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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 longitudinal fault is a fault having the same direction of strike as the surrounding strata [16].?

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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;
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Your search for scour (Keyword) returned 19 results for the whole karstbase:
Showing 1 to 15 of 19
Karst development in Ordovician carbonates: Western Platform of Newfoundland, Master of Science (MS) Thesis, 1978, Karolyi, Marika Sarolta

The Appalachian fold belt system in Newfoundland is divided into three tectonic divisions: Western Platform; Central Mobile Belt; Avalon Platform Rocks of the Western Platform range in age from Precambrian to Carboniferous. Major karst areas are found there is Ordovician and Carboniferous rocks. Karst features of the study area (Goose Arm to Bonne Bay Big Pond) are in the Ordovician carbonates of the undivided St. George and Table Head Formations, covering a few hundred square kilometers. Features include karren, sinkholes, sinking streams, and karst springs, caves and other solutional and collapse features.
In the study area multiple fold and faulting episodes complicate the geology. Extensive and probably repeated glaciations have produced rugged terrane with U-shaped valleys and as much as 300m relief on the carbonates. There is variable but thick till cover. A class or classes of ice-scoured closed depressions with internal drainage are recognized. Postglacial karst forms are limited to varieties of karren (mainly littoral), small sinkholes, and cave systems that are inaccessively small in most instances. Distribution of all karst features is highly irregular.
Hydrologic patterns follow fluvial, fluviokarstic and holokarstic drainage. Large number of sinking ponds have seasonal overflow channels. The ground water drainage routes are generally short and shallow, with varied hydraulic gradients. Few instances of ground water route integration to regional springs is found.
The water chemistry of the area displays a tight normal distribution of hardness. This is attributed to the ponding effect. Seasonal trends show an overall increase in total hardness and other parameters, with some ponds showing linear increases and others cyclic variations.
Karst type and distribution is complex and irregular, but both glaciokarstic and karstiglacial development is present. The majority of karst forms point to karstiglacial development where previous karst forms have been modified by ice. Karstification is controlled by geology, rock lithology, hydraulic gradients and glacial scour and infill. Karstic processes continue to operate today, modifying the scoured basins and creating new karst forms.


Karst features of a glaciated dolomite peninsula, Door County, Wisconsin, 1990, Johnson Scot B. , Stieglitz Ronald D. ,
A geologic investigation of the northern part of Door Peninsula, Wisconsin for a state funded water quality project revealed that karstification of the Silurian aquifer is more extensive than previously believed. Sinkholes and small insurgent features, solution modified crevices, pavements, caves and springs were inventories and mapped. These features are generally smaller and less densely developed than those in most limestone terranes; however, they are important to the geomorphology and water quality of the peninsula.Continental glaciation has strongly influenced both the distribution and the present surface morphology of the karst features. Ice scour has formed a stepped bedrock topography, contributed to pavement formation and may have removed some preglacial features. Deposition has plugged and masked features in places. In addition, subglacial water circulation, and ice loading and unloading may have influenced karst development

Alpine karsts. Genesis of large subterranean networks. Examples : the Tennengebirge (Austria) - the Ile de Crémieu, the Chartreuse and the Vercors (France), PhD Thesis, 1993, Audra, Philippe

This work, based on the study of several underground alpine networks, aims to propose some milestone in the history of these karstic regions.

The first part of the work is made up of three regional studies.

