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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 cave balloon is see cave blister.?

Checkout all 2699 terms in the KarstBase Glossary of Karst and Cave Terms

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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.
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 timescales (Keyword) returned 17 results for the whole karstbase:
Showing 1 to 15 of 17
Evaluating hillslope stability in tropical karst , 1998,
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Gillieson, David

Residential development in the tower karst of the Kinta valley, Malaya is proceeding at a rapid pace, and many developments have been subject to damage and loss of life from landslides and rockfalls. Study was conducted at Gunung Tempurung- Gajah, a 600-metre high limestone tower. The evaluation of hillslope stability was made by geomorphological mapping including the parameters: type of slope, activity of landslides and rock stability. Over geological timescales, periodic landslides and rockfalls are a normal and expectable part of the geomorphological processes in the tower karst of the Kinta valley. The expected frequency of landslides today is difficult to determine but recourse can be made to data on the frequency of high-intensity rainfall, and examination of revegetation on landslip debris. From these data, it seems probable that minor landslides can be triggered every 2-3 years in the area, with major phases of landslide activity occurring every 20 years.

Precipitation and dissolution of reactive solutes in fractures, 1998,
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Dijk P. , Berkowit B.

The precipitation and dissolution of reactive solutes, transported under the action of fully developed laminar flow in saturated fractures, is analyzed assuming an irreversible first-order kinetic surface reaction for one component. Equations describing solute transport, precipitation and dissolution, and the evolution of fracture aperture were approximated and solved using combined analytical and numerical techniques; dimensionless transport parameters incorporated into the solutions were estimated from data available in the literature. Fractures with initially flat, linearly constricted, and sinusoidal apertures were investigated. The initial fracture geometry and the solute saturation content of the inflowing fluid have a profound effect on the reaction processes. The results show that the evolution of the solute transport and fracture geometry can be adequately described by the Damköhler and Péclet numbers. Two extreme transport regimes were identified: relatively uniform evolution of fracture apertures and nonuniform evolution of fracture apertures restricted to the inlet region of fractures. In the case of precipitation with half-life times of the order of seconds to years and with fluid residence times of the order of minutes to days, the time for a fracture to close completely is of the order of days to millions of years. This is consistent with the order of magnitude of hydrogeological timescales. In the model the process of dissolution is the inverse of precipitation, although the combined solute transport and reaction processes are irreversible. These results and the applied dimensionless analysis can be used as a basis for the development of more complex models of reactive solute transport, precipitation, and dissolution in saturated fractured media.

Why and how are caves "organized": does the past offer a key to the present, 1999,
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Lowe, David J.

Many caves within carbonate (and perhaps other) rock sequences display marked spatial organization, particularly a tendency to group within vertical clusters. Most past explanations of clustering involve "recent" effects and interactions. New ideas, based on study of "denuded" or "unroofed" caves, acknowledge but re-interpret features and relationships that were observed long ago and commonly dismissed as "atypical", "irrelevant" or "impossible". Some traditional explanations of vertical clustering must now be re-assessed. Assumptions that any stratigraphical (bedding plane) or joint/fault fissure in carbonate rock provides (or provided) a de facto route for fluid transfer, and hence a focus for void development, are not confirmed by observation. Primitive pre-cave, but potentially cavernous, carbonate masses are not inevitably active hydrologically; nor are they geologically homogeneous. New evidence, and re-evaluation of earlier observations, implies that dissolutional void "inception" is related to a minor subset of all stratigraphical partings, which dominate initially, imprinting incipient guidance for later cave development. Recognition of this fundamental role provides a possible key to understanding the organization of cave systems and necessitates acceptance of an expansion of speleogenetic timescales back to the time of diagenesis.

