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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 denuded karst is subsoil karst or interstratal karst which has been exposed by erosion of its cover [17]. see also exposed karst; interstratal karst; subsoil karst. synonyms: (french.) karst denude; (german.) nackter karst, oberflachlicher karst; (greek.) apogymnomenon karst; (italian.) carso denudato, carso nudo; (russian.) goly karst, otkryty karst; (spanish.) karst denudado; (turkish.) belirgin karst; (yugoslavian.) ogoljeli krs (kras), goli krs kras), razkriti kras.?

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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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 pinnacles (Keyword) returned 22 results for the whole karstbase:
Showing 1 to 15 of 22
Cutters and Pinnacles in Greene County, Missouri, 1965, Fellows, L. D.

Les phnomnes karstiques des quartzites d'Afrique du Sud, 1987, Martini, J.
KARST FEATURES IN QUARTZITE OF SOUTH AFRICA - The author describes karst features developed in quartzite and also, but to a lesser extent, in weathered diabase and in wad. In quartzite, the karst is due to weathering along joints and bedding planes, producing softer areanaceous boundaries. Later, vadose caves form by piping in the weathered material, starting at a spring and progressing upstream. The karst features include dolines, swallow-holes, and caves, grouped in very localised systems. Over most of the quartzite plateaus, however, real karst features are absent and the drainage remains superficial. The only ubiquitous features, reminiscent of lapies, consist of pinnacles left after erosion of sand. As most of the time they are not associated to deep karst systems, the author proposes that they should not be considered as karst features. Other caves are developed in weathered diabase and dolomite (wad), sandwiched between resistant quartzite layers. They result from the erosion of these soft layers. The author is of the opinion that the term karst rather than pseudokarst should be used to describe this morphology developed in silica and silicate rocks. The reason is that not only the features produced compare well with the ones observed in " soluble rocks " (limestone, gypsum, etc.), but that the genetical process is very similar. It is suggested that the term pseudokarst should be used only in cases were the genesis is different.

Pile foundation problems in Kuala Lumpur Limestone, Malaysia, 1987, Bergado Dt, Selvanayagam An,
The geology and karstic nature of the Kuala Lumpur (Malaysia) limestone are described in relation to pile foundation problems of heavily loaded structures. The presence of cavities, pinnacles, cantilever slabs, floating slabs and pockets of soft silty clay and loose sand in the underlying limestone bedrock presents formidable challenges to foundation engineers. Other problems include insufficient seating and damage to pile tips due to irregular and sloping bedrock surfaces. There is also the added difficulty of detecting the location and extent of cavities. Empirical design methods and local construction techniques have been successfully used such as: (i) bridging limestone cavities and slabs by filling with concrete, (ii) utilizing numerous small diameter high yield stress piles to distribute the loads and to withstand high driving stresses, (iii) filling cavities with concrete, and (iv) using micropiles to redistribute the loads. Two case histories are presented, consisting of an access ramp and a tall building. In each of these case histories, the soil investigation methods, the pile bearing capacity calculations, the selection of pile types, the pile load tests, the pile driving criteria, and construction problems are outlined and discussed. The pile foundation used consisted of H-section, high yield stress, 355 x 368 mm, driven steel piles with capacities of 750 kN to 1280 kN for the access ramp structures and the same H-section steel piles with pile capacities of 965 kN to 1070 kN for the tall building

Les Forts de Pierre ou Stone forests de Lunan (Yunnan, Chine), 1996, Ford D. , Salomon J. N. , Williams P.
"Stone forests " are well known in Southern China. We describe the type site in Lunan County on the Yunnan Plateau at about 1800 m. "Stone forests " are a spectacular form of karren, similar to the "tsingy" of Madagascar or pinnacles of Mulu. In Yunnan they are developed in massive Permian limestones and dolomites. The "Stone forests" are high fluted towers, typically more ruiniform in dolostones, that attain 20-30m in height, exceptionally 40m. They occur in patches of several square kilometres in extent in a rolling polygonal karst landscape with about 150 m local relief Three phases of evoluti6n are recognized spanning 250 Ma from the Permian until the present: 1) Mid Permian karstification and burial by Upper Permian continental basalts, 2) Mesozoic erosion and re-karstification, then burial in the Eocene by thick continental deposits, 3) Late Tertiary and Quaternary exhumation and re-karstification. No other "Stone forests" in the world show this complexity of evolution.

