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Enviroscan Ukrainian Institute of Speleology and Karstology


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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 lateral moraine is a glacial deposit at the flank of a glacier, often constituted by debris from valley walls [16].?

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 moisture (Keyword) returned 64 results for the whole karstbase:
Showing 16 to 30 of 64
Stalagmite luminescence and peat humification records of palaeomoisture for the last 2500 years., 1998,
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Baker Andy

Physical response of a karst drainage basin to flood pulses: Example of the Devil's Icebox cave system (Missouri, USA), 1998,
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Halihan T. , Wicks C. M. , Engeln J. F. ,
In karst aquifers, water moves from the recharge area (sinkhole plains and swallets) to the discharge area (springs), traveling kilometers through the groundwater system in a period of hems to days. Transit rimes through karst aquifers are a function of the conduit geometry and connectedness, intensity and duration of the recharge event, and antecedent soil moisture. Often many of these factors are unknown or difficult to quantify. Therefore, predicting the response of a karst basin to recharge is difficult. Numerous researchers have attempted to understand the response of a karst basin, but a good understanding of whether the response is dependent on local features or regional effects is currently lacking. From April 1994 to May 1995, flood pulse hydrographs from a karst aquifer with well-developed and well-documented conduits (Devil's Icebox cave system) were obtained from a gaging station near the spring of the karst basin. Data were also collected from within the conduit system in an attempt to determine whether flow was locally controlled by constrictions in the conduits. Based on an application of Bernoulli's equation, analyses of the changes in kinetic head and potential head over time indicated local control during storm events. The observed sediment patterns and water level variations also support localized flow control during storm events. A numerical model of the constrictions was rested and reproduced the responses observed at the spring during initial periods of storm events. The model illustrated that the constricted flow was very sensitive to recharge. It also illustrated the transition from local control due to constriction to regional controls due to the aquifer matrix. (C) 1998 Elsevier Science B.V

Flared slopes revisited, 1998,
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Twidale C. R. , Bourne J. A. ,
Flared slopes are smooth concavities caused by subsurface moisture-generated weathering in the scarp-foot zone of hillslopes or boulders. They are well represented in granitic terrains but also developed in other massive materials such as limestone, sandstone, dacite, rhyolite, and basalt, as well as other plutonic rocks. Notches, cliff-foot caves, and swamp slob are congeners of flared slopes. Though a few bedrock flares are conceivably caused by nivation or by a combination of coastal processes, most are two-stage or etch forms. Appreciation of the origin of these forms has permitted their use in the identification and measurement of recent soil erosion and an explanation of natural bridges. Their mode of development is also germane to the origin of the host inselberg or bornhardt and, indeed, to general theories of landscape evolution. But certain discrepancies have been noted concerning the distribution and detailed morphology of flared slopes. Such anomalies are a result of structural factors (sensu late), of variations in size of catchment and in degree of exposure, and of several protective factors. Notwithstanding, the original explanation of flared slopes stands, as do their wider implications

Microclimate Study of Kartchner Caverns, Arizona, 1999,
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Buecher, R. H.
A detailed two-year study of the microclimate in Kartchner Caverns determined that the most significant problem in maintaining the microclimate of the cave is the potential for drying out due to increased airflow. Two factorsa small, hypothesized upper second entrance and a slight geothermal warming of the cavecontrol natural airflow and increase the amount and intensity of winter air exchange. The average amount of water reaching the cave is 7.9 mm/yr, only twice the amount lost by evaporation from cave surfaces. Kartchner Caverns has an average relative humidity (RH) of 99.4%. Useful measurement of RH required a dewpoint soil psychrometer rather than a sling psychrometer. Moisture loss from cave surfaces is proportional to relative humidity, and small changes in RH have a dramatic effect on evaporation from cave surfaces. A lowering of RH to 98.7% would double the evaporation rate and start to dry out the cave. The volume of air exchange in the cave was estimated from direct measurement, changes in CO2 concentration, and temperature profile models. All of these methods are consistent with a volume of 4,000 m/day entering the cave during the winter. During the summer, the direction of airflow reverses and the volume of air leaving the cave is much smaller than during the winter months. Surface air is almost always drier than cave aironly during the summer months when rain occurs does outside air contain more moisture. However, the rate of air exchange is greatly reduced during the summer, which minimizes any potential effect of increased outside moisture. Radon concentrations in the cave are high enough to be of concern for long-time employees but not for the general public. Radon222 concentrations average 90 pCi/L and radon daughters average 0.77 Working Levels (WL) in the main part of the cave. During the winter, radon levels in the Echo Passage are up to six times higher than the rest of the cave due to the passages stable microclimate and limited air movement, which greatly reduces radon removal by plateout. Natural removal by ventilation is only a minor factor in determining radon levels in the rest of the cave.

