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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. ...

Did you know?

That isopiestic line is a contour on a piezometric surface connecting points of equal static level [16].?

Checkout all 2699 terms in the KarstBase Glossary of Karst and Cave Terms


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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 causes (Keyword) returned 126 results for the whole karstbase:
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Quaternary engineering geology, 1991,
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Fookes Pg,
The geological and geomorphological effects on the Earth's surface during the Quaternary have been both extensive and profound. An attempt has been made to simplify and summarize these effects by considering the principal agencies at work during the Quaternary: plate tectonics, rapidly rising sea levels, rapidly falling sea levels, rapidly cooling climates and rapidly warming climates. The resulting series of major glacial and interglacial episodes have had far-reaching consequences for the engineering characteristics of the Earth's surface. In attempting to summarize these major omissions will have been inevitable and errors will have occurred due to compression of the subject and its interpretation in a simplified manner. Table 2 summarizes the approach of the paper in itemising the principal Quaternary events, causes and effects, consequences to landscape and inferences to engineering. Each of the six events has been developed into larger tables and accompanied by some discussion and examples. The principal consequences of the events for engineering have been the production of glacial and periglacial soils,over large areas of the northern and southern hemispheres; changes in the sediment patterns on the coasts, the continental shelves and in river systems; and the development of weathering profiles of very variable type and distribution leading to development of in situ residual soils of many different engineering characteristics. The major shifts in climate associated with these events have led to migration of various surface forms which are now being exposed or covered by the present regime, leading to many active slope processes with potential instability for engineering projects and unexpected distribution of materials. The continuing events of plate tectonics which precedes the Quaternary by a long period of geological time explain the distribution of earthquake systems, growing coastlines and mountains, and the pattern of volcanic areas with their own suites of rock and soil of significance for the engineer. ... This 250-word extract was created in the absence of an abstract

HYDROGEOLOGIC CHARACTERISTICS AND DEFORESTATION OF THE STONE FOREST KARST AQUIFERS OF SOUTH CHINA, 1992,
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Huntoon P. W. ,
Stone forest aquifers comprise an important class of shallow, unconfined karstic aquifers in the south China karst belt. They occur under flat areas such as floors of karst depressions, stream valleys, and karst plains. The frameworks for the aquifers are the undissolved carbonate spires and ribs in epikarst zones developed on carbonate strata. The ground water occurs within clastic sediments which infill the dissolution voids. The aquifers are thin, generally less than 100 meters thick, and are characterized by large lateral permeabilities and small storage. The result is that the aquifers are difficult to manage because recharge during the rainy season moves rapidly out of the aquifers. Water levels fall sharply as the dry season progresses and the ground-water supply falls off accordingly. The magnitude and duration of the seasonal recharge pulse that replenishes the stone forest aquifers have been severely impacted by massive post-1958 deforestation in the south China karst region. Water that was formerly retained beyond the wet season in the forested uplands, later to be released to the stone forest aquifers under the lowland plains, now passes quickly through the system during the wet season. The loss of this seasonal upland storage has resulted in both a reduction in the volume of recharge to the lowland stone forest aquifers and a shortening of the seasonal recharge event. The result is accelerated water-level declines in the stone forest aquifers as the dry season progresses which, in turn, causes premature dewatering of wells and decreased spring discharges. This response is compounded by increased ground-water withdrawals as the people attempt to offset the declining supply. Management of the total water-supply system requires not only tinkering with the aquifer, but massive reforestation efforts to restore dry season water retention in the upland parts of the watersheds