The Tennengebirge mountains are a massif of the limestone High Alps in the region of Salzburg in Austria. A cone karst close to the base level developed in the Neogene. Streams from the Alps fed the karst, resulting in the huge horizontal networks of which the Eisriesenwelt provides evidence. During the successive phases of upthrust, the levels of karstification, whether on the surface or deeper down, settled into a tier pattern, thus descending in stages from the base level. From the Pliocene era onwards, thanks to an increase in potential, alpine shafts replace the horizontal networks. The formation of these shafts is more pronounced during glaciation. The study of the Cosa Nostra - Bergerhöhle system developing 30 km of conduits on a gradient reaching almost 1 500 m provides a fairly full view of the karstification of this massif. It includes the horizontal levels developed in the Miocene and the Plio-Pleistocene, joined together by vertical sections. The most noteworthy features of the Tennengebirge, as in the neighboring massifs, lie first and foremost in the extreme thickness of the limestone which has recorded and immunized the differents steps of karstification. Secondly, the size of the networks can be, for the most part, accounted for by the contribution of allogenous waters from the streams of the Neogene and the glaciers of the Pleistocene. Generally sudden and unexpected, these flows of water engendered heavy loads (up to 600 m), simultaneously flooding several levels. To a lesser extent, the situation is similar today.

The Ile de Cremieu is a low limestone plateau on the western edge of the Jura. Due to its location in the foothills, the lobes of the Rhône glacier have covered it up, obliterating the surface karst. However, widespread evidence of anteglacial morphologies remains : paleokarst, cone karst, polygenic surface. Because of glacial plugging, access to the underground karst is limited. The main cavity is the cave of La Balme. Its initial development dates back to an early period. The morphological study has permitted the identification of several phases which go back to the Pleistocene and which are related to the Rhône glacier. The latter brought about modifications in the base level by supplying its merging waters as well as moraine material. These variations in the base level shaped the drainage structure. The underground glacial polishes are one of the noteworthy aspects recorded.

The massives of the Moucherotte and dent de Crolles belong to the northern French Prealps. They conceal large networks, respectively the Vallier cave and the Dent de Crolles. They were formed in the early Pliocene after the final orogenic phase and are in the form of horizontal conduits. The upthrust, which brought about the embanking of the Isère valley, left them in a perched position by taking away the basin which fed them. They were later, however, able to take advantage of waters from the Isère glacier during a part of the Pleistocene. The Vallier cave contains particularly glacio-karstic sediments of the lower Pleistocene, representing unique evidence of glaciation during this period. The vertical networks were put in place at the end of the Pliocene with the increase in karstification potential ; they underwent changes in the Pleistocene due to the effect of autochton and allogenous glaciers.

The second part of the work deals in general with the various forms and processes of karstification, sometimes going beyond the Alps. The study of cave deposits is a privileged tool in the understanding and reconstruction not only of the history of the networks but also the regional environment. The dating of speleothems by the U / Th method has very ofen given an age of over 350 000 years. The age of the networks is confirmed by the use of paleomagnetism which has yielded evidence of speleothems and glacio-karstic sediments anterior to 780 000 years. Anisotropic measurements of magnetic susceptibility have been used to distinguish the putting into place of glacio-karstic deposits by decantation.

Measurements of calcite rates lead to a typology of sediments based on their nature and carbonate content (rehandled weathered rocks, fluvial sands, carbonated varves, decantation clays). Granulometry confirms this differenciation by supplying precise details of transport and sedimentation modes : suspension and abrupt precipitation of clay, suspension and slow decantation of carbonated varves, suspension and rolling together with a variable sorting of sand and gravel. Mineralogical analyses oppose two types of detrital deposits. On the one hand, the rehandling of antequaternary weathered rocks extracted by the karst as a result of scouring during environmental destabilization and on the other hand, sediments characteristic of the ice age of the Pleistocene. The latter are not highly developed and their arrival in the karst is always later. Examination of heavy minerals, the morphoscopy of quartz grains and study of micromorphologies on thin blades provide precise details of conditions of evolution. The use of these methods of investigation allows for an accurate definition of the features of the evolution of the differents types of fillings, particularly speleothems, rehandled weathered rocks as well as carbonated varves. This wealth and complexity are emphasized by a detailed study of the sedimentary sequences of the Vallier cave and of the Bergerhöhle.
Speleogenesis is approached last of all in the light of above study. Emphasis is placed on the major part played by corrosion in the temporarily phreatic zone and on its many consequences (multi-level concept, simultaneous evolution of levels, origin of deep waterlogged karsts…).
Varia tions in the base level have induced karstification in contexts in which the potential was weak. These were followed by periods of increased potential to which were added the effects of glaciation. Perched horizontal levels belong to the first stages which ended in the early Pliocene, whereas alpine shafts developed in the second context. The role of structure and the parameters governing the shape of conduits (pits, meanders, canyons) are also dealt with. The different parts of the karst are borne in mind when dealing with the strength of karstic erosion during the ice age. It notably appears that it is weak on the crests and more or less non-existent in the deep parts of the karst which are liable to flooding. Finally, a preliminary analysis of an observation of neotectonic traces is presented.


