G. , Rudat J. H. , Banks C. J. , Wiles R. L. F. ,
The Black Sea comprises two extensional basins formed in a back-arc setting above the northward subducting Tethys Ocean, close to the southern margin of Eurasia. The two basins coalesced late in their post-rift phases in the Pliocene, forming the present single depocentre. The Western Black Sea was initiated in the Aptian, when a part of the Moesian Platform (now the Western Pontides of Turkey) began to rift and move away to the south-east. The Eastern Black Sea probably formed by separation of the Mid-Black Sea High from the Shatsky Ridge during the Palaeocene to Eocene. Subsequent to rifting, the basins were the sites of mainly deep water deposition; only during the Late Miocene was there a major sea-level fall, leading to the development of a relatively shallow lake. Most of the margins of the Black Sea have been extensively modified by Late Eocene to recent compression associated with closure of the Tethys Ocean. Gas chromatography--mass spectrometry and carbon isotope analysis of petroleum and rock extracts suggest that most petroleum occurrences around the Black Sea can be explained by generation from an oil-prone source rock of most probably Late Eocene age (although a wider age range is possible in the basin centres). Burial history modelling and source kitchen mapping indicate that this unit is currently generating both oil and gas in the post-rift basin. A Palaeozoic source rock may have generated gas condensate in the Gulf of Odessa. In Bulgarian waters, the main plays are associated with the development of an Eocene foreland basin (Kamchia Trough) and in extensional structures related to Western Black Sea rifting. The latter continue into the Romanian shelf where there is also potential in rollover anticlines due to gravity sliding of Neogene sediments. In the Gulf of Odessa gas condensate has been discovered in several compressional anticlines and there is potential in older extensional structures. Small gas and oil discoveries around the Sea of Azov point to further potential offshore around the Central Azov High. In offshore Russia and Georgia there are large culminations on the Shatsky Ridge, but these are mainly in deep water and may have poor reservoirs. There are small compressional structures off the northern Turkish coast related to the Pontide deformation; these may include Eocene turbidite reservoirs. The extensional fault blocks of the Andrusov Ridge (Mid-Black Sea High) are seen as having the best potential for large hydrocarbon volumes, but in 2200 m of water

The detection of cavities using the microgravity technique: case histories from mining and karstic environments, 1997, Bishop I, Styles P, Emsley Sj, Ferguson Ns,
The presence of mining-related cavities (workings, shafts and tunnels) or karstic (solution cavities and sinkholes in limestone) within the top 100 m in the rock mass restricts land utilisation, and their migration to the surface may damage property or services or cause loss of life. Confirmation of features marked on existing plans prior to design and construction may be sufficient but it is often necessary to determine the detailed sub-surface structure. The standard method of siteinvestigation is to drill a pattern of boreholes to locate the spatial extent of any cavities. However, unless the spacing is less than the cavity dimensions it is possible to miss it completely. A cavity may be filled with air, water, or collapse material resulting in a contrast in physical properties which may be detected using appropriate geophysical methods. One powerful technique is microgravity which locates areas of contrasting sub-surface density from surface measurements of the earth's gravity. Although the method is fundamentally simple, measurement of the minute variations in gravity (1 in 108) requires sensitive instruments, careful data acquisition, and data reduction and digital data analysis. Final interpretation must be performed in conjunction with independent information about the site's history and geology. This paper presents three examples in both mining and karstic environments demonstrating that microgravity is a very effective technique for detectingand delineating cavities in the sub-surface

The use of geophysical techniques in the detection of shallow cavities in limestone, MSc thesis, 1997, Walker, D. C.

Electromagnetic, resistivity and microgravity techniques were compared for their ability to delineate and resolve shallow natural cavity systems in limestone. Geophysical work was carried out at two field sites. Electromagnetic and resistivity constant-depth profiling surveys were carried out at Kitley Caves in Yealmpton, South Devon, with the purpose of determining the lateral extent of the already partially mapped system. Lower Long Chum Cave in Ribblesdale, North Yorkshire, was used as a control site for the testing of resistivity tomography and microgravity techniques. Several cavities had already been mapped at this site, and were known to be approximately cylindrical passages, with radii of 2-4m within a depth range of 5-20m, in the area to be surveyed.
At Kitley Caves, both the EM31 and resistivity surveys were carried out over a 20x30m grid, approximately 50m west of Western Ton's Quarry. The station interval for the EM31 survey was 2.5m, whereas resistivity readings were taken at 1m intervals. Both techniques identified a linear, low resistivity, anomaly orientated close to the primary joint direction. This feature is interpreted as a sediment-filled fissure, but excavation of the site would be required for verification.
The main Lower Long Chum Cave passage was also identified using EM mapping at 2.5m intervals. Four 155m lines were surveyed using resistivity tomography technique, with 32 electrodes at 5m spacing selected in a Wenner configuration. This survey successfully delineated Diccan Pot and Lower Long Churn caves in the locations and depth ranges expected, and also identified a previously unmapped feature that was interpreted as an air-filled cave or fissure 40m to the south of the main passage. The inversion process caused the features to be horizontally smeared to approximately twice their true dimensions, and in some cases anomalies from separate features were combined.
Lower Long Churn Cave was also successfully delineated using microgravity. Analysis of the residual Bouguer anomaly, combined with two dimensional forward modelling, implied a density contrast of 2.0g/cc, a radius of 2.1m and a depth of 5m. This agreed to within 2.5m with the depth given by resistivity. The position of the tunnel axis found using the two techniques differed by a maximum of 4m.
Resistivity tomography and microgravity were thus concluded to be techniques accurate in the delineation of shallow subsurface cavities. Future improvements in the latter method depend on the development of instruments that are sensitive enough to detect small changes in gravitational acceleration, whilst remaining relatively insensitive to background noise. Resistivity tomography is becoming an increasingly more valuable technique as refinements in the inversion process reduce smearing of anomalous features and improve the accuracy of the subsurface images produced.


