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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 karst fenster is see karst window.?

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 16 to 30 of 272
IMPACT OF PAST SEDIMENT ECOLOGY ON ROCK FRACTURATION AND DISTRIBUTION OF CURRENT ECOSYSTEMS (JURA, FRANCE), 1991,
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Gaiffe M, Bruckert S,
Differences in the fracture type of limestone rocks have resulted in the formation of several main plant soil ecosystems in the montane and subalpine zones of the Jura (800-1 700 m). The sites were on stable landscape with slope < 5%. Locations were chosen to reflect the variation in physical properties of the bedrock and lithic contact. The rock fractures (densities and size), the shape and size of the fragments and the hydraulic conductivities were described and analyzed to characterize the 3 main bedrocks in the area studied (table 1): 1), lapiaz, ie, large rock fragments separated from each other by wide fractures (figs 1-2), 'broken' rocks traversed by numerous fine fractures (fig 2-3), paving-stones crossed by infrequent narrow fractures (fig 3). The effects of rock fracturing on vegetation (table II) and soil formation were significant in reference to porosity and permeability relationships (figs 6-7). Under similar precipitation, meteoric waters flow through the soil and porosity is relative to fracture systems (figs 4, 5). The weathering of cobbles in the soil profiles and along the lithic contacts maintains different soil solution Ca levels and is an important variable in soil and ecosystem formation (table III). Regarding the regional orogenic phases and the tectonic origin of the fractures, we postulate that the different types of fracturation originated from the different chemical and mineralogic composition of the rocks. Significant differences exist in both the calcite and dolomite content, in the insoluble residue content (table IV) and in the percentage of organic matter of the carbonate-free residues (table V, fig 8). The results indicate that the differences in rock composition arose early at about the period of sedimentation. The origin of the differentiation might be due to the sedimentation conditions and environment (fig 9). It is concluded that the present-day plant soil ecosystems may be related to the marine sediment environments of the Jurassic period (fig 10)

DOUBLE FOURIER-SERIES ANALYSIS OF COCKPIT AND DOLINE KARST NEAR BROWNS TOWN, JAMAICA, 1991,
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Brook Ga, Hanson M,
Double Fourier series models of two doline and two cockpit landscapes in northern Jamaica, each 2 x 2 km in area, explained 92% and 90%, and 73% and 58% of the variance in the topographic data. The ten most significant waves accounted for 74% and 76%, and 61% and 58% of the variance in each model. The greater importance of frequency pairs of longer wavelength in the doline karst models suggests that there are fewer horizontally and vertically persistent bedrock fractures controlling topographic development in the doline areas than in the cockpit terrains-a fact confirmed by fracture-trace mapping. Frequency pair orientations and powers indicate that northwest- and northeast-trending fractures exert a major influence on topographic development in the cockpit terrains and that east-trending fractures are relatively more important in the doline areas. Further studies are needed to determine if Fourier models of the doline, cockpit, and tower karst styles differ in a consistent fashion and to find out to what extent these differences are related to the bedding, fracture, and relief characteristics of the karst bedrock

RADON CONCENTRATIONS IN HOMES IN AN AREA OF DOLOMITE BEDROCK - DOOR COUNTY, WISCONSIN, 1993,
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Hawk K. , Stieglitz R. D. , Norman J. C. ,
A statewide survey by the Wisconsin Department of Health and Social Services with U.S.E.P.A. assistance reported an anomalously high percentage of homes in Door County with radon concentrations in excess of 20 pCi/L. The results were of interest because the county is underlain by marine sedimentary rocks rather than the igneous and metamorphic crystalline types usually associated with elevated radon concentrations. A voluntary population of 55 homes was tested for radon using activated charcoal canisters. This population was also asked to provide questionnaire response data on family, home, and socioeconomic aspects. The data were separated into socioeconomic, energy efficiency, radon access, and karst level categories and statistically analyzed. A subpopulation was selected from the larger population for detailed site investigation, which included additional in-home air testing and, at some sites, water supply analysis and in-ground testing for radon. The field investigations collected information on the geology, soil, topography, and home construction and use. The results of the investigation verified and characterized the radon occurrences iu Door County. The presence or absence of karst features is shown to be statistically significant to radon levels

