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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 pitot tube is a device used to measure flow velocity via pressure differences [16].?

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KarstBase a bibliography database in karst and cave science.

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 magnesium (Keyword) returned 51 results for the whole karstbase:
Showing 1 to 15 of 51
Calcium and Magnesium In Karst Waters, 1965, Douglas, I.

The basic textbooks and reference sources in speleology (Kunsky, 1954; Trombe, 1952 and Warwick, 1962) describe the process of solution of carbonate rocks in terms of the system CaCO3 - H20 - CO2, making little or no reference to the role of MgCO3 in the solution process. The widespread occurrence of dolomitic rocks amongst the older sedimentary formations of Australia, e.g., at Buchan, Victoria, and Camooweal, Queensland, makes some knowledge of the complexity of solution processes in rocks containing dolomite highly desirable for the understanding of the development of caves in this continent. This paper is intended to review the scattered literature on this topic and to describe what is known of the behaviour of the system CaO - Mg0 - CO2 - H20.

Seminar on Karst Denudation - The pH of Calcite solutions with and without Magnesium Carbonate present and the implications concerning rejuvenated aggressiveness, 1972, Picknett R. G.

Some aspects of the Magnesium Problem in Karst Weathering with special reference to the North-east Transvaal, South Africa, 1973, Marker M. E.

A New Development in Solving Problems of Large Scale Speleophotography "Diprotodon Poulter", 1977, Poulter, Norman

A discussion of the special requirements of photography in large caverns is followed by a history of the "Diprotodon" magnesium flare as a lighting source. A new model, Diprotodon poulter is described in detail.

Enhanced calcite solubility in dilute magnesium carbonate solutions, 1978, Picknett R. G. , Stenner R. D.

Determination of Karst Water Aggressiveness By Artificial Saturation: A Comparison of Results Obtained Using Limestone and Reagent Grade Calcium Carbonate, 1981, Dunkerley, D. L.

Trials of the method of estimating the aggressiveness of karst water by artificial saturation (Stenner, 1969) were made on stream and spring waters in limestone country at Buchan, Victoria. Saturation was brought about with both laboratory reagent grade calcium carbonate and also with powdered local limestone. Resulting estimates of the initial degree of saturation varied considerably. The differences amounted to an average 5.6% (maximum 8.0%) in aggressiveness estimated from change in total hardness, 8.8% (maximum 14.0%) using calcium hardness, and 9.4% (maximum 31.0%) using magnesium hardness. Whilst the average difference between the two sets of results are not great, and certainly do not prohibit the use of the original Stenner method, they do serve to indicate that in particular individual cases misleading results can be obtained if local limestone is not used. Possible reasons for the differing behaviour of the two materials is suggested.

Palaeogeographic environment during the desiccation of the Black Sea, 1983, Kojumdgieva Emilia,
During the latest Chersonian (about 10.3 m.y. ago) tectonic movements took place leading to an elevation of the Crimean-Caucasian chain and to an isolation of the Fore-Caucasian part of the Black Sea Basin. This part of the basin had been draining the rivers of the Russian Platform and after the isolation it became desalinized, while the main part of the Black Sea Basin was almost desiccated and evaporites, mainly dolomites, formed in it due to the predominant calcium---magnesium---carbonate composition of the Chersonian Sea waters. These dolomites are found in the drillings of DSDP Leg 42B and are confirmed geophysically.The tectonic movements during the latest Chersonian led to the formation of a series of grabens along which the Mediterranean Sea invaded the north Aegean area and a little later (during the Early Maeotian) the Black Sea

Deposition of Tufa on Ryans and Stockyard Creeks, Chillagoe Karst, North Queensland: The Role of Evaporation, 1987, Dunkerley, D. L.

A spring which feeds Ryans and Stockyard Creeks west of Cillagoe, was examined in order to understand the circumstances producing extensive deposits of tufa in the stream channels. The spring water was found to be of considerable hardness (300 ppm total carbonates) and to emerge only very slightly supersaturated with respect to calcium carbonate, but undersaturated with respect to dolomite. Both saturation levels rose very rapidly during the first 150 m of subaerial flow, as did pH and water temperature. In contrast to the reported behaviour of other limestone springs, carbonate hardness at this site does not decrease monotonically downstream, but rather locally undergoes significant increases. In particular, magnesium hardness at 1 km downstream is more than 4 times its value at the spring. These phenomena are explained in terms of evaporative concentration of the dissolved carbonates and in terms of possible chemical changes associated with the mixture of waters having contrasting characteristics at channel and pool sites along the streams.