A morphological analysis of Tibetan limestone pinnacles: Are they remnants of tropical karst towers and cones?, 1996, Zhang D. A. ,
Limestone pinnacles on mountain slopes in Tibet were measured for morphological analysis and the results were compared with those from tropical towers and cones on karst mountain slopes of Shuicheng, southwest China. In the form analyses, the symmetric products (P) of Tibetan pinnacles present large differences between individual pinnacles. The plan forms, represented by long/short axes ratios (R(L/S)), are mostly irregular and scattered and the diameter/height ratios (R(dfh)) reveal that the Tibetan I features could belong to any three cone or tower karat types, according to Balaze's classification of karst towers. The direction of pinnacle development seems to be primarily related to slope aspect and to geological structure. The morphological structure and orientation analyses show that pinnacle development is largely controlled by lithological and stratigraphic conditions. The closed water catchment structure, which is a basic feature in karat areas, has not been found in the limestone pinnacle areas of Tibet. The results of the form and structure analyses for the Tibetan pinnacles differ from those for tropical and subtropical karst areas. Further analysis indicates that Tibetan limestone pinnacles were formed by strong physical weathering under periglacial conditions. Four kinds of morphogenesis of the pinnacles are suggested

Phnomnes karstiques et pseudo-karstiques dans des quartzites au Burundi, 1997, Peyrot, Bernard
Central Africa, underground karstic caves are to be found in precambrian carbonated series, but also in quartzite as in the case of Burundi. The arenisation process which took place during very wet periods of intense biological activity may explain the origin of these caves and of karstic landforms such as pavements and pinnacles.

A global review of solutional weathering forms on quartz sandstones, 1997, Wray R. A. L. ,
Solutional landforms in limestone have been described for over a hundred years, but landforms of similar morphology on highly siliceous sandstones and quartzites have also been identified in a wide variety of environments and generally termed pseudokarst. These include large bedrock pinnacles and towers, caves, corridors, grikes, solution basins and runnels, and even silica speleothems. Quartzites and quartz sandstones have been held to be amongst the most chemically resistant of rocks, but the similarity, both in morphology and genetic process of many landforms developed from them to features of known solutional origin on limestone, has prompted some authors to refer to these quartzose landforms as true karst.The most detailed studies of quartzose karst landforms have been in present-day tropical regions, or areas believed to have been tropical in the geologically recent past. This concentration of research in hot-wet areas, allied with the long held assertion of the insolubility of silica, especially quartz, has led to a belief that tropical climatic conditions are necessary for karstic solution of these rocks. However, the existence of quartzose karst landforms in temperate and even sub-polar latitudes, especially where there is no evidence of prior tropical conditions, suggests that the requirement of tropical weathering is no longer tenable.The reports of these quartzose solutional landforms are widely scattered through the geomorphological and geological literature, but a comprehensive world-wide review of the range of solutional landforms on quartzose rocks has not previously been published. Because of the increasing awareness in this karst type such a summary is sorely overdue

Gypsum-karst collapse in the Black Hills, South Dakota-Wyoming, USA, 2000, Epstein, Jack B.

