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Speleology in Kazakhstan

Shakalov on 04 Jul, 2018
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

New publications on hypogene speleogenesis

Klimchouk on 26 Mar, 2012
Dear Colleagues, This is to draw your attention to several recent publications added to KarstBase, relevant to hypogenic karst/speleogenesis: Corrosion of limestone tablets in sulfidic ground-water: measurements and speleogenetic implications Galdenzi,

The deepest terrestrial animal

Klimchouk on 23 Feb, 2012
A recent publication of Spanish researchers describes the biology of Krubera Cave, including the deepest terrestrial animal ever found: Jordana, Rafael; Baquero, Enrique; Reboleira, Sofía and Sendra, Alberto. ...

Caves - landscapes without light

akop on 05 Feb, 2012
Exhibition dedicated to caves is taking place in the Vienna Natural History Museum   The exhibition at the Natural History Museum presents the surprising variety of caves and cave formations such as stalactites and various crystals. ...

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That base level is lowest level of erosion by a stream [16].?

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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 cave genesis (Keyword) returned 29 results for the whole karstbase:
Showing 16 to 29 of 29
Dachstein-Altflche, Augenstein-Formation und Hhlenentwicklung - die Geschichte der letzten 35 Millionen Jahre in den zentralen Nrdlichen Kalkalpen, 2002, Frisch W. , Kuhlemann J. , Dunkl I. , Szekely B. , Vennemann T. , Rettenbacher A.
The landscape of the central Northern Calcareous Alps (NCA) is largely determined by the celebrate elevated karst plateaus, which represent relics of the Dachstein paleosurface and can be followed as far as the eastern margin of the NCA. The Dachstein paleosurface formed in late Eocene to early Oligocene times as a karstic hilly landscape. It was modified by later erosional processes to a limited extent only and is preserved as such in the karst plateaus. In the Oligocene, the paleosurface subsided and was sealed by the Augenstein Formation, a terrestrial sequence of conglomerates and sandstones, which are only preserved in small remnants on the plateaus. The poorly and contradictingly defined terms Rax landscape" and Augenstein landscape" are not used any more. From the overall geological situation, the age of the Augenstein Formation can be inferred as Lower Oligocene to early Lower Miocene. Fission track dating on zircon support the Lower Oligocene age of the basal Augenstein sediments (only these are preserved). Their source area was situated in the south and mainly occupied by weakly metamorphosed Paleozoic sequences (Graywacke Zone and its equivalents) and the latest Carboniferous to Lower Triassic siliciclastic base of the NCA. To the west, the Augenstein Formation interfingered with the Tertiary sediments of the Lower Inn Valley. Thermal modeling of fission track data from apatite, which is contained in pebbles as an accessory phase, suggest that the Augenstein Formation attained thicknesses of locally 1.3 km, possibly even more than 2 km. Augenstein sedimentation probably ended in Early Miocene times with the onset of lateral tectonic extrusion in the Eastern Alps, which caused lowering of the relief in the source area and created a new, fault-bounded river network. In the following period, the Augenstein sediments were eroded and redeposited in the foreland molasse basin. From Pannonian times (ca. 10 Ma) on, the central and eastern NCA, and therefore also the Dachstein paleosurface, experienced uplift in pulses. The paleosurface remained preserved in those areas, where thick limestone sequences enabled subsurface erosion in cave systems and considerably reduced surface erosion. Augenstein sediments became washed into the widespread cave systems of the plateau-topped limestone massifs. The arrangement of the caves in three horizons shows that uplift of the NCA occurred in pulses separated from periods of tectonic quiescence. In our model of the evolution of the NCA since the late Eocene, the highest cave system, the surface-near ruin cave system, was probably formed during formation of the Dachstein paleosurface. The largest system, the giant cave system, formed in Upper Miocene times, i.e., in the early stage of the final uplift period of the NCA. The youngest and lowest system, the source cave system, formed in Pliocene to Quaternary times. We aimed to date material from the giant cave system by radiometric methods. U/Pb dating on speleothems from the Mammut cave (Dachstein) and the Eisriesenwelt (Tennengebirge) gave no formation age because of the low U contents; however, the isotope ratios allow to infer that the speleothems formed in pre-Pleistocene time. Quartz pebbles from the Augenstein Formation, washed into the caves before the formation of the speleothems, were analyzer for cosmogenic beryllium and aluminum isotopes in order to date the time of redeposition. The isotope contents, however, did no yield a sufficiently strong signal. Oxygen and carbon isotope ratios were determined on the Eisriesenwelt speleothem in order to receive information on climatic changes during speleothem growth. A 260 mm long core from the outer zone of the speleothem shower limited variation for the temperatures of the seeping rainwater, which caused the speleothems to form. This indicates moderate climate and thus, again, pre-Pleistocene formation of the speleothems. All these results are in accord with the supposed Upper Miocene formation age of the giant cave system. Displacement of a speleothem along a shear plane and normal faults visible on the plateaus by the offset of the actual surface testify young, partly Quaternary tectonics, which affected the NCA.