Role of stratigraphic elements in speleogenesis: the speleoinception concept, 2000,
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Lowe D. J.
Inception, the earliest phase of cave development, may begin during diagenesis. Within sedimentary rock sequences inception is generally related to specific favorable horizons or zones within the rock mass. These relatively thin inception horizons tend to display atypical chemical and/or physical properties, compared to the primary properties of the bulk of potentially cavernous rock successions. Commonly they correspond to depositional breaks or interruptions, particularly boundaries between major depositional cycles. Thus, according to the Inception Horizon Hypothesis, inception in sedimentary sequences (as typified by carbonate rocks) is inevitably related to, and guided by, thin relatively impure layers within thicker, otherwise pure beds, or at boundaries between impure and pure lithologies. Growth of incipient voids occurs potentially across the full lateral extent of inception horizons, generally very slowly during extended timescales. Growth may progress simultaneously at more than one stratigraphic level in a sequence, in deeply buried, confined or artesian conditions. Voids along individual inception horizons can be linked hydrologically by others that form concurrently or subsequently along tectonic or lithogenetic fissures. Later, interference between the imprinted inception framework and evolving surface landscapes leads to structurally advantageous elements of the potential three dimensional network being selected, linked and enlarged to form the skeletons of developing cave systems.

Timescales for nitrate contamination of spring waters, northern Florida, USA., 2001,
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Katz B. G. , Bohlke J. K. , Hornsby H. D.

Timescales for nitrate contamination of spring waters, northern Florida, USA, 2001,
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Katz B. G. , Bohlke J. K. , Hornsby H. D. ,
Residence times of groundwater, discharging from springs in the middle Suwannee River Basin, were estimated using chlorofluorocarbons (CFCs), tritium ((3) H), and tritium/helium-3 (H-3/He-3) age-dating methods to assess the chronology of nitrate contamination of spring waters in northern Florida. During base-flow conditions for the Suwannee River in 1997-1999, 17 water samples were collected from 12 first, second, and third magnitude springs discharging groundwater from the Upper Floridan aquifer. Extending age-dating techniques, using transient tracers to spring waters in complex karst systems, required an assessment of several models [piston-flow (PFM), exponential mixing (EMM), and binary-mixing (BMM)] to account for different distributions of groundwater age. Multi-tracer analyses of four springs yielded generally concordant PFM ages of around 20 2 years from CFC- 12, CFC- 113, H-3, and He-3. with evidence of partial CFC- 11 degradation. The EMM gave a reasonable fit to CFC- 113, CFC- 12. and H-3 data, but did not reproduce the observed He-3 concentrations or H-3/He-3 ratios, nor did a combination PFM-EMM. The BMM could reproduce most of the multi-tracer data set only if both endmembers had H-3 concentrations not much different front modern values. CFC analyses of 14 additional springs yielded apparent PFM ages from about 10 to 20 years from CFC- 113, with evidence of partial CFC- 11 degradation and variable CFC-12 contamination. While it is not conclusive, with respect to the age distribution within each spring, the data indicate that the average residence times were in the order of 10-20 years and were roughly proportional to spring magnitude. Applying similar models to recharge and discharge of nitrate based on historical nitrogen loading data yielded contrasting trends for Suwanee County and Lafayette County. In Suwance County, spring nitrate trends and nitrogen isotope data were consistent with a peak in fertilizer input in the 1970s and a relatively high overall ratio of artificial fertilizer/manure whereas in Lafayette County, spring nitrate trends and nitrogen isotope data were consistent with a more monotonic increase in fertilizer input and relatively low overall ratio of artificial fertilizer/manure. The combined results of this study indicate that the nitrate concentrations of springs in the Suwannee River basin have responded to increased nitrogen loads from various sources in the watersheds over the last few decades, however, the responses have been subdued and delayed because the average residence time of groundwater discharging from springs are in the order of decades. (C) 2001 Published by Elsevier Science B.V

