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Enviroscan Ukrainian Institute of Speleology and Karstology


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Community news

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 inception horizon is a part of a rock succession that is particularly susceptible to the effects of the earliest cave forming processes and hence is critical to the origin of most non-tectonic caves. by virtue of physical, lithological or chemical deviation from the predominant carbonate facies within the sequence, it passively or actively favors the localized inception of dissolutional activity [9]. see also inception.?

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 bedrock (Keyword) returned 272 results for the whole karstbase:
Showing 31 to 45 of 272
ORIGIN OF ENDOGENETIC MICRITE IN KARST TERRAINS - A CASE-STUDY FROM THE CAYMAN ISLANDS, 1995,
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Jones B. , Kahle C. F. ,
Cavities in the dolostones of the Cayman Formation (Miocene) on Grand Cayman and Cayman Brac commonly contain spar calcite cements and/or a variety of exogenetic (derived from sources external to the bedrock) and endogenetic (derived from sources in the bedrock) internal sediments. Micrite is a common component in many of these internal sediments. The exogenetic micrite, which is typically laminated and commonly contains fragments of marine biota, originated from the nearby shallow lagoons. The endogenetic micrite formed as a residue from the breakdown of spar calcite crystals by etching, as constructive and destructive envelopes developed around spar calcite crystals, by calcification of microbes, by breakdown of calcified filamentous microbes, and by precipitation from pore waters. Once produced, the endogenetic micrite may be transported from its place of origin by water flowing through the cavities. Endogenetic micrite can become mixed with the exogenetic micrite. Subsequently, it is impossible to recognize the origin of individual particles because the particles in endogenetic micrite are morphologically like the particles in exogenetic micrite. Formation of endogenetic micrite is controlled by numerous extrinsic and intrinsic parameters. In the Cayman Formation, for example, most endogenetic micrite is produced by etching of meteoric calcite crystals that formed as a cement in the cavities or by microbial calcification. As a result, the distribution of the endogenetic micrite is ultimately controlled by the distribution of the calcite cement and/or the microbes-factors controlled by numerous other extrinsic variables. Irrespective of the factors involved in its formation, it is apparent that endogenetic micrite can be produced by a variety of processes that are operating in the confines of cavities in karst terrains

Solutional landforms in quartz sandstones of the Sydney Basin, PhD thesis, 1995,
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Wray, R. A. L

Solutional landforms have been described for over a hundred years from limestone terrains and are termed karst. In many tropical regions landforms of similar morphology but on highly siliceous sandstones and quartzites have also recently been identified. The similarity of many of these features in morphology and also in genetic solutional processes to those on limestone has prompted recent calls for these quartzose landforms to also be regarded as true karst.
Although not unknown in temperate latitudes, these highly siliceous solutional landforms have been most commonly studied in present-day tropical regions, or areas believed to have been tropical in the recent past. This concentration of research in hot-wet areas, allied with the long held assertion of the insolubility of silica, especially quartz, led to a belief that tropical climatic conditions are necessary for karstic solution of these rocks. However, some of these quartzose solutional landforms are known in areas of temperate climate where there is little evidence for prior tropical conditions. A comprehensive worldwide review of these landforms, and the processes involved in their formation, has not previously been conducted and forms the basis from which this study stems.
The Sydney Basin in southeastern Australia has had a stable temperate climate for much of the Cainozoic with no evidence of tropical climate. The highly quartzose Permo-Triassic sandstones of this area have little carbonate, but nevertheless display a wide range of landforms morphologically similar to those both on limestones and also tropical quartzites These include large bedrock towers, grikes, caves, smaller solution basins and runnels, and even widespread silica speleothems. This study describes the morphology of this suite of landforms in detail, and provides a comparative analysis of these sandstone forms to those reported from quartzites of tropical areas and also their limestone analogues. Various microscopic and natural water chemistry analysis are then utilised in examining the poorly understood natural processes responsible for their formation. The process of sandstone solutional weathering in the Sydney Basin is also compared with that reported from the tropics, finding very little difference in either the form or magnitude of attack between these two climatically distinct regions. No previous studies have examined the wide range of solutional features found on quartz sandstones in one region of a climate comparable to Sydney, nor the processes involved in the genesis of these forms.


Karst Geomorphology and Hydrogeology of the Northeastern Mackenzie Mountains, District of Mackenzie, N.W.T., PhD Thesis, 1995,
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Hamilton, James P.