HYDROGEOLOGY OF GRAND CAYMAN, BRITISH-WEST-INDIES - A KARSTIC DOLOSTONE AQUIFER, 1992,
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Ng K. C. , Jones B. , Beswick R. ,
On Grand Cayman, freshwater bodies present in the Bluff Formation are typically small and occur as thin lenses floating on top of dense saline water. Evaluation of the water resource potential of these freshwater lenses is difficult because of their variable hydrological conditions, complex paleohydrogeology and aquifer heterogeneity. Secondary porosity created by preferential dissolution of aragonitic fossil components is common. Open fissures and joints developed under tectonic stress and karst development associated with sea-level fluctuations are, however, the two most important causes of porosity and permeability in the aquifers on Grand Cayman. Fracture and karst porosity control the lens occurrence by: (1) acting as avenues for the intrusion of seawater or upward migration of saline water; (2) acting as recharge focal points; (3) enhancing hydrodynamic dispersion; (4) defining lens geometry; (5) facilitating carbonate dissolution along joints and fissures. A clear understanding of the hydrological and geological conditions is important in developing small lenses in a setting similar to that on Grand Cayman. This pragmatic approach can help identify the optimum location of the well field and avoid areas particularly susceptible to saline water intrusion

LAND SUBSIDENCE, SINKHOLE COLLAPSE SAND EARTH FISSURE OCCURRENCE AND CONTROL IN CHINA, 1994,
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Deng As, Ju Jh,
There are many varieties of geological hazard in China which are widely dispersed. Land subsidence is one such hazard and occurs mainly in the coastal cities of east China. Sinkhole collapses are mainly found near those cities of east and middle China that have karst water and karst water-impregnated ore deposits. Earth fissures also occur in east and middle China. All these geological hazards have a great influence upon the construction of engineering works. Though the causes of the hazards may be different, a major contributor is human economic activity. Therefore, a major countermeasure is to control human economic development

HYDRODYNAMIC CONTROL OF INORGANIC CALCITE PRECIPITATION IN HUANGLONG RAVINE, CHINA - FIELD-MEASUREMENTS AND THEORETICAL PREDICTION OF DEPOSITION RATES, 1995,
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Liu Z. H. , Svensson U. , Dreybrodt W. , Yuan D. X. , Buhmann D. ,
Hydrochemical and hydrodynamical investigations are presented to explain tufa deposition rates along the flow path of the Huanglong Ravine, located in northwestern Sichuan province, China, on an altitude of about 3400 m asl. Due to outgassing of CO2 the mainly spring-fed stream exhibits, along a valley of 3.5 km, calcite precipitation rates up to a few mm/year. We have carried out in situ experiments to measure calcite deposition rates at rimstone dams, inside of pools and in the stream-bed. Simultaneously, the downstream evolution of water chemistry was investigated at nine locations with respect to Ca2 Mg2, Na, Cl-, SO42-, and alkalinity. Temperature, pH, and conductivity were measured in situ, while total hardness, Ca-T, and alkalinity have been determined immediately after sampling, performing standard titration methods. The water turned out to be of an almost pure Ca-Mg-HCO3 type. The degassing of CO2 causes high supersaturation with respect to calcite and due to calcite precipitation the Ca2 concentration decreases from 6 . 10(-3) mole/l upstream down to 2.5 . 10(-3) mole/l at the lower course. Small rectangular shaped tablets of pure marble were mounted under different flow regimes, i.e., at the dam sites with fast water flow as well as inside pools with still water. After the substrate samples had stayed in the water for a period of a few days, the deposition rates were measured by weight increase, up to several tens of milligrams. Although there were no differences in hydrochemistry, deposition rates in fast flowing water were higher by as much as a factor of four compared to still water, indicating a strong influence of hydrodynamics. While upstream rates amounted up to 5 mm/year, lower rates of about 1 mm/year were observed downstream. Inspection of the marble substrate surfaces by EDAX and SEM (scanning electron microscope) revealed authigeneously grown calcite crystals of about 10 mu m. Their shape and habit are indicative of a chemically controlled inorganic origin. By applying a mass transfer model for calcite precipitation taking into account the reaction rates at the surface given by Plummer et al. (1978), slow conversion of CO2 into H and HCO3-, and diffusional mass transport across a diffusion boundary layer, we have calculated the deposition rates from the hydrochemistry of the corresponding locations. The calculated rates agree within a factor of two with the experimental results. Our findings confirm former conclusions with respect to fast flow conditions: reasonable rates of calcite precipitation can be estimated in reducing the PWP-rate calculated from the chemical composition of the water by a factor of about ten, thus correcting for the influence of the diffusion boundary layer