RILLENKARREN ON GYPSUM IN NOVA-SCOTIA, 1993,
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Stenson R. E. , Ford D. C. ,
Rillenkarren are defined as densely packed, rainfall generated, bedrock channels, forming on slopes. They are usually no more than a few centimetres in width. Their lengths are dependant on the downslope extent of exposed bedrock, Rillenkarren exist in many karst terraines on many types of rock. Rillenkarren on gypsum were measured at four differing sites in Nova Scotia. The results are compared with previous data for naturel rillenkarren on limestones. It was found that gypsum rillenkarren tend to exhibit a smaller mean width that those on limestone. Mean lengths could not be established because rillenkarren elongation on the gypsum was limited by the length of the exposed surface. These conclusions result from the first systematic study of naturally occurring rillenkarren on gypsum and are contrary to the previously speculated dimensions reported by various authors

FORMATION OF REGOLITH-COLLAPSE SINKHOLES IN SOUTHERN ILLINOIS - INTERPRETATION AND IDENTIFICATION OF ASSOCIATED BURIED CAVITIES, 1994,
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Panno S. V. , Wiebel C. P. , Heigold P. C. , Reed P. C. ,
Three regolith-collapse sinkholes formed near the Dongola Unit School and the Pentecostal Church in the southern Illinois village of Dongola (Union County) during the spring of 1993. The sinkholes appeared over a three-month period that coincided with development of a new municipal well. The new well was drilled through clay-rich, valley-fill sediment into karstified limestone bedrock. The piezometric surface of the limestone aquifer is above land surface, indicating the presence of an upward hydraulic gradient in the valley and that the valley fill is acting as a confining unit. Pumping during development of the well lowered the piezometric surface of the limestone aquifer to an elevation below the base of the valley fill. It is hypothesized that drainage of water from the sediments, the resulting loss of hydrostatic pressure and buoyant force in overlying sediments, increased intergranular pressure, and the initiation of groundwater flow toward the well resulted in rapid sediment transport, subsurface erosion, and collapse of the valley-fill sediment. The sinkholes follow an approximately east west alignment, which is consistent with one of the two dominant alignments of passages of nearby joint-controlled caves. A constant electrode-separation resistivity survey of the school playground was conducted to locate areas that might contain incipient sinkholes. The survey revealed a positive resistivity anomaly trending N75E in the southern part of the study area. The anomaly is linear, between 5 and 10 m wide. and its trend either intersects or is immediately adjacent to the three sinkholes. The anomaly is interpreted to be a series of pumping-induced cavities in the valley-fill sediments that formed over a preexisting crevice in the karstified bedrock limestone

Karstification without carbonic acid; bedrock dissolution by gypsum-driven dedolomitization, 1994,
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Bischoff Jl, Julia R, Shanks Wc, Rosenbauer Rj,
Aggressive karstification can take place where dolomite and gypsum are in contact with the same aquifer. Gypsum dissolution drives the precipitation of calcite, thus consuming carbonate ions released by dolomite. Lake Banyoles, in northeastern Spain, is a karst lake supplied by sublacustrine springs, and karstic collapse is occurring in the immediate vicinity of the lake. Lake water is dominated by Mg-Ca and SO 4 -HCO 3 , and is supersaturated with calcite that is actively accumulating in lake sediments. Water chemistry, sulfur isotope composition, local stratigraphy, and mass-balance modeling suggest that the primary karst-forming process at Lake Banyoles is dedolomitization of basement rocks driven by gypsum dissolution. Karstification takes place along the subsurface contact between the gypsiferous Beuda Formation and the dolomitic Perafita Formation. This process is here recognized for the first time to cause karstification on a large scale; this is significant because it proceeds without the addition of soil-generated carbonic acid. Gypsum-driven dedolomitization may be responsible for other karstic systems heretofore attributed to soil-generated carbonic acid