Rapports entre la karstification _primditerranenne et la crise de salinit messinienne, lexemple du karst lombard (Italie), 1994, Bini, A.
The Mediterraean dessiccation theory suggests that during the Messinian the Mediterranean sea lad almost completely dried up did a thick succession of evaporites was laid down Due to dessiccation the erosional base level through the whole Mediterranean area was lowered, with the consequent development of long and deep fluviatile canyons (e.g. Nile, Rhne, Var, etc). This lowering strongly affected karst evolution This paper concerns the karst in Lombardy, around the southalpine lakes. The old evolutionary models, predating dessiccation theory, assume that the lacustine valleys were scoured by the quaternary glaciers. ln this case the karst should have been characterized by some features, like for example the altitudinal cave distribution as a consequence of the valley lowering after each glaciation. Seismic experiments through the lakes and their tributaries have shown that these valleys are deep fluviatile canyons. The study of caves has demonstrated that the caves themselves predate the entrenchment of the valleys and the glaciations. During the latter the caves were filled up and emptied several times, without any modifications of their inner morphology, including stalactites. Moreover the U/Th age determinations indicate that a great number of concretions are older than 350 ky, and that a few are older than 1.5 Ma. As a conse-quence, a general model of karst evolution can be proposed. The former karstic drainage system developed after the Oligo-Miocene emersion. Paleogeography obviously diffe-red from the present day landscape but the main valley had already been scoured. During the Messinian the dramatic lowering of base level determined major changes in karstic evolution and a reorganisation of the karst drainage system that was consequently lowered considerably. The Pliocene transgression determined a new karst evolution, after which a great number of caves were located well below the sea level base. This evolution occurred during hot and wet climate period, with seasonal high flows and relevant discharges of the karstic rivers The great caves of the Lombardian karst developed within the climatic stage.

Management of some unusual features in the show caves of the United States., 1994, Gurnee Jeanne
Protection of the unusual features in some of the 200 show caves of the U.S. have required innovative management. The sea caves of both the east and west coasts present the need for special preservation methods. Throughout the nation sometimes glass enclosures, vehicles and boats are used to separate visitors from sensitive cave features. Lighting and cleaning techniques have been studied and altered to discourage growth of algae. Some show caves are protected by double glass entrance and exit doors. Many caves, particularly on public lands, are closed during the hibernation period of endangered bats. In a number of caves, Native Americans have left artifacts and other evidences of their early visits. which have either been preserved in situ or relocated at appropriate archival sites. The paper gives in more details specific caves and methods for the preservation of particular unique features.