Gypsum karst of the Baltic republics., 1996,
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Narbutas Vytautas, Paukstys Bernardas
The Baltic Republics of Estonia, Latvia and Lithuania have karst areas developed in both carbonate and gypsiferous rocks. In the north, within the Republic of Estonia, Ordovician and Silurian limestones and dolomites crop out, or are covered by glacial Quaternary sediments. To the south, in Latvia and Lithuania, gypsum karst is actively developing in evaporites of Late Devonian (Frasnian) age. Although gypsum and mixed sulphate-carbonate karst only occupy small areas in the Baltic countries, they have important engineering and geo-ecological consequences. Due to the rapid dissolution of gypsum, the evolution of gypsum karst causes not only geological hazards such as subsidence, but it also has a highly adverse effect on groundwater quality. The karst territory of the Baltic states lies along the western side of the area, called the Great Devonian Field that form part of the Russian Plain. Within southern Latvia and northern Lithuania there is an area, exceeding 1000 sq. km, where mature gypsum karst occurs at the land surface and in the subsurface. This karst area is referred to here as the Gypsum Karst Region of the Baltic States. Here the surface karst forms include sinkholes, karst shafts, land subsidence, lakes and dolines. In Lithuania the maximum density of sinkholes is 200 per sq. km; in Latvia they reach 138 units per sq. km. Caves, enlarged dissolution voids and cavities are uncommon in both areas.

Origin of the Danube-Aach system, 1996,
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Hotzl H. ,
The Swabian Alb formed by an Upper Jurassic carbonate sequence is the most extensive karst area of Germany. The western part is crossed by the upper Danube River. It represents an old, mainly Pliocene, drainage system that is now restricted by the young Rhine system. The low base level of the upper Rhine graben causes a strong headward erosion. Since the Upper Pliocene, the Danube has lost more than 90%, of its headwaters. The underground Danube-Aach karst system of the western Alb represents the last capture of the Rhine, leading periodically to a complete loss of water in the upper Danube. The seepage of this water, together with the huge karst catchment area, supplies the strong discharge of the Aach Spring, forming the largest spring of Germany with an average discharge of 8.5 m(3) s(-1)

Elevated and variable values of 13C in speleothems in a British cave system, 1997,
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Baker A, Ito E, Smart Pl, Mcewan Rf,
[delta] 13C isotope variations in speleothems have been investigated for samples from the British Isles, where plants which use the Hatch-Slack or C4 photosynthetic pathway are not present. The range of [delta] 13C expected in speleothem carbonate formed in isotopic equilibrium with soil CO2 derived from the overlying C3 vegetation should thus fall in the range -12 to -6[per mille sign]. Forty-one actively growing speleothem samples from low-discharge sites were analysed from Stump Cross Caverns, Yorkshire, England. Ten percent have [delta] 13C greater than -6%. In addition, a large range of [delta] 13C was observed (-8.06 1.38[per mille sign], a 1 [sigma] variability of 17%), with adjacent samples having [delta] 13C differing by a maximum of 4.74[per mille sign]. Similar findings were obtained from a review of analyses of late Quaternary speleothem samples from the British Isles, with 75% of flowstone samples and 57% of high-flow stalagmite samples exhibiting elevated [delta] 13C. Three possible processes are proposed as possible causes of elevated [delta] 13C in speleothems. Firstly, fractionation may occur between the stalactite and stalagmite due to evaporation or degassing. Secondly, degassing of the groundwaters may have occurred within the aquifer before reaching the cave void, allowing release of some CO2 from the water whilst remaining saturated in calcium. Finally, the elevated [delta] 13C may be due to short water residence times in the soil, such that equilibrium between soil water and soil CO2 is not reached. Evidence presented here demonstrates that any one of these mechanisms may be important in the karst areas of the British Isles. Caution is needed before interpreting the [delta] 13C signal within speleothems in terms of palaeovegetation