Variations in stalagmite luminescence laminae structure at Poole's Cavern, England, AD 1910{}1996: calibration of a palaeoprecipitation proxy, 1999,
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Baker A, Proctor Cj, Barnes Wl,
Duplicate records of variations in the structure of stalagmite annual luminescence laminae are investi gated for the period ad 1910 to 1996 for Poole's Cavern, Buxton, central England. For the two stalagmites, 88% of the years have luminescence laminae that exhibit a near sinusoidal shape with no structural variations. However 10 laminae (12% of total) exhibit a double band structure; these are demonstrated to occur in years with high monthly or daily mean precipitation. It is suggested that high intensity (.60 mm d- 1) and high quantity (.250 mm per month) of precipitation may flush luminescent organic material onto the stalagmites from either the soil or groundwater zones and generate a double lamina. However, not all precipitation events generated double laminae. High-intensity events in summer were ineffective due to a soil moisture deficit and/or interception by the woodland canopy. High-rainfall months (.250 mm) failed to generate double laminae when preceded by two or more months of greater than 150 mm, suggesting exhaustion of the organic acid supply can occur. When compared to monthly precipitation data for Buxton, laminae shape and the percentage of double laminae of the Poole's Cavern stalagmites are best explained by a centre-weighted running mean of the preceding six to seven months' precipitation. The palaeoclimate potential of structural variations in stalagmite luminescence laminae is discussed

Speleothem evidence for Holocene fluctuations of the prairie-forest ecotone, north-central USA, 1999,
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Denniston Rf, Gonzalez La, Baker Rg, Asmerom Y, Reagan Mk, Edwards Rl, Alexander Ec,
Carbon and oxygen isotopic trends from seven Midwestern speleothems record significant offsets in the timing of middle-Holocene vegetation change. Interactions of dry Pacific and moist Gulf of Mexico air masses maintained a sharp moisture gradient across Iowa, Minnesota, and Wisconsin such that the arrival of prairie was offset by 2000 years between caves and pollen sites located only 50 km apart. Oxygen isotopes shift concomitantly with carbon in most cases, although these changes are believed to represent increased evaporative enrichment of 18O prior to infiltration during the prairie period

Comparative study of a stalagmite sample by stratigraphy, laser induced fluorescence spectroscopy, EPR spectrometry and reflectance imaging, 2000,
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Perrette Yves, Delannoy Jean Jacques, Bolvin Herve, Cordonnier Michel, Destombes Jean Luc, Zhilinskaya Elena A. , Aboukais Antoine,
In the last few years, it has been shown that multi-proxy data are recorded in speleothems and that these secondary deposits can be used to retrieve records of environmental evolution in extra-glacial continental conditions. The goal of many current research is to obtain a better understanding of the processes leading to the growth of these chemical sediments and to relate them to changes in environmental conditions. In the present research, the multi-proxy study of a well-laminated speleothem sample points out the interest of reflectance trend measurement as a water excess indicator. Results from stratigraphy, laser induced fluorescence spectroscopy, EPR spectrometry and reflectance imaging have been combined in order to get a better understanding of the environmental conditions pertaining during speleothem growth. Several parameters have been measured: (i) Mn2 concentration evolution (shown to be linked to soil processes); (ii) linewidth [Delta]H of the low field Mn2 EPR line (linked to crystalline properties of the speleothem); (iii) intensities of the laser excited fluorescence (linked to organic matter content of calcite) and reflectance (linked to calcite porosity); (iv) wavelength [lambda]peak of the intensity maximum of laser excited fluorescence bands (linked to the size of trapped organic molecules). Other data resulting from statistical treatment of the annual fluorescence cycles have also been used. Significant correlations demonstrate the covariation of [lambda]peak and calcite reflectance with the hydrological regime of the cave. In the well drained soils of a karstic area, Mn2 and [lambda]peak appear to be accurate proxies for soil moisture evolution, directly linked to the water excess. These results are confirmed by the comparison with historical knowledge of environmental changes of the surrounding plateau