Palaeowaters in European coastal aquifers -- the goals and main conclusions of the PALAEAUX project, 2001,
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Edmunds Wm,
The PALAEAUX project has brought together up-to-date geochemical, isotopic and hydrogeological information on coastal groundwaters across Europe in a transect from the Baltic to the Canary Islands. These data have been interpreted in relation to past climatic and environmental conditions, as well as extending and challenging concepts about the evolution of groundwater near the present day coastlines. Groundwater movement beyond the present coastline as well as emplacement on shore to greater depths (up to 500 m) than allowed by the present-day flow regime has occurred, hence offshore freshwater reserves are inferred in some coastal areas. The main attributes of palaeowaters, in terms of water quality, are their high bacterial purity, total mineralization that is often less than that of modern waters and being demonstrably free of anthropogenic chemicals. However, in the Mediterranean coastal areas, lower recharge leads to higher salinity conditions in both palaeo- and modern waters. Freshwater of high quality originating from different climatic conditions to the present day, when the sea level was much lower, is found at depth beneath the present-day coastline in several countries. Recharge is shown to have been more or less continuous during the past 100 ka, even beneath the ice, as demonstrated by groundwaters from Estonia, having {delta}O values of c. -22%o. However, elsewhere (UK and Belgium) an age gap can be recognized indicating that no recharge took place at the time of the last glacial maximum. Devensian recharge temperatures (soil air temperatures) were some 6{degrees}C colder across Europe than at the present day. The development of aquifers in Europe during the past 50-100 a, by abstraction from boreholes, has generally disturbed flow systems that have evolved over varying geological timescales, especially those derived from the Late Pleistocene and Holocene. Hydrogeophysical logging has demonstrated time and quality stratified aquifers resulting in mixed waters being produced on pumping. A range of specific indicators, including 3H, 3H/3He, 85Kr, chlorofluoro-carbons and pollutants, have been used to recognize the extent to which waters from the modern (industrial) era have penetrated into the aquifers, often replacing the natural palaeogroundwaters. In the coastal regions, many problems for management are identified, including issues relating to quantity and quality of water, seasonal demand, pollution risks and ecosystem damage, requiring a new look at legislation

Multiresolution cross-analysis of rainfall rates and karstic spring runoffs, 2002,
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Labat D. , Ababou R. , Mangin A. ,
In order to quantify the quality of the rainfall/discharge relationship across time-scales, we propose the use of both orthogonal wavelet multiresolution analysis and cross-correlation analysis. By using the two techniques together, it is possible to show, scale-by-scale, the influence of the input to the system (rainfall) on the response (discharge) of the aquifer and also to relate these results to the internal structure of the aquifer and to the degree of organisation of the karst drainage. An application of this method to three Pyrenean karsts is also shown

Rainfall-runoff relations for karstic springs: multifractal analyses, 2002,
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Labat D. , Mangin A. , Ababou R. ,
Karstic watersheds appear as highly as non-linear and non-stationary systems. The behaviour of karstic springs has been previously studied using non-linear simulation methods (Volterra expansion) and non-stationary analyses methods based on wavelet transforms. The main issue of karstic spring behaviour consists of the presence and the identification of characteristic time-scales. In order to highlight more precisely the scale-properties of the rainfall-runoff relations for karstic springs, the multifractal analysis is introduced. These methods are applied daily and half-hourly rainfall rates and runoffs measured on a three French karstic springs located in the Pyrenees Mountains (Ariege, France): Aliou, Baget and Fontestorbes. They are characterised by a variable development of the drainage systems. We have at our disposal long and uninterrupted series of data over period of several years, which constitute a high quality bank data. Multifractal analyses of both daily and half-hourly rainfall rates and runoffs give evident a scale-dependant behaviour. Effectively, it highlights the presence of different multifractal processes at each sampling rate. Using a universal class of multifractal models based on cascade multiplicative processes, the identified multifractal sub-processes are characterised by the classical parameters alpha and C-1. All these results should lead to several improvements in karstic springflow simulation models. (C) 2002 Elsevier Science B.V. All rights reserved

High-resolution magnetostratigraphy of speleothems from Snežna jama, Kamnik-Savinja Alps, Slovenia, 2002,
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Bosá, K Pavel, Hercman Helena, Mihevc Andrej, Pruner Petr

