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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 gour is flowstone deposit, normally of calcite, built up along the edge of a pool due to precipitation from a thin film of overflow water. once initiated, by calcite-saturated water overflowing from floor hollows, development is selfenhancing, and the gours can grow into large dams many meters high and wide. inside the gour pool, more calcite may be precipitated as crystals or pearls. large flights of gours occur in many caves, with spectacular and well known examples around the hall of thirteen in the gouffre berger, france. large travertine, gours can form in the open air, as at band-i- amir, afghanistan [9]. see also rimstone barrage; rimstone barrier; rimstone dam.?

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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Karst environment, Culver D.C.
Mushroom Speleothems: Stromatolites That Formed in the Absence of Phototrophs, Bontognali, Tomaso R.R.; D’Angeli Ilenia M.; Tisato, Nicola; Vasconcelos, Crisogono; Bernasconi, Stefano M.; Gonzales, Esteban R. G.; De Waele, Jo
Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
Microbial mediation of complex subterranean mineral structures, Tirato, Nicola; Torriano, Stefano F.F;, Monteux, Sylvain; Sauro, Francesco; De Waele, Jo; Lavagna, Maria Luisa; D’Angeli, Ilenia Maria; Chailloux, Daniel; Renda, Michel; Eglinton, Timothy I.; Bontognali, Tomaso Renzo Rezio
Evidence of a plate-wide tectonic pressure pulse provided by extensometric monitoring in the Balkan Mountains (Bulgaria), Briestensky, Milos; Rowberry, Matt; Stemberk, Josef; Stefanov, Petar; Vozar, Jozef; Sebela, Stanka; Petro, Lubomir; Bella, Pavel; Gaal, Ludovit; Ormukov, Cholponbek;
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Your search for inception horizon (Keyword) returned 15 results for the whole karstbase:
Showing 1 to 15 of 15
The Forest of Dean Caves and Karst: Inception Horizons and Iron-Ore Deposits, 1993, Lowe D. J.

The Inception Horizon hypothesis in vertical to steeply-dipping linestone; applications in New South Wales, Australia, 1999, Osborne R. A.

Forum: Cave inception horizons in Beck Head Stream Cave, Clapham, North Yorkshire, 2000, Cordingley J.

Cave inception horizons in Beck Head Stream Cave, Clapham, North Yorkshire [Corrigendum], 2000, Cordingley J.

Dynamics of the evolution of single karst conduit, 2000, Dreybrodt W. , Gabrovsek F.
The evolution of karst conduits by calcite-aggressive water flowing in initially narrow fractures require a non-linear rate law FSUBn(c)=kSUBn(1-c/cSUB eg)SUPn for limestone dissolution close to equilibrium with respect to calcite. A mathematical analysis of the evolution of limestone dissolution rates of water in such early, narrow fractures as a function of the distance from the input reveals an exponential decrease of the dissolution rates for linear dissolution rate laws (n=1), such that subsurface karstification is prevented. For non-linear kinetics (n>2), however, the decrease of rates proceeds by a hyperbolic relation, such that dissolution rates at the exit of the fracture are still sufficiently high to create a feedback mechanism by which after a long time of gestation a dramatic increase in the widths of the conduits is established. After this breakthrough event, uniform widening along the entire channel determines the further evolution. The time to achieve breakthrough is given by T=aSUB0/2gammaF(L,0), where 2gammaF(L,0) is the initial widening in cm/year at the exit of the conduit. This however is only true when the inflow solution is at less than 99% of saturation. Otherwise the positive feedback loop is switched off and the conduit widens evenly along its entire length with rates of 10SUP-9 cm/year to enlarge extremely narrow fractures with initial widths of several ten microns over distances of kilometers to sizes of about 0.1mm within several ten millions of years. This provides a general explanation for the concept of inception horizons, where usually other mechanisms have been assumed.

Role of stratigraphic elements in speleogenesis: the speleoinception concept, 2000, 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.

