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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. ...

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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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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Featured articles from other Geoscience Journals
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
Microbial mediation of complex subterranean mineral structures, Tirato, Nicola; Torriano, Stefano F.F;, Monteux, Sylvain; Sauro, Francesco; De Waele, Jo; Lavagna, Maria Luisa; D’Angeli, Ilenia Maria; Chailloux, Daniel; Renda, Michel; Eglinton, Timothy I.; Bontognali, Tomaso Renzo Rezio
Evidence of a plate-wide tectonic pressure pulse provided by extensometric monitoring in the Balkan Mountains (Bulgaria), Briestensky, Milos; Rowberry, Matt; Stemberk, Josef; Stefanov, Petar; Vozar, Jozef; Sebela, Stanka; Petro, Lubomir; Bella, Pavel; Gaal, Ludovit; Ormukov, Cholponbek;
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Your search for resistivity (Keyword) returned 57 results for the whole karstbase:
Showing 16 to 30 of 57
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.


Geophysical surveys over karst recharge features, Illinois, USA, 2001, Carpenter Pj, Ahmed S,
Karst aquifers supply a significant fraction of the world's drinking water. These types of aquifers are also highly susceptible to pollution from the surface with recharge usually occurring through fractures and solution openings at the bedrock surface. Thickness of the protective soil cover, macropores and openings within the soil cover, and the nature of the weathered bedrock surface all influence infiltration. Recharge openings at the bedrock surface, however, are often covered by unconsolidated sediments, resulting in the inadvertent placement of landfills, unregulated dump sites, tailing piles, waste lagoons and septic systems over recharge zones. In these settings surface geophysical surveys, calibrated by a few soil cores, could be employed to identify these recharge openings, and qualitatively assess the protection afforded by the soil cover. In a test of this hypothesis, geophysical measurements accurately predicted the thickness of unconsolidated deposits overlying karstic dolomite at a site about 100 km south of Chicago, Illinois. Zones of elevated electrical conductivity and high ground-penetrating radar (GPR) attenuation within the sediments coincided with subcropping solutionally-enlarged hydraulically active bedrock fractures. These fractures extend to over 12-m depth, as shown by 2-D inverted resistivity sections and soil coring. Anomalous electromagnetic (EM) conductivity and GPR response may be due to higher soil moisture above these enlarged fractures. An epikarstal conduit at 2.5-m depth was directly identified through a GPR survey. These results suggest that surface geophysical surveys are a viable tool for assessing the susceptibility of shallow karst aquifers to contamination

Road and bridge construction across gypsum karst in England, 2002, Cooper Ah, Saunders Jm,
Gypsum karst problems in the Permian and Triassic sequences of England have caused difficult conditions for bridge and road construction. In Northern England, the Ripon Bypass crosses Permian strata affected by active gypsum karst and severe subsidence problems. Here, the initial borehole site investigation for the road was supplemented by resistivity tomography studies. The roadway was reinforced with two layers of tensile membrane material within the earth embankment. This will prevent dangerous catastrophic collapse, but will allow sagging to show where problems exist. The River Ure Bridge was constructed across an area of subsidence pipes filled with alluvial deposits. It was built with extra strength, larger than normal foundations. If one pier fails, the bridge is designed for adjacent arches to span the gap without collapse. The bridge piers are also fitted with electronic load monitoring to warn of failure. In the Midlands area of England, road construction over Triassic gypsum has required a phase of ground improvement on the Derby Southern Bypass. Here, the gypsum caps a hill where it was formerly mined; it dips through a karstic dissolution zone into an area of complete dissolution and collapse. The road and an associated flyover were built across these ground conditions. A major grouting program before the earthworks began treated the cavities in the mine workings and the cavernous margin of the gypsum mass. Within the karstic dissolution zone, gypsum blocks and cavities along the route were identified by conductivity and resistivity geophysical surveys, excavated and backfilled. In the areas of complete dissolution and collapse, the road foundation was strengthened with vibrated stone columns and a reinforced concrete road deck was used. (C) 2002 S. Yamamoto. Published by Elsevier Science B.V on behalf of NERC. All rights reserved

