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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 water-bearing is containing water [16].?

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
See all featured articles
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;
See all featured articles from other geoscience journals

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Your search for folds (Keyword) returned 26 results for the whole karstbase:
Showing 16 to 26 of 26
Tectonic subsidence v. erosional lowering in a controversial intramontane depression: the Jiloca basin (Iberian Chain, Spain), 2007, Rubio Jose C. , Simon Jose L. ,
The Jiloca basin is a large intramontane, NNW-SSE-trending topographical depression in which the relative role of tectonic subsidence and erosional lowering is currently a matter of discussion. Geometry and facies of the sedimentary infill at its central sector have now been characterized from compiled borehole data, which allows discussions of how the evolutionary model is constrained. The central Jiloca depression contains a Late Pliocene to Pleistocene sedimentary sequence made up of alluvial fan, pediment mantle and episodic palustrine deposits, overlying a carbonate unit that could represent an early lacustrine stage of Late Miocene-Early Pliocene age. The geometry of these units is partially controlled by NW-SE-striking normal faults. Both the morphological depression and the sedimentary basin truncate previous folds, whose traces beneath the Neogene-Quaternary infill have been interpreted from the geology of the basin margins, borehole data and hydrogeological criteria. The northern and southern sectors of the Jiloca depression are bounded by faults showing measurable hectometric-scale throws (Calamocha and Concud faults). Moreover, in the central sector, the ~ 350-400 m tectonic uplift of Sierra Palomera has been interpreted from a morphostructural reconstruction of the tilted block which separates the Teruel and Jiloca graben, being similar to the height of the Sierra Palomera mountain front. All these features are consistent with a tectonic basin developed within the framework of the Neogene-Quaternary extensional evolution of eastern Spain. In contrast, they are hardly compatible with genetic models based on erosional deepening, either topographic lowering by numerous nested Tertiary erosion pediplains, or sub-alluvial Pliocene-Quaternary karstic corrosion

Effects of Karst and geological structure on groundwater flow: The case of Yarqon-Taninim Aquifer, Israel, 2010, Dafny Elad, Burg Avi, Gvirtzman Haim

This study demonstrates the significant influences of the geological structure (especially folding and lithology) and the karst system on groundwater flow regime. Folds divert groundwater flow from the general hydraulic gradient; marly layers sustain several perched sub-aquifers above the regional aquifer; and karstification increases the hydraulic conductivity by several orders of magnitude. These phenomena are quantitatively demonstrated within the Yarqon-Taninim (YT) basin, Israel, which is a complex groundwater system, combining several (extremely) opposite characteristics: humid and arid recharge zones, phreatic and confined parts, shallow and deep sub-aquifers, stratified and relatively-homogeneous sub-basins, saline and fresh water bodies, as well as stagnant and fast-flowing groundwater regions.

We have introduced a 3D geological-based grid for the basin (for the first time). It was implemented into a numerical code (FEFLOW), which was used thereafter to analyze quantitatively the flow regime, the groundwater mass balance, and the aquifer hydraulic properties. We present up to date conceptual understanding and numerical modeling of the YT flow field, especially at its mountainous parts.

Based on the calibration procedure and the sensitivity analyses, we obtained the best-fitted hydraulic conductivity values for the aquifer mesh. The general phenomenon observed is that as groundwater flow quantity increases, the hydraulic conductivity also increases. We interpret this result by the karstification mechanism (including paleo-karst). Thus, where groundwater flow-lines converge and where groundwater discharge amount increases, the karstification process intensifies and permeability increases. Consequently, at the mountainous region, along the syncline axes, where groundwater flow-lines converge, higher conductivities are found.

Modeling results also exhibit that at the lowland confined area, the geological structure does not play a major role in directing groundwater flow. Rather, the flow field is controlled by the well-developed karst system and the relatively homogenous carbonate section. It is hypothesizes that the extensive karstification took place at the Messinian Salinity Crises, 5.5 Ma, during which groundwater heads as well as sea level were lowered by several 100 m.

Fold and fault control on the drainage pattern of a double-karst-aquifer system, Winterstaude, Austrian Alps, 2010, Goldscheider N, Neukum C.