Deforestation in the Dominican Republic: a village-level view, 1997,
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Brothers Ts,
Deforestation is still rapid in some parts of the Caribbean, though it has attracted much less attention than deforestation in mainland Latin America. This paper examines the history and causes of the recent rapid deforestation of a lowland karst region of the Dominican Republic in the light of models derived from studies in Central America and the Amazon. Investigation was limited to the vicinity of a single village (Los Limones). Information was drawn from interviews, questionnaires and ground reconnaissance, in addition to archival information and aerial photographs. Deforestation at Los Limones involved many of the same elements seen in mainland deforestation, including construction of access roads, spontaneous agricultural colonization, and pasture conversion, but it followed no single mainland model. Logging, not normally emphasized as a cause of Latin American deforestation, played an important role in opening up the forest to agricultural settlement. Pasture conversion was not a matter of aggregation of large ranches by wealthy absentee landowners, as in the Amazon, but apparently a local response to the economic and ecological advantages of cattle raising. Government actions strongly influenced deforestation, but not via colonization schemes or economic subsidies for cattle ranching; the rhythm of deforestation at Los Limones was tied to the monopolistic practices of the dictatorship of Rafael Trujillo and the social disorganization following his assassination. The national government in fact bears the primary responsibility for deforestation of Los Haitises, a conclusion that contradicts the government's own suggestion that the destruction was largely carried out by poor farmers. Prospects for rehabilitation of the deforested area are gloomy because of the extent of ecological damage and the continued adversarial relationship between the government and the rural population

Groundwater circulation and geochemistry of a karstified bank-marginal fracture system, South Andros Island, Bahamas, 1997,
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Whitaker Fiona F. , Smart Peter L. ,
On the east coast of South Andros Island, Bahamas, a major bank-marginal fracture system characterised by vertically extensive cavern systems (blue holes) is developed sub-parallel to the steep-sided deep-water re-entrant of the Tongue of the Ocean. In addition to providing a discharge route for meteoric, mixed and geochemically evolved saline groundwaters, a strong local circulation occurs along the fracture system. This generates enhanced vertical mixing within voids of the fracture system, evidenced by the increasing mixing zone thickness, and the thinning and increasing salinity of brackish lens waters from north to south along the fracture system. Furthermore, tidally driven pumping of groundwaters occurs between the fracture and adjacent carbonate aquifer affecting a zone up to 200 m either side of the fracture.The resultant mixing of groundwaters of contrasting salinity and within and along the fracture system and with the surrounding aquifer waters, together with bacterial oxidation of organic matter, generates significant potential for locally enhanced diagenesis. Undersaturation with respect to calcite within the fresh (or brackish)-salt water mixing zone is observed in the fracture system and predicted in the adjacent aquifer, while mixing between the brackish fracture lens and surrounding high fresh waters causes dissolution of aragonite but not calcite. The latter gives rise to considerable secondary porosity development, because active tidal pumping ensures continued renewal of dissolutional potential. This is evidenced by calcium and strontium enrichment in the brackish lens which indicates porosity generation by aragonite dissolution at a maximum rate of 0.35% ka-1, up to twice the average estimated for the fresh water lens. In contrast saline groundwaters are depleted in calcium relative to open ocean waters suggesting the formation of calcite cements.The development of a major laterally continuous cavernous fracture zone along the margin of the carbonate platform permits enhanced groundwater flow and mixing which may result in generation of a diagenetic `halo' at a scale larger than that generally recognised around syn-sedimentary fractures in fossil carbonates. This may be characterised by increased secondary porosity where a relative fall in sea-level results in exposure and formation of a meteoric groundwater system, or cementation by `marine' calcite both below this meteoric system, and where the bank surface is flooded by seawater

