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KarstBase a bibliography database in karst and cave science.
Featured articles from Cave & Karst Science Journals
Characterization of minothems at Libiola (NW Italy): morphological, mineralogical, and geochemical study, Carbone Cristina; Dinelli Enrico; De Waele Jo
Chemistry and Karst, White, William B.
The karst paradigm: changes, trends and perspectives, Klimchouk, Alexander
Long-term erosion rate measurements in gypsum caves of Sorbas (SE Spain) by the Micro-Erosion Meter method, Sanna, Laura; De Waele, Jo; Calaforra, José Maria; Forti, Paolo
The use of damaged speleothems and in situ fault displacement monitoring to characterise active tectonic structures: an example from Zapadni Cave, Czech Republic , Briestensky, Milos; Stemberk, Josef; Rowberry, Matt D.;
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 tunnels (Keyword) returned 31 results for the whole karstbase:
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Many lava tunnels are found in the Western District of Victoria, associated with volcanic eruptions of Pleistocene to Recent age, and some are probably only a few thousand years old. All Australian volcanoes are now extinct, but the most recently active were probably erupting up to 5,000 years ago, that is after the arrival of the Australian aboriginal. The newness of the Victorian caves results in original features being preserved in fine detail. All known lava caves have now been surveyed, mainly by members of the Victorian Cave Exploration Society.
The Kelly Hill caves in soft, homogenous, extremely porous dune limestone differ markedly in morphology from those in the more usual, dense, bedded limestones. Solution occurs at depth with great lateral spread through swamps overflowing into the base of the hill. Development occurs by roof breakdown as areas of solution become so large that the roof cannot support the weight; a theory of the mechanics is presented. Domes and tunnels of collapse rise above the watertable; at maturity there are isolated infalls from the surface. Water percolating down from the surface only builds secondary calcite deposits.
Surface features reflect not only the importance of cave collapse, but also the action of present and inherited zonal processes. The rates of geomorphological evolution are compared (main data in table 1). The particularities of hydrological flow are studied, as well as the dynamic of some karstic lakes, particularly the Banyoles Lake (Catalonia). The various processes generate numerous hazards enumerated in the paper and evident in urban and suburban areas and in the civil engineering works such as tunnels, dams, etc.
Karst may become a very serious disaster in tunneling if there is no prediction or warning. We developed an expert system, based on expertise of Chinese experts in karst science and in underground engineering, for prediction of karst debacles when a tunnel is excavated through a carbonate rock area. This system has been demonstrated and affirmed by domain experts
This study aims to define the karst related problems that may arise during the implementation of three weir and two dam projects planned in the Lower Zamanti Basin. Based on the regional hydrogeological investi-gations, the problems that may arise during the construction phase were outlined and relevant investigation techniques were proposed. This study showed that no water leakage problem is expected in the reservoir areas of Çamlıca II , Çamlıca III, Tatlar weirs and Göktaş dam, while the possibility of leakage thorugh the reservoir of the Topraktaş dam should be investigated by means of geophysical surveys and exploratory boreholes. The same suggestions are also va¬lid for the energy tunnels of Çamlıca II, Tatlar weirs and Göktaş dam where dewatering of karst groundwater would be an important problem.