Lithostratigraphy and geologic structures are major controls on groundwater flow in alpine karst systems. Understanding these factors is important for the delimitation of drinking water protection zones. The Winterstaude mountain chain, western Austria, belongs to the Helvetic nappes and consists of Cretaceous sedimentary rocks, including two karstifiable formations: rfla and Schrattenkalk Limestone (lower and upper karst aquifer), separated by 60 m of marl. Strata are folded and cut by faults with displacements of 40–70 m. Folded carbonate rocks continue below the alluvial valley floor so that the karst system can be subdivided in shallow and deep phreatic zones. This area is suitable for studying the combined influence of folds and faults on groundwater flow in a double-aquifer system. A multi-tracer test with seven injections aimed at characterising hydraulic connections and linear flow velocities. Results show that (i) plunging synclines form the main drainage pathways in the upper karst aquifer, with maximum linear velocities of 91 m/h, while anticlines act as water divides; (ii) recharge into the lower aquifer, which forms the central ridge of the mountain chain, contributes to springs discharging from the upper aquifer near the foot of the mountain (local flow systems); (iii) the two aquifers are hydraulically connected, presumably via faults, because their displacements are in the same order of magnitude as the thickness of the intervening marl; (iv) flow in the upper aquifer continues below the valley floor toward the river, with maximum velocities of 22 m/h (intermediate flow system).

Active Erosion of Flat Interfluve Summits Above the Multi-storey Artesian Ozark Aquifer , 2010, Elfrink, N. M.

Migrating regional ground water divides can create unstable zones of relatively stagnant flow in upland areas. Unlike traditional upland ground water divides, the process of flow reversal causes these zones to reject recharge. Artesian pressure surfaces limit the downward infiltration of precipitation and form the subenvelope above which ground water sapping can create a ‘peneplain’ (Stearns, 1967). Only regolith and rock above the pressure surface subenvelope is available for epigenic erosion. Inertia is eventually overcome and ground water circulation substantially increases as hydraulically-advantaged, ‘entrenched’ river systems capture the isolated packets of stagnant ground water. As artesian pressure is lost in the upper story, losing streams form. The losing streams may eventually be consumed by the steep slopes of an entrenching stream, thus completing the reversal of flow. Water level data suggest that the dewatering of stagnant divide areas can be hastened by distant earthquakes.

A variety of observations in Missouri, including recent studies using heat pulse flow meters, show that pressurized sandstone aquifers are widespread beneath upland divides and at surprisingly high elevations. The ground water in the sandstones is confined by relatively tight carbonates. Ground water leaves these confined aquifers by slowly percolating upward through the confining carbonate into shallow bedrock fractures. Storm events then flush shallow mineral-laden ground water into surface streams, which is why floodwaters tend to be dominated by ground water (Frederickson & Criss, 1999). In the major valleys, transverse speleogenesis reverses the hydraulic role of the carbonate beds (Klimchouk, 2003). Classic artesian hydrology generally ignores these mechanisms and cannot explain why most large Ozark caves are associated with sandstones. Unlike classic artesian systems, artesian aquifers in the Ozarks typically lack a marginal recharge zone. Artesian pressures are maintained by ongoing vertical movements. A subsidence rate of approximately 1 mm/yr in the Northern Mississippi Embayment (Calais, 2008) would cause the Ozark ground water divide to migrate to the north and west at approximately 0.7 meter per year, assuming a constant gradient. Flat interfluve summits form as the flow reversal process unfolds.

Once thought to be remnants of ancient peneplains formed near sea-level, isotopic evidence now indicates that modern Ozark summits are actually being sapped by relatively shallow but significant zones of chemical migration. The flat summit surfaces and the steep stream valleys form simultaneously as the landscape is lowered and drainages are rearranged. There is no need to postulate the prior existence of a low elevation peneplain. The uppermost artesian pressure surface acts as the base level, not sea level. Flat interfluve surfaces can form at any elevation, depending on hydrologic conditions. The summit surfaces appear flat because they are essentially created by a regional ground water surface that is widespread and relatively flat.

Structural and host rock controls on the distribution, morphology and mineralogy of speleothems in the Castanar Cave (Spain), 2011, Alonsozarza A. M. , Martinperez A. , Martingarcia R. , Gilpena I. , Melendez A. , Martinezflores E. , Hellstrom J. , Munozbarco P.

