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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. ...

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That capacity, specific is the ratio of well discharge to corresponding discharge [16].?

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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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 confined flow (Keyword) returned 7 results for the whole karstbase:
Geochemistry of Regional Groundwater Flow in the Aladag Karstic Aquifer, Eastern Taurids-Turkey: Effect of Flow Conditions, 1995, Bayari C. Serdar, Kurttas Turker
The geochemistry of regional groundwater flow along the Aladag karstic aquifer indicates a remarkable correlation between the hydraulic and geochemical conditions. The Aladag. karstic aquifer, in between the recharge area and the regional erosion base, comprises unconfined and confined sections. A transition zone along which semi-confined flow conditions dominate also occurs between these sections. The parts of the aquifer in which unconfined and confined flow conditions dominate seem to be analogous of geochemically open and closed systems of carbonate dissolution, respectively. The varition of physical and chemical properties of the karstic effluents implies that although the carbonate dissolution is perpetual along the flow system, dissolution rates decrease where confined flow conditions start to prevail. However, gypsum dissolution along the regional flow path seems to be independent of hydraulic conditions.

Speleogenesis of the great gypsum mazes in the Western Ukraine, 2000, Klimchouk A.
Speleogenesis in the region proceeded mainly under confined hydrogeological conditions. While such development still continues in part of the territory, other parts exhibit entrenched karst settings. Huge relict maze cave systems have been explored here, five of which are currently the longest known gypsum caves in the world. They account for well over half of the total length of gypsum caves that has been explored around the world. This unique concentration of large caves is due to the local coincidence of several factors: confined speleogenetic settings with dispersed upward recharge from a basal aquifer, specific structural prerequisites of artesian speleogenesis (nature and frequency of fissuring), favorable regional evolution (rapid uplift, and fossilization of maze systems), and the presence of an overlying limestone bed and a widespread clayey protective cover (which prevented later infilling and/or destruction of the caves). Maze cave development in the Western Ukraine is not specific to gypsum, but it is quite characteristic of confined flow and transverse speleogenesis in a multi-storey aquifer system, provided proper structural conditions exist. The main advantage of speleogenetic studies in gypsum is that, due to its high solubility and fast dissolution kinetics, morphologic evidence of the flow pattern is well displayed and can be rather easily reconstructed. The great gypsum caves in the Western Ukraine can serve as a model example of the transverse artesian speleogenesis.

ACTIVE HYPOGENE SPELEOGENESIS AND THE GROUNDWATER SYSTEMSAROUND THE EDGES OF ANTICLINAL RIDGES, 2009, Frumkin A.

It has been recently acknowledged that hypogenic caves are common in limestone terranes (e.g. KLIMCHOUK, 2000; AUDRA et al., 2002, 2007; AULER AND SMART, 2003; FORD AND WILLIAMS, 2007), with an extensive review by KLIMCHOUK (2007). Anticlinal ridges provide large recharge areas through which meteoric water may flow into confined zones around the peripheries during their history of uplift and associated denudation. The spatially varying stratal dips may create preferred flow routes within the confined zone and consequently promote hypogene speleogenesis at the most suitable sites for the water to rise again and discharge. Active speleogenetic sites thus may be found around the edges of anticlinal ridges where the potentiometric levels in the con?ned zone are high enough to promote the rising, transverse ?ow. Further away towards the adjoining synclinal basin, impermeable cover may be too thick to allow rising flow. The preferred sites for speleogenesis may migrate away from the anticlinal axis during the uplift process and associated lowering of groundwater levels. The common occurence of relict isolated hypogene caves in the Judean anticlinorium (FRUMKIN AND FISCHHENDLER, 2005) have led to the discovery of similar caves actively forming today. The Yarkon-Taninim regional aquifer is divided into lower and upper sub-aquifers, of which the lower one becomes (partly) con?ned near the anticlinal axis, while the upper sub- aquifer becomes con?ned at the western foothills. Upward flow is evident at the Ayalon Salinity Anomaly (ASA) where the upper sub-aquifer is still uncon?ned, so that rising water has much larger free space to ?ll in comparison with the nearby confined zone (FRUMKIN AND GVIRTZMAN, 2006). Approaching the watertable, the emerging rising flow can easily travel laterally along the highly permeable karstified zone. The rising ASA water is comparable to artesian springs, which discharge in the zone of lowest head of the upper aquifer. In the case of the ASA, however, the upward ?ow does not reach the open land surface but instead disperses laterally near the watertable. It may thus be considered an “underground delta”. The conceptual model consists of four-segment flow route: (1) rainwater recharge through outcrops on the anticlinal ridge; (2) lateral confined flow down to a depth of ~-700 m; (3) pressurized upward flow through discrete sub-vertical conduits; and (4) multidirectional pervasive flow close to the water table, with restricted output in which the rising water mingles with the ‘normal’ water of the upper aquifer. Maze caves fed by vertical conduits are typical for such an “underground delta”, as they disperse the flow laterally in many similar routes. Dense cave formation is observed to be associated with the upward flow of aggressive water. Within the “underground delta” the aggressiveness is consumed over short distances laterally away from the sub-vertical feeders. Such formation of large voids by dissolution far from the recharge zone implies renewed hydrochemical aggressiveness. The spatial location of the ASA is determined by three conditions that allow upward leakage from the deep sub-aquifer: (1) the location of the westernmost unconfined zone of the upper sub-aquifer, and its association with nearby confined regions; (2) the large upward head gradient; (3) spatial heterogeneities in the vertical permeability that are associated with tectonically disturbed zones.