KARSTIFICATION WITHOUT CARBONIC-ACID - BEDROCK DISSOLUTION BY GYPSUM-DRIVEN DEDOLOMITIZATION, 1994,
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Bischoff Jl, Julia R, Shanks Wc, Rosenbauer Rj,
Aggressive karstification can take place where dolomite and gypsum are in contact with the same aquifer. Gypsum dissolution drives the precipitation of calcite, thus consuming carbonate ions released by dolomite. Lake Banyoles, in northeastern Spain, is a karst lake supplied by sublacustrine springs, and karstic collapse is occurring in the immediate vicinity of the lake. Lake water is dominated by Mg-Ca and SO4-HCO3, and is supersaturated with calcite that is actively accumulating in lake sediments. Water chemistry, sulfur isotope composition, local stratigrapy, and mass-balance modeling suggest that the primary karst-forming process at Lake Banyoles is dedolomitization of basement rocks driven by gypsum dissolution. Karstification takes place along the subsurface contact between the gypsiferous Beuda Formation and the dolomitic Perafita Formation. This process is here recognized for the first time to cause karstification on a large scale; this is significant because it proceeds without the addition of soil-generated carbonic acid. Gypsum-driven dedolomitization may be responsible for other karstic systems heretofore attributed to soil-generated carbonic acid

MESSINIAN (LATE MIOCENE) KARST ON GRAND-CAYMAN, BRITISH-WEST-INDIES - AN EXAMPLE OF AN EROSIONAL SEQUENCE BOUNDARY, 1994,
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Jones B. , Hunter I. G. ,
The Cayman Unconformity, which separates the Pedro Castle Formation (Pliocene) from the underlying Cayman Formation (Miocene), is a sequence boundary that developed during the Messinian, when sea level was at a lowstand due to glaciation in the Southern Hemisphere. By the end of the Messinian, Grand Cayman was an atoll-like island that had an elevated peripheral rim that was up to 41 m above the central depression. The Cayman Formation contains paleocaves and paleosinkholes that were linked to the Cayman Unconformity. The topography on the Cayman Unconformity is attributed to erosional processes, because (1) there is no evidence of carbonates that formed by constructional processes (i.e., reefs, dunes) in the elevated peripheral rim, and (2) there is ample evidence of dissolutional features in the Cayman Formation. The topography developed on the interior of Grand Cayman during the Messinian was uneven. A deep, basin-like depression, with its base as much as 50 m below the peripheral rim, formed on the western part of the island. By comparison, the floor of the depression on the eastern part of the island was 20-30 m higher. The difference in the topography, which is a reflection of the amount of bedrock dissolution, suggests that the effective rainfall was highest over the western part of the island. The relief on the Cayman Unconformity and associated structures shows that base level during the Messinian karst development was at least 41 m below present-day sea level. This is also provides an estimate of the Messinian lowstand position because the base level in oceanic karst settings is usually controlled by sea level

Enregistrement des mouvements dun versant par les splothmes de la grotte du chemin du Castelleras (Le Tignet, Alpes-Maritimes, France), 1995,
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Gilli E. , Mangan C. , Delange P. , Larre P. , Evin J.
The study of speleothems in a subcutaneous cave developed between a scree and its bedrock, shows the slope movements. All the speleothem couples (stalactite facing a stalagmite) are displaced. Among the speleothems, a 50cm long thin stalac-tite (soda-straw type) has recorded the movements that have affected the slope. Every slope movement is shown in a speleothem axis variation. Radiocarbon datings help define growth speed and make clear the movement history over a 30,000 years period. This analysis confirms the possibility of using speleothem as verticality gauges to define an area stability.