This thesis describes the geomorphology and hydrogeology of karst systems in portions of the northeastern Canyon Ranges of the Mackenzie Mountains and the Norman Range of the Franklin Mountains. N.W.T. In the region, mean annual temperatures are -6 to -8°C, total annual precipitation is 325 to 500 mm, and permafrost has a widespread to continuous distribution. The area was glaciated in the Late Wisconsinan by the Laurentide Ice Sheet.
The Canyon Ranges and Norman Range are composed of a sequence of faulted and folded miogeoclinal sedimentary rocks that span the Proterozoic to Eocene. The geology is reviewed with an emphasis on strata that display karst. Included are several dolomite and limestone formations, two of which are interbedded with evaporites in the subsurface. The principal groundwater aquifer is the Lower Devonian Bear Rock Formation. In subcrop, the Bear Rock Formation is dolomite and anhydrite, outcrops are massive calcareous solution breccias. This is the primary karst rock.
The regional distribution and range of karst landforms and drainage systems are described. Detailed mapping is presented from four field sites. These data were collected from aerial photography and ground surveys. The karst has examples of pavement, single and compound dolines, subsidence troughs, polje, sinking streams and lakes. and spring deposits. The main types of depressions are subsidence and collapse dolines. Doline density is highest on the Bear Rock Formation. Surficial karst is absent of less frequent in the zone of continuous permafrost or outside the glacial limit.
At the field sites, water samples were collected at recharge and discharge locations. Samples were analyzed for a full range of ionic constituents and many for natural isotopes. In addition, several springs were monitored continuously for discharge, temperature, and conductivity. Dye tracing established linkages between recharge and discharge at some sites. These data are summarized for each site, as is the role of permafrost in site hydrology.
The relationships between geological structure, topography, ,and groundwater systems are described. Conduit aquifers are present in both dolomite and limestone. These systems are characterized by discharge waters of low hardness and dissolved ion content. Aquifers in the Bear Rock Formation have a fixed flow regime and often have highly mineralized discharge. At the principal field site. there was a time lag of 40 to 60 days between infiltration and discharge in this unit. At a second site, flow through times were on the order of years. Variability in these systems is attributed to bedrock properties and boundary conditions.
Preliminary rates of denudation are calculated from the available hydrochemical data. Total solutional denudation at the primary field site is approximately 45 m³ kmˉ² aˉ¹ (mm kaˉ¹). The majority is attributed to the subsurface dissolution of halite and anhydrite. The predominance of subsurface dissolution is linked to the high frequency of collapse and subsidence dolines and depressions.
The karst features and drainage systems of the northern Mackenzie Mountains date to the Tertiary. Glaciation has had a stimulative effect on karst development through the subglacial degradation of permafrost and the altering of boundary conditions by canyon incision.


Thesis Abstract: Bedrock Caves and fractured rock surfaces in Sweden; Occurrence and origin, 1996,
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Sjoberg R.

Generation of Cave Aerosols by Alpha Particles: Critical Evaluation of the Hypothesis, 1997,
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Pashenko, S. E. , Dublyansky, Y. V.
The paper evaluates the feasibility of the hypothetical mechanism of cave aerosols generation under the action of natural radioactivity. Analysis has been performed from the standpoints of nuclear physics and aerosol mechanics. The hypothetical mechanism involves dislodgment of atoms and ions and knocking-out of larger fragments due to the bombardment of the bedrock by alpha-particles residing in the cave air. Calculations show that the largest amount of atoms and ions that could be generated by alpha-bombardment does not exceed 0.1 g from 1000 m2 of the cave surface per 1 million years a quite negligible value. Presence of any water film thicker than 0.1 micron on the cave wall would completely prevent the dislodgment. The hypothetical mechanism, though physically plausible, cannot play any essential role in the generation of cave aerosols, and much less in the formation of speleothems.

