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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. ...

Did you know?

That knots is various methods of securing or tying ropes or webbing material together by cavers [13]. see also prusik knot; prusiking.?

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Karst environment, Culver D.C.
Mushroom Speleothems: Stromatolites That Formed in the Absence of Phototrophs, Bontognali, Tomaso R.R.; D’Angeli Ilenia M.; Tisato, Nicola; Vasconcelos, Crisogono; Bernasconi, Stefano M.; Gonzales, Esteban R. G.; De Waele, Jo
Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
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Your search for topographic depression (Keyword) returned 7 results for the whole karstbase:
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

Non-invasive investigation of polygonal karst features: Yorkshire Dales National Park. MSc thesis (Exploration Geophysics), 1999, Gullen T.

Resistivity, refraction and resistivity tomography methods were used to ascertain the dimensions of any sediment body present within solution dolines. Fieldwork was undertaken at two sites within the Yorkshire Dales National Park: High Mark [SD920 679] northeast of Malham Tarn, and on Ingleborough, northeast of Clapham Bottoms [SD765 722].
Results of previous studies of doline fill have been inconclusive. It has been hypothesised (Howard, unpublished) that if dolines do contain significant amounts of sediment, the fill could provide a complete palaeoenvironmental record of the Quaternary.
Resistivity studies undertaken at High Mark used an Offset Wenner array, and field data were inverted to produce a 1-D image of the subsurface. The profiles were located at the base of the doline, in the area believed to contain the greatest sediment thickness. Results suggest that the fill comprises two layers. An upper layer approximately 1 m thick is composed of poorly consolidated clayey sand with an apparent resistivity of 166m. The second layer reaches a depth of 5.6m and is more clay-rich, with an apparent resistivity of 60m. These interpretations are supported by evidence from augering. The upper 10m of limestone below the sediment has been altered during doline formation, weathering and fracturing, and has a resistivity of 220m compared to 440m for the unaltered bedrock.
Refraction profiles were undertaken at High Mark, using the hammer and plate method with a 2m geophone spacing. Profiles were located on the base, flanks and interfluves of the doline. Ground conditions prevented the acquisition of very long offset shots (>10m), and lack of these data hindered interpretation. Profiles undertaken at Ingleborough used an explosive shot placed in a 45cm-deep hole, and a 5m geophone spacing was used. Profiles were located at the base of the dolines.
Results at High Mark suggest that the limestone is overlain by 4m of sediment. The upper layer has a velocity of approximately 0.50m/ms, whereas that of the second layer is 1.19m/ms. Alteration of the upper 6m of the bedrock is indicated by a velocity of 2.00m/ms, compared to 2.99m/ms for the unaltered limestone. The bedrock surface is undulatory, possibly indicating the effects of preferential dissolution or glacial activity.
Results of the refraction surveys at Ingleborough indicate that the limestone is overlain by a single 4m-thick layer of sediment with a velocity of 0.52m/ms. Beneath this, the upper 13m of limestone is altered, with a velocity of 2.45m/ms, which increases to 3.75m/ms in the unaltered limestone below. Velocities obtained are lower than expected, but reliable imaging of the limestone was ensured by siting the profiles close to observed rock exposures. Refraction interpretations indicate that the centre of the doline is not coincident with the position predicted from observation of the surface morphology.
Resistivity tomography profiles were undertaken at the base of the dolines at both sites. A fully automated system employing a Wenner array with 25 electrodes at 5m spacings was used, and six levels were recorded. The field data were inverted and the results suggest that there are about 12.5m of sediment in the High Mark doline. The sediment is underlain by 2m of altered limestone and the bedrock base of the doline is relatively smooth.
In contrast, the thickness of sediment fill in the Ingleborough dolines is 7.5m, but the depressions are bounded by a greater thickness of altered limestone (10m). In places the limestone imaged appears to reach the surface, but is not observed in the field, indicating that minimal sediment cover is not imaged. The surface of the limestone is pitted by smaller sediment-filled depressions, possibly a feature of glacial scour.
Two profiles were forward modelled to test the reliability of the inversion model. The models were similar, but features were displaced to the right of the true section. Synthetic models were constructed to test geological hypotheses concerning the composition of the dolines. The models suggested that the dolines are relatively shallow (<12m) and are underlain by significant thicknesses of altered limestone (~10m).
The combination of results obtained suggests that dolines are not filled by significant quantities of sediment and, consequently, they cannot be used as palaeoenvironmental indicators of the Quaternary.
Jobling A. 2000. Resistivity tomography survey over a topographic depression, West Yorkshire.
BSc thesis (Geophysical Sciences), School of Earth Sciences, University of Leeds, Leeds, LS2 9JT, UK.
Three resistivity profiles were completed across a topographic depression near Garforth, West Yorkshire. The depression is roughly circular, with a radius of approximately 20m. Two profiles ran through the centre of the depression, with a third profile lying outside it. Data from these three profiles were processed, and graphs and pseudosections were compiled. The data were also inverted.
The pseudosections and inversions both showed a large, negative resistivity anomaly centred approximately beneath the surface depression. This anomaly had a resistivity difference of between 600m and 700m compared to that of the surrounding rock.
The most likely reason for this anomaly is dissolution of limestone causing development of a doline or sinkhole. The chance of the depression being an old coal mine or sand mine working has been dismissed due to the location of the site and the nature of the resistivity anomaly.


Thesis Abstract: Resistivity tomography survey over a topographic depression, West Yorkshire, 2000, Jobling A.