Doline morphogenetic processes from global and local viewpoints, 2000,
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Gams, Ivan

Geomorphogenetical processes of solution dolines are evident from restraints in their global and local distribution: more precipitation than potential evapotranspiration, permeable soil cover, water level and solution front (transition from aggressive to flowstone depositing water) below shallow epikarst, slope inclination below 30°, solid soluble rock. Dolines are an effect of local accelerated solution. In initial phase they are connected with more fractured stone, as the grains have greater specific (surface/volume) surface exposed to soil moisture. Effect of stone fracturing on solution was tested in laboratory. Later growth of basin is based on automatism, as the size of soil/stone interface is increased with deepening of the basin. Funnel-like dolines with growth usually convert in a bowl-like form with greater exceeding. The form is controlled also by water permeability of soil and solifluction. In temperate climate the two million year long Pleistocene offered with more moisture from snow and with intensive fracturing of stone better conditions for doline development than the warmer Neogene and Holocene when man's impact in last centuries essentially redused primary forest environment and thus processes in the basins. Collapse dolines are not taken into account.


The distribution of plants in Scoska Cave, North Yorkshire, and their relationship to light intensity, 2001,
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Pentecost Allan, Zhaohui Zhang
The flora of a small limestone cave was investigated. A total of 59 species was recorded (4 algae, 3 lichens, 47 bryophytes, 4 ferns, 1 angiosperm) making it bryologically the richest cave in Britain and one of the richest in Europe. All but nine of the species had been recorded from other European caves. Species-richness declined irregullarly from the entrance (relative irradiance with respect to open sky 12%) to 34m depth (rel. irradiance 0.004%). Bryophytes were found at 0-16m depth where relative irradiance declined to 0.2% and only algae were encountered at 34m depth. While irradiance, which declined exponentially, was the major factor controlling plant distribution, substratum characteristics and surface moisture were also important.

Geophysical surveys over karst recharge features, Illinois, USA, 2001,
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Carpenter Pj, Ahmed S,
Karst aquifers supply a significant fraction of the world's drinking water. These types of aquifers are also highly susceptible to pollution from the surface with recharge usually occurring through fractures and solution openings at the bedrock surface. Thickness of the protective soil cover, macropores and openings within the soil cover, and the nature of the weathered bedrock surface all influence infiltration. Recharge openings at the bedrock surface, however, are often covered by unconsolidated sediments, resulting in the inadvertent placement of landfills, unregulated dump sites, tailing piles, waste lagoons and septic systems over recharge zones. In these settings surface geophysical surveys, calibrated by a few soil cores, could be employed to identify these recharge openings, and qualitatively assess the protection afforded by the soil cover. In a test of this hypothesis, geophysical measurements accurately predicted the thickness of unconsolidated deposits overlying karstic dolomite at a site about 100 km south of Chicago, Illinois. Zones of elevated electrical conductivity and high ground-penetrating radar (GPR) attenuation within the sediments coincided with subcropping solutionally-enlarged hydraulically active bedrock fractures. These fractures extend to over 12-m depth, as shown by 2-D inverted resistivity sections and soil coring. Anomalous electromagnetic (EM) conductivity and GPR response may be due to higher soil moisture above these enlarged fractures. An epikarstal conduit at 2.5-m depth was directly identified through a GPR survey. These results suggest that surface geophysical surveys are a viable tool for assessing the susceptibility of shallow karst aquifers to contamination