Aufeis of the Firth River basin, Northern Yukon Canada: Insights into permafrost hydrogeology and Karst, 1997,
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Clark Id, Lauriol B,
The 31-km(2) aufeis ice sheet of the upper Firth River holds a wealth of information on groundwater hydrology in periglacial environments. Baseflow recession calculations, corrected for aufeis storage (12% of basin discharge), indicate specific groundwater recharge rates of up to 100 mm yr(-1) (up to 50% of runoff), suggesting a significant proportion of drainage from karst. The upper Firth River aufeis is a composite aufeis, with discrete baseflow contributions from different watersheds. Since the late Pleistocene, annual growth of the aufeis has exerted a strong control on lateral erosion and the local river channel geomorphology. Two groundwater recharge processes are distinguished on the basis of carbonate geochemistry and 8(13)C: (1) Methanogenic groundwaters, with C-13(DIC) up to -3.3 parts per thousand, are recharged through saturated soils underlain by permafrost; conditions which support anaerobic consumption of dissolved organic carbon (DOC) and produce up to 700 mu g-CH4 L-1 (calculated), and (2) Karst groundwaters, with C-13-depleted DIC, recharged through unsaturated soils and circulate through fissured talik in the carbonate bedrock. Most drainage from the region shows varying contributions of these two groundwaters, although a greater contribution from the methanogenic groundwaters occurs in north-facing watersheds. The 8(13)C values far cryogenic calcite precipitates in the ice indicate that the karst groundwaters are the major contribution to aufeis growth. The combined use of 8(13)C(DIC) and geochemistry may be a useful tool to quantify methanogenesis in northern watersheds

Geochemistry and water dynamics: Application to short time-scale flood phenomena in a small Mediterranean catchment .1. Alkalis, alkali-earths and Sr isotopes, 1997,
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Benothman D, Luck Jm, Tournoud Mg,
We report major, trace elements and Sr isotope data for water samples taken regularly during a four-day-long September flood of a Mediterranean river, the Vene (Herault, S. France). The objective is to combine all these data into a dynamic model that describes the origin(s) and movements of waters and their loads. This river drains the runoff from a small, mainly carbonate, partly karstified watershed with Miocene and Jurassic lithologies. The watershed is also impacted by both agricultural and urban activities. Both the dissolved and the particulate loads were analyzed. Concentrations of the dissolved components show major remobilization of almost all elements during the first few hours of the flood (water treatment plants and aerosol scavenging), followed by a sharp concentration decrease. Some major species return to their previous summer values (Ca, HCO3) while others reach low 'background' levels (Na, K, Cl, SO4). Some trace elements (Rb, Sr, Cs) show similar behaviour but (Ba) appears somewhat unaffected. Trace element concentrations and ratios define two main periods (three in the suspended particulate matter). Ratios do not allow distinguishing between the three main sources for the dissolved load in the first period (Miocene, Jurassic, water treatment plants), but clearly show the Jurassic karst influence later on. The Sr-87/Sr-86 Of the suspended particulate matter is more variable and more radiogenic than in the dissolved phase. Variations in concentration ratios and Sr isotope composition in particulates indicate the large and variable contribution of Miocene silicates with some carbonate. However, there is a need for another component with [Rb]/[Sr] higher than bedrocks, internal or external to the watershed, possibly due to differential erosion. Dissolved Ca and Mg fluxes during the flood were calculated at 0.26 ton and 0.029 ton/km(2), respectively. Even though the carbonate nature of the watershed restricts variability in Sr isotope composition in the dissolved load, we distinguish several endmembers: seawater(approximate to marine rain), Miocene marls, Jurassic limestones, water treatment plants (and possibly another attributable to fertilizers). Combined with major and trace element variational Sr isotope fluctuations indicate time-varying proportions of different water endmembers at the outflow and suggest a general dynamic model. Based on PCA (principal component analysis), a 3D representation allows to visualize the geochemical evolution of the Vene waters. In particular, Sr isotopes clearly indicate that the inflow of karstic waters during the flood was not continuous but occurred as a series of marked oscillations between flowing waters with chemical signature of Miocene lithologies and increasing flushes of deeper waters that interacted with Jurassic lithologies. (C) 1997 Elsevier Science B.V

Ce-anomalies in the textural components of upper Cretaceous karst bauxites from the Apulian carbonate platform (southern Italy), 1997,
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Mongelli G. ,
The chemical and mineralogical composition of Upper Cretaceous Apulian karat bauxites (southern Italy) and their textural components, i.e. ooids and matrix, has been studied. The bulk samples are composed of boehmite, hematite, anatase and kaolinite. The samples collected along a vertical profile show a downward enrichment for the elements Rb, Sr, Ba, Ni and Cr. A similar distribution is observed in deposits bauxitized in situ at the expense of matrix-like material collected in the karst zone. The ooids consist mainly of hematite with minor boehmite and anatase, whereas in the matrix boehmite prevails on hematite, kaolinite and anatase. In the void fillings in the matrix there is a Ca-fluorocarbonate having a Ce/Ce* of 5.8. The ooids, with the exception of Ce, are enriched in REE and show a higher (La/Yb)(ch) ratio relative to the matrix. The matrix exhibits a large positive Ce-anomaly whereas the ooids have negative Ce-anomaly. The Ce fractionation between the textural components can be explained assuming: (1) Ce oxidation and cerianite precipitation in the uppermost part of the deposits; (2) scavenging of REE from Ce-depleted percolating solutions by the iron oxide, inducing both REE-enrichment and Ce-negative anomalies in ooids; (3) remobilization of cerium as fluoride complex, as a consequence of more acidic conditions in the uppermost part of the deposit, and precipitation of Ce3 as fluorocarbonate mineral toward the carbonate bedrock barrier, at alkaline pH. Alternatively, the cerium remobilization, possibly as a carbonate-fluoride complex, could be due to an Eh decrease, favoured by a rise of the groundwater level. (C) 1997 Elsevier Science B.V