Deep karst conduits, flooding, and sinkholes: lessons for the aggregates industry, 2002, Lolcama J. L. , Cohen H. A. , Tonkin M. J. ,
Limestone aggregate quarries in deeply penetrating karst terrain are often at considerable risk of artesian inflow from groundwater or surface water channeled through the karstic aquifer. The inflow occurs through what are likely to be complex conduits that penetrate hundreds of feet into bedrock. Rates of inflow can exceed the operation's pumping capabilities proving to be uneconomic to manage over the long term. Over time, inflow rates can increase dramatically as turbulent flow through the conduit erodes its soft residual clay-rich fill. One recent investigation observed an inflow rate of more than 40,000 gpm from a surface water source. Floodwater persistently laden with sediment is an indicator of conduit washout and implies increasing inflow rates over time. Conduits carrying floodwater can exist in a variety of forms: along deeply penetrating geologic faults, joints, or following the path of preferentially eroded bedding. Preferential structural deformation along faults or bedding can enhance dissolution during subsequent interaction with groundwater. The resulting conduit may be a complex combination of many geological features, making the exploration and remediation of the pathway difficult. Sinkholes at the site can occur within several contexts. Pre-existing subsidence structures can reactivate and subside further, forming new collapse sinkholes within soil directly overlying the conduit. Cover-collapse sinkhole development can be a direct result of increasing downward groundwater velocities and subsurface erosion associated with the enlargement of a conduit. Normal operation events such as a quarry blast can also provide a significant new linkage between the groundwater and the quarry, allowing rapid drainage of the groundwater reservoir. With such drainage and erosion of karst-fill, sinkholes will develop over localized water table depressions, most significantly over enhanced permeability zones associated with fractures. Paradoxically, although the rise in quarry water level will lead to regional reduction in the hydraulic gradients, on local scales, drainage of the groundwater reservoir increases gradients and leads to the development of cover-collapse sinkholes. Recommended methods for preliminary site investigation can include a detailed review of geological literature and drilling logs to compile a conceptual model of the site. A fracture trace analysis with EM geophysics can confirm the locations of major faults and fractures. Fingerprinting of the various water sources to the quarry and the water in the quarry is an inexpensive and effective means of identifying the source and likely direction of the groundwater and surface water flow. Automated geophysical equipment on the market for performing rapid resistivity and microgravity surveys speeds up the site screening process during reconnaissance exploration for deep structure. It is recommended that mine planning fully incorporate this information so that quarry operators can take proactive measures to avoid catastrophic and costly flooding events. (C) 2002 Elsevier Science B.V. All rights reserved

Integrated high-resolution geophysical investigations as potential tools for water resource investigations in karst terrain, 2002, Mcgrath R. J. , Styles P. , Thomas E. , Neale S. ,
Karstic aquifers can be particularly vulnerable to both pollution from surface activities and large-scale dewatering from mineral winning operations. This is because of the enhanced vertical and lateral flow paths, resulting from the dissolution of carbonate species by rainfall. Often this process results in the development of voids that can range in size from several centimetres to several tens of metres. To date, groundwater vulnerability maps for England and Wales, including karst areas, have been produced using a methodology that does not consider the presence of karst features. The uncertainties that are presented by the potential for pollution by the presence of water-carrying conduits in karst areas, where there are proposed or existing limestone quarries, require new techniques for detecting and delineating underground cave systems. In order for any mapping technique to provide an acceptable assessment of vulnerability, the location and spatial distribution of high permeability flow paths need to be established. Of the available geophysics techniques that may allow for the identification of such features, microgravity and resistivity imaging are likely to be the most successful. Microgravity surveying has the potential to identify the presence and location of such voids, and with the integration of electrical tomographic work, can provide 'targets' for the location of monitoring boreholes. Whilst these techniques are intensive and may not be cost effective on a regional scale, they do have the potential to provide high-resolution data over smaller areas, which would be invaluable to any site or area-specific assessment of vulnerability

Effective electrode array in mapping karst hazards in electrical resistivity tomography, 2002, Zhou Wanfang, Beck Barry, Adams Angela,

Geo-electrical Investigation for Sulfur Prospecting in Teshreen Structure in Northeast Syria, 2002, Asfahani Jama, Mohamad Rand,
Electrical and structural characteristics of formations favorable for sulfur occurrences in northeast Syria are described using geo-electrical prospecting methods. Simple (VES) and combined (CVES) Schlumberger vertical electrical soundings and geo-electrical profiling using a Wenner configuration were applied to the Teshreen structure. Six profiles (A, B, C, D, E, and F) at the borders of anticlines, where positive and negative structures are joined and salt formations have a tendency to disappear, were studied. Secondary structures, characterized by high apparent resistivity exceeding 3000 Ohm.m were located on each profile using a Wenner profiling configuration. These secondary structures are demonstrated to be favorable for sulfur prospecting by both drilled wells and vertical electrical soundings. Traditional interpretation of the 84 VES measurments is supported by data from 14 CVES measurments. The CVES technique is a powerful tool, due to its improved resolution of the electrical boundaries. Thicknesses and resistivities of the Lower Al-Fares, Al-Garibeh, and Al-Dibbaneh formations were determined through the interpretation of VES measurments. The same VES measurments were then interpreted using the Pichgin method, whereby all the subsurface tectonic features were determined for depth penetration corresponding to AB/2 = 1000 m. The integration of the first and second VES phases creates a clear picture of the subsurface, including tectonic, geometric, and geo-electrical information. In summary, the sulfur occurrences in the research area are controlled by tectonic paths that are well defined by geo-electrical methods. These diverse geo-electrical methods could be used successfully for sulfur prospecting in similar environments