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
Karstified Middle Miocene sediments are widely exposed in northern Iraq particularly in the area surrounding the city of Mosul. The unit is dominated by gypsum and exposed in thirteen anticlinal structures within the investigated area of about 1600 square kilometers. Synclines, though containing the same sequence, are not karstified due to a Quaternary cover. Karst features were located from air photos: Over 4000 were recorded, the smallest detectable being two meters in diameter. The majority are sinkholes (dolines), developed in gypsum and manifested in the overlying collapsing limestone. They are singular, in lines or clusters. Shafts and karren are fewer in number and are usually developed in uncovered gypsum. Sinkholes are visibly located along fractures and at fracture intersections over gently inclined limestone beds overlying the gypsum. Two karst systems were identified, an active and recent system characteristic of all the anticlinal structures and an older (Pleistocene) fossil karst system characteristic of Alan, Ishkaft, Albu Saif and Hammam structures. The fossil karst system is preserved on remnant elevated old land surfaces and produces characteristic tight undulations in the limestone due to collapse inwards in sinkholes and elongated tunnels formed along a series of sinkholes. The fracture study of anticlinal structures reveals that the mean fracture density per area ranges between 4 and 8 (km/km2) and shows a unimodal character for most of the structures. However the distribution of karst in relation to fractures is bimodal for at least half of the structures with mean values ranging from 4.5 to 11 (km/km2). The fractures in the anticlines are thought to have formed due to folding but some are associated with major lineaments cross cutting the structures, which is reflected in the bimodality and the crude unimodal fracture/karst distribution. Karst features are related to the general fracture pattern but are more localized in densely fractured areas. Karst areas were also found to correlate with lower slope gradient and lower drainage density
Spectacular rock formations have developed in coarse, poorly sorted conglomerates and arkosic sandstones at Hopewell Rocks in the Bay of Fundy, which has the largest tidal range in the world. The average gradient of the shore platform is 3.2 degrees, although it varies because of slight differences in rock hardness. Schmidt Rock Test Hammer measurements show that the rock is generally no more resistant in 16 stacks and in one stack-arch than in the adjacent platform and cliff. Most stacks, arch-tunnels and caves in this area result from dissection of the rock mass along prominent, well-spaced joint planes. Old photographs suggest that the stacks at Hopewell Rocks may have developed in the :Last 100 to 250 years. Notches are ubiquitous at the cliff foot, and they are responsible for the characteristic mushroom-shaped appearance of the stacks. Although there is no consistent relationship between the depth of notches on the seaward and landward sides of the stacks, the notches are at higher elevations on the seaward side. The deepest part of most notches is a little below the mean high tidal level, although several are up to 1 or 2 m below it, especially on the landward side of stacks. Stack morphology and notch depth change in a fairly predictable manner through time, as the stacks become increasingly isolated from the cliff. (C) 1998 John Wiley & Sons, Ltd
Based on the analyses and comparisons of water chemistry, stable carbon isotopes and deposition rates of speleothems, the authors found that there are two kinds of speleothems in the tunnels at the Wujiangdu Dam site, Guizhou, China, namely the CO2-outgassing type and the CO2-absorbing type. The former is natural, as observed in general karst caves, and the product of karst processes under natural conditions. The latter, however, is special, resulting from the carbonation of a cement-grouting curtain and concrete. Due to the quick absorption of CO2 from the surrounding atmosphere, evidenced by the low CO2 content in the air and the high deposition rate of speleothems (as high as 10 cm/a) in the tunnels, the contribution of the carbonation process to the sink of CO2 in the atmosphere is important tin the order of magnitude of 10(8) tons c/a) and should be taken into consideration in the study of the global carbon cycle because of the use of cement on a worldwide scale
The Ljubljanica is a typical sinking river, disappearing and reappearing on the surface seven times. Data from 1534 surveyed caves in the central part of the basin have been processed statistically. Fragments of horizontal caves are grouped in clearly expressed clusters. At least two of the clusters appear to have been separated apart along the Idrija strik-slip fault and displaced about 12 km. The spatial orientation of the clusters only vaguely fits the present hydrogeological situation, and it is suggested that the caves are relict or re-occupied voids that formed originally in circumstances different from those of today. Most of the caves have typical phreatic shapes, which are further modified into epiphreatic channels only where there has been considerable input of mechanically transported material. The general genetic pattern is: initiation along bedding planes; penetration into joints; expansion by collapse of crushed zones and along faults; filling of lower parts of the system with sediments and transformation into epiphreatic tunnels.