The Snežna jama Cave is located in the Kamnik-Savinja Alps, NE Slovenia, in a Raduha Ridge. The cave is a huge, more or less horizontal fossil phreatic/epiphreatic conduit. It is penetrated by vertical shafts - invasion vadose (proglacial) caves. Close to the cave entrance, there is about 3 m high wall composed of speleothems - a complex sequence of flowstone with numerous breaks in deposition, six of them are principal. The lower part of the profile (about 85 cm) contains abundant terrigenous component (terra rossa-derived clay). Stalagmites developed in several periods are completely buried by nearly horizontal younger sequences of flowstone. Continuous speleothem log was recovered from the profile in a total length of about 2.4 m. The rock column was cut to cubes in the laboratory (2x2x2 cm) and studied both by thermal demagnetisation (23 samples, 12 steps - 20 to 620 °C) and alternating field method (98 samples, 14 steps - 1 to 100 mT). Magnetic properties identified the lithological boundary. In contrast to the upper part, the lower one shows both higher magnetic susceptibility and higher remanent magnetisation. The turn point can indicate important palaeogeographical change. Magnetostratigraphic log is composed of 7 normal and 6 reverse polarised magnetozones. The age of speleothems detected by the U-series alpha-counting spectrometry falls outside the method range, i.e. over 350 ka. Uranium isotopic equilibria indicate the age over 1.2 Ma. The age of the fill is pre-Quaternary, clearly older than 1.77 Ma. The most probable age from correlation with geomagnetic polarity timescales is about 3.0 to 5.0 or 1.8 to 3.6 Ma. Both possibilities can indicate the growth rate of speleothems of about 1.1 to 1.3 m per 1 Ma. The age of speleogenesis can be compared to some of unroofed caves in the area of the Classical Karst (SW Slovenia) connected with the Messinian period. Snežna jama was uplifted to high altitudes by younger (Plio-Pleistocene) uplift of the Alpine chain.

Concurrent tectonism and aquifer evolution > 100,000 years recorded in cave sediments, Dinaric karst, Slovenia, 2003,
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Sasowsky I. D. , Sebela S. , Harbert W. ,
A natural conduit that had formed along a fault was exposed in Upper Cretaceous limestones during construction of a tunnel near Postojna,. Slovenia. The conduit is filled with poorly indurated clastic sediments. Slickensides found on the margin of the sediment deposit show sinistral fault motion that is consistent with regional tectonism. Analysis of the sediments revealed reversed magnetic polarity. The minimum age for latest movement on the fault, origin of the cave, and deposition of these sediments is 780 ka. Present-day tectonic stresses are concordant with the fault movement, and it is likely that the fault has been continuously active throughout growth, infilling, and hydrologic abandonment of the conduit. Based upon known and modeled growth rates for conduits, this system is recording a period of growth and abandonment that exceeds 100,000 years. The role that rock discontinuities play in groundwater flow may vary over these timescales, and it may be important to account for tectonism when evaluating the long-term evolution of aquifers

Palaeoenvironments in semi-arid northeastern Brazil inferred from high precision mass spectrometric speleothem and travertine ages and the dynamics of South American rainforests, 2004,
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Auler A. S. , Wang X. , Edwards R. L. , Cheng H. , Cristalli P. S. , Smart P. L. , Richards D. A.