The Castanar Cave (central western Spain) formed in mixed carbonate-siliciclastic rocks of Neoproterozoic age. The host rock is finely bedded and shows a complex network of folds and fractures, with a prevalent N150E strike. This structure controlled the development and the maze pattern of the cave, as well as its main water routes. The cave formed more than 350 ka ago as the result of both the dissolution of interbedded carbonates and weathering of siliciclastic beds, which also promoted collapse of the overlying host rock. At present it is a totally vadose hypergenic cave, but its initial development could have been phreatic. The cave's speleothems vary widely in their morphology and mineralogy. In general, massive speleothems (stalactites, stalagmites, flowstones, etc.) are associated with the main fractures of the cave and bedding planes. These discontinuities offer a fairly continuous water supply. Other branching, fibrous, mostly aragonite speleothems, commonly occur in the steeper cave walls and were produced by capillary seepage or drip water. Detailed petrographical and isotope analyses indicate that both aragonite and calcite precipitated as primary minerals in the cave waters. Primary calcite precipitated in waters of low magnesium content, whereas aragonite precipitated from magnesium-rich waters. Differences in isotope values for calcite (-5.2‰ for ?18O and -9.6‰ for ?13C) and aragonite (?18O of -4.5‰ and ?13C of -3.5‰ ) can be explained by the fact that the more unstable mineral (aragonite) tends to incorporate the heavier C isotope to stabilize its structure or that aragonite precipitates in heavier waters. Changes in the water supply and the chemistry and instability of aragonite caused: (1) inversion of aragonite to calcite, which led to the transformation of aragonite needles into coarse calcite mosaics, (2) micritization, which appears as films or crusts of powdery, opaque calcite, and (3) dissolution. Dolomite, huntite, magnesite and sepiolite were identified within moonmilk deposits and crusts. Moonmilk occurs as a soft, white powder deposit on different types of speleothems, but mostly on aragonite formations. Huntite and magnesite formed as primary minerals, whereas dolomite arose via the replacement of both huntite and aragonite. Owing to its variety of speleothems and location in an area of scarce karstic features, the Castanar Cave was declared a Natural Monument in 1997 and is presently the target of a protection and research programme. Although the main products formed in the cave and their processes are relatively well known, further radiometric data are needed to better constrain the timing of these processes. For example, it is difficult to understand why some aragonite speleothems around 350 ka old have not yet given way to calcite, which indicates that the environmental setting of the cave is still not fully understood. 

Hypogene Processes of the Gypsum Beds in Sangaw Sinkholes, Kurdistan Region, NE-Iraq, 2011, Ameen, B. M.

The Sangaw region is located at the western part of Zagros orogenic belt at the boundary between Low and High Folded Zones, Sulaimani governorate in Kurdistan region. The area characterized by low amplitude folds that are trending northwest southeast and arranged in en echelon pattern. The exposed formations are Eocene Pila Spi (limestone), middle Miocene Fat`ha(lagoon) and Upper Fars (clastics) formations. Many large and small sinkholes are found around Ashdagh anticline; some of them about 50 m in diameter and about 30 m deep. Some are developed into complicated cave systems with collaps blocks and breccias in addition to narrow passages and fissures. The largest of them is located directly to the west of Darzilla village at the southeastern plunge of Ashdagh anticline. The sinkholes occur in Fat`ha and in the Pila Spi Formations. The walls of the sinkholes are covered by secondary gypsum, sulfur, bitumen and secondary calcite. Inside the cave collapse, breccias and blocks with lensoidal stratified clayey sediments as weathering product could be seen. The water is acidic (pH=4) inside the caves and discharges as large spring (200L/S) with white milky color; it is called in the local Kurdish language, “Awa Spi “which means white stream. The weathering of the carbonate rocks is intense inside the cave and appears as honeycombs and rills mark which have very rough surface with dull color. The sinkholes were produced from the dissolution of thick gypsum and limestone beds. The origin of these caves has been proposed to be hypogenic speleogenesis due to the presence of gypsum and bitumen. These materials with the aid of bacteria enrich the water with H2S which aciditfies the water and precipitates the sulfur and secondary gypsum on the cave wall. The formation of H2SO4 by oxidaton of H2S is the main reason that aid the sinkhole hypogene generation in Sangaw area. A realistic model is drawn to interpret and connect the following: 1- The stratigraphy and structure of the area encourage the generation of underground stagnant pond suitable for reacting with the emanating H2S necessary for the hypogene generation of the sinkholes and precipitation of secondary native sulfur and gypsum.2- dissolution of gypsum and its reduction by bacteria. 3- upward migration of bitumen from nearby oil traps(hydrocarbon accumulation).