Perspectives in karst hydrogeology and cavern genesis, 2003, Ford, D. C.

Hydrogeology and speleology both began during the 19th Century. Their approaches to limestone aquifers diverged because hydrogeologists tend to measure phenomena at very local scales between drilled wells and generalize from them to basin scales, while speleologists study the large but sparse conduits and then infer conditions around them. Convergence of the two approaches with modem computing should yield important genetic models of aquifer and cave.
Genesis of common cave systems by dissolution is a three-dimensional problem, best broken down into two-dimensional pairs for purposes of analysis. Historically, the dimensions of length and depth have received most attention, especially the question of the location of principal cave genesis with respect to the water table. Between 1900 and 1950, different scientists proposed that caves develop principally (1) in the vadose zone; (2) at random depth in the phreatic zone; (3) along the water table in between. Empirical evidence suggests that these differing hypotheses can be reconciled by a four-state model in which the frequency of penetrable fissuration controls the system geometry.
For the dimensions of length and breadth (plan patterns) there is widespread agreement that dendritic (or branchwork) patterns predominate in common caves. Irregular networks or anastomose patterns may occur as subsidiary components. When hydraulic conditions in a fissure are anisotropic (the usual case), dissolutional conduit development is competitive: local hydraulic gradients are reoriented toward the first conduits to break through to outlet points, redirecting others toward them in a cascading process. Plan patterns are most complex where there have been multiple phases ("levels") of development in a cave system in response to such effects as river channel entrenchment lowering the elevation of springs.


Role of epiphreatic flow and soutirages in conduit morphogenesis: the Barenschacht example (BE, Switzerland), 2003, Hauselmann P. , Jeannin P. Y. , Monbaron M. ,
Role of epiphreatic flow and soutirages in speleogenesis: the Barenschacht example (BE, Switzerland).- Observations in the deep parts of Barenschacht allow the linkage of two existing theories about cave genesis (FORD & EWERS 1978, AUDRA 1994). The transition from vadose canyon to phreatic tube is not observed at the perennial karstwater table, but at the floodwater table. The galleries below all show phreatic morphology despite temporary vadose flow. Therefore, the boundaries of the distinct phases of cave genesis are inclined. In low-water situation, the looping galleries empty through the so-called soutirages. These form through corrosion along discontinuities and are generally found in the epiphreatic realm. The water flowing through the soutirages reaches the perennial watertable and then the spring. It seems possible that the model presented here is also valid for non-alpine caves

Kitzsteinhorn high alpine karst (Salzburg, Austria): Evidence of non-glacial speleogenesis., 2004, Audra, Ph.
Cave and karst development in a recently deglaciated alpine area (Kitzsteinhorn, Salzburg, Austria) is examined and compared to presently and previously glaciated karst regions elsewhere. Field evidence suggests that cave genesis occurs mainly during warm, interglacial periods when vegetation and soil formation provide chemically aggressive runoff during the melting season. During periods of extensive glacier coverage, the glacial contribution to karst development is restricted to surface abrasion, shaft development in pre-existing vadose caves and infill of fine-grained sediment in the epiphreatic zone. [Feichtner-Schachthhle (2573/3)]

An overview of the current research carried out in the French Western Alps karsts, 2004, Audra, Philippe