Intrastratal dissolution of gypsum and anhydrite in four stratigraphic units of Pennsylvanian to Jurassic age in the Black Hills of South Dakota and Wyoming has resulted in many collapse features that have developed primarily in the non-soluble overlying rocks. Subsidence has affected several areas that are undergoing urban development. Subsurface intrastratal dissolution of anhydrite in the Minnelusa Formation has produced a regional collapse breccia, extensive disruption of bedding, many dolines, and breccia pipes and pinnacles, some of which extend upwards more than 300 m into overlying strata. Recent collapse is evidenced by steep-walled dolines more than 20 m deep, collapse in water wells and natural springs resulting in sediment disruption and contamination, and fresh circular scarps surrounding shallow depressions. Many beds of gypsum are contorted because of expansion due to its hydration from anhydrite, and many gypsum veinlets extend downward along random fractures from parent gypsum beds. Several dolines are sites of resurgent springs. As the anhydrite dissolution front in the subsurface Minnelusa moves downdip and radially away from the center of the Black Hills uplift, these resurgent springs will dry up and new ones will form as the geomorphology of the Black Hills evolves. Old dolines and breccia pipes, preserved in cross section on canyon walls, attest to the former position of the dissolution front. Mirror Lake, which is expanding northwestward in a downdip direction, is a local analog of a migrating dissolution front.

Lunan "Shilin" (Stone Forest), human impact and protection of (eventual) World Heritage Site (Yunnan, China), 2001, Kranjc Andrej, Liu Hong

The Chinese expression "shilin" (stone forest) is becoming an international term meaning megakarren, that is a Čforest« of intensively corroded limestone pinnacles. The best known is Shilin near the town of Lunan. The first known description of Shilin is from 1382. Shilin is very important tourist site. Modern tourism began to develop in 1980, in 1999 the number of visitors reached over 2 million. In 1981 the whole area (350 sq. km) was protected. Under the auspices of the National Ministry of Construction material is being collected for an application to inscribe Shilin into the list of World's Natural Heritage at UNESCO. Related to human impact the most important threats are: exploitation (destruction) of limestone pinnacles as a source of rock material; the pressure of population towards the protection zone due to their increase (need for new building plots); agriculture (farming and stockbreeding) connected to soil erosion and underground water pollution (use of fertilisers); fast growth of visitor numbers. The Shilin administration introduced different protection measures: ban on rock (limestone pinnacles) exploitation in the protection zone (orientation towards afforestation); construction of new tourist facilities out of the core zone (and demolition of some of them in that zone); establishment of a special protection department within Shilin management (18 person); education of "special voluntary rangers" - recruited among highly respected persons of villages and towns in the region.

Hydrology, Hazards, and Geomorphic Development of Gypsum Karst in the Northern Black Hills, South Dakota and Wyoming, 2001, Epstein, J. B.

Dissolution of gypsum and anhydrite in four stratigraphic units in the Black Hills, South Dakota and Wyoming, has resulted in development of sinkholes and has affected formational hydrologic characteristics. Subsidence has caused damage to houses and water and sewage retention sites. Substratal anhydrite dissolution in the Minnelusa Formation (Pennsylvanian and Permian) has produced breccia pipes and pinnacles, a regional collapse breccia, sinkholes, and extensive disruption of bedding. Anhydrite removal in the Minnelusa probably dates back to the early Tertiary when the Black Hills was uplifted and continues today. Evidence of recent collapse includes fresh scarps surrounding shallow depressions, sinkholes more than 60 feet deep, and sediment disruption and contamination in water wells and springs. Proof of sinkhole development to 26,000 years ago includes the Vore Buffalo Jump, near Sundance, WY, and the Mammoth Site in Hot Springs, SD. Several sinkholes in the Spearfish Formation west of Spearfish, SD, which support fish hatcheries and are used for local agricultural water supply, probably originated 500 feet below in the Minnelusa Formation. As the anhydrite dissolution front in the subsurface Minnelusa moves down dip and radially away from the center of the Black Hills uplift, these resurgent springs will dry up and new ones will form as the geomorphology of the Black Hills evolves. Abandoned sinkholes and breccia pipes, preserved in cross section on canyon walls, attest to the former position of the dissolution front. The Spearfish Formation, mostly comprising red shale and siltstone, is generally considered to be a confining layer. However, secondary fracture porosity has developed in the lower Spearfish due to considerable expansion during the hydration of anhydrite to gypsum. Thus, the lower Spearfish yields water to wells and springs making it a respectable aquifer. Processes involved in the formation of gypsum ka 