Hydrological response of small watersheds following the Southern California Painted Cave Fire of June 1990, 1997, Keller E. A. , Valentine D. W. , Gibbs D. R. ,
Following the Painted Cave Fire of 25 June 1990 in Santa Barbara, California which burned 1214 ha, an emergency watershed protection plan was implemented consisting of stream clearing, grade stabilizers and construction of debris basins. Research was initiated focusing on hydrological response and channel morphology changes on two branches of Maria Ygnacio Creek, the main drainage of the burned area. Research results support the hypothesis that the response of small drainage basins in chaparral ecosystems to wildfire is complex and flushing of sediment by fluvial processes is more likely than by high magnitude debris flows. During the winter of 1990-1991, 35-66 cm of rainfall and intensities up to 10 cm per hour for a five-minute period were recorded with a seasonal total of 100% of average (normal) rainfall (average = 63 cm/year). During the winter of 1991-1992, 48-74 cm of rainfall and intensities up to 8 cm per hour were recorded with a seasonal total of 115% of normal. Even though there was moderate rainfall on barren, saturated soils, no major debris flows occurred in burned areas. The winter of 1992-1993 recorded total precipitation of about 170% of normal, annual average intensities were relatively low and again no debris flows were observed. The response to winter storms in the first three years following the fire was a moderate but spectacular flushing of sediment, most of which was derived from the hillslopes upstream of the debris basins. The first significant storm and stream flow of the 1990-1991 winter was transport-limited resulting in large volumes of sediment being deposited in the channel of Maria Ygnacio Creek; the second storm and stream flow was sediment-limited and the channel scoured. Debris basins trapped about 23 000 m(3), the majority coming from the storm of 17-20 March 1991. Sediment transported downstream during the three winters following the fire and not trapped in the debris basins was eventually flushed to the estuarine reaches of the creeks below the burn area, where approximately 108 000 m(3) accumulated. Changes in stream morphology following the fire were dramatic as pools filled with sediment which greatly smoothed longitudinal and cross-sectional profiles. Major changes in channel morphology occur following a fire as sediment derived from the hillslope is temporarily stored in channels within the burned area. However, this sediment may quickly move downstream of the burned region, where it may accumulate reducing channel capacity and increasing the flood hazard. Ecological consequences of wildfire to the riparian zone of streams in the chaparral environment are virtually unknown, but must be significant as the majority of sediment (particularly gravel necessary for fish and other aquatic organisms) entering the system does so in response to fires. (C) 1997 by John Wiley & Sons, Ltd