Resistivity tomography survey over a topographic depression, West Yorkshire. BSc Thesis,, 2000, Jobling, A.

Three resistivity profiles were completed across a topographic depression near Garforth, West Yorkshire. The depression is roughly circular, with a radius of approximately 20m. Two profiles ran through the centre of the depression, with a third profile lying outside it. Data from these three profiles were processed, and graphs and pseudosections were compiled. The data were also inverted.
The pseudosections and inversions both showed a large, negative resistivity anomaly centred approximately beneath the surface depression. This anomaly had a resistivity difference of between 600m and 700m compared to that of the surrounding rock.
The most likely reason for this anomaly is dissolution of limestone causing development of a doline or sinkhole. The chance of the depression being an old coal mine or sand mine working has been dismissed due to the location of the site and the nature of the resistivity anomaly.


Chemical and physical controls on waters discharged from abandoned underground coal mines, 2001, Lopez D. L. , Stoertz M. W. ,
Abandoned up-dip drift mines in high-sulphur coal are a major source of acid mine drainage (AMD) in Appalachia. Studies of mines in the Monday Creek watershed of southeastern Ohio show that mines are recharged by surface runoff into subsidence features that dilate the natural stress-relief fracture system. The direct connection between the ground surface and the mines leads to a rapid response in the hydrograph, with a one- to four-day lag between precipitation and corresponding peak mine discharge. Subsidence occurs in topographic depressions where overburden is presumably relatively thin. Subsidence features drain 20-36% of the surface area. Unsaturated storage appears to be volumetrically insignificant, so that far more recharge occurs than the 5% often assumed for this region. Mine storage can change rapidly due to subsidence recharge. Hydrologically, mines with subsidence features behave like karst systems, with meteoric quickflow' representing more than 50% of the total flow. Mine discharge concentrations are relatively uniform through time, suggesting either equilibrium controls on chemistry or drainage of a well-mixed pool, or both. Evidence of dilution by high flows is slight. The first high flows after a baseflow period show only a slight increase in concentrations, attributed to flushing of stored reaction products. Loadings (concentrations x flow) depend on volumetric discharge and as a consequence are highly variable. The Eh/pH environment in up-dip drift mines indicates that mine waters are in contact with the atmosphere at least part of the time, unlike a true groundwater. Iron buffering partly controls pH, which clusters around values of 3.6-5.0

Application of matrix analysis in delineating sinkhole risk areas along highway (I-70 near Frederick, Maryland), 2003, Zhou W. F. , Beck B. F. , Adams A. L. ,
Sinkhole collapse in the area of Maryland Interstate 70 (I-70) and nearby roadways south of Frederick, Maryland, has been posing a threat to the safety of the highway operation as well as other structures. The occurrence of sinkholes is associated with intensive land development. However, the geological conditions that have been developing over the past 200 million years in the Frederick Valley control the locations of the sinkholes. Within an area of approximately 8 km(2), 138 sinkholes are recorded and their spatial distribution is irregular, but clustered. The clustering indicates the existence of an interaction between the sinkholes. The point pattern of sinkholes is considered to be a sample of a Gibbsian point process from which the hard-core Strauss Model is developed. The radius of influence is calculated for the recorded sinkholes which are most likely to occur within 30 m of an existing sinkhole. The stochastic analysis of the existing sinkholes is biased toward the areas with intensive land use. This bias is adjusted by considering (1) topography, (2) proximity to topographic depressions, (3) interpreted rock formation, (4) soil type, (5) geophysical anomalies, (6) proximity to geologic structures, and (7) thickness of overburden. Based on the properties of each factor, a scoring system is developed and the average relative risk score for individual 30-m segments of the study area is calculated. The areas designated by higher risk levels would have greater risk of a sinkhole collapse than the areas designated by lower risk levels. This risk assessment approach can be updated as more information becomes available

Sinkholes, pit craters, and small calderas: Analog models of depletion-induced collapse analyzed by computed X-ray microtomography, 2014, Poppe S. , Holohan E. P. , Pauwels E. , Cnudde V. , Kervyn M.

Volumetric depletion of a subsurface body commonly results in the collapse of overburden and the formation of enclosed topographic depressions. Such depressions are termed sinkholes in karst terrains and pit craters or collapse calderas in volcanic terrains. This paper reports the first use of computed X-ray microtomography (?CT) to image analog models of small-scale (~< 2 km diameter), high-cohesion, overburden collapse induced by depletion of a near-cylindrical (“stock-like”) body. Time-lapse radiography enabled quantitative monitoring of the evolution of collapse structure, velocity, and volume. Moreover, ?CT scanning enabled non-destructive visualization of the final collapse volumes and fault geometries in three dimensions. The results illustrate two end-member scenarios: (1) near-continuous collapse into the depleting body; and (2) near-instantaneous collapse into a subsurface cavity formed above the depleting body. Even within near-continuously collapsing columns, subsidence rates vary spatially and temporally, with incremental accelerations. The highest subsidence rates occur before and immediately after a surface depression is formed. In both scenarios, the collapsing overburden column undergoes a marked volumetric expansion, such that the volume of subsurface depletion substantially exceeds that of the resulting topographic depression. In the karst context, this effect is termed “bulking”, and our results indicate that it may occur not only at the onset of collapse but also during progressive subsidence. In the volcanic context, bulking of magma reservoir overburden rock may at least partially explain why the volume of magma erupted commonly exceeds that of the surface depression.


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