Environmental Hydrogeological Study of Louros watershed, Epirus, Greece, 2012, Konstantina Katsanou

The present study aims to describe and characterize the Ionian zone karst formation concerning the karstification grade of carbonate formations and the development of aquifers, through the hydrogeological study of Louros River drainage basin, considering hydrological, hydrogeological and meteorological data, as well as major, trace element, rare earth element and isotope concentrations. It also aims to investigate basic karst properties such as storativity, homogeneity, infiltration coefficients and the parameters of the Louros basin hydrological balance.

To accomplish this aim daily discharge measurements obtained from Public Power Corporation at the Pantanassa station during the years 1956-1957, along with random discharge measurements from 15 springs along the basin performed by IGME between the years 1979-1989, daily meteorological data from 18 stations and 18 sets of potentiometric surface measurements from 38 sites were compiled. Additionally, chemical analyses on major and trace element concentrations of 42 rock samples and of five sets of water samples from 64 sampling sites, along with fourteen sets of successive periods in order to study the seasonal variation in the chemical composition of 11 springs and REE concentrations of 116 water samples. Moreover isotope ratios from 129 rain samples collected at five different altitudes, 331 samples of surface and groundwater samples, radon measurements on 21 groundwater samples and microbiological on 46 samples of surface and groundwater were evaluated. Daily runoff and random spring discharge missing data were completed applying the SAC-SMA and MODKARST simulation algorithms and the values of these parameters for the duration of the research (2008-2010) were predicted. The accuracy of the predicted values was tested applying statistical methods but also against observed values from in situ measurements performed during the same period (2008-2010).

Louros River drainage basin is located at the southern part of Epirus and covers an area of 953 km2. It is elongated and together with the adjacent basin of River Arachthos they constitute the major hydrographic systems discharging in the Amvrakikos Gulf. The main morphological features of the basin are elongated mountain ranges and narrow valleys, which are the result of tectonic and other geological processes mainly controlled by the limestone-“flysch” alternations. The length of the river’s major channel, which is parallel to the major folding direction (NNW-SSE), is 73.5 km. The mountainous part of the hydrogeological basin covers an area of 400 km2 and its endpoint was set at the Pantanassa station, where discharge measurements are performed. The underground limits of the basin coincides with the surface one, defined by the flysch outcrops at the western margin of the Ziros-Zalongo fault zone to the South, the application of isotope determinations and hydraulic load distribution maps at the North and East.

Geologically, Louros River drainage basin is composed of the Ionian zone formations. Triassic evaporites constitute the base of the zone overlain by a thick sequence of carbonate and clastic sedimentary rocks deposited from the Late Triassic to the Upper Eocene. In more detail, from base to top, the lithostratigraphical column of the zone includes dolomite and dolomitic limestone, Pantokrator limestone, Ammonitico Rosso, Posidonia Shales, Vigla limestone, Upper Senonian limestone, Palaeocene-Eocene limestone and Oligocene “flysch”. The major tectonic features of the regions are folds with their axes trending SW-NE at the northern part and NNW-SSE to NNE-SSW southern of the Mousiotitsa-Episkopiko-Petrovouni fault system and the strike-slip fault systems of Ziros and Petousi.

The evaluation of the daily meteorological data revealed that December is the most humid month of the year followed by January, whereas July and August are the driest months. Approximately 40-45% of the annual precipitation is distributed during the winter time and 30% during autumn. The mean annual precipitation ranges from 897.4 to 2051.8 mm and the precipitation altitude relationship suggests an increased precipitation with altitude at a rate of 84 mm/100 m. The maximum temperature is recorded during August and it may reach 40°C and the minimum during January. The temperature variation with the altitude is calculated at 0.61°C/100 m. The maximum solarity time is 377.8 h, recorded during July at the Arta station. December displays the highest relative humidity with a value of 84.2% recorded again at the Arta station. The highest wind velocity values are recorded at the Preveza station and similar velocities are also recorded at the Ioannina station. The real evapotranspiration in Louros drainage basin ranges between 27-39%. The potential evapotranspiration was calculated from the Ioannina station meteorological data, which are considered more representative for Louros basin, at 785.8 mm of precipitation according to Thornthwaite and at 722.0 mm according to Penman-Monteith.