Rapport entre karst et glaciers durant les glaciations dans les valles pralpines du sud des Alpes, 1998, Bini Alfredo, Tognini Paola, Zuccoli Luisa
At least 13 glaciations occurred during the last 2.6Ma in the Southern pre_alpine valleys. The glaciers scouring alpine and pre-alpine valleys had all the same feature, being valley temperated glaciers. Their tracks and feeding areas were always the same, just like the petrological contents of their deposits. Contrary to previous assumptions until a few years ago, the origin of these valleys and of the lakes occupying the floor of some of them (Orta, Maggiore, Como, Iseo, Garda Lakes) is due to fluvial erosion related to Messinian marine regression. The valley slopes modelling is Messinian in age, too, while most caves are older. As a general rule, glaciers worked on valley slopes just as a re_modelling agent, while their effects were greater on valley floors. The karstic evolution began as soon as the area was lifted above sea level (upper Oligocene - lower Miocene), in a palaeogeographical environment quite different from the present one, although the main valley floors were already working as a base level. During Messinian age, the excavation of deep canyons along pre-existing valleys caused a dramatic lowering of the base level, followed by a complete re-arrangement of the karstic networks, which got deeper and deeper. The Pliocene marine transgression caused a new re-arrangement, the karst network getting mostly drowned under sea level. During these periods, the climate was hot-wet tropical, characterised by a great amount of water circulating during the wet season. At the same time tectonic upliftings were at work, causing breaking up of the karst networks and a continuous rearrangement of the underground drainage system. In any case, karstic networks were already well developed long before the beginning of Plio-Quaternary glaciations. During glaciations, karst systems in pre-alpine valleys could have been submitted to different drainage conditions, being: a) isolated, without any glacial water flowing; b) flooded, connected to the glacier water-filled zone; c) active, scoured by a stream sinking at glacier sides or in a sub glacial position. The stream could flow to the flooded zone (b), or scour all the unflooded system long down to the resurgence zone, the latter being generally located in a sub glacier position. The glacier/karst system is a very dynamic one: it could get active, flooded or isolated depending on endo- and sub-glacial drainage variations. Furthermore, glaciers show different influences on karstic networks, thus working with a different effect during their advance, fluctuations, covering and recession phases. Many authors believe, or believed, the development of most surface and underground karst in the Alps is due to glaciations, with the last one held to be mostly responsible for this. Whatever the role of glaciers on karstic systems, in pre-alpine valleys caves, we do not have evidence either of development of new caves or of remarkable changes in their features during glaciations. It is of course possible some pits or galleries could have developed during Plio-Quaternary glaciations, but as a general rule glaciers do not seem to have affected karstic systems in the Southern pre-alpine valleys with any remarkable speleogenetic effects: the glaciers effects on them is generally restricted to the transport of great amounts of debris and sediments into caves. The spotting of boulders and pebbles trapped between roof stalactites shows that several phases of in- and out-filling of galleries occurred with no remarkable changing in pre-dating features, including cave decorations. The presence of suspended karst systems does not prove a glacial origin of the valleys, since most of them pre-date any Plio-Quaternary glaciation, as shown by calcite cave deposits older than 1,5Ma. The sediments driven into caves might have caused a partial or total occlusion of most galleries, with a remarkable re-arrangement of the underground drainage system. In caves submitted to periglacial conditions all glaciations long, we can find deposits coming from weathered surface sediments, sharp-edged gelifraction debris and, more rarely, alluvial deposits whose origin is not related to the circulation of the glacial meltwater. In caves lower than or close to the glaciers limit we generally find large amounts of glacier-related deposits, often partly or totally occluding cave galleries. These sediments may be directly related to glaciers, i.e. carried into caves by glacial meltwaters, resulting from surface glacial deposit erosion. They generally show 3 dominant facies: A) lacustrine deposits; B) alluvial deposits and C) debris flow deposits facies. The only way of testing the soundness of the forementioned hypothesis is to study the main characters and spreading of cave sediments, since they are the only real data on connection of glaciers to endokarst networks.

Thalweg variability at bridges along a large karst river: the Suwannee River, Florida, 1998, Mossa J. , Konwinski J. ,
Geomorphologists and engineers have different perspectives and approaches for examining river channels and the changes that occur during floods. The field-oriented approach typically adopted by geomorphologists has little predictive ability and design usefulness. In contrast, the empirical approach adopted by engineers is based on predictive equations or models that often differ greatly from reality. Such equations are not based on comprehensive field data and often fail to consider a number of site conditions, especially geology and geomorphology. Yet, in order for geomorphic techniques to be useful to the design and planning of engineering structures such as bridges, it is important that sufficient observations exist in order to characterize long-term and short-term changes in bottom topography and scour potential. Six gaging stations on the Suwannee River, a large river draining karst terrain in the southeastern US, were used to examine the temporal variability in thalweg elevation, the deepest point in a given cross-section. The cross-sections have maximum thalweg variability of just a few meters, despite the occurrence of several large floods. suggesting that the bottoms are fairly stable. Historical approaches can be applied to design the length and depth placement of pilings by providing information on site conditions not considered in engineering equations, such as response of bottom materials to various flow conditions, and thus have potential benefits to public safety and cost effectiveness. (C) 1998 Elsevier Science B.V

Non-invasive investigation of polygonal karst features: Yorkshire Dales National Park. MSc thesis (Exploration Geophysics), 1999, Gullen T.