Current research encloses karst systems geomorphologic approach, recent advances in study of karst structures which date back from the Upper Miocene. Karst genesis in Western Alps is brought up by systemic analysis, according to a geomorphologic approach. It uses the "karst immunity" that conserves old drainage structures and their associated sediments. Karst landscapes can be sorted into horizontal and vertical forms. Speleothems are clearly connected to the presence of vegetation but they also record geomorphic crisis. Clastic sediments reveal mechanical erosion. This approach concludes with karst genesis and speleogenesis reconstruction, which blend together evolution stages, environment characterization and processes. Researchers reconsider the preponderant part previously attributed to glaciers. Karst appears immediately when a gradient exists and when the aquifer is stripped of its impervious cover. Such conditions occurred from the Upper Miocene and sometimes before. Karsts of the Pleistocene age are only met in the Inner Alps where cover stripping occurred later. Vertical systems composed of shaft series are old and become more complex. Field evidence refutes Ford's classification, which assigns a deep phreatic origin. A brief account of the present state of knowledge, according to region and researcher's scientific themes, allows establishing the last decade's advances. It also shows a disparity between the North and the South Western Alps, where Vercors appears to be one of the best studied massifs in the Alps.


Kitzsteinhorn high alpine karst (Salzburg, Austria): Evidence of non-glacial speleogenesis, 2004, Audra, Ph.
Cave and karst development in a recently deglaciated alpine area (Kitzsteinhorn, Salzburg, Austria) is examined and compared to presently and previously glaciated karst regions elsewhere. Field evidence suggests that cave genesis occurs mainly during warm, interglacial periods when vegetation and soil formation provide chemically aggressive runoff during the melting season. During periods of extensive glacier coverage, the glacial contribution to karst development is restricted to surface abrasion, shaft development in pre-existing vadose caves and infill of fine-grained sediment in the epiphreatic zone.

Zoloushka Cave, 2007, Andreychouk V.

In March 2007 there was a 30th anniversary of a discovery of the Zoloushka (Cinderella) Cave, which is one of the largest gypsum caves in the world. Until now over 90 km of passages of a total volume of 0.65 million m3 have been mapped. The cave was accidentally encountered by the face of a gypsum quarry in 1946, but it was not penetrated by speleologists until 30 years later. From the very beginning of exploration, the cave attracted the attention of many speleologists and later - geographers and geologists. It became a notable supplement to the family of the largest gypsum caves, which were investigated in the area of the neighboring Podolsky (Podolia) region. It appeared however not entirely similar to them: as compared to the cave systems in Podolia the Zoloushka Cave shows more voluminous passages and it is more filled with clayey sediments. The cave passages developed mainly in the upper part of the gypsum layer, which resulted in collapses in many sections. The main feature of the Zoloushka Cave is that it was artificially uncovered (in the quarry face) and it was not accessible until the gypsum layer was drained by pumping out karst water. The quarry exposed rich groundwater reservoir ? a large karst aquifer. Gradual deepening and extension of the quarry caused the increase of outflow rate and the increase of water withdrawal. In the late 1960s, when the most (18-20m) of the gypsum layer (total thickness 24-26 m) was entrenched, the karst system had been already drained. Groundwater, marking the surface of a depression cone, was preserved only in the lowest parts of the cave. The karst system became accessible to investigations. Opening of the Zoloushka maze had interrupted the natural evolution of the hydrogeological settings ? it had occurred in the moment when it was almost totally filled with water. The caves in the Podolia region underwent this stage tens of thousand years earlier. Modern draining and younger age of the Zoloushka Cave determined a specific character of its internal relief (increased moisture of deposits, lack of secondary gypsum formations which are so typical for the Pololian?s caves), and caused different processes to operate (roof subsidence, sediment drying/draining, water flows between different areas, etc.), which accompanied a sudden conversion from water-filled chambers to empty ones. It became clear from the very beginning that the cave is an extremely interesting object from a scientific point of view. The cave provided a unique opportunity to carry out multi-aspect investigations. Many phenomena and features were observed by speleologists for the first time. Morphological features of the cave, such as large cylindrical pits created by rising underground water, evidence undoubtedly a confined origin of the cave system. The morphogenetic studies in the cave have played an important role in understanding problems of karst development in this region and establishing a new (artesian) regional concept of speleogenesis. The abundance of iron-manganese deposits in the cave attracted the attention of geochemists, who determined the presence of numerous geochemical processes which occurred when the cave became drained. The cave made it possible for speleologists to study the mechanisms of sinkhole development, which is extremely important for an adequate understanding and assessment of karst hazards. The cave sediments contain numerous carbonate insertions (lithified fills of relict fissures in gypsum), which make it possible to reconstruct important palaeogeographic, palaeotectonic and palaeokarstic events. During all these years the cave has been well studied. This work represents a kind of summary of all the hitherto achievements and has a general and complex character. Many problems however remained unresolved. Therefore the aim of this work is not only to present general results of the investigations which have been carried out in the Zoloushka Cave, but also to attract the interest of specialists of different fields in order to enlarge and intensify the investigations in the cave itself and its surrounding. The book's twelve chapters deal with history of the cave discovery and study, natural conditions and karst of the region, geological environment of the cave, speleomorphogenesis, morphological structure of the cave network, hydrology, breakdown processes and sinkhole development, cave sediments, cave microclimate, life in the cave, cave genesis and age, scientific and practical importance of the cave.