The situation and dynamics of the North Yorkshire windypits: A geophysical and geomorphological investigation, MSc Thesis [Engineering Geology], 2002, Devlin, R.

ub-surface slip-rift fissures and shafts, known locally as 'windypits', are numerous in the Upper Jurassic strata of the Hambleton Hills and Ryedale district of North Yorkshire. Windypits are predominantly open gull-formations, formed as a result of cambering between competent Corallian Group sandstone and limestone beds above weak clay beds of the Oxford Clay Formation. They relate to the natural pattern of steeply-dipping, widened joint-plane discontinuities, with individual blocks of caprock moving relative to one another along these surfaces. The most extensive fissure systems are up to 40m deep and over 300m long, and typically run sub-parallel to slope contours and linear topographic features, rupturing the surface above the line of maximum gradient. More complex and unpredictable structures occur where there is more than one direction of movement, resulting in a radial fissure network. Windypits have been associated with other forms of scarp recession and landslide activity, most notably the formation of unstable block detachments along vertical cliff-exposures. Aerial photographic interpretation and terrain analysis based on field observations and mapping have been used here in a detailed geomorphological investigation of windypit structures and their related landforms. They appear to play a significant role within a far more complex model of superficial slope evolution, with important consequences for rock-slope stability. The potential hazards from landslides and natural cavities are also assessed in the light of engineering geological evaluation. Shallow geophysical surveying techniques have been used to profile the electrical contrasts between void space and host rock, at a number of selected sites. It has been found that non-contacting electromagnetic conductivity methods are unsuitable for producing a discrete windypit anomaly, due to their limited depth of penetration. Tomographic resistivity techniques appear to be the most promising for accurately locating sub-surface fissures, and helping to map their true depth and full extent Comprehensive ground investigation would allow better interpretation of the geophysical data collected.


Application of electrical resistivity measurements to an evaluation of a potential landfill site in a karstic terrain, 2003, Smith , Randazzo ,

The recognition of barrage and paludal tufa systems by GPR: case studies in the geometry and correlation of Quaternary freshwater carbonates, 2003, Pedley Martyn, Hill Ian,
Tufas provide virtually the only sedimentary and proxy-environmental records within karstic terrains. However, they are difficult to access. Shallow geophysical prospecting techniques, such as resistivity and shallow seismic reflection, fail to define the often complex internal bedform details in tufa deposits and many deposits appear too well lithified to auger-sample. Nevertheless, the application of ground penetrating radar (GPR) permits the recognition of up to five distinct types of radar reflectors that can be directly related to distinct lithologies commonly seen in tufa cores: (1) well-lithified phytoherms produce sharp, sinuous and often complexly truncated bright signals; (2) soft lime muds produce subhorizontal, laterally continuous lower contrast (dull) laminar bedform signals; (3) organic-rich deposits (sapropels and peats) produce poorly focused dull responses, often with internal noise'; (4) the tops of bladed and coarse-grained deposits, such as flint gravel, give a strong bright signal; and (5) the associated presence of clay-grade lime silts and muds within the top of gravel beds produces the same top-bed signal as 4, but internal details of the deposit are masked and a remarkably homogeneous dull signal response is typical throughout the lower parts of the deposit. From these GPR responses it is possible to make meaningful three-dimensional comparisons of the internal geometries of Holocene tufa deposits. Problematic tufa deposits in the valleys of the Derbyshire Wye and the Hampshire Test, UK, are presented to illustrate the universal value of GPR surveying for fresh-water carbonate recognition and for providing key information on valley-bottom resurgence locations