Resistivity, refraction and resistivity tomography methods were used to ascertain the dimensions of any sediment body present within solution dolines. Fieldwork was undertaken at two sites within the Yorkshire Dales National Park: High Mark [SD920 679] northeast of Malham Tarn, and on Ingleborough, northeast of Clapham Bottoms [SD765 722].
Results of previous studies of doline fill have been inconclusive. It has been hypothesised (Howard, unpublished) that if dolines do contain significant amounts of sediment, the fill could provide a complete palaeoenvironmental record of the Quaternary.
Resistivity studies undertaken at High Mark used an Offset Wenner array, and field data were inverted to produce a 1-D image of the subsurface. The profiles were located at the base of the doline, in the area believed to contain the greatest sediment thickness. Results suggest that the fill comprises two layers. An upper layer approximately 1 m thick is composed of poorly consolidated clayey sand with an apparent resistivity of 166m. The second layer reaches a depth of 5.6m and is more clay-rich, with an apparent resistivity of 60m. These interpretations are supported by evidence from augering. The upper 10m of limestone below the sediment has been altered during doline formation, weathering and fracturing, and has a resistivity of 220m compared to 440m for the unaltered bedrock.
Refraction profiles were undertaken at High Mark, using the hammer and plate method with a 2m geophone spacing. Profiles were located on the base, flanks and interfluves of the doline. Ground conditions prevented the acquisition of very long offset shots (>10m), and lack of these data hindered interpretation. Profiles undertaken at Ingleborough used an explosive shot placed in a 45cm-deep hole, and a 5m geophone spacing was used. Profiles were located at the base of the dolines.
Results at High Mark suggest that the limestone is overlain by 4m of sediment. The upper layer has a velocity of approximately 0.50m/ms, whereas that of the second layer is 1.19m/ms. Alteration of the upper 6m of the bedrock is indicated by a velocity of 2.00m/ms, compared to 2.99m/ms for the unaltered limestone. The bedrock surface is undulatory, possibly indicating the effects of preferential dissolution or glacial activity.
Results of the refraction surveys at Ingleborough indicate that the limestone is overlain by a single 4m-thick layer of sediment with a velocity of 0.52m/ms. Beneath this, the upper 13m of limestone is altered, with a velocity of 2.45m/ms, which increases to 3.75m/ms in the unaltered limestone below. Velocities obtained are lower than expected, but reliable imaging of the limestone was ensured by siting the profiles close to observed rock exposures. Refraction interpretations indicate that the centre of the doline is not coincident with the position predicted from observation of the surface morphology.
Resistivity tomography profiles were undertaken at the base of the dolines at both sites. A fully automated system employing a Wenner array with 25 electrodes at 5m spacings was used, and six levels were recorded. The field data were inverted and the results suggest that there are about 12.5m of sediment in the High Mark doline. The sediment is underlain by 2m of altered limestone and the bedrock base of the doline is relatively smooth.
In contrast, the thickness of sediment fill in the Ingleborough dolines is 7.5m, but the depressions are bounded by a greater thickness of altered limestone (10m). In places the limestone imaged appears to reach the surface, but is not observed in the field, indicating that minimal sediment cover is not imaged. The surface of the limestone is pitted by smaller sediment-filled depressions, possibly a feature of glacial scour.
Two profiles were forward modelled to test the reliability of the inversion model. The models were similar, but features were displaced to the right of the true section. Synthetic models were constructed to test geological hypotheses concerning the composition of the dolines. The models suggested that the dolines are relatively shallow (<12m) and are underlain by significant thicknesses of altered limestone (~10m).
The combination of results obtained suggests that dolines are not filled by significant quantities of sediment and, consequently, they cannot be used as palaeoenvironmental indicators of the Quaternary.
Jobling A. 2000. Resistivity tomography survey over a topographic depression, West Yorkshire.
BSc thesis (Geophysical Sciences), School of Earth Sciences, University of Leeds, Leeds, LS2 9JT, UK.
Three resistivity profiles were completed across a topographic depression near Garforth, West Yorkshire. The depression is roughly circular, with a radius of approximately 20m. Two profiles ran through the centre of the depression, with a third profile lying outside it. Data from these three profiles were processed, and graphs and pseudosections were compiled. The data were also inverted.
The pseudosections and inversions both showed a large, negative resistivity anomaly centred approximately beneath the surface depression. This anomaly had a resistivity difference of between 600m and 700m compared to that of the surrounding rock.
The most likely reason for this anomaly is dissolution of limestone causing development of a doline or sinkhole. The chance of the depression being an old coal mine or sand mine working has been dismissed due to the location of the site and the nature of the resistivity anomaly.