In Russian, with extended abstract and captions in English and Polish.


Cave and Karst evolution in the Alps and their relation to paleoclimate and paleotopography, 2007, Audra P. , Bini A. , Gabrovš, Ek F. , Hä, Uselmann P. , Hoblé, A F. , Jeannin P. Y. , Kunaver J. , Monbaron M. , Š, Uš, Terš, Ič, F. , Tognini P. , Trimmel H. , Wildberger A.

Progress in the understanding of cave genesis processes, as well as the intensive research carried out in the Alps during the last decades, permit to summarize the latest knowledge about Alpine caves. The phreatic parts of cave systems develop close to the karst water table, which depends on the spring position, which in turn is generally related to the valley bottom. Thus, caves are directly linked with the geomorphic evolution of the surface and reflect valley deepening. The sediments deposited in the caves help to reconstruct the morphologic succession and the paleoclimatic evolution. Moreover, they are the only means to date the caves and thus the landscape evolution. Caves appear as soon as there is an emersion of limestone from the sea and a water table gradient. Mesozoic and early tertiary paleokarsts within the alpine range prove of these ancient emersions. Hydrothermal karst seems to be more widespread than previously presumed. This is mostly due to the fact that usually, hydrothermal caves are later reused (and reshaped) by meteoric waters. Rock-ghost weathering is described as a new cave genesis agent. On the contrary, glaciers hinder cave genesis processes and fill caves. They mainly influence cave genesis indirectly by valley deepening and abrasion of the caprock. All present datings suggest that many alpine caves (excluding paleokarst) are of Pliocene or even Miocene age. Progress in dating methods (mainly the recent evolution with cosmogenic nuclides) should permit, in the near future, to date not only Pleistocene, but also Pliocene cave sediments absolutely.


Constraints on alpine speleogenesis from cave morphology - A case study from the eastern Totes Gebirge (Northern Calcareous Alps, Austria), 2009, Plan Lukas, Filipponi Marco, Behm Michael, Seebacherd Robert, Jeutter Peter

The Totes Gebirge is the largest karst massif in the Northern Calcareous Alps (NCA). This paper focuses on the eastern part, where two major multiphase alpine cave systems (Burgunderschacht Cave System and DÖF–Sonnenleiter Cave System) are described with respect to morphology, hydrology, and sediments. The caves consist of Upper Miocene galleries of (epi)phreatic genesis and younger vadose canyon-shaft systems. Morphometrical analyses were used to determine the relevance of (1) cave levels (horizontal accumulations of galleries), (2) slightly inclined palaeo water tables of speleogenetic phases, (3) initial fissures, and (4) inception horizons on the development of the cave systems. (Epi)phreatic cave conduits developed preferentially along vertical faults and along only a restricted number of bedding planes, which conforms to the inception horizon hypothesis. For at least one of the systems, a development under epiphreatic conditions is certain and a hydrological behaviour in the “filling overflow manner” is likely.

Observations in further major cave systems in the Totes Gebirge identify palaeo water tables of speleogenetic phases that show inclinations of 1.5° ± 1°. Analyses of cave levels reveal distinct peaks for each cave but it is hardly possible to correlate these elevation levels between caves of different parts of the karst massif. Therefore, we conclude that cave levels (strictly horizontal) indicate speleogenetic phases or palaeo water tables respectively, but they cannot be correlated with palaeo base levels or on regional scale. An exact correlation between cave development and palaeo base levels at the surface is only possible with inclined palaeo water tables of speleogenetic phases.