Understanding past environmental changes in tropical rainforests is extremely important in order to assess the response of such environments to present and future climatic changes and understand causes and the present patterns of biodiversity.
Earlier hypothesis on the origin of biodiversity have stressed the role of past climatic changes in promoting speciation. According to the “refuge hypothesis” (Haffer, 1982), dry periods could have led to forest fragmentation, isolating more humid forested zones (called refuges) within an environment largely dominated by savannas. The refuge hypothesis does not assign timescales for rainforest fragmentation, although recent studies have suggested that speciation could have occurred over timescales of millions of years (Knapp and Mallet, 2003). Although the focus of heavy criticism (Colinvaux, et a., 2000), the refuge hypothesis has generated a large amount of research. In general, pollen studies (Colinvaux, et a., 1996, Haberle and Maslin, 1999) tend to support a continuous forest cover throughout late Quaternary climatic shifts, although large variations in rainfall have also been demonstrated by other pollen and isotopic studies (van der Hammen and Absy, 1994; Maslin and Burns, 2000).
Amazon and Atlantic rainforests are the two major forested zones in South America. Amazon rainforest, the largest rainforest in the world, comprise a total original area of 4.1 million km2 and is renowned for hosting the large biodiversity in the world (30% of all the world’s known plant and animal species). Atlantic rainforest, also a biodiversity hotspot, occurs along the coast and has been subjected to heavy deforestation since European arrival. Nowadays only c. 7% of its original forested area of 1.3 million km2 remains. These two rainforests are separated by drought-prone semi-arid northeastern (NE) Brazil. Our study does not address the refuge hypothesis directly although it sheds new light on the dynamics of forest expansion in the past as well as indicates alternative ways of promoting speciation. It has long been hypothesized, due to botanical (Mori, 1989; Andrade-Lima, 1982) and faunistic (Costa, 2003) similarities, that the Amazon and Atlantic rainforests were once linked in the past. Although numerous connecting routes have been postulated (Bigarella, et al, 1975; Por, 1992; De Oliveira, et al, 1999), the timing of forest expansion and their possible recurrence have remained elusive.
The study area lies in the driest portion of NE Brazil “dry corridor”, close to the village of Laje dos Negros, northern state of Bahia. Mean annual precipitation is around 480 mm and potential evapotranspiration is in excess of 1,400 mm/year (Fig.1). Present vegetation comprises a low arbustive scrubland known locally as caatinga. The area contains a well-developed underground karst (Auler and Smart, 2003) with abundant secondary calcite precipitates, both underground (speleothems) and on the surface (travertines).

Sources of nitrate contamination and age of water in large karstic springs of Florida, 2004,
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Katz B. G. ,
In response to concerns about the steady increase in nitrate concentrations over the past several decades in many of Florida's first magnitude spring waters (discharge greater than or equal to2.8 m(3)/s), multiple isotopic and other chemical tracers were analyzed in water samples from 12 large springs to assess sources and timescales of nitrate contamination. Nitrate-N concentrations in spring waters ranged from 0.50 to 4.2 mg/L, and delta(15)N values of nitrate in spring waters ranged from 2.6 to 7.9 per mil. Most delta(15)N values were below 6 per mil indicating that inorganic fertilizers were the dominant source of nitrogen in these waters. Apparent ages of groundwater discharging from springs ranged from 5 to about 35-years, based on multi-tracer analyses (CFC-12, CFC-113, SF6, H-3/He-3) and a piston flow assumption; however, apparent tracer ages generally were not concordant. The most reliable spring-water ages appear to be based on tritium and He-3 data, because concentrations of CFCs and SF6 in several spring waters were much higher than would be expected from equilibration with modern atmospheric concentrations. Data for all tracers were most consistent with output curves for exponential and binary mixing models that represent mixtures of water in the Upper Floridan aquifer recharged since the early 1960s. Given that groundwater transit times are on the order of decades and are related to the prolonged input of nitrogen from multiple sources to the aquifer, nitrate could persist in groundwater that flows toward springs for several decades due to slow transport of solutes through the aquifer matrix

Dynamic hydrologic and geochemical response in a perennial karst spring, 2004,
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Winston W. E. , Criss R. E. ,
Storms induce rapid variations in the discharge, specific conductivity, and temperature of a perennial karst spring in eastern Missouri that are followed by gradual return to normal conditions. These dynamics reflect the varying relative proportions of 'base flow'' and 'event water'' components that have different delta(18)O signatures, solute concentrations, flow paths, and transport timescales, which combine with other transport impedances to govern the temporal behavior of water quality parameters. A new Darcian model accurately reproduces the hydrograph and its separated components, defines the time constants that govern their physical and geochemical responses, and affords a quantitative method to investigate these linked behaviors. Analysis of 58 storm events reveals an average pulse time constant of 0.4 0.2 days that is much shorter than the similar to2 year residence time of water in the aquifer derived from long-term delta(18)O variations. For individual pulses this short time constant for total flow approximates that of the base flow component, but the time constant for the event water component is even shorter. The same model also approximates other storm-induced variations and indicates they are all triggered at the same time but respond according to different time constants of 1.6 0.2 days for oxygen isotopes, 1.6 0.9 days for temperature, and 3.4 1.0 days for specific conductivity and major ion concentrations. The time constant for discharge decreases somewhat with greater peak flows, while the geochemical time constants increase