Subsidence hazards caused by the dissolution of Permian gypsum in England: geology, investigation and remediation, 1998, Cooper Ah,
About every three years natural catastrophic subsidence, caused by gypsum dissolution, occurs in the vicinity of Ripon, North Yorkshire, England. Holes up to 35 m across and 20 m deep have appeared without warning. In the past 150 years, 30 major collapses have occurred, and in the last ten years the resulting damage to property is estimated at about {pound}1000000. Subsidence, associated with the collapse of caves resulting from gypsum dissolution in the Permian rocks of eastern England, occurs in a belt about 3 km wide and over 100 km long. Gypsum (CaS04.2H20) dissolves rapidly in flowing water and the cave systems responsible for the subsidence are constantly enlarging, causing a continuing subsidence problem. Difficult ground conditions are associated with caves, subsidence breccia pipes (collapsed areas of brecciated and foundered material), crown holes and post-subsidence fill deposits. Site investigation methods that have been used to define and examine the subsidence features include microgravity and resistivity geophysical techniques, plus more conventional investigation by drilling and probing. Remedial measures are difficult, and both grouting and deep piling are not generally practical. In more recent times careful attention has been paid to the location for development and the construction of low-weight structures with spread foundations designed to span any subsidence features that may potentially develop

Mapping Chicxulub crater structure with gravity and seismic reflection data, 1998, Hildebrand A. R. , Pilkington M. , Ortizaleman C. , Chavez R. E. , Urrutiafucugauchi J. , Connors M. , Granielcastro E. , Camarazi A. , Halpenny J. F. , Niehaus D. ,
Aside from its significance in establishing the impact-mass extinction paradigm, the Chicxulub crater will probably come to exemplify the structure of large complex craters. Much of Chicxulub's structure may be mapped' by tying its gravity expression to seismic-reflection profiles revealing an [~]180 km diameter for the now-buried crater. The distribution of karst topography aids in outlining the peripheral crater structure as also revealed by the horizontal gradient of the gravity anomaly. The fracturing inferred to control groundwater flow is apparently related to subsidence of the crater fill. Modelling the crater's gravity expression based on a schematic structural model reveals that the crater fill is also responsible for the majority of the negative anomaly. The crater's melt sheet and central structural uplift are the other significant contributors to its gravity expression. The Chicxulub impact released [~]1.2 x 1031 ergs based on the observed collapsed disruption cavity of [~]86 km diameter reconstructed to an apparent disruption cavity (Dad) of [~]94 km diameter (equivalent to the excavation cavity) and an apparent transient cavity (Dat) of [~]80 km diameter. This impact energy, together with the observed [~]2 x 1011 g global Ir fluence in the Cretaceous-Tertiary (K-T) fireball layer indicates that the impactor was a comet estimated as massing [~]1.8 x 1018 g of [~]16.5 km diameter assuming a 0.6 gcm-3 density. Dust-induced darkness and cold, wind, giant waves, thermal pulses from the impact fireball and re-entering ejecta, acid rain, ozone-layer depletion, cooling from stratospheric aerosols, H2O greenhouse, CO2 greenhouse, poisons and mutagens, and oscillatory climate have been proposed as deleterious environmental effects of the Chicxulub impact with durations ranging from a few minutes to a million years. This succession of effects defines a temperature curve that is characteristic of large impacts. Although some patterns may be recognized in the K-T extinctions, and the survivorship rules changed across the boundary, relating specific environmental effects to species' extinctions is not yet possible. Geochemical records across the boundary support the occurrence a prompt thermal pulse, acid rain and a [~]5000 year-long greenhouse. The period of extinctions seems to extend into the earliest Tertiary

Geophysical Studies at Kartchner Caverns State Park, Arizona, 1999, Lange, A. L.
Geophysical studies over Kartchner Caverns State Park mapped structure and groundwater patterns beneath valley alluvium and determined the geophysical expression of the caverns at the surface. Three techniques were employed: electromagnetics (EM), gravity, and natural potential (NP). Electromagnetic traverses in the area failed to detect the voids, owing to the very low conductivity of the carbonate rock. On the other hand, the EM method succeeded in defining the boundary between carbonate rock and alluvium, and in detecting the high-conductivity underflow beneath the drainage system. Resolution of the gravity survey over outcrop was limited to ~0.1 mgal, due to severe terrain effects. Nevertheless, two of the three major cavern passages were expressed as gravity lows at the surface, and fifteen additional small gravity anomalies could be the effect of fracture zones or unexposed caves. East of the carbonate block, the gravity profiles delineated the range-front fault and afforded interpretations of bedrock structure beneath valley fill. Natural-potential profiles, coincident with those of the gravity survey, produced a prominent compound anomaly over the mapped caverns. The 55 mV NP high was flanked by broad lows measuring ~15 mV over two of the main cavern galleries. The high was incised by a third low over a middle passage of the caverns. The lows are tentatively attributed to filtration downward toward the cave ceilings; the highs, to evapotranspiration from a deeper groundwater reservoir. Elsewhere over the outcrop, continuous NP trends are the likely expressions of faulting and fracturing, possibly accompanied by solution activity

Microgravity techniques for subsurface investigations of sinkhole collapses and for detection of groundwater flow paths through karst aquifers, 1999, Crawford N. C. . , Lewis M. A. , Winter S. A. , Webster J. A.

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