Coalfields in North China encompassing than ten Provinces contain six to seven coal seams in the Permo-Carboniferous strata. The lower three seams, accounting for 37% of the total reserves , are threatened with karst water from the underlain Ordovician limestone. Hundreds of water inrush incidences have occurred in which a large amount of water suddenly flows into tunnels or working faces under high potentiometric pressure 20 years. Large-scale dewatering or depressurizing of the karst aquifer was considered essential to water inrushes and keep the mines safely operational. This practice has caused sinkholes, dry gs, water supply shortage, and groundwater Keywords Geological barrier contamination in the surrounding areas, which is environmentally not permitted. One of the alternative water control measures is to make full use of the layer between the coal seam and the karst er as a geological barrier. Similar to the application in the nuclear industry where a geological barrier of this application is considered a hydraulic barrier as well with the objective to prevent or constrain water flow from the underlying aquifer into mines. Its effectiveness to constrain water flow is described by a parameter referred to as hydrofracturing pressure (P-hf) When the water pressure in the underlying aquifer exceeds P-hf, a wedging effect takes place within the fractures of the geological barrier and, as a result, water inrush occurs. In-situ hydrofracturing tests were used to determine P-hf in bauxite and silty sandstone at tunnels. The P-hf in the silty sandstone is larger than that in the bauxite but they both vary with depth (distance from the bottom of the tunnel). Based on the test results, a new safety criterion for water inrush was derived for mines and it has been successfully applied to mining practices with the minium effort of dewatering in the karst aquifer. The same criterion can also be applied to tunneling and quarrying in areas with similar geological conditions
Considering all man-made structures in karst areas, dams, reservoirs and tunnels are the most vulnerable in relation to induced subsidence and caverns. Reservoirs that are located entirely or partially on karstified rocks covered with unconsolidated sediments are especially subsidence-prone. As a consequence of induced subsidence a number of reservoirs in karst areas failed and were never fully filled. Such subsidence formation is very damaging because the development is unpredictable and practically instantaneous. Reservoirs in karst areas may fail to fill despite an extensive site investigation programs and sealing treatment. Every problem is unique and past experiences are never repeated. This review focuses on the meaning and consequences of selected prominent examples, but the conclusions reached are valid for subsidence problems related to man-made structures in general.
The gypsum caves of western Oklahoma are situated in three separate areas of evaporite karst: (1) the Cimarron Gypsum Hills, in the northwest, along the Cimarron River; (2) the Weatherford Gypsum Hills, in west-central Oklahoma, to the north of the Wichita Mountains; and (3) the Mangum Gypsum Hills, in the southwest, west of the Wichita Mountains. Caves of the Cimarron Gypsum Hills and the Mangum Gypsum Hills are developed in the alternating dolomite, gypsum/anhydrite, and shale beds of the Permian Blaine Formation. Ranging from natural bridges to extensive cave systems, the largest is the 10 km of passages in Jester Cave in the Mangum Gypsum Hills. Cave passages formed in the normally paired gypsum and dolomite beds exhibit narrow (1.5-5 in wide), sinuous, canyon-like profiles. The development of broader passages, with widths from 5 in to more than 3 5 in, involve the shale beds. Some are bedding-plane passages with extremely low ceilings, whereas others are comfortable, walking-height passages with ceilings from 3-15 in high. The Blaine Formation, in the area of humanly mappable cave development, is from 12 in to approximately 50 in thick. The caves drain the bluffs/escarpments and normally end in karst spring resurgences. Roof collapse often modifies these resurgences into breakdown mazes. The Weatherford Gypsum Hills caves are formed in the Permian Cloud Chief Formation. The Cloud Chief gypsum is chalkier than the Blaine gypsums and the resultant cave development is more segmented, ranging from natural bridges (1.5-15 in in length) to cave segments (locally referred to as 'tunnels') that are tens of meters to more than one kilometer in length. These caves exhibit very little vertical development, and none of the bedding-plane development found in the Blaine Formation
ENGLACIAL CAVES OBSERVED BY SPELEOLOGISTS - The speleological investigation of moulins, intraglacial conduits and subglacial tunnels allows to collect informations, which help better to understand the behaviour of the glacier in movement. To find these field data it is necessary at first to conceive how appear and evolve intra- and subglacial cavities. They consist of four types: 1) those opened by meltwater; 2) properly so called crevasses; 3) cavities of volcanic origin; 4) cavities in the lee of bedrock bumps. Directly observable data by the cavers must be always propped up with the time. They concern: 1) the location of cavities and their zone of drainage; 2) the morphology of accessible entrances; 3) the state and the stress of the ice host of cavities; 4) an informed morphometry of investigated voids; 5) level variations and relative age of the trapped waters, and present solid load, the nature and its disposal if necessary. All these data should be represented on plans, profils and cross sections that usually draw up the cavers. Because these documents are easely conveyed and available for consultation by a widened scientific community.
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