A global review of solutional weathering forms on quartz sandstones, 1997,
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Wray R. A. L. ,
Solutional landforms in limestone have been described for over a hundred years, but landforms of similar morphology on highly siliceous sandstones and quartzites have also been identified in a wide variety of environments and generally termed pseudokarst. These include large bedrock pinnacles and towers, caves, corridors, grikes, solution basins and runnels, and even silica speleothems. Quartzites and quartz sandstones have been held to be amongst the most chemically resistant of rocks, but the similarity, both in morphology and genetic process of many landforms developed from them to features of known solutional origin on limestone, has prompted some authors to refer to these quartzose landforms as true karst.The most detailed studies of quartzose karst landforms have been in present-day tropical regions, or areas believed to have been tropical in the geologically recent past. This concentration of research in hot-wet areas, allied with the long held assertion of the insolubility of silica, especially quartz, has led to a belief that tropical climatic conditions are necessary for karstic solution of these rocks. However, the existence of quartzose karst landforms in temperate and even sub-polar latitudes, especially where there is no evidence of prior tropical conditions, suggests that the requirement of tropical weathering is no longer tenable.The reports of these quartzose solutional landforms are widely scattered through the geomorphological and geological literature, but a comprehensive world-wide review of the range of solutional landforms on quartzose rocks has not previously been published. Because of the increasing awareness in this karst type such a summary is sorely overdue

Strategic ground water management for the reduction of karst land collapse hazard in Tangshan, China, 1997,
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Wang H. T. , Li Y. X. , Wang E. Z. , Zhao Z. Z. ,
Karst land collapse is a geological hazard caused mainly by human activities such as the pumping of ground water. The present study is aimed at determining a management strategy to minimize the risk of karst land collapse in the urban area of Tangshan, China. A method of groundwater management for multi-aquifer systems with groundwater confined and unconfined interchange properties has been developed. A groundwater simulation model and a management model are constructed for the studied area. The data used by the simulation and management models include the geometry of the aquifer systems, the parameters of hydrogeology, the distribution of recharge, and discharge in the simulation period and the historical water table elevations. The results of the model calculations show that the total balance between recharge and discharge for both Quaternary and bedrock aquifers is 4.7 x 106 m(3) in the period from November 1989 to October 1990. The optimal annual average pumping rate from the underlying bedrock aquifer is some 25.8 x 10(6) m(3), which is 54.4% of that which was pumped out of the aquifer in the hydrological year of 1990. If the management plan is carried out, the groundwater level in the bedrock aquifer will recover its confined state in most of the areas at risk of land collapse. This is the most resistant state to collapse in terms of groundwater flow.

Sinkholes, soils, fractures, and drainage: Interstate 70 near Frederick, Maryland, 1997,
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Boyer Bw,
Numerous sinkholes have recently formed on both sides of Interstate 70 south of Frederick, Maryland, All the sinkholes are cover-collapse types, which form when soil cavities grow upward from the bedrock surface until their roofs become unstable, Areas at greatest risk for sinkhole development lie within a network of dry swales, The roughly dendritic map pattern and presence of allochthonous siliciclastic alluvium suggest that these swales are the vestiges of a vanished surface drainage system. Sinkholes occur mainly along bedrock escarpments underlying the swales, which are located along an easterly-trending transverse fracture and a series of strike-parallel fractures which intersect with it. Although the surface drainage appears to have Bowed east and north in the past, surface runoff in large quantities is infiltrating the ground or directly entering some of the sinkholes, then following subsurface conduits which convey it southward under the highway. Compaction grouting has been employed to prevent collapse or further subsidence of the most threatened portions of the highway. Soil Survey maps can be useful in locating cryptic intermittent or relict drainage pathways which may be at high risk for sinkhole formation when subjected to anthropogenic concentrations of perched storm water