Causes of land subsidence in the Kingdom of Saudi Arabia, 1997,
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Amin A, Bankher K,
The occurrence of land subsidence in the Kingdom Saudi Arabia is either natural or manmade. Natural land subsidence occurs due to the development of subterranean voids by a solution of host rocks in carbonate and evaporite terrains, over many areas of Saudi Arabia. Man-induced land subsidence is either due to the removal of groundwater in the agricultural areas or to wetting of unstable soils. Therefore, earth fissures and a lowering of the ground surface in unconsolidated sediments took place in alluvial plains and volcanic vent terrains. Unstable soils include Sabkha soils and loess sediments. These types of soils occur in coastal plains, desert areas and volcanic terrains. When this soil is wetted either during agricultural activities, waste disposal or even during a rain storm, subsidence takes place due to either the removal of salts from the Sabkha soil or the rearrangement of soil particles in loess sediments

Dispersion and tailing of tracer plumes in a karstic system (Milandre, JU, Switzerland), 1997,
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Jeannin Py. , Marechal Jc.
A large number of tracing experiments have been carried out in a karstic aquifer in the Swiss Jura. These allow to observe the evolution of a tracer plume along the length of a karst conduit. The method of Sauty was used to make possible the comparison between all the observed breakthrough curves. The flow velocities and the dispersivities obtained are extremely variable. The dispersivities measured at different points along the length of an underground stream in the course of the same tracing experiment increase with distance (scale effect). If the fit of theoretical Sauty curves on the experimental curves works well for rising limbs, this is not always the case for falling limbs: a tailing effect or lag of the experimental curves compared to the theoretical ones is often observed. Micro-tracings have shown that the lag effect is linked more to the karst conduit geometry than to the types of flows (turbulent or laminar). Measurable tailing effect is induced by the presence of a single conduit enlargement (also called pool). Further, the experiments have shown that a succession of enlargements along the length of the underground stream causes a clear increase in the dispersivity and a "homogenisation" of the recovery curve which shows up by the apparent disappearance of the lag effect. These observations show clearly the influence of the heterogeneity of the karst conduit geometry on the breakthrough curves. This effect might be considered when one interprets the shape of the breakthrough curves especially for dispersivity estimation.

Estimating subsurface fissure apertures in karst aquifers from equilibrium activities, 1998,
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Field Ms, Mose Dg,
Rn-222 activities were determined for the karst aquifer underlying Walkersville, Maryland, in an area of ground-water discharge from a single geological unit during the summer and fall seasons, Radon-222 equilibrium activities in karst ground waters can be employed in mass-balance models to estimate microfissure, macrofissure, and conduit aperture dimensions, This approach defines Rn-222 generation and loss in karst aquifers as a function of fissure apertures and the U-238 content of the rock, High Rn-222 activities occur in tight fissures and low Rn-222 activities occur in conduits, In the vadose zone, Rn-222 activities are low as a result of degassing, especially if flow is turbulent and activities are decoupled from the phreatic zone, In the phreatic zone, if recharge to fissures causes a reduction of residence time below that required for equilibrium (approximate to 26 days), Rn-222 activities fall, At springs and in the vadose zone, after a rainfall event, Rn-222 activities increase as waters with long residence and with high Rn-222 activities are expelled from fissure and fracture storage, Field data and selected literature values were used to test the model, Models used to predict median microfissure apertures for this karst aquifer yield aperture estimates ranging from 2.8 mu m to 9.2 mu m. Median macrofissure apertures ranged from 5.53 cm to 5.88 cm, Median conduit apertures ranged from 1.16 m to 1.24 m, Comparison of the models results with published data on karst aquifers and observations at the field site suggest that the predicted apertures are reasonable