Groundwater chemistry and cation budgets of tropical karst outcrops, Peninsular Malaysia, I. Calcium and magnesium, 1989, Crowther J,
The discharge and chemical properties of 217 autogenic groundwaters were monitored over a 1-yr period in the tower karsts of central Selangor and the Kinta Valley, and in the Setul Boundary Range. Because of differences in soil PCO2, calcium concentrations are significantly higher in the Boundary Range (mean, 82.5 mg l-1) than in the tower karst terrain (44.6 mg l-1). Local differences in both source area PCO2 and amounts of secondary deposition underground cause marked intersite variability, particularly in the tower karst. Dilution occurs during flood peaks in certain conduit and cave stream waters. Generally, however, calcium correlates positively with discharge, since the amount of secondary deposition per unit volume of water decreases at higher flows. Magnesium concentrations and Mg:Ca Mg ratios of groundwaters are strongly influenced by bedrock composition, though bedrock heterogeneity and the kinetics and equilibria of carbonate dissolution reactions preclude extremely low or high Mg:Ca Mg values. Net chemical denudation rates range from 56.6 to 70.9 m3km2yr-1.The results are considered in relation to cation fluxes in surface runoff, soil throughflow and nutrient cycling. Preliminary calcium and magnesium budgets show that (1) dissolutional activity is largely confined to the near-surface zone; and (2) the annual uptake of calcium and magnesium by tropical limestone forests is similar in magnitude to the net solute output in groundwaters

Geochemistry of submarine warm springs in the limestone cavern of Grotta Azzurra, Capo Palinuro, Italy: evidence for mixing-zone dolomitisation, 1996, Stuben Doris, Sedwick Peter, Colantoni Paolo,
Subtidal springs in and around the submarine limestone cavern of Grotta Azzurra, at Capo Palinuro, Italy, discharge fluids which are warm (-, Na and Mg2, and enriched in Si, alkalinity, Ca2, Sr2, Mn, NH4, PO43- and H2S, relative to surrounding seawater. The compositions of the warm fluid samples collected in and around the cave define mixing lines which suggest dilution of a single thermal fluid (T >= 23[deg]C) by cool overlying seawater (T= 17-17.6[deg]C). The chemical data suggest that the proposed thermal fluid contains two components, one derived from seawater ( 10%). Excess Si, alkalinity, Ca2, Sr2 and Mn relative to seawater are likely derived from the groundwater component or dissolution/hydrothermal alteration of the host rocks. Magnesium has been removed from the seawater component in exchange for Ca2, due to dolomitisation of the limestone and/or hydrothermal alteration reactions. Saturation-state calculations suggest that the vented fluids are near saturation with respect to calcite and supersaturated with respect to dolomite. This and the presence of dolomite in the host rocks and cave-floor sediments suggest that 'mixing-zone' dolomitisation of the limestones is occurring, perhaps kinetically assisted by elevated temperature and/or bacterial mediation in the reducing subseafloor zone. One possible 'end-member' condition is considered for the thermal fluid -- zero-Mg -- which suggests an end-member temperature of 50.5[deg]C and a fluid composition derived from ~ 38% seawater and ~ 62% groundwater. The heat source for the circulating fluids is uncertain, but may involve warm underlying igneous rocks or heating via the geothermal gradient. A continuous in-situ record of vent-fluid temperature, salinity, pH and O2 concentration collected within the cavern is consistent with our interpretation of the fluid origin, and suggests that tidal forcing affects circulation and venting of the warm fluids

Vadose weathering of sulfides and limestone cave development-Evidence from eastern Australia., 1996, Osborne R. A. L.

Many significant limestone caves in eastern Australia (particularly New South Wales, Tasmania) are associated with sulfide deposits and other ore bodies. These deposits have a variety of origins (hydrothermal, paleokarst, volcaniclastic). The sulfides weather on exposure to oxygen - rich vadose seepage water, lowering the water pH and releasing sulfate and magnesium which can lead to the deposition of gypsum and aragonite speleothems. Removal of weathered ores and ore - bearing paleokarst sediments in the vadose zone is, in places, an important mechanism for the formation of large caverns.

