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Speleology in Kazakhstan

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

New publications on hypogene speleogenesis

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

The deepest terrestrial animal

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

Caves - landscapes without light

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

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That magnetic north is the direction to the north magnetic pole at a given place and time. this differs from the direction towards which the north end of a compass points by a small individual compass error and by the effect of any local magnetic attraction [25].?

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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.
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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 brazil. (Keyword) returned 21 results for the whole karstbase:
Showing 1 to 15 of 21
The Vazante zinc mine, Minas Gerais, Brazil; constraints in willemitic mineralization and fluid evolution, 1999, Lena Virginia Soares Monteiro, Jorge Silva Bettencourt, Baruch Spiro, Rodnei Graca, And Tolentino Flavio De Oliveira
The Vazante Mine is located in the Vazante District, the largest zinc district in Brazil. The Vazante deposit consists dominantly of an unusual willemitic ore. Small sulfide bodies are tectonically imbricated with the willemitic ore, within the Vazante shear zone. Structural styles of deformation and petrographic and isotopic evidence indicate that willemitic mineralization and deformation occurred synchronously during the Neo-Proterozoic. Various generations of hydrothermal veins and hydraulic breccias may pre-date, accompany and overprint the mineralization. Ore-formation temperatures are deduced from stable isotope geothermometry and mineral chemistry of both sulfide bodies and willemitic ore. Temperatures during the main stage of mineralization range from 206 degrees C to 294 degrees C (willemitic ore) and 317 degrees C (sulfides), and reflect the prevailing metamorphic conditions within the shear zone. The fluid from which the gangue minerals of the sulfide bodies precipitated (at 250 degrees C) had an oxygen isotopic average value of delta 18 O = +19.4 per mil. This value appears to reflect the interaction of metamorphic fluid with the carbonate rocks of the Vazante formation. At 250 degrees C, the fluid in equilibrium with the vein mineral phases and willemitic ore assemblage exhibits a uniform oxygen isotopic composition, with an average value of delta 18 O = +11.5 per mil. The positive linear covariance of delta 18 O and delta 13 C ratios of the carbonates is most likely due to the mixing of metamorphic and meteoric fluids. The delta 34 S values of sulfides indicate a direct crustal origin for the sulfur. It is suggested that the sulfur is largely derived from pre-existing sulfide bodies and has been transported by metamorphic fluids. The willemitic ore may have originated from the precipitation of metal in sulfur-poor fluids under oxidized conditions, within the Vazante shear zone.

Nordstrandite from Lages represents the first occurrence of this mineral in an oxisoil that does not involve the influence of a calcareous substrate. This is also the first reported occurrence in Brazil. Nordstrandite occurs near the city of Lages only in the weathered bedrock facies, mostly where the circulation of meteoric water is restricted. There is also a close association between nordstrandite and the weathering of modified pseudoleucite structures. The interaction of meteoric water and feldspathic alkaline country rock with uncommon texture and mineralogy (rich in nepheline, sodalite, nosean, analcime and natrolite) promotes the development of solutions enriched in alkaline ions with basic pH, necessary to form nordstrandite. A detailed study by X-ray diffraction (XRD) and infrared (IR) spectroscopy in natural or chemically leached samples was performed to identify the Al(OH)3 polymorphs of gibbsite and nordstrandite

The influence of bedrock-derived acidity in the development of surface and underground karst: Evidence from the Precambrian carbonates of semi-arid northeastern Brazil, 2003, Auler As, Smart Pl,
Very extensive cave systems are developed in Precambrian Una Group carbonates in the Campo Formoso area, eastern Brazil. In contrast, the area is largely devoid of significant surface karst landforms, as would be expected given its semi-arid climate. The caves in the area display many morphological features characteristic of deep-seated hypogenic caves, such as lack of relationship with the surface, ramiform/network pattern, abrupt variations of passage cross-sections and absence of fluvial sediments, but do not show evidence of vertical passages marking the ascending path of acidic water nor present extensive gypsum or acid clay mineral deposits. Hydrochemical analyses of present-day ground water indicate that oxidation of bedrock sulphide is an active process, and sulphuric acid may be the main agent driving carbonate dissolution in the area. A shallow mode of speleogenesis is thus proposed, in which sulphuric acid produced through the oxidation of sulphide beds within the carbonates controls cave initiation and development. Moreover, the geological situation of the area in an ancient stable passive margin precludes the possibility of deep-seated sources of acidity. Under dry climate, due to the absence of recharge, solutional landforms will be largely subdued in the surface. Hypogenic processes, if present, are likely to predominate, producing a landscape characterized by a marked disparity in the comparative degree of development between surface and underground landforms. Rates of karst landform development have traditionally been analysed through a climatic perspective, runoff being the main controlling factor in promoting karst development. This view needs to be reassessed in the light of the growing awareness of the importance of climate-independent processes related to hypogenic sources of acidity.

Rates of condensation corrosion in speleothems of semi-arid northeastern Brazil, 2004, Auler A. S. , Smart P. L.

Condensation corrosion is a little studied, but important dissolutional process that occurs within caves in many karst settings around the world (for a review see Dublyansky and Dublyansky, 2000). Condensation corrosion occurs when air equilibrates with the cave atmosphere, becomes acidic and dissolves the bedrock and speleothems. It is a later vadose process that apparently depends on air circulation patterns, number of entrances and general configuration (vertical range, presence of ponded water, passage shape, etc) of the cave. Both bedrock and speleothems can be affected by the process, resulting in weathered outer surfaces. Condensation corrosion in speleogenesis has been regarded as responsible for dissolutional modification during later stages of cave development of coastal (Tarhule-Lips and Ford, 1998) and hypogenic caves (Hill, 1987; Palmer and Palmer, 2000).
Condensation corrosion is a little studied, but important dissolutional process that occurs within caves in many karst settings around the world (for a review see Dublyansky and Dublyansky, 2000). Condensation corrosion occurs when air equilibrates with the cave atmosphere, becomes acidic and dissolves the bedrock and speleothems. It is a later vadose process that apparently depends on air circulation patterns, number of entrances and general configuration (vertical range, presence of ponded water, passage shape, etc) of the cave. Both bedrock and speleothems can be affected by the process, resulting in weathered outer surfaces. Condensation corrosion in speleogenesis has been