A pre-Pliocene or Pliocene land surface in County Galway, Ireland, 1997,
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Coxon P, Coxon C,
This paper describes a site on the Carboniferous limestone of County Galway, Ireland, where a complex of gorges, cave passages and shallow surface depressions is filled with organic silt and clay overlain by white quartz sand. The dating of the biogenic deposits to the Late Pliocene by biostratigraphical means provides a record of this largely undocumented period of Irish geological history. However, the particular importance of this site is that unlike other Irish karst infills, it represents not just the localized preservation of material in a closed depression but evidence of a more widespread cover of sediments suggesting the preservation of a Pliocene or pre-Pliocene land surface. This implies that glacial action throughout the Pleistocene has resulted in relatively little bedrock erosion in this region and raises the possibility that the present day landscape of the western Irish limestone lowlands may retain influences of preglacial karstification

Occurrence of selected herbicides and herbicide degradation products in Iowa's ground water, 1995, 1997,
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Kolpin D. W. , Kalkhoff S. J. , Goolsby D. A. , Sneckfahrer D. A. , Thurman E. M. ,
Herbicide compounds were prevalent in ground water across Iowa, being detected in 70% of the 106 municipal wells sampled during the summer of 1995, Herbicide degradation products were three of the four most frequently detected compounds for this study. The degradation product alachlor ethanesulfonic acid was the most frequently detected compound (65.1%), followed by atrazine (40.6%), and the degradation products deethylatrazine (34.9%), and cyanazine amide (19.8%). The corn herbicide acetochlor, first registered for widespread use in the United States in March 1994, was detected in a single water sample, No reported herbicide compound concentrations for this study exceeded current U.S. Environmental Protection Agency's maximum contaminant levels or health advisory levels for drinking water, although the herbicide degradation products examined have get to have such levels established. The occurrence of herbicide compounds had a significant, inverse relation to well depth and a significant, positive relation to dissolved-oxygen concentration. It is felt that both well depth and dissolved oxygen are acting as rough surrogates to ground-water age, with younger ground water being more likely to contain herbicide compounds. The occurrence of herbicide compounds was substantially different among the major aquifer types across Iowa, being detected in 82.5% of the alluvial, 81.8% of the bedrock/ karst region, 40.0% of the glacial-drift, and 25.0% of the bedrock/nonkarst region aquifers. The observed distribution was partially attributed to variations in general ground-water age among these aquifer types. A significant, inverse relation was determined between total herbicide compound concentrations in ground water and the average soil slope within a 2-km radius of sampled wens. Steeper soil slopes may increase the likelihood of surface runoff occurring rather than ground-water infiltration-decreasing the transport of herbicide compounds to ground water. As expected, a significant positive relation was determined between intensity of herbicide use and herbicide concentrations in ground water

Geochemical patterns in soils of the karst region, Croatia, 1997,
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Prohic E. , Hausberger G. , Davis J. C. ,
Soil samples were collected at 420 locations in a 5-km grid pattern in the Istria and Gorski Kotar areas of Croatia, and on the Croatian islands of Cres, Rab and Krk, in order to relate geochemical variation in the soils to underlying differences in geology, bedrock lithology, soil type, environment and natural versus anthropogenic influences. Specific objectives included assessment of possible agricultural and industrial sources of contamination, especially from airborne effluent emitted by a local power plant. The study also tested the adequacy of a fixed-depth soil sampling procedure developed for meager karstic soils. Although 40 geochemical variables were analyzed, only 15 elements and 5 radionuclides are common to all the sample locations. These elements can be divided into three groups: (1) those of mostly anthropogenic origin - Pb, V, Cu and Cr; (2) those of mixed origin - radionuclides and Zn; and (3) those of mostly geogene origin - Ba, Sr, Ti, Al, Na, Ca, Mg, Fe, Mn, Ni and Co. Variation in Pb shows a strong correlation with the pattern of road traffic in Istria. The distributions of Ca, Na and Mg in the flysch basins of southern Istria and Slovenia are clearly distinguishable from the distributions of these elements in the surrounding carbonate terrains, a consequence of differences in bedrock permeability, type of drainage and pH. The spatial pattern of Cs-137 from the Chernobyl nuclear power plant accident reflects almost exclusively the precipitation in Istria during the days immediately after the explosion. (C) 1997 Elsevier Science B.V

Strategy for evaluating channeling in the carbonate bedrock at Smithville, Ontario, 1997,
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Worthington S. R. H. , Ford D. C.

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