Le karst des Arbailles (Pyrnes-Atlantiques, France), 2000, Vanara, Nathalie
The Arbailles massif (200 - 1200 m) is located in the french north face of Pyrnes, Atlantic side. It forms a folded 165 square-kilometres unit of jurassic and cretaceous limestones under an oceanic climate of altitude (2000 mm/year). Observations jointly made on the surface and in the numerous underground galleries allow an occurate correlation of alternate surrective and karstic periods. The dismantled cavities and deposits pockets of the upper surface show two series of minerals, those from weathered marly-albian limestones and others supplied from the conglomerates pudding-stones of Mendibelza. During the Miocene, the Arbailles massif is a low area of tropical erosion on the side of the main mounts. Its surrection caused the scouring of the alterites cover, the formation of fields of karstic butts and a definitive drying of the fluviatile paleosystem. The different levels of dried valleys and the karstic hydrographic systems are successive stations of the karstic levels of origine. Paleomagnetic datations in Etxanko Zola and U/Th datations in Nbl show that the surrection has been of about 500 m since lower Pleistocene. At the present time, water collection is made through drainage systems without any connection to the fossil topography. Three aquifers can be distinguished: in lower cretaceous, in jurassic and in north and south limits. They are water-repellent because of more or less impermeable screens. Waters are aggressive in summer and at equilibrium or lightly undersaturated the rest of the year. The modern human activities create a recent destabilisation of the environment with local erosions of grounds and an increasing turbidity of springs. An occurate study in the fail of Istaurdy allows a mesure of the effect of deforestation for the whole massif.

Spatial and temporal patterns of bacterial density and metabolic activity in a karst aquifer, 2001, Simon K. S. , Gibert J. , Petitot P. , Laurent R. ,
Karst aquifers are heterotrophic ecosystems fueled by organic matter imported from the surface. The temporal pattern of floods influences organic matter import and the spatial distribution of organic matter and biofilms in aquifer structural zones. We investigated spatial and temporal patterns of bacterial density and activity as indicators of energy availability and microbial dynamics in a karst aquifer. During baseflow, bacterial density and microbial hydrolytic activity were similar in the upper and lower zones of the aquifer. Floods apparently scoured aquifer biofilms and trans ported soil bacteria into the aquifer, increasing inactive bacterial density in the water column. Respiring bacterial density did not respond to floods and changed little over time. The overall proportion of total bacteria that were respiring was very high on some dates, resulting from a reduction of inactive cell density during flood recession. Floods appear to be key events in scouring senescent microbial assemblages in karst aquifers and stimulating microbial recolonization of the aquifer matrix. We conclude that a conceptual model of karst aquifer structure and function should incorporate changes caused by alternation between flooding and drying in the aquifer