According to the SAC-SMA algorithm the total discharge (surficial and underground) for the years 2008-2010 ranges between 61-73% of the total precipitation. The algorithm simulates the vertical percolation of rainwater in both unsaturated and saturated zones taking into account 15 parameters including the tension water capacity of the unsaturated zone, the maximum water storage capacity of both unsaturated and saturated zones, the water amount escaping into deeper horizons and not recorded at the basin’s outlet, the percentage of impermeable ground which is responsible for instant runoff, etc. These parameters are correlated to the hydrograph and are recalculated according to it. Two interesting aspects were pointed out from the discharge measurements and the algorithm application. The first is related to the maximum amount of free water, which can be stored at the basic flow of the karstic system, which is very high for the whole basin, reaching 1200 mm of precipitation and the second is the amount of water filtered to the deeper horizons, which reaches 0.098.

The discharge of individual karstic units was simulated applying the specialized MODKARST code. The code, which transforms precipitation to discharge resolving mathematical equations of non-linear flow using the mass and energy balance, successfully completed the time series of available data of spring discharge measurements for the period between the years 2008-2010.

Additionally, a number of useful parameters including spring recharge, delay period between precipitation and discharge, the storage capacity of the discharge area were also calculated by the MODKARST code. These data enabled the calculation of the annual infiltration coefficient for each one of the 15 springs and for the whole basin; the latter was found to range between 38-50% of annual precipitation. The total supply area was estimated approximately at 395 km2, which is consistent with the area of Louros hydrogeological basin calculated from hydrogeological data.

The 18 sets of water table measurements, each one corresponding to a different period, revealed that the aquifers of the intermediate part of Louros basin, which are developed in Quaternary alluvial sediments, are laterally connected to the carbonate formations of the individual karstic spring units, forming a common aquifer with a common water table.

Groundwater flow follows a general N-S direction from the topographic highs to the coastal area with local minor shifts to NE-SW and NW-SE directions. The artificial lake at the position of the Public Power Corporation’s Dam at the south of the region is directly connected to the aquifer and plays an important role in water-level variation. The water table contours display a higher gradient to the southern part due to the decreased hydraulic conductivity of the limestones close to Agios Georgios village. The decreased hydraulic conductivity is believed to be the reason for the development of the homonymous spring although the hydraulic load distributions suggest the extension of the aquifer to the south and a relation to the water level in Ziros Lake, boreholes and the Priala springs. The hydraulic gradient in the broader region ranges between 4-16‰. The absolute water level variation between dry and humid season ranges from 2 m at the South to 15-20 m to the North with an average of 9 m.

The hydrological balance of Louros River mountainous basin according to the aforementioned data is calculated as follows: The total precipitation between the years 2008-2010 ranged between 5.67E+08-9.8E+08 m3 and the discharge at Pantanassa site between 3.47E+08-6.83E+08 m3. The real evapotransiration ranged between 29-39% of the precipitation. The total discharge (runoff and groundwater) accounted for 61-73% of the precipitation, whereas the basic flow due to the percolation ranged between 34-38%. Considering a mean water level variation of 9 m, between the dry and humid season, the water amount constituting the local storage is 2025Ε+07 m3.

Statistical evaluation on spring discharge data and the recession curves analysis revealed three distinct levels with diverse karstic weathering along Louros basin coinciding to the upper, intermediate and low flow of Louros River, respectively. The developed karstic units are generally complex but simple individual units develop as well. The response of spring discharge to the stored water amounts is immediate but with relatively large duration suggesting the storage of large quantities of water and a well-developed system of karstic conduits, which however has not yet met its complete evolution. The karst spring’s units are homogeneous and each one is distinguished from different recession coefficients.

