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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 infiltrability is the ease of infiltration [16].?

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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;
See all featured articles from other geoscience journals

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Your search for trenching (Keyword) returned 5 results for the whole karstbase:
Le gouffre Jean-Bernard (1602 m, Haute-Savoie), coulements souterrains et formation du rseau, 1993, Lips B. , Gresse A. , Delamette M. , Maire R.
With its depth of 1602m and development of more than 20 km, the Jean-Bernard system provides a clear view of an alpine karst system with a steep gradient and reduced watershed (4 km2). Over the last 30 years, hundreds of explorations led by the caving club Vulcain (Lyon) have resulted in a thorough knowledge of the cave. The system develops in a syncline formed from urgonian limestone (Lower Cretaceous). Two parts may be distinguished: a complex upper part with numerous dry phreatic tubes, and a lower part, which is restricted to a high meander. A tracing carried out in 1992 has allowed us to locate the outlet in the riverbed of the Clvieux creek (alt. 780m). The former spring of the upper part must have been situated on the level of the lower entrance (about 1800m) and could date back to the end of the Tertiary when the valley was less deep. The quaternary period is responsible of the entrenching of the old galleries, for the destruction of speleothems and the genesis of the lower underground delta, between -1400m and -1600m.

Locating dissolution features in the Chalk, 2000, Matthews M. C. , Clayton C. R. I. , Rigbyjones J. ,
Dissolution features are common in the Chalk and may result in differential or collapse settlement of foundations if undetected. Dissolution pipes and cavities may be easily missed by conventional drilling methods. Probing and geophysical methods of investigation offer an attractive alternative due to their ability to cover large areas rapidly and thus minimize cost. The success of geophysical methods depends on many factors, principally the size of the feature in relation to the depth of burial and the cover material. This paper describes a study of dynamic probing and a number of geophysical methods used to locate dissolution features at two sites with contrasting ground conditions. The first site contained a bowl-shaped doline over a clay-filled dissolution pipe beneath a relatively thin soil cover. At the second site there was a thick, predominantly granular cover material that contained cavities which had migrated from dissolution pipes in the chalk below. Ground truth data from trenching was obtained to provide a basis for evaluating the investigation methods used. The ability of both dynamic probing and geophysical methods to locate and map dissolution features is discussed

Tabor above Zagorje ilentabor, archaeological rescue sample trenching in the area of the castle complex, 2005, Bratina, P.

The valleys of the Pivka and Reka rivers make a natural passage from the upper Posavje to the Trieste and Quarnero Bays. The strategic significance of this area in prehistoric times is shown in the numerous hillforts/settlements on the secured peaks of the hills in Late Antiquity with Roman defence blockades, and in the times of Turkish invasions with forts against the Turks. Rescue sample trenching in 1996 in the area of the Tabor archaeological monument above Zagorje - Šilentabor, archaeological site reference EŠD: 764, revealed part of the remains of a Middle Age defence architectural structure and numerous archaeological artifacts, which confirm construction and life within the castle complex from the 15th to 17th centuries, as mentioned in historical sources.


Active Erosion of Flat Interfluve Summits Above the Multi-storey Artesian Ozark Aquifer , 2010, Elfrink, N. M.

Migrating regional ground water divides can create unstable zones of relatively stagnant flow in upland areas. Unlike traditional upland ground water divides, the process of flow reversal causes these zones to reject recharge. Artesian pressure surfaces limit the downward infiltration of precipitation and form the subenvelope above which ground water sapping can create a ‘peneplain’ (Stearns, 1967). Only regolith and rock above the pressure surface subenvelope is available for epigenic erosion. Inertia is eventually overcome and ground water circulation substantially increases as hydraulically-advantaged, ‘entrenched’ river systems capture the isolated packets of stagnant ground water. As artesian pressure is lost in the upper story, losing streams form. The losing streams may eventually be consumed by the steep slopes of an entrenching stream, thus completing the reversal of flow. Water level data suggest that the dewatering of stagnant divide areas can be hastened by distant earthquakes.

A variety of observations in Missouri, including recent studies using heat pulse flow meters, show that pressurized sandstone aquifers are widespread beneath upland divides and at surprisingly high elevations. The ground water in the sandstones is confined by relatively tight carbonates. Ground water leaves these confined aquifers by slowly percolating upward through the confining carbonate into shallow bedrock fractures. Storm events then flush shallow mineral-laden ground water into surface streams, which is why floodwaters tend to be dominated by ground water (Frederickson & Criss, 1999). In the major valleys, transverse speleogenesis reverses the hydraulic role of the carbonate beds (Klimchouk, 2003). Classic artesian hydrology generally ignores these mechanisms and cannot explain why most large Ozark caves are associated with sandstones. Unlike classic artesian systems, artesian aquifers in the Ozarks typically lack a marginal recharge zone. Artesian pressures are maintained by ongoing vertical movements. A subsidence rate of approximately 1 mm/yr in the Northern Mississippi Embayment (Calais, 2008) would cause the Ozark ground water divide to migrate to the north and west at approximately 0.7 meter per year, assuming a constant gradient. Flat interfluve summits form as the flow reversal process unfolds.

Once thought to be remnants of ancient peneplains formed near sea-level, isotopic evidence now indicates that modern Ozark summits are actually being sapped by relatively shallow but significant zones of chemical migration. The flat summit surfaces and the steep stream valleys form simultaneously as the landscape is lowered and drainages are rearranged. There is no need to postulate the prior existence of a low elevation peneplain. The uppermost artesian pressure surface acts as the base level, not sea level. Flat interfluve surfaces can form at any elevation, depending on hydrologic conditions. The summit surfaces appear flat because they are essentially created by a regional ground water surface that is widespread and relatively flat.


Integrating geomorphological mapping, trenching, InSAR and GPR for the identification and characterization of sinkholes: A review and application in the mantled evaporite karst of the Ebro Valley (NE Spain), 2011, Gutié, Rrez Francisco, Galve Jorge Pedro, Lucha Pedro, Castañ, Eda Carmen, Bonachea Jaime, Guerrero Jesú, S

This contribution illustrates the advantages of integrating conventional geomorphological methods with InSAR, ground penetrating radar and trenching for sinkhole mapping and characterization in a mantled evaporite karst area, where a significant proportion of the karstic depressions have been obliterated by artificial fills. The main practical aim of the investigation was to elucidate whether buried sinkholes overlap the areas planned for the construction of buildings and services, in order to apply a preventive planning strategy. Old aerial photographs and detailed topographic maps were the most useful sources of information for the identification of sinkholes and helped to obtain information on their chronology, either a minimum age or bracketing dates. The InSAR technique provided subsidence rate values ranging from 4.4 to 17.3 mm/yr consistent with the spatial distribution of the mapped sinkholes. This quantitative deformation data helped corroborating independently the existence of active buried sinkholes and improving the delineation of their limits. The GPR profiles contributed to the precise location of sinkhole edges, provided information on the geometry of buried sinkholes and deformation structures and helped to site trenches and to rule out the existence of sinkholes in particular areas. The main input derived from the trenches includes: (1) Confirming or ruling out anomalies of the GPR profiles attributable to subsidence. (2) Precise location of the edge of some filled sinkholes. (3) Information on subsidence mechanisms recorded by various deformation structures and cumulative subsidence magnitude. (4) Calculating minimum long-term subsidence rates using radiocarbon dates obtained from deformed sinkhole deposits. (5) Unequivocal evidence of active subsidence in areas assigned for the construction of buildings


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