Cave inception and development in Caledonide metacarbonate rocks. PhD thesis, 2005,
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Faulkner, Trevor Laurence

This is the first comprehensive study of cave inception and development in metacarbonate rocks. The main study area is a 40000km2 region in central Scandinavia that contains over 1000 individual metacarbonate outcrops, and has nearly 1000 recorded karst caves (with passage lengths up to 5.6km). The area, which was repeatedly glaciated in the late Cenozoic, comprises a suite of nappes in the Cambro–Silurian Caledonides, a paleic range of mountains with terranes presently occurring on both sides of the northern Atlantic. Information about the stripe karst and non-stripe karst outcrops and their contained caves was assembled into computer-based databases, enabling relationships between the internal attributes of the caves and their external geological and geomorphological environments to be analysed. A rather consistent pattern emerged. For example, karst hydrological system distances are invariably shorter than 3.5km, and cave passages are positioned randomly in a vertical dimension, whilst commonly remaining within 50m of the overlying surface. This consistency is suggestive that the relevant cave inception, development and removal processes operated at a regional scale, and over long timescales. A consequence of the epigean association of caves with the landscape is that cave development can only be understood in the context of the geomorphological evolution of the host region. A review of the latest knowledge of the inception and development of caves in sedimentary limestones concluded that the speleogenesis of the central Scandinavian caves cannot be explained by these ideas. Five new inter-related conceptual models are constructed to explain cave development in metacarbonate rocks in the various Caledonide terranes. These are:
1. The tectonic inception model - this shows that it is only open fracture routes, primarily created by the seismic shocks that accompany deglaciation, which can provide the opportunity for dissolution of metalimestone rocks that have negligible primary porosity.
2. The external model of cave development - this black-box approach reveals how the formation, development and destruction of the karst caves are related to the evolution of their local landscape. During the Pleistocene, these processes were dominated by the cycle of glaciation, leading to cyclic speleogenesis, and the development of ever-longer and deeper systems, where the maximum distance to the surface commonly remains within one-eighth of the extent of change in local relief.
3. The hydrogeological model - this demonstrates that the caves developed to their mapped dimensions in timescales compatible with the first two models, within the constraints imposed by the physics and chemistry of calcite dissolution and erosion, primarily in almost pure water. Relict caves were predominantly formed in phreatic conditions beneath active deglacial ice-dammed lakes, with asymmetric distributions on east- and west-facing slopes. Mainly vadose caves developed during the present interglacial, primarily vadose, conditions, with maximum dimensions determined by catchment area. Combination caves developed during both deglacial and interglacial stages. The cross-sections of phreatic passages obey a non-fractal distribution, because they enlarged at maximum rates in similar timescales. Phreatic cave entrances could be enlarged at high altitudes by freeze / thaw processes at the surface of ice-dammed lakes, and at low altitudes by marine activity during isostatic uplift.
4. The internal static and dynamic model of cave development - this white-box approach demonstrates that many caves have ‘upside-down’ morphology, with relict phreatic passages overlying a single, primarily vadose, streamway. Both types of passage are guided along inception surfaces that follow the structural geology and fractures of the carbonate outcrops. Dynamically, the caves developed in a ‘Top-Down, Middle-Outwards’ (TDMO) sequence that may have extended over several glacial cycles, and passages in the older multi-cycle caves were removed downwards and inwards by glacial erosion.
5. The Caledonide model - this shows that the same processes (with some refinements) applied to cave development in most of the other (non-central Scandinavian) Caledonide areas. The prime influences on cave dimensions were the thicknesses of the successive northern Atlantic glacial icesheets and the positions of the caves relative to deglacial ice-dammed lakes and to local topography. Other influences included contact metamorphism, proximity to major thrusts, and marine incursions. With knowledge of these influences for each area, mean cave dimensions can be predicted.
The thesis provides the opportunity for the five models to be extended, so that cave development in other glaciated metamorphic and sedimentary limestones can be better understood, and to be inverted, so that landscape evolution can be derived from cave data.

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