The three levels of flow are also distinguished from the duration curves, which point to individual units upstream, complex units receiving and transmitting water to the adjacent ones in the middle part and complex that only receive water from the upper. This distinguishment is also enhanced by the groundwater’s major ion concentrations, which reveal Ca-HCO3 water-type upstream, along with the isotopic composition at the same part. The prevalent Ca-HCO3-Cl-SO4 water-type in the middle part, the Na-Ca-Cl-SO4 water-type downstream and isotope variation confirms this distinguishment. Moreover, REE variation is also consistent with the three levels. The assumption of relatively large stored water reserves, which contribute to analogous “memory” of spring karstic units, as pointed out by autocorreletion functions is enhanced from SAC-SMA algorithm which premises an increased capacity at the lower zone of basic flow, as well as from the hydrochemical and isotopic composition of groundwater. Monitoring of the seasonal variation in groundwater composition revealed minor variations of hydrochemical parameters and remarkably stable isotopic composition. Both aspects can be explained by the existence of a considerable water body acting as a retarder to external changes.

The crosscorrelation functions suggest a well-developed karstic system, which however has not yet reached its complete maturity also confirmed from field observations. The same conclusion is extracted from the homogeneous evolution at the interval of each karstic unit as demonstrated from recession curves on spring hydrographs.

The results from hydrochemical analyses also revealed the effect of evaporitic minerals and phosphate-rich rocks in groundwater composition and confirmed the hydraulic relationships between surface and groundwater.

The study of the isotopic composition also contributed to exclude the potential connection between the Ioannina and Louros basins, confirmed the meteoric origin of groundwater and revealed the effect of seawater in the chemical composition of few sampling sites.

The microbiological research only revealed minor incidents of contamination and significant attenuation of microorganisms during periods of high discharge.

Cure from the cave: volcanic cave actinomycetes and their potential in drug discovery, 2013, Cheeptham N. , Sadoway T. , Rule D. , Watson K. , Moote P. , Soliman L. C. , Azad N. , Donkor K. K. , Horne D.

Volcanic caves have been little studied for their potential as sources of novel microbial species and bioactive compounds with new scaffolds. We present the first study of volcanic cave microbiology from Canada and suggest that this habitat has great potential for the isolation of novel bioactive substances. Sample locations were plotted on a contour map that was compiled in ArcView 3.2. Over 400 bacterial isolates were obtained from the Helmcken Falls cave in Wells Gray Provincial Park, British Columbia. From our preliminary screen, of 400 isolates tested, 1% showed activity against extended spectrum ß-lactamase E. coli, 1.75% against Escherichia coli, 2.25% against Acinetobacter baumannii, and 26.50% against Klebsiella pneumoniae. In addition, 10.25% showed activity against Micrococcus luteus, 2% against methicillin resistant Staphylococcus aureus, 9.25% against Mycobacterium smegmatis, 6.25% Pseudomonas aeruginosa and 7.5% against Candida albicans. Chemical and physical characteristics of three rock wall samples were studied using scanning electron microscopy and f lame atomic absorption spectrometry. Calcium (Ca), iron (Fe), and aluminum (Al) were the most abundant components while magnesium (Mg), sodium (Na), arsenic (As), lead (Pb), chromium (Cr), and barium (Ba) were second most abundant with cadmium (Cd) and potassium (K) were the least abundant in our samples. Scanning electron microscopy (SEM) showed the presence of microscopic life forms in all three rock wall samples. 16S rRNA gene sequencing of 82 isolates revealed that 65 (79.3%) of the strains belong to the Streptomyces genus and 5 (6.1%) were members of Bacillus, Pseudomonas, Nocardia and Erwinia genera. Interestingly, twelve (14.6%) of the 16S rRNA sequences showed similarity to unidentif ied ribosomal RNA sequences in the library databases, the sequences of these isolates need to be further investigated using the EzTaxon-e database (http://eztaxon-e. to determine whether or not these are novel species. Nevertheless, this suggests the possibility that they could be unstudied or rare bacteria. The Helmcken Falls cave microbiome possesses a great diversity of microbes with the potential for studies of novel microbial interactions and the isolation of new types of antimicrobial agents.

Surface morphology of gypsum karst, 2013, Gutierrez F. , Cooper A. H.