Geomorphology of the Tertiary gypsum formations in the Ebro Depression (Spain), 1998,
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Elorza Mg, Santolalla Fg,
This paper reviews the current knowledge of the mainly karstic geomorphological features developed in the evaporitic formations of the Ebro Depression (northern Spain). Special emphasis is given to the recently published and unpublished scientific advances. The gypsum formations, of Tertiary age, have an extensive outcrop area within the Ebro Depression. Here, their morphogenesis is controlled mainly by processes of surface and subsurface dissolution acting on the gypsum. Outstanding landforms in the gypsum terrain include saline lakes developed in flat bottom dolines (saladas). Other characteristic morphologies include karren and gypsum domes, which occur on a decimetre scale. Where the gypsum is covered by Quaternary alluvial deposits the karstification processes are especially intense and cause subsidence phenomena. Karstic subsidence affects stream terraces, mantled pediments and infilled valleys, which in the region are called vales. Dissolution-induced synsedimentary subsidence has produced interesting geological features, which include significant thickening and deformation of the alluvial deposits. In contrast to the rapid removal of gypsum by dissolution, the amount of gypsum removed by erosion is low. Water erosion studies carried out on gypsiferous slopes of the Ebro Depression, indicate that the sediment yield ranges from 0.59 to 7.82 t/ha/year. This low yield results from the high infiltration capacity of the soils. Subsidence caused by gypsum dissolution has important socioeconomic consequences in the Ebro Depression. The active alluvial karstification of the gypsum causes numerous sinkholes that are harmful to linear structures (roads, railway Lines, irrigation channels), buildings and agricultural land. Unforeseen catastrophic subsidence also puts human Lives at risk. The benefits of such terrains include thickened alluvial deposits which act as valuable water reservoirs and which form excellent sources of aggregates. Fluvial valleys in this gypsiferous terrain commonly show an asymmetrical geometry with prominent gypsum scarps at one side. These gypsum scarps are affected by numerous landslides. These slope movements are hazardous, may dam rivers and cause flooding of the alluvial plains. (C) 1998 Elsevier Science B.V. All rights reserved

Processes controlling colloid composition in a fractured and karstic aquifer in eastern Tennessee, USA, 1998,
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Mccarthy J. F. , Shevenell L. ,
Groundwater was sampled from a number of wells along recharge pathways between fractured shale and karstic formations to evaluate the chemical and hydrologic mechanisms controlling the nature and abundance of groundwater colloids. The colloids recovered using low flow rate purging and sampling exhibited a composition and abundance consistent with lithology, flow paths, and effects of hydrology and aqueous chemistry on colloid mobilization and stability. In general, the larger-size colloids and Ca-containing colloids were more abundant in the karstic lithologies, while Na-containing colloids were more important in the shales. The composition of the colloids reflected recharge pathways from the fractured shale and dolomite formations on the ridges into the limestone in the valley floor. The Mg-colloids in the limestone reflect the possible contributions from the dolomite, while the Na, K, and Si reflect possible contributions from the shale, However, it was not possible to use the colloid composition as a signature to demonstrate colloid transport from one lithology to another. Mixing of recharge water from the shale with groundwater within the limestone formation and precipitation/dissolution reactions could account for the colloids present in the limestone without invoking transport of specific shale-derived colloids into the limestone formation. The abundance of colloids in groundwater appears to be controlled by both chemical factors affecting colloid stability, as well as physical factors related to hydrology (storm-driven recharge and water velocities). In general, colloids were more abundant in wells with low ionic strength, such as shallow wells in water table aquifers near sources of recharge at the top of the ridges, Increases in cation concentrations due to dissolution reactions along Bow paths were associated with decreases in colloid abundance. However, in spite of elevated ionic strength, colloid concentrations tended to be unexpectedly high in karstic wells that were completed in cavities or water-bearing fractures. The higher levels of colloids appear to be related to storm-driven changes in chemistry or flow rates that causes resuspension of colloids settled within cavities and fractures. Published by Elsevier Science B.V

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