Intra- and inter-annual growth rate of modern stalagmites, 2001,
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Genty D, Baker A, Vokal B,
We measure the factors that determine growth rate (temperature, drip rate, calcium ion concentration) for 31 waters that feed stalagmites within six cave systems throughout Europe. Water samples were collected at a frequency of at least month. to permit the modelling of both inter- and intra-annual growth rate variations, utilising the theory of Wolfgang Dreybrodt (Chem. Geol. 29 (1980) 89-105; Chem. Geol, 32 (1981) 237-245; Dreybrodt, W., 1988, Processes in Karst Systems. Springer-Verlag, Berlin 288 pp.). Inter-annual growth rates were measured using the stalagmites that were associated with the analysed water samples; growth rate was determined from annual lamina counting, specific time markers within the stalagmites, and location of bomb C-14. When compared to theoretically predicted values, a good agreement between theoretical and measured stalagmite growth rates is observed (R-2 = 0.69). When compared to site climate and geochemical parameters, a good correlation is observed between measured growth fate and mean annual temperature for five sites (R-2 = 0.63) and dripwater calcium content (R-2 = 0.61), but not drip rate (R-2 = 0.09). The good correlation with both calcium and temperature is due to soil CO, production being primarily determined by surface temperature and soil moisture. However, when we compare our data to that in the Grotte de Clamouse, a site that has little soil cover, we observe that the growth rate-temperature relationship breaks down due to either the lack of soil CO, production or prior calcite: precipitation. Intra-annual data demonstrates that maximum growth rate occurs when calcium concentrations are high, and that this occurs under different seasons depending on the hydrology of each site. Our results demonstrate a stronger dependence of intra-annual stalagmite growth rate on dissolved calcium ion concentrations than drip rate for the range of drip rates investigated here (0.01 < t < 2drip s(-1)), but for lower drip rates, this factor becomes important in controlling growth rate. We suggest that for well-monitored acid -understood sites, stalagmite growth rate variations can provide useful information for palaeoclimate reconstruction. (C) 2001 Elsevier Science B.V. All rights reserved

Geochronology of late Pleistocene to Holocene speleothemsfrom central Texas: Implications for regional paleoclimate, 2001,
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Musgrove Marylynn, Banner Jay L. , Mack Larry E. , Combs Deanna M. , James Eric W. , Cheng Hai, Edwards R. Lawrence,
A detailed chronology for four stalagmites from three central Texas caves separated by as much as 130 km provides a 71 000-yr record of temporal changes in hydrology and climate. Mass spectrometric 238U-230Th and 235U-231Pa analyses have yielded 53 ages. The accuracy of the ages and the closed- system behavior of the speleothems are indicated by interlaboratory comparisons, concordance of 230Th and 231Pa ages, and the result that all ages are in correct stratigraphic order. Over the past 71 000 yr, the stalagmites have similar growth histories with alternating periods of relatively rapid and slow growth. The growth rates vary over more than two orders of magnitude, and there were three periods of rapid growth: 71-60 ka, 39-33 ka, and 24-12 ka. These growth-rate shifts correspond in part with global glacial-interglacial climatic shifts. Paleontological evidence indicates that around the Last Glacial Maximum (20 ka), climate in central Texas was cooler and wetter than at present. This wetter interval corresponds with the most recent period of increased growth rates in the speleothems, which is consistent with conditions necessary for speleothem growth. The temporal shift in wetness has been proposed to result from a southward deflection of the jet steam due to the presence of a continental ice sheet in central North America. This mechanism also may have governed the two earlier intervals of fast growth in the speleothems (and inferred wetter climate). Ice volumes were lower and temperatures in central North America were higher during these two earlier glacial intervals than during the Last Glacial Maximum, however. The potential effects of temporal variations in precession of Earth's orbit on regional effective moisture may provide an additional mechanism for increased effective moisture coincident with the observed intervals of increased speleothem growth. The stalagmites all exhibit a large drop in growth rate between 15 and 12 ka, and they show very slow growth up to the present, consistent with drier climate during the Holocene. These results illustrate that speleothem growth rates can reflect the regional response of a hydrologic system to regional and global climate variability

Soil carbon dioxide in a summer-dry subalpine karst, Marble Mountains, California, USA, 2001,
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Davis J, Amato P, Kiefer R,
Studies of the seasonality, spatial variation and geomorphic effects of Soil CO2 concentrations in a summer-dry subalpine karst landscape in the Marble Mountains, Klamath National Forest, California, demonstrate the significance of soil moisture as a limiting factor. Modeled actual evapotranspiration (AET) in the four weeks prior to sampling explains 36% of the observed soil-CO2 concentrations, pointing to the importance of root respiration processes in these systems. Late snows are significant in controlling the timing of a snowmelt-initiated pulse of respiration and groundwater. CO2 concentrations were measured at multiple sites in two seasons - 1995 and 1997 - with contrasting patterns of snowmelt. Other than wet-meadow anomalies, where CO2 concentrations reached up to 3.8% in midsummer, alpine meadows on schist were the sites of the highest spring peak concentrations of approximately 1%. Forest sites and sites with thin soils on marble typically peaked at approximately 0.5%, also within a month of snowmelt exposure. Ongoing karstification in the upper bare karst is focused in soil-filled grikes where late-season snowmelt concentrates flow during high-respiration periods, but the lack of active speleothem development suggests that the carbonate solution system is greatly reduced from preglacial periods