Hydrochemical approach to the alterations of the recharge of a karst aquifer consecutive to a long pumping period: Example taken from Pinchinade graben (Mouans-Sartoux, French Riviera), 1999, Reynaud A. , Guglielmi Y. , Mudry J. , Mangan C. ,
The carbonate aquifer of the Pinchinade graben, which has a well-delimited geometry, involves water,vith well-defined chemical types from calcium sulfate to magnesium bicarbonate. Each ground water type corresponds to a well-delimited area of the aquifer: the magnesium bicarbonate for the Liassic and Rhetian limestone water (with 10 to 30 mg L-1 of sulfate) and calcium sulfate for the water of the relatively impermeable layer of the underlying Keuper (with 300 to 1500 mg L-1 of sulfate). A four-year pumping test,vith a bimonthly to daily monitoring of water chemistry has allowed evaluation of the renewal of the exploitable water reserve. During the four-year period, the survey shows that the average discharge is balanced by natural recharge (2.8 to 105 m(3) y(-1)). A change in the chemical character of the water was observed from Rhetian to Keuper type (from 35 to 167 mg L-1 of sulfate), Such a change indicates a progressive exhaustion of the Rhetian reserves, which are the greater part of the exploitable reserve in the area. The same phenomenon is observed daily depending on the pumped discharge and the season. For pumping rates below 26 m(3) h(-1), the borehole drains the Rehetian inflows to a degree depending on high or low water levels. For pumping rates above 26 m(3) h(-1), whatever the period, the permeable Keuper layers are pumped and sulfate peaks ensue

Petrography, strontium, barium and uranium concentrations, and strontium and uranium isotope ratios in speleothems as palaeoclimatic proxies: Soreq Cave, Israel, 1999, Ayalon A, Barmatthews M, Kaufman A,
The reconstruction of the palaeoclimate of the eastern Mediterranean region for the last 60 ka BP is based on the delta(18)O and delta(13)C variations of speleothems from Soreq Cave, Israel. Climatic conditions during most of the rime interval between 60 and 17 ka BP (the period equivalent to the last glacial) were relatively cold and dry, while they were warmer and wetter from 17 ka BP to the present. At similar to 17 ka BP, there was a major climatic change with a sharp increase in annual rainfall and temperature and a very wet period occurring between 8.5 and 7.0 ka BP. During the colder and drier period, large, detritus-free, preferentially oriented calcite crystals were deposited from slow-moving water. As a result of a sharp change in the hydrological regime at similar to 17 ka BP, fast-moving water started entrainment of the soil and carrying detrital material into the cave, and the calcite crystals deposited became small and anhedral. Coinciding with the petrographic and isotopic changes, a sharp drop occurred in the concentrations of strontium, barium and uranium, and in the ratios Sr-87/Sr-86 and (U-234/U-238)(0), which reached mini mum values during the wettest period. This drop reflects enhanced weathering of the soil dolomite host rock. During colder and drier periods, higher trace-element concentrations and higher isotopic ratios reflect an increase in the contribution of salts derived from exogenic sources (sea spray and aeolian dust), and a reduced contribution of weathering from the host dolomites

Research on the soils of karst areas in Hungary (example from Bükk Mountain), 1999, Zseni Anikó,

The author studied the characteristics of the soil nutrient system in a Hungarian karst area, that is on 8 km2 area of the Bükk plateau. The pH, total carbonate content, total soil-nitrogen content, plant available calcium, potassium, magnesium, and phosphorus contents of 63 soil samples were measured. She was able to compare the nutrient system of the soils which occurred in different ecological conditions. There are differences between the nutrient status of the soils of the beech and pine forest and the open fields. The knowledge of the pH plus the N, P, K, Ca, Mg content of the soils can be important regarding the protection of the environment, the maintenance of the forest and the management of the meadows.

Lechuguilla Cave Pool Chemistry, 1986-1999, 2000, Turin, H. J. , Plummer, M. A.
In May 1986, cavers dug into Lechuguilla Cave, in southeastern New Mexico, USA. Subsequent exploration and research have demonstrated that Lechuguilla is a world-class cave, both in size and in speleological importance. Of particular interest to hydrologists and geochemists are the numerous isolated pools throughout much of the cave. Since 1986, close to 200 water samples have been collected and subjected to over 2000 individual analyses. Results of these analyses are collected and published here for the first time. Dominant cations in the pool waters are calcium and magnesium; dominant anions are bicarbonate and sulfate. These characteristics reflect the limestone/dolomite host bedrock of the cave, modified to varying degrees by the caves massive gypsum deposits, associated with the caves early development. The overall chemistry of the water can be explained by a small number of geochemical processes, starting with evaporation and concentration of local rainfall, and dissolution of soil CO2 and local bedrock. Within the cave, excess CO2 is degassed, leading to precipitation of CaCO3 and increased Mg2+:Ca2+ ratios. In some areas of the cave, infiltrating water encounters and dissolves gypsum, leading to increased CaCO3 precipitation and increased SO42-:HCO3- ratios. In at least one location, massive evaporation has created a magnesium sulfate brine. Geochemical characteristics seem to confirm that the pool located at Lechuguillas current deep point is actually the regional aquifer, suggesting that the caves maximum air-filled depth has been reached.

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