GEOLOGY AND KARST GEOMORPHOLOGY OF SAN-SALVADOR ISLAND, BAHAMAS, 1995,
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Mylroie J. E. , Carew J. L. ,
The exposed carbonates of the Bahamas consist of late Quaternary limestones that were deposited during glacio-eustatic highstands of sea level. Each highstand event produced transgressive-phase, stillstand-phase, and regressive-phase units. Because of slow platform subsidence, Pleistocene carbonates deposited on highstands prior to the last interglacial (oxygen isotope substage 5e, circa 125,000 years ago) are represented solely by eolianites. The Owl's Hole Formation comprises these eolianites, which are generally fossiliferous pelsparites. The deposits of the last interglacial form the Grotto Beach Formation, and contain a complete sequence of subtidal intertidal and eolian carbonates. These deposits are predominantly oolitic. Holocene deposits are represented by the Rice Bay Formation, which consists of intertidal and eolian pelsparites deposited during the transgressive-phase and stillstand-phase of the current sea-level highstand. The three formations are separated from one another by well-developed terra-rossa paleosols or other erosion surfaces that formed predominantly during intervening sea-level lowstands. The karst landforms of San Salvador consist of karren, depressions, caves, and blue holes. Karren are small-scale dissolutional etchings on exposed and soil-covered bedrock that grade downward into the epikarst, the system of tubes and holes that drain the bedrock surface. Depressions are constructional features, such as swales between eolian ridges, but they have been dissolutionally maintained. Pit caves are vertical voids in the vadose zone that link the epikarst to the water table. Flank margin caves are horizontal voids that formed in the distal margin of a past fresh-water lens; whereas banana holes are horizontal voids that developed at the top of a past fresh-water lens, landward of the lens margin. Lake drains are conduits that connect some flooded depressions to the sea. Blue holes are flooded vertical shafts, of polygenetic origin, that may lead into caves systems at depth. The paleokarst of San Salvador is represented by flank margin caves and banana holes formed in a past fresh-water lens elevated by the last interglacial sea-level highstand, and by epikarst buried under paleosols formed during sea-level lowstands. Both carbonate deposition and its subsequent karstification is controlled by glacio-eustatic sea-level position. On San Salvador, the geographic isolation of the island, its small size, and the rapidity of past sea level changes have placed major constraints on the production of the paleokarst

THE KASKASKIA PALEOKARST OF THE NORTHERN ROCKY-MOUNTAINS AND BLACK-HILLS, NORTHWESTERN USA, 1995,
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Palmer A. N. , Palmer M. V. ,
The Kaskaskia paleokarst, part of the Mississippian-Pennsylvanian unconformity in North America, is typified by sinkholes, fissures, and dissolution caves at and near the top of the Kaskaskia Sequence (Madison Limestone and equivalents) and is covered by basal Absaroka siliciclastics (Chesterian to Morrowan). In the Rocky Mountains and Black Hills of the northwestern U. S. A. it postdates earlier features produced by sulfate-carbonate interactions, including breccias, dissolution voids, bedrock alteration, and mineralization. Both the paleokarst and earlier features have been intersected by post-Laramide caves. Ore deposits, aquifers, and petroleum reservoirs in the region are also concentrated along both the paleokarst horizons and earlier sulfate-related features. Each phase of karst modified and preferentially followed the zones of porosity and structural weakness left by earlier phases, producing an interrelated complex of now-relict features. All should be considered together to explain the present aspect of the paleokarst

CORRELATION OF CONTEMPORARY KARST LANDFORMS WITH PALEOKARST LANDFORMS - THE PROBLEM OF SCALE, 1995,
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White W. B. , White E. L. ,
The signature of karst terrain is a suite of characteristic landforms: caves, closed depressions, deranged surface drainage, and sculptured bedrock surfaces. Identification of karst, in reality, is accomplished by an ill-defined mix of morphological, sedimentological, and bedrock-geology evidence. The purely morphological signature depends on an examination of population statistics and the scaling laws for the various landforms. Caves are fragments of active and paleo conduit drainage systems. The distribution of cave lengths is a power function with a fractional (fractal) exponent. The number of closed depressions of given depth or diameter falls off exponentially with increasing size. Blind valley areas relate to stream length and stream order by power laws. Some features of bedrock sculpturing occur at fu;ed scale. Pinnacle karren, however, appear to be scale invariant over seven orders of magnitude of scale range

LIMESTONE WEATHERING IN EASTERN AUSTRALIA .1. EROSION RATES, 1995,
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Smith D. I. , Greenaway M. A. , Moses C. , Spate A. P. ,
A traversing microerosion meter (MEM) was used to measure the rates of surface weathering of limestones in southeastern Australia. There were two groups of MEM sites installed in 1978/9. The aim of the experimental design for the first type, the 13 sites at Cooleman Plain and Yarrangobilly Caves, was to obtain erosion rates for limestones of similar lithology exposed under comparable climate conditions. The sites were positioned to measure erosion over a range of microsolutional forms and with exposure to differing forms of erosion, i.e. subaerial, subsoil and instream. The second set, at Ginninderra close to Canberra, consists of nine limestone slabs of differing lithology, collected from different locations but exposed under identical climatic conditions. The number of individual measurement points at each MEM site varied from 24 to 68. There were major differences in erosion rates between subaerial bedrock and instream sites at Yarrangobilly and Cooleman Plain, but no evidence of differential erosion across the micro-forms. There were differences in the weathering rate for bedrock sites, due to climatic differences, and between the limestone lithologies exposed at Ginninderra. The average rate of erosion for the subaerial bedrock sites at Cooleman Plain and Yarrangobilly over the 13 years was 0.013 mm a(-1) and at Ginninderra 0.006 mm a(-1). At some of the sites microflora (lichens and mosses) caused problems for field measurement. The weathering processes that contribute to the surface lowering are discussed in the accompanying paper by Moses ef al