For the Totes Gebirge, the inclination directions of the speleogenetic phases imply that palaeo drainage was radial and recharge was autogenic, which is in contrast to observations from other plateaus in the NCA. Differences in fracture properties seem to be the reason for the development of divergent types, according to the Four State Model. A simplified model for cave genesis and surface development in this area since the Upper Miocene is presented.


PRINCIPAL FEATURES OF HYPOGENE SPELEOGENESIS, 2009, Klimchouk A. B.

Hypogenic and hypergenic (epigenic) karst systems are regularly associated with different types, patterns and segments of flow systems, which are characterized by distinct hydrokinetic, chemical and thermal conditions. Epigenic karst systems, which had long been the focus of most karst/speleogenetic research, are predominantly local systems receiving recharge from the overlying or immediately adjacent surface. Hypogenic karst is associated with discharge regimes of regional or intermediate flow systems dominated by upward flow, although mixing with local systems is commonly involved. Hypogenic speleogenesis tends to operate over long time spans, continuously or intermittently. Its main characteristic is the lack of genetic relationship with groundwater recharge from the overlying or immediately adjacent surface. Hypogenic karst may not be expressed at the surface and is largely climate-independent. Hypogenic speleogenesis is the formation of solution-enlarged permeability structures by waters ascending through a cave-forming zone from below. It develops in leaky confined conditions although it may continue through unconfined ones. Vertical hydraulic communication across lithological boundaries and different porosity systems allows deeper groundwaters in regional or intermediate flow systems to interact with shallower and more local systems, permitting a variety of dissolution mechanisms. There is a specific hydrogeologic mechanism inherent in hypogenic transverse speleogenesis (restricted input/output) that suppresses the positive flow-dissolution feedback and speleogenetic competition seen in the development of initial flowpath networks in hypergene cave genesis, accounting for the more uniform and pervasive conduit development found in the hypogene. Hypogenic caves are found in a wide range of geological and tectonic settings, basinal through folded, being formed by different dissolutional mechanisms operating in various lithologies. Despite these variations, the resulting caves tend to display remarkable similarity in their patterns and meso-morphology, strongly suggesting that the type of ?ow system is the primary control. Hypogenic caves commonly demonstrate a characteristic suite of cave morphologies resulting from rising ?ow across the cave-forming zone, with distinct buoyancy dissolution components. Cave patterns in hypogenic speleogenesis are guided by the initial permeability structure, its vertical heterogeneities (discordance in the permeability structure between adjacent beds) and the mode of water input to, and output from, the cave-forming zone. The latter again depends on relationships between permeability structures in the cave-forming zone and formations that lie below and above. Because of its “transverse flow” nature hypogenic speleogenesis has a clustered distribution in plan view, although initial clusters may merge during further development and extend over considerable areas. Recognition of the wide occurrence, significance and specific characteristics of hypogenic speleogenesis represents a major paradigm shift in karst science that answers many questions not satisfactorily addressed previously.


Understanding cave genesis along favourable bedding planes. The role of the primary rock permeability, 2010,

Recent studies on the complex 3D geometry of large cave systems around the World allowed us to get statistical evidence of the inception horizon hypothesis. It clearly confi rmed the idea that the development of karst conduits under phreatic conditions is strongly related to a restricted number of so called inception horizons. An inception horizon is a part of a rock succession that can favour the earliest cave forming processes (Lowe 1992). In order to understand the reason(s) why a specifi c stratigraphical horizon is used for cave development we sampled 18 inception horizons of six cave systems as well as the surrounding rock mass. More than 200 rock micro-cores have been drilled and analysed to determine parameters controlling the speleogenesis, and to provide a better prediction of dissolution voids within a karstic rock mass. Th e analysis of these cores gives a fi rst idea of the diff erent properties of inception horizons. Th is paper only presents and discusses the results of the measurements of the primary rock permeability. Th e results indicate that the initial permeability contrast is not suffi cient to explain alone the concentration of karst development along inception horizons. However, it is noticed that three types of inception horizons can be distinguished: type 1, where cave inception took place within the inception horizon and where the permeability of the inception horizon was slightly higher than that of the surrounding rock mass; type 2, where inception took place at the interface between the inception horizon and the surrounding rock mass, and where the permeability of the inception horizon is slightly lower than the surrounding rock mass; type 3, where the cave development took place along bedding plane fractures.