Late Quaternary intensified monsoon phases control landscape evolution in the northwest Himalaya, 2005, Bookhagen B, Thiede Rc, Strecker Mr,
The intensity of the Asian summer-monsoon circulation varies over decadal to millennial time scales and is reflected in changes in surface processes, terrestrial environments, and marine sediment records. However, the mechanisms of long-lived (2-5 k.y.) intensified monsoon phases, the related changes in precipitation distribution, and their effect on landscape evolution and sedimentation rates are not yet well understood. The arid high-elevation sectors of the orogen correspond to a climatically sensitive zone that currently receives rain only during abnormal (i.e., strengthened) monsoon seasons. Analogous to present-day rainfall anomalies, enhanced precipitation during an intensified monsoon phase is expected to have penetrated far into these geomorphic threshold regions where hillslopes are close to the angle of failure. We associate landslide triggering during intensified monsoon phases with enhanced precipitation, discharge, and sediment flux leading to an increase in pore-water pressure, lateral scouring of rivers, and oversteepening of hillslopes, eventually resulting in failure of slopes and exceptionally large mass movements. Here we use lacustrine deposits related to spatially and temporally clustered large landslides (>0.5 km3) in the Sutlej Valley region of the northwest Himalaya to calculate sedimentation rates and to infer rainfall patterns during late Pleistocene (29-24 ka) and Holocene (10-4 ka) intensified monsoon phases. Compared to present-day sediment-flux measurements, a fivefold increase in sediment-transport rates recorded by sediments in landslide-dammed lakes characterized these episodes of high climatic variability. These changes thus emphasize the pronounced imprint of millennial-scale climate change on surface processes and landscape evolution

The role of the epikarst in karst and cave hydrogeology: a review, 2008, Williams P. W.
The epikarst (also known as the subcutaneous zone) comprises highly weathered carbonate bedrock immediately beneath the surface or beneath the soil (when present) or exposed at the surface. Porosity and permeability are higher near the surface than at depth, consequently after recharge percolating rainwater is detained near the base of the epikarst, the detention ponding producing an epikarstic aquifer. Such an aquifer is found only where the uppermost part of the vadose zone is very weathered compared to the bedrock at depth. Sometimes this contrast in porosity and permeability does not occur either because the epikarst has been scraped off by glacial scour or because high porosity exists throughout the bedrock. In some conditions porosity may even diminish near the surface because of case-hardening. The epikarst is best developed in pure, crystalline limestones or marble where it is typically about 10 m thick. It then contains a suspended aquifer that is under-drained and sustains the distal tributaries of cave streams and small perennial flows emerging on hillsides (epikarstic springs). Slow leakage paths from the epikarst maintain seepage to many stalactites throughout the year. A distinction should be recognized between the location (and form) of the epikarst and the function of the epikarst, because the near surface zone in carbonate rocks does not always contain a suspended aquifer

The role of the epikarst in karst and cave hydrogeology: a review., 2008, Williams, P. W.

The epikarst (also known as the subcutaneous zone) comprises highly weathered carbonate bedrock immediately beneath the surface or beneath the soil (when present) or exposed at the surface. Porosity and permeability are higher near the surface than at depth, consequently after recharge percolating rainwater is detained near the base of the epikarst, the detention ponding producing an epikarstic aquifer. Such an aquifer is found only where the uppermost part of the vadose zone is very weathered compared to the bedrock at depth. Sometimes this contrast in porosity and permeability does not occur either because the epikarst has been scraped off by glacial scour or because high porosity exists throughout the bedrock. In some conditions porosity may even diminish near the surface because of case-hardening. The epikarst is best developed in pure, crystalline limestones or marble where it is typically about 10 m thick. It then contains a suspended aquifer that is under-drained and sustains the distal tributaries of cave streams and small perennial flows emerging on hillsides (epikarstic springs). Slow leakage paths from the epikarst maintain seepage to many stalactites throughout the year. A distinction should be recognized between the location (and form) of the epikarst and the function of the epikarst, because the near surface zone in carbonate rocks does not always contain a suspended aquifer


History of cave archaeology in Slovenia: politics, institutions, individuals, methods and theories, 2011, Prijatelj, Agni

The practice and discourse of cave archaeology in Slovenia have reflected the wider histories of cave archaeology in Europe, yet, on the other hand, also revealing local and national particularities. These have been created first by regional history, and second by the national archaeological research agenda, the institutional background and patterns of funding, as well as the few prominent researchers dominating the field. An intricate sequence of field work and publications constructed by only a few individuals over a period of 120 years is examined in this article


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