BACTERIA, FUNGI AND BIOKARST IN LECHUGUILLA CAVE, CARLSBAD-CAVERNS-NATIONAL-PARK, NEW-MEXICO, 1995,
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Cunningham Ki, Northup De, Pollastro Rm, Wright Wg, Larock Ej,
Lechuguilla Cave is a deep, extensive, gypsum- and sulfur-bearing hypogenic cave in Carlsbad Caverns National Park, New Mexico, most of which (> 90%) lies more than 300 m beneath the entrance. Located in the arid Guadalupe Mountains, Lechuguilla's remarkable state of preservation is partially due to the locally continuous Yates Formation siltstone that has effectively diverted most vadose water away from the cave. Allocthonous organic input to the cave is therefore very limited, but bacterial and fungal colonization is relatively extensive: (1) Aspergillus sp. fungi and unidentified bacteria are associated with iron-, manganese-, and sulfur-rich encrustations on calcitic folia near the suspected water table 466 m below the entrance; (2) 92 species of fungi in 19 genera have been identified throughout the cave in oligotrophic (nutrient-poor) ''soils'' and pools; (3) cave-air condensate contains unidentified microbes; (4) indigenous chemoheterotrophic Seliberius and Caulobacter bacteria are known from remote pool sites; and (5) at least four genera of heterotrophic bacteria with population densities near 5 x 10(5) colony-forming units (CFU) per gram are present in ceiling-bound deposits of supposedly abiogenic condensation-corrosion residues. Various lines of evidence suggest that autotrophic bacteria are present in the ceiling-bound residues and could act as primary producers in a unique subterranean microbial food chain. The suspected autotrophic bacteria are probably chemolithoautotrophic (CLA), utilizing trace iron, manganese, or sulfur in the limestone and dolomitic bedrock to mechanically (and possibly biochemically) erode the substrate to produce residual floor deposits. Because other major sources of organic matter have not been detected, we suggest that these CLA bacteria are providing requisite organic matter to the known heterotrophic bacteria and fungi in the residues. The cavewide bacterial and fungal distribution, the large volumes of corrosion residues, and the presence of ancient bacterial filaments in unusual calcite speleothems (biothems) attest to the apparent longevity of microbial occupation in this cave

INFILTRATION MECHANISMS RELATED TO AGRICULTURAL WASTE TRANSPORT THROUGH THE SOIL MANTLE TO KARST AQUIFERS OF SOUTHERN INDIANA, USA, 1995,
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Iqbal M. Z. , Krothe N. C. ,
A hydrogeological study was conducted, during the 1991-1992 water year, in the clay-soil mantled portion of a limestone terrain in southern Indiana. The purpose of the study was to investigate the modes of soil-water infiltration contributing to rapid transport of nitrate to the saturated zone. The I-year-cycle profiles of nitrate concentration vs. time show a consistent increase of nitrate at various depths in the unsaturated zone during the period of investigation. The increase of nitrate in soil water is attributed to the rapid flushing of the inorganic fertilizers from the fields after the area received sufficient rainfall in late fall. The investigation also showed a major movement of nitrate in quick pulses through the unsaturated zone, rather than a slow uniform recharge, immediately after a major storm event. The asymmetric profiles of nitrate concentration vs. depth point to the existence of preferential flow through macropores in the clay-soil mantle above the bedrock. Soil-water transport between storm events is by matrix type flow. Nitrogen isotopes were analyzed for representative groundwater samples collected before and immediately after fertilization of fields in the summer, 1991. The delta(15)N values of the samples did not show any major shift in nitrate sources between the sampling periods. The summer of 1991 was extremely dry prohibiting vertical transport of nitrate from the fields to the groundwater system. Any change in nitrate concentration in groundwater during this time is attributed to the mixing through lateral flow within the aquifer

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