Bell Hole Origin: Constraints on Developmental Mechanisms, Crooked Island, Bahamas, 2011, Birmingham Andrew N. , Mylroie Joan R. , Mylroie John E. , Lace Michael J.

Bell holes are vertical, cylindrical voids, higher than they are wide, with circular cross sections and smooth walls found in the ceilings of dissolutional caves primarily from tropical and subtropical settings. They range in size from centimeter to meters in height and width. The origin of bell holes has been controversial, with two proposed categories: vadose mechanisms including bat activity, condensation corrosion, and vadose percolation; and phreatic mechanisms including degassing and density convection.
Crooked Island, Bahamas has a number of caves with bell holes of unusual morphology (up to 7 m high and 1.5 m in diameter), commonly in tight clusters, requiring significant bedrock removal in a small area. In many cases, numerous bell holes are open to the surface, which requires that up to a meter or more of surface denudation has occurred since the bell hole first formed.
Surface intersection has little impact on the phreatic mechanisms, which were time limited to cave genesis from 119 to 131 ka ago, but greatly reduces the time window for later vadose mechanisms, which need to have been completed before bell hole intersection by surface denudation.
The Crooked Island observations suggest that bell hole development occurred syngenetically with flank margin cave development under phreatic conditions. Because flank margin caves develop under slow flow conditions, vertical convection cell processes are not disrupted by turbulent lateral flow and bell holes formed as a vertical phreatic dissolution signature.


Response of the Karst Phreatic Zone to Flood Events in a Major River (Bohemian Karst, Czech Republic) and its Implications for Cave Genesis, 2012, Vysok H. , Bruthans J. , k K. , Mls J.

Hydraulic and hydrochemical relationships between a medium gradient river and a karst aquifer were studied by water level and temperature logging combined with water geochemistry and d13C. The cave lakes are separated from the river by a floodplain up to 150 m wide formed by a gravel and sand layer up to 13 m thick covered with finegrained floodplain sediments. During minor discharge peaks (water level in the river , 1.5 m above the normal river stage), a water level oscillation in the cave lakes situated 40 to 190 m away from river is induced by the river level oscillation, but the river water does not enter any of the lakes. The groundwater chemistry in the cave lakes differs from that of the river water. Low bicarbonate content and high d13C values indicate that some of cave lakes’ waters have undergone CO2 degassing and calcite precipitation. During a major flood (recurrence interval . 100 years, level rising 7 m above the normal stage), the river water rapidly flooded the caves through openings in the river canyon (floodflow injection), while those connected to the river via alluvium only were flooded by an elevated groundwater stage, and the resulting water level rise was only about 50 percent of the river level increase. A simple hydraulic model was successfully used to simulate and explain the water table oscillations in the cave lakes. Flood-flow injection has recently been substantially reduced by low-permeability, fine-grained late Holocene fluvial sediments that cap coarse gravels in the river floodplain. Fast speleogenesis by flood injection would be expected in periods when the river canyon was bare or filled by gravel alone (glacial periods, transition to Holocene). Ice jams causing local increases in the river level are recognized as one of factors that can be important in speleogenesis.


Morphology of Speleothems in Primary (Lava-) and Secondary Caves, 2013, Kempe, S.

 

Caves are defined as natural underground cavities (potentially) accessible by humans. They are decorated by various forms of speleothems that have always fascinated the human explorer. Caves are divided into primary and secondary caves, that is, formed with, or long after the deposition of the rocks containing them. The largest group of primary caves is that formed by flowing lava, whereas the largest group of secondary caves is that formed in limestone. Both display specific forms of speleothems. Although primary caves can contain primary speleothems composed of the rock that formed the cave as well as secondary speleothems formed by later deposition of minerals, secondary caves in contrast contain only secondary mineral speleothems. Rock- and mineral-composed speleothems commonly have similar morphology, determined by gravity, that is, stalactites and stalagmites. However, both primary and secondary speleothems also display forms that are specific to them. Rock speleothems are composed of basalt, whereas secondary speleothems can be composed of over 250 different minerals.

In this chapter, we explore differences and similarities of primary rock- and secondary mineral-speleothems and discuss processes of their formation.


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