Localization of saturated karst aquifer with magnetic resonance sounding and resistivity imagery, 2003, Vouillamoz J. M. , Legchenko A. , Albouy Y. , Bakalowicz M. , Baltassat J. M. , Alfares W. ,
To answer one of the main questions of hydrogeologists implementing boreholes or working on pollution questions in a karst environment-i.e., where is the ground water?-numerous tools including geophysics are used. However, the contribution of geophysics differs from one method to the other. The magnetic resonance sounding (MRS) method has the advantage of direct detection of ground water over other geophysical methods. Eight MRSs were implemented over a known karst conduit explored and mapped by speleologists to estimate the MRS ability to localize ground water. Two direct current resistivity imageries (DC-2D imagery) were also implemented to check their capability to map a known cave. We found that the MRS is a useful tool to locate ground water in karst as soon as the quantity of water is enough to be detected. The threshold quantity is a function of depth and it was estimated by forward modeling to propose a support graph to hydrogeologists. The measured MRS's signals could be used to calculate transmissivity and permeability estimators. These estimators were used to map and to draw a cross section of the case study site, which underline accurately the known karst conduit location and depth. We also found that the DC-2D imagery could underline the karst structures: It was able to detect the known cave through its associated faults. We prepared a computer simulation to check the depth of such a cave to induce resistivity anomaly which could be measured in similar conditions

The application of Time-Lapse Microgravity for the Investigation and Monitoring of Subsidence at Northwich, Cheshire, 2003, Branston Mw, Styles P,
Peter Street is an area of terraced houses in Northwich suffering from subsidence, thought to be related to salt extraction in the 19th century. Microgravity and resistivity profiling have been used as non-invasive techniques to investigate the cause of this subsidence. Repeat (or time-lapse) microgravity has been used to assess the stability and evolution of the low-density areas. Time-lapse microgravity uses the characteristics of anomaly size and gradient to track the development of cavities as they propagate to the surface. It is possible to monitor the change in gravity with time and to model the increase in cavity volume and/or depth. A gravity low was found to be coincident with the area experiencing subsidence. Integratedmodelling techniques including Euler deconvolution, Cordell & Henderson inversion and GRAVMAG modelling have been used to investigate the depth and size of the body responsible for this anomaly. Resistivity imaging has been used to investigate the conductivity of the near surface and constrain the gravity models. Results from both techniques suggest that low density ground is now present at a depth of 3-4 m below the surface in the subsidence affected area. The use of time-lapse microgravity has shown that there has been an upwardmigration of a low-density zone at gravity anomaly C over the monitoring period

Geophysical characteristics of epikarst: case studies from Zagros Mts. (Iran) and the Koneprusy region (Czech Republic), 2003, Bosá, K Pavel, Beneš, Vojtech

Characteristics of epikarst zone were studied by geophysical methods, especially refraction seismics, combined with electrical resistivity and gravimetry measurements. Applied methods were equal in both regions, so comparable results were obtained. The interpreted seismic boundaries follow the basal plane of epikarst (s.l.) and limit the epikarst zone from the geophysical point of view, i.e. zone with comparably low seismic velocities (mostly 1,000 to 3,000 m.s-1). The thickness of epikarst in the Czech Karst - the Koneprusy Devonian - is from 5 to about 60 m. The epikarst in Zagros Mts. reached up to 180 m (Cretaceous lmst.). The differences of character and vertical extent of epikarst zone depend on entirely different geological structure and geomorphological setting (relief) and evolution of both sites, which established different conditions for the release of residual stress in the limestone massifs.


Discrimination of effective from ineffective porosity in heterogeneous Cretaceous carbonates, Al Ghubar field, Oman , 2003, Smith L. B. , Eberli G. P. , Masaferro J. L. , Aldhahab S.

The Natih E heavy-oil reservoir (21j API) atAl Ghubar field, Oman has produced less than 5% of the calculated oil in place. Porosity logs used to calculate reserves show high porosity throughout the reservoir, but further analysis of the only continuous core taken from the field indicates that much of the porosity is ineffective. There are four heavily oil-stained, high-permeability skeletalpelletal grainstone units with interparticle porosity in the core that probably contributed most of the production. The four permeable grainstone units occur at the top of small-scale accommodation cycles that have wackestone and packstone bases. These grainstones make up about 20% of the total thickness of the porous Natih E reservoir. The other 80% is composed of packstone and wackestone with ineffective microporosity, interparticle porosity in burrows, and isolated moldic and intraskeletal porosity. The small-scale reservoirbearing cycles can be correlated across the field using the separation between the medium and deep induction curves as a guide. Resistivity logs are the most reliable tool to distinguish effective from ineffective porosity. Most high-permeability grainstone units have deep induction values more than 100 ohmmand separation of more than 10 ohm m between the medium and deep induction curves. The ineffective intervals with microporosity, burrow porosity, and moldic porosity have lower resistivity and little separation between the medium and deep induction curves 


Identification of karst features using seismic P-wave tomography and resistivity anisotropy measurements, 2004, Karaman Abdullah, Lar Turhan,

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