This chapter reviews gypsum karst landforms with special emphasis on the features that are distinctive from those of carbonate karst. The differences between gypsum and carbonate karst landscapes are largely related to the higher solubility of the gypsum, its lower mechanical strength, more ductile rheology, and the higher extent of interstratal dissolution processes, commonly associated with the presence of other salts at depth. The landforms reviewed include subsidence morphostructures caused by interstratal karstification (large depressions, monoclines, folds, basins and domes, karst grabens, and breccia pipes), fluvial terraces affected by synsedimentary subsidence, sinkholes, poljes, karren, tumuli, and polygons, as well as landslides controlled by gypsum dissolution

Hydrogeological approach to distinguishing hypogene speleogenesis settings, 2013, Klimchouk, A. B.

The hydrogeological approach to defining hypogene speleogenesis (HS) relates it to ascending groundwater flow (AF). HS develops where AF causes local disequilibria conditions favoring dissolution and supports them during sufficiently long time in course of the geodynamic and hydrogeological evolution. The disequilibrium conditions at depth are invoked by changing physical-chemical parameters along an AF paths, or/and by the interaction between circulation systems of different scales and hydrody-namic regimes. The association of HS with AF suggests a possibility to discern regulari-ties of development and distribution of HS from the perspectives of the regional hy-drogeological analysis. In mature artesian basins of the cratonic type, settings favorable for AF and HS, are as follows: 1) marginal areas of discharge of the groundwaters of the 2nd hydrogeological story (H-story), 2) zones of topography-controlled upward cir-culation within the internal basin area (at the 1st and, in places, at the 2nd H-stories; 3) crests of anticlinal folds or uplifted tectonic blocs within the internal basin area where the upper regional aquitard is thinned or partially breached; 4) linear-local zones of deep-rooted cross-formational faults conducting AF from internal deep sources across the upper H-stories. Hydrodynamics in the 3rd and 4th stories is dominated by ascending circulation strongly controlled by cross-formational tectonic structures. Specific circula-tion pattern develops in large Cenozoic carbonate platforms (the Florida-type), side-open to the ocean, where AF across stratified sequences in the coastal parts, driven by both topography-induced head gradients and density gradients, involves mixing with the seawater. The latter can be drawn into a platform at deep levels and rise in the plat-form interior (the Kohout’s scheme). In folded regions, AF and HS are tightly con-trolled by faults, especially those at junctions between large tectonic structures. In young intramontaine basins with dominating geostatic regime, HS is favored at margin-al discharge areas where circulation systems of different origins and regimes may inter-act, such as meteoric waters flows from adjacent uplifted massifs, basinal fluids expelled from the basin’s interiors, and endogenous fluids rising along deep-rooted faults. Spe-cific and very favorable settings for HS are found in regions of young volcanism with carbonate formations in a sedimentary cover

Superposed folding and associated fracturing influence hypogene karst development in Neoproterozoic carbonates, São Francisco Craton, Brazil, 2015,

Porosity and permeability along fractured zones in carbonates could be significantly enhanced by ascending fluid flow, resulting in hypogene karst development. This work presents a detailed structural analysis of the longest cave system in South America to investigate the relationship between patterns of karst conduits and regional deformation. Our study area encompasses the Toca da Boa Vista (TBV) and Toca da Barriguda (TBR) caves, which are ca. 107 km and 34 km long, respectively. This cave system occurs in Neoproterozoic carbonates of the Salitre Formation in the northern part of the São Francisco Craton, Brazil. The fold belts that are around and at the craton edges were deformed in a compressive setting during the Brasiliano orogeny between 750 and 540 Ma. Based on the integrated analysis of the folds and brittle deformation in the caves and in outcrops of the surrounding region, we show the following: (1) The caves occur in a tectonic transpressive corridor along a regional thrust belt; (2) major cave passages, at the middle storey of the system, considering both length and frequency, developed laterally along mainly (a) NE–SW to E–W and (b) N to S oriented anticline hinges; (3) conduitswere formed by dissolutional enlargement of subvertical joints,which present a high concentration along anticline hinges due to folding of competent grainstone layers; (4) the first folding event F1was previously documented in the region and corresponds with NW–SE- to N–S-trending compression, whereas the second event F2, documented for the first time in the present study, is related to E–Wcompression; and (5) both folding  еvents occurred during the Brasiliano orogeny. We conclude that fluid flow and related dissolution pathways have a close relationship with regional deformation events, thus enhancing our ability to predict karst patterns in layered carbonates.

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