Some case studies of speleogenesis by sulfuric acid, 2000, Lowe D. J. , Bottrell S. H. , Gunn J.
Minerals that can weather to produce sulfuric acid directly or indirectly, with or without microbial mediation, occur as trace components in most carbonate sequences, but they are more concentrated at specific horizons. The latter comprise beds of atypical lithology, together termed inception horizons, and they are commonly associated with breaks between major depositional cycles. Some cycle boundaries are marked by concentrations of sulfide minerals, particularly pyrite, that are readily oxidized to generate sulfuric acid. Cycle boundaries may also be marked by the presence of primary evaporite minerals such as gypsum, and their removal by direct dissolution or by their reduction to hydrogen sulfide may be implicated in early porosity development. Though few caves in carbonate sequences are largely, or entirely, the product of calcite dissolution by sulfuric acid or of evaporite removal, such processes may play an important role in cave inception. This chapter examines a number of situations where processes other than carbonic acid dissolution have played an important role in secondary porosity generation and influenced subsequent speleogenesis.

Review: Evolution of caves and the inception horizon hypothesis, 2000, Goede, Albert

Review of a paper by OSBORNE, R.A., 1999: The inception horizon hypothesis in vertical to steeply-dipping limestone: applications in New South Wales, Australia. Cave and Karst Science, 26(1), 5-12.


The hydrogeology of crystalline rocks as supporting evidence for tectonic inception in some epigean endokarsts, 2006, Faulkner, Trevor
This paper reviews the considerable advances made in recent years to understand the processes leading to the creation of the triple porosity hydrogeology described for karstic limestones. These have concentrated on the physics and chemistry of slow karst dissolution during the inception phase of conduit evolution in sedimentary limestones prior to 'breakthrough', and then considered the subsequent and more rapid phreatic enlargement into networks with high hydraulic conductivity. However, it is not only soluble rocks that can exhibit significant conductivities. A review of the literature of the hydrogeology of 'crystalline' (i.e. igneous and metamorphic) non-carbonate 'hard rocks' that dates from the late-1980s reveals that such rocks can also act as aquifers, especially near the surface. Their discharges supply natural springs and household wells and boreholes, flood mines, and put at risk the underground containment of hazardous wastes. Fractures are utilised within the crystalline rocks (which have negligible primary porosity, and which are assumed not to develop solutional conduits), so that flow rates can exceed the breakthrough point that, in limestones, would mark the transition from laminar to turbulent flow conditions, and fast dissolution. Similar processes should also apply to metamorphic limestones, and, indeed, to sedimentary limestones, some of which are now known to exhibit open fractures created by seismic or aseismic tectonism. In these cases, the slow chemical inception phase may be bypassed, because some karst passages may develop under phreatic conditions, at high wall-retreat rates, immediately after the inundation of epigean fractures formed tectonically. New models of speleogenetic initiation should therefore recognise both the appropriateness of the (chemical) Inception Horizon Hypothesis for the development of deep, long-range, conduits over long periods of time, as well as the importance of fast speleogenesis initiated by tect***[record truncated]***.

Evidence of inception horizons in karst conduit networks, 2009, Filipponi M, Jeannin Py. , Tacher L.

This paper outlines the conclusion from an analysis of 18 large cave systems around the world, comprising more than 1500 km of conduits. The 3D geometry of complex cave systems have been analysed in relation to their geological context as well as their hydrogeological boundary conditions. The methodology allowed for the first time statistical evidence of the inception horizon concept. Thereby it confirms 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 is particularly susceptible to the development of karst conduits because of physical, lithological or chemical deviation from the predominant carbonate facies within the limestone sequence. It passively or actively favours the localisation of dissolutional voids. The methodology based on detailed geological 3D models and cave survey allowed us to demonstrate the existence of inception horizons in karst conduit genesis. This fact improves significantly the prediction of karst conduits, knowledge that is of relevance for geological engineering problems (e.g. tunnelling, oil industry, hydrogeology) as well as for the scientific understanding of the evolution of karst systems.


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.


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.


Morphometric analysis of three-dimensional networks of karst conduits, 2011, Pardoiguzquiza Eulogio, Duranvalsero Juan J. , Rodriguezgaliano Victor

The main idiosyncrasy of a typical karst system is the presence of a three-dimensional network of conduits behaving as drains in the system and being responsible of both the quick response of karst springs to rainfall events and the complex distribution of solutes in the system. A morphometric analysis of the three-dimensional geometry of conduits provides quantitative measures that can be used in a range of applications. These morphometric parameters can be used as descriptors of the underground geomorphology, they provide information on speleogenesis processes, they can be correlated with karst denudation ratios, they can be used to control the simulation of realistic stochastic karst networks of conduits, and they can be correlated with hydrogeologic behaviour of the karst system. The main purpose of this paper is to define, describe and illustrate a range of morphometric indexes and morphometric functions that can be calculated nowadays because the availability of three-dimensional topographies provided by speleological work and the availability of the computational and graphical power provided by modern computers. Some of the morphometric parameters describe the existence of preferential directions of karstification, others describe the kartification along the vertical and the possible presence of inception horizons. Other indexes describe the shape complexity of the karstic network, whilst other indexes describe spatial variability of the conduit geometry, and other parameters give account of the connectivity of the three-dimensional network. The morphometric analysis is illustrated with a three-dimensional karstic network in Southern France.
Research highlights