Karst hierarchical flow systems in the Western Cordillera of North America, 2013, Ford, Derek

By definition, karstic flow systems are networks of solutional conduits. Their spatial patterns and hierarchical organisation are strongly affected by differing lithology and geologic structure, and by the location and modes of recharge – unconfined, confined, interformational. For purposes of discussion, this paper will review six examples rang-ing across platform and reefal limestones and dolostones, dolostone breccias, gypsum and salt, in widely differing structural, geomorphic and hydrologic settings: (1) The Carcajou River karst at Lat. 65° N in the Mackenzie Mountains, where leaky permafrost superimposes a frozen ground hierarchy on those due to lithology, structure and topog-raphy: (2) The S Nahanni River karst at Lat. 62° N, with an intrusive-derived local thermal system and lengthy, strike-oriented meteoric flow systems that contribute to an outlet H2S thermal system at the basin topographic low: (3) Castleguard Mountain Karst (Lat. 52° N) in massive Main Ranges structures of the Rocky Mountains, with a complex alpine hierarchy of base-flow and overflow springs: (4) Crowsnest Pass, in steep thrust structures in the Rocky Mountain Front Ranges, where regional strike-oriented flow systems extending between Lats. 49° and 50° N and paired above and below a major aquitard have been disaggregated by glacial cirque incision: (5) The Black Hills geologic dome at Lat. 44° N in South Dakota, USA, with a sequence of hot springs at low points around the perimeter, discharging through sandstones but with some of the world’s most extensive hypogene maze caves formed in a limestone karst barré setting behind them: (6) The Sierra de El Abra, at Lat. 23° N in Mexico, a deep and lengthy (100 km) reef-backreef limestone range being progressively exposed and karstified by stripping of a cover of clastic rocks; the springs are few but amongst the largest known in karst anywhere, located at the northern and southern low extremities along the strike of the reef, plus breaches (windows) in the cover further south.


Karst hierarchical flow systems in the Western Cordillera of North America, 2013, Ford, Derek

EARTH TIDE, A POTENTIAL DRIVER FOR HYPOGENIC FLUID FLOW: OBSERVATIONS FROM A SUBMARINE CAVE IN SW TURKEY, 2014, Bayari C. S. , Ozyurt N. N.

Initiation and development of karstification requires a con­tinuous flushing of pore water in equilibrium with carbon­ate minerals. Under confined flow conditions, the energy required for pore water transport is supplied by external pressure sources in addition to the by earth’s gravity. Earth tides and water loads over the confined flow system are the main sources of ex­ternal pressure that drives the pore water. Earth tides, created by the sum of the horizontal components of tide generation forces of moon and sun, causes expansion and contraction of the crust in horizontal direction. Water load on top of the confined flow system causes vertical loading/unloading and may be in the form of recharge load or ocean loading in the inland and sub-oceanic settings, respectively. Increasing and decreasing tide generating force results in pore water transport in the confined system by means of contraction and expansion, respectively. Since these forces operate in perpendicular directions, pore water flushing by earth tides becomes less effective when water load on top of the confined flow system increases. Temporal variation of fresh­water content in a submarine cave is presented as an example of groundwater discharge driven by earth tides and recharge load.


MODELING SPELEOGENESIS USING COMPUTATIONAL FLUID DYNAMICS: POTENTIAL APPLICATIONS TO HYPOGENE CAVES, 2014, Covington M. , Myre J.

Numerical models of speleogenesis typically simulate flow and dissolution within single fractures or networks of fractures. Such models employ fracture flow and pipe flow equations to determine flow rates and only consider average velocities within each fracture segment. Such approximations make large scale simulations of speleogenesis tractable. However, they do not allow simulation of the formation and evolution of micro- or meso-scale cave passage morphologies. Such morphologies are frequently studied within a field setting and utilized for the interpretation of the speleogenetic processes that formed the cave. One classic example is the formation of scallops in cave streams with turbulent flow. Scallops are used to interpret past flow velocities and directions. However, a recent analysis of the theory of limestone dissolution in turbulent flow conditions suggests a discrepancy between theory and reality concerning the formation of limestone scallops (Covington, in review). Similarly, the only attempt to numerically simulate flute formation in limestone found that the flute forms were not stable (Hammer et al., 2011). Motivated by these puzzles, we are developing a computational fluid dynamics (CFD) framework for the simulation of the evolution of dissolution morphologies.

While this project was initially conceived to better understand dissolution in turbulent flow, the tools being developed are particu­larly well-suited to examine a variety of other questions related to cave morphology on the micro- and meso-scales. There has been significant recent discussion about the interpretation of features that are diagnostic of hypogenic or transverse speleogenesis, such as the morphological suite of rising flow defined by Klimchouk (2007). Other authors have suggested that such forms can be found in a variety of settings where confined flow is not present (Mylroie and Mylroie, 2009; Palmer, 2011). We propose that simulation of such forms using a CFD speleogenesis code will allow a more complete understanding of the connections between process and form, because in such simulations the processes occurring are well-known, well-defined, and also can be adjusted within controlled numeri­cal experiments, where relevant parameters and boundary conditions are systematically varied.

The CFD framework we are developing is based on the Lattice Boltzman method (Chen and Doolen, 1998), which is a popular tech­nique for modeling the mechanics of complex fluids, including fluid mixtures, reactive transport, porous media flow, and complex and evolving domain geometries. With this framework it is straightforward to simulate many of the processes occurring in hypogene settings, including complex fluid flows, dissolution, solute and heat transport, and buoyancy-driven flow. Furthermore, this modeling framework allows these processes to be coupled so that their interactions and feedbacks can be explored. With the suite of capabili­ties provided by this framework, we can begin to numerically simulate the processes occurring in hypogene speleogenesis, including the driving mechanisms and the role of buoyancy-driven flow and its relationship with the morphological suite of rising flow. In the spirit of a workshop, this work is presented as in-progress, in the hopes that it will stimulate discussion on potential applications of the model being developed.


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