The role of accurate recharge estimation in the hydrodynamic analysis of karst aquifers, 2001,
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Petrič, Metka

For the karst aquifer in the background of the Vipava springs in south-western Slovenia the first the model of the recharge estimation was set on the base of the method of soil moisture balance. Additional to precipitation, the influences of the interception on vegetation cover, snow and snowmelt, evapotranspiration, water storage in soil, rapid recharge and secondary infiltration were also considered in this model. It was calibrated by comparison with the discharges of the Vipava springs and then the daily values of recharge were estimated. To test the role of such accurate estimation of the recharge in further hydrodynamic analysis of karst aquifers, the black-box method was used. As the input signal in the supposed linear system the measured precipitation was first adopted, and then the estimated recharge values. It was demonstrated by comparison of results that the introduction of the recharge function significantly improves the model. In this way the important influence of the processes in the air, vegetation and soil on the amount and the time distribution of the recharge, and through this also on the hydrodynamic functioning of karst aquifers, was proved.


Quantification of Macroscopic Subaerial Exposure Features in Carbonate Rocks, 2002,
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Budd Da, Gaswirth Sb, Oliver Wl,
The macroscopic features that characterize subaerial exposure surfaces in carbonates are well known, but their significance has not been quantitatively evaluated. This study presents such an analysis in the lower Oligocene Suwannee Limestone of west-central Florida. Eleven cores were point counted on a foot-by-foot basis for the abundance of caliche, rhizoliths, karst breccia, open vugs, infiltrated sediment, fractures, and pedogenic alteration. These features occur at and below intraformational exposure surfaces, which represent hiatuses estimated at 104 to 105 years, and an uppermost sequence-bounding unconformity representing 0.5 Myr, as revealed by Sr-isotope data. Statistical analyses of the point-count data reveal only a few significant relationships. (1) The hierarchy of exposure surfaces, and by inference duration of exposure, is differentiated only at a marginally significant level by sediment-filled vugs preferentially associated with the sequence boundary. Duration of exposure did not have a significant impact on the relative abundance of all other features. (2) Proximity (< 5 ft; 1.5 m) to any exposure surface is indicated only by rhizoliths, caliche, and pedogenic alteration, whereas karst breccia is preferentially found distal (> 5 ft) to both types of surfaces. Fractures, open vugs, and infiltrated sediment show no proximal or distal preference for either type of surface. (3) Depositional texture has no statistically significant affect on the presence or abundance of the exposure features, with the exception that rhizoliths and open vugs are preferentially more abundant in packstones relative to grainstones. This is interpreted to be the result of a soil-moisture effect. Factor analysis defines four factors that explain 46% to 52% of the total variance in the abundance data relative to the sequence boundary and the intraformational surfaces, respectively. The loading of each exposure feature on each factor is the same with respect to both types of surfaces, which is further evidence that the abundance of exposure features is independent of duration of exposure. Factor 1 is interpreted to be the amplitude of base-level changes and controls the abundance of karst breccia. Factor 2 is interpreted to be abundance of vegetation and relates to the abundance of rhizoliths and fractures. Factor 3 is interpreted to be a combination of soil-zone PCO2 and the availability of water and affects the abundance of pedogenic overprinting, caliche, and open vugs. Factor 4 is stratigraphic proximity to the sequence boundary, which controls the presence of sediment-filled voids. The amount of uncorrelated unique variance associated with infiltrated sediments, pedogenic overprinting, caliche, and open vugs is large (> 60%), meaning that feature abundance is also influenced by other unidentified site-specific factors. These results demonstrate that quantifying the abundance of macroscopic subaerial exposure features in limestones has the potential to yield more insight into the significance of those features than a mere qualitative assessment. This is particularly true when assessing the potential role of the many variables that can affect the development of these features

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