Development of a deep karst system within a transpressional structure of the Dolomites in north-east Italy, 2013, Sauro Francesco, Zampieri Dario, Filipponi Marco

The Piani Eterni karst system is one of the longest and deepest caves of Italy situated in the southern sector of the Dolomiti mountain range. The area where the cave was formed displays peculiar structural settings confined in a tectonic transpressive corridor between two regional thrusts (Belluno and Valsugana). During Miocene uplift of the range the inheritance of Mesozoic structures led to the formation of a deep and wide upward-branching flower (or palm tree) structure cutting the carbonate sequence and exposing the surrounding surface to karst processes after erosion. The relative lowering of the hydrologic base level, due both to the uplift of the area and then to the carving of deep glacial valleys in the Quaternary, allowed the formation of paleo-phreatic conduits at subsequently deeper levels, interconnected by vadose shafts and canyons.

This work gives a detailed tectonic interpretation of the transpressive structure and picks out the tectonic features most favorable to the karst development. A detailed statistical analysis of the distribution and orientation of the karst conduits was performed using 31 km of 3D surveys showing that the development of the cave was strictly guided by a few favorable surfaces of stratigraphic and tectonic origin. These features are known in the literature as inception horizons and tectonic inception features, respectively. Cave levels are usually related to lithologic favorable conditions associated with standings of the paleo-water table. Here we suggest that some tectonic surface geometries could have led to the opening of voids in the active tectonic phase leading to the formation of the original proto-conduit network. Different types of tectonic inception features identified in the cave were described in terms of geometry and kinematics. Tensional fractures, as well as fault plane undulations and flexural slip surfaces between beds, are described as the most favorable tectonic surfaces for the development of the conduits. Finally, we discuss why transpressional settings and related flower structures in soluble rocks can enhance the karst process allowing the formation of huge and deep karst systems.


Structural and lithological guidance on speleogenesis in quartz–sandstone: Evidence of the arenisation process, 2014,

A detailed petrographic, structural and morphometric investigation of different types of caves carved in the quartz–sandstones of the “tepui” table mountains in Venezuela has allowed identification of the main speleogenetic factors guiding cave pattern development and the formation of particular features commonly found in these caves, such as funnel-shaped pillars, pendants and floor bumps. Samples of fresh and weathered quartz–sandstone of the Mataui Formation (Roraima Supergroup) were characterised through WDS dispersive X-ray chemical analyses, picnometer measurements, EDAX analyses, SEM and thin-section microscopy. In all the caves two compositionally different strata were identified: almost pure quartz–sandstones, with content of silica over 95% and high primary porosity (around 4%), and phyllosilicate-rich quartz–sandstone, with contents of aluminium over 10% and low primary porosity (lower than 0.5%). Phyllosilicates are mainly pyrophyllite and kaolinite. SEMimages on weathered samples showed clear evidence of dissolution on quartz grains to different degrees of development, depending on the alteration state of the samples. Grain boundary dissolution increases the rock porosity and gradually releases the quartz grains, suggesting that arenisation is a widespread and effective weathering process in these caves. The primary porosity and the degree of fracturing of the quartz–sandstone beds are the main factors controlling the intensity and distribution of the arenisation process. Weathering along iron hydroxide or silt layers, which represent inception horizons, or a strata-bounded fracture network, predisposes the formation of horizontal caves in specific stratigraphic positions. The loose sands produced by arenisation are removed by piping processes, gradually creating anastomosing open-fracture systems and forming braided mazes, geometric networks or main conduit patterns, depending on the local lithological and structural guidance on the weathering process. This study demonstrates that all the typical morphologies documented in these quartz–sandstone caves can be explained as a result of arenisation, which is guided by layers with particular petrographic characteristics (primary porosity, content of phyllosilicates and iron hydroxides), and different degrees of fracturing (strata-bounded fractures or continuous dilational joints).

 


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