Geological and geotechnical context of cover collapse and subsidence in mid-continent US clay-mantled karst, 2002, Cooley T,
This paper presents a synthesis of geologic and geotechnical concepts to present a unified model of conditions controlling The development of cover-collapse sinkholes and associated ground subsidence. Appropriate engineering response to the hazards associated with collapse and subsidence requires a full understanding of the underlying mechanisms that produce such effects. The geotechnical characteristics of the overlying clay mantle and occurrence of the associated cover-collapse features are not random, but rather are directly tied to the underlying water flow routes and their development through time. The clay mantle and underlying epikarst are two components of a single system, each of the components influencing the other. This paper brings together these two aspects in terms of the author's personal experience and observations as a geologist, geotechnical engineer, hydrogeologist, and caver. A summary of the basic model follows. Much of the clay mantle and pinnacled upper surface of the epikarst form while surface drainage still prevails. At this stage, the karst underdrains are insufficiently developed to transport soils, although some subsidence into cutters occurs because of dissolutional rock removal. Soil arches and macropore flow routes associated with cutters have developed by this stage. As competent deep conduits extend into the area by headward linking, the cutters with the most favorable drains are linked to the conduits first and act as attractors for the development of a tributary, laterally integrated drainage system in the epikarst. Once the most efficient cutter drains become competent to transport soils, the depressed top-of-rock and ground surfaces characteristic of dolines develop. A given doline underdrain is likely to have multiple tributary drains from adjacent cutters, which vary in soil transport competence. Soil stiffness in the clay mantle over the limestone varies as a result of the pattern of stresses imposed as the underlying rock surface is lowered by dissolution and later as soil piping locally removes soils. In the absence of karst, these soils would have developed a laterally uniform, stiff to very stiff consistency. Where soil near the soil-bedrock interface is locally removed, however, the weight of the materials overlying this void is transferred to abutment zones on the pinnacles by soil arches. Local soil loading in the abutment areas of these arches would increase at least on the-order of 50% in the case of an isolated cavity. In some cases, multiple closely spaced cutters whose soil arches have narrow, laterally constrained abutment zones bearing on the intervening pinnacles may produce substantially higher soil abutment stresses. If the clays in the abutment zones do not fail, they would respond to this increase in stress by consolidating: stiffening and decreasing in volume. The cutters spanned by the soil arches accumulate raveled soils that are 'under-consolidated', the soft zones noted between pinnacles by Sowers. A simple integral of stresses analysis makes it obvious, however that no continuous soft zone exists. It is the transfer of load to the pinnacles through the stiffened abutment soils that allows these locally soft areas to exist. Soil stiffness profiles from borings substantiate this pattern. Cover-collapse features develop where soil transport through cutter drains is sufficient to remove the soils from beneath these arched areas. Two types of collapse have been observed: type I collapses have an upward-stoping open void whose rubble pile is removed by transport as fast as it is generated, producing a deep, steep-sided final collapses. In some cases, multiple voids in clusters can form with narrow abutments separating them. Large collapses may involve a progressive failure of several members of a cluster, including intervening pillars. Type 2 features are soil-filled voids limited in their rate of upward growth by the rate of soil removal, have little open void space, and migrate to the ground surface as a column of soft soils, finally producing a shallow depression. The type 2 features have geotechnical significance because of their effect on settlement under imposed loads. A single underdrain system may service both types of features, the behavior of particular voids being dependent on the relative efficiencies of their drains. This behavior can also change with time because backfilling of the underdrains with soil or flushing out of the soil filling can occur with changes in hydrologic or erosional regimes

Cryptokarst: a case-study of the Quaternary landforms of southern Apulia (southern Italy), 2003, Marsico Antonella, Selleri Gianluca, Mastronuzzi Giuseppe, Sanso Paolo, Walsh Nicola

Cryptokarst is a karst developed beneath a permeable and not karstifiable formation by percolating waters. The permeable rock acts as a storage of water which feeds slow seepage and infiltration enhancing the alteration of bedrock. The resulting forms consist of depressions, filled by the covering sediments, and pinnacles. The sinking of the permeable cover can produce depressions on the topographic surface. Erosion of the cover exposes a landscape characterised by pinnacles, ruinforms and dolines. In the Apulia region, cryptocorrosion surfaces are characterized by solution pipes 4-5 meters deep and with variable width (from a few centimeters to about one meter). Pipes walls are covered by a brownish carbonate crust, from a centimeter to more than 10 centimeters thick. The continental sands are only found in these depressions. The cryptocorrosion process took place late in the Middle Pleistocene on Quaternary marine abrasion terraces covered by no-carbonate sandy-silty continental deposits. The process stopped before the Last Interglacial age in response of an abrupt climatic change that induces a calcium carbonate precipitation and the formation of a carbonate crust.

Development and Evolution of Epikarst in Mid-Continent US Carbonates, 2005, Cooley Tony L. , P. E.

This paper presents the basic elements of a conceptual model for the development of epikarst in US mid-continent, horizontally-bedded carbonates in which flow is largely confined to secondary and tertiary porosity. The model considers the development of epikarst regimes in carbonate sequences beginning shortly after non-carbonate rocks are eroded away to expose the underlying carbonates and follows this through capture of the shallow flow by deeper dissolution conduits with reorientation of the epikarst to a more vertical form. The model does not require an underlying zone of vadose flow and in many cases considers development of such a zone to depend on the water supply provided by prior development of the epikarst. It is not claimed that all epikarsts form in the accordance with this model; rather this paper presents a viable additional model for epikarst formation under appropriate starting conditions. Factors influencing the development of epikarst are a combination of: 1) the pre-karst topography and modifications to this as the system evolves, 2) the original distribution and aperture of fractures as well as the distance and orientation of physically favorable fractures relative to potential discharge points, such as existing dissolutionally-enhanced channels with low head or nearby valleys, 3) character of soil cover as this affects percolation of water to the rock, erodability of the soil, sediment filling of conduits, and transport of sediment 4) variations in availability of dissolutionally aggressive water with time and location, and 5) low solubility layers, such as shale or chert, that promote lateral flow until a penetration point can be found. These interact to form an epikarst and deeper karst system that progressively increases its capacity both by internal improvement of its flow routes and extension into adjacent areas. The availability of water needed to promote dissolution also often has a positive feedback relationship to epikarst, in which locations of most active dissolution modify their vicinity to progressively increase capture of water, which promotes further dissolution. In early stages, lateral flow through the overlying soils and along top-of-rock must dominate the groundwater flow because the relatively intact carbonates have insufficient transmissivity to convey the available recharge through the body of the rock. Top-of-rock runnels developed by a combination of dissolution of their floors and piping erosion of their roofs would carry a significant portion of the flow. Horizontally-oriented epikarst develops with discharge to local drainage. Cutters and pinnacles, collapse-related macropores, and areas of concentrated recharge would begin to form at this stage. Initial downward propagation of this system would occur mostly due to lateral flow. Mixing corrosion could occur in sumps in these lateral flow routes when fresh, percolating rainwater mixes with older water with a higher dissolved load. Should conditions be suitable, leakage from this system promotes the migration of deeper karst conduits into the area by Ewers multi-tiered headward linking. Other sources of water may also bring in such deeper conduits. Once such deeper conduits are present, the epikarst can evolve into a more vertically oriented system, at least in the vicinity of master drains into this deeper system. Former shallow epikarst routes may then plug with sediment. In some areas, deeper systems may never develop due to unfavorable conditions. The epikarst may be the only significant system in these cases. This includes the case of poor karst formers such as interbedded shales and carbonates that may have very shallow horizontal epikarst flow paths that channel shallow subsurface flows.

Aroca (domaine marin ctier, Pays basque, France) : un karst continental ennoy par les transgressions maritimes quaternaires, 2007, Vanara Nathalie , Perre Alain, Pernet Marc, Latapie Serge, Jaillet Stphane, Martine Olivier
AROCA (LITTORAL, BASQUE COUNTRY, FRANCE): A CONTINENTAL KARST DROWNED BY QUATERNARY MARITIME TRANSGRESSIONS. The rocky formations in shallow areas of the Atlantic coast are hardly known. Studies are rare because of the difficulties of direct observation (diving in always agitated, troubled water, depth between 20 and 40 m). Our first step was to make a detailed topography of a submarine plateau named Aroca, 4 km off Socoa harbour (bay of Saint-Jean-de-Luz). This plateau was already known for having a large variety of forms within a small surface (150 x 100 m). We gave names to most remarquable formations and defined five main characteristic zones: - in the exokarstic domain 1/ a top surface with channels, 2/ a dismantled surface with pinnacles; - in the endokarstic domain 3/ caves, galleries, arches; - at the limits 4/ three inclined plans, west, north and east, 5/ a cliff to the south. A typology of forms shows a predominance of ablation reliefs: aplanation, over-deepened channels, covered rooms and galleries, arches, residual pinnacles. Deposit accumulations regroup chaotic breakdown blocks, pebble accumulations and sand covers. Statement of explanations requires recognition of the nature and age of the outcrops and succession of erosional agents during the Pleistocene. Rocks are dated from Ypresien (limestones) to Bartonian (marls). Continental erosion during sea regressions is responsible of caracteristic landforms and deposits; for example wall banks, allochthonous pebbles The currently active marine erosion during sea transgressions is due to storms, tide, dissolution, biochemical action (lithophages) and gravity. We propose a paleogeographic reconstitution. After an essentially calcareous sedimentation in Eocene and an essentially marly sedimentation in Oligocene, the sea recedes during Miocene. From then, the platform, henceforward above the water, is subject to meteoric erosion. In Pliocene, evolution of the massif is isovolumic (under a marly cover and with a low hydraulic gradient). During the lower and middle Pleistocene, the erosion of the marly cover goes on. During the upper Pleistocene, the wurmian (18000 BP) marine regression allows entrenchment of the hydrographic system thanks to an increase of hydraulic gradients (classic functional karst). From 15000 years onwards, a general transgression of sea level happens by successive steps. During the Boreal, a break in transgression allows the formation of a paleo-shore at 20 to 30 m, inducing a peneplanation phase in the tidal or infratidal zone. From 7500 BP onwards, a a rapid transgression from 23 to 8, then a slower one from 8 to the present level stops karstification on the massif. At present, only marine abrasion is active and tends to obliterate the previously built landforms.

Karst processes and slope instability: some investigations in the carbonate Apennine of Campania (southern Italy), 2007, Santo A. , Del Prete S. , Di Crescenzo G. , Rotella M. ,
Some investigations carried out in the Campania Region (southern Italy) are shown concerning instability phenomena, the development of which is strongly influenced by karst. The widespread presence of carbonate massifs close to important urban centres with dense road networks creates high-risk situations in many settings of this region. Such phenomena can have very different dimensions, origin and geomorphological development, and can be traced back to the action of hypogean and epigean karst and to complex interactions with other erosional processes. In particular, among the hypogean forms, we have analysed collapse sinkholes that have developed on carbonate slopes, especially along fault lines where there are aquifers and ascent of mineralized fluids, and which are sometimes connected to strong seismic events. Among the forms connected to epikarst processes, the origin of pinnacles has been investigated. They are isolated rock pillars, whose origin depends on a particular interaction between the geostructural characteristics of the masses and the process of karstic dissolution. Moreover, a wide variety of morphologies exist that are related to the interaction between epigean and hypogean karst and other typologies of erosional processes. Among these one group is represented by caves on carbonate slopes developed in cataclastic zones, where a slow karstic process leads to the formation of upwards caves, with dimensions of some decametres, and consequently to the high production of debris downhill. Similarly, this process has been observed along slopes set on talus. Finally, the complex combination of the karstic phenomenon with the erosional wave action forms both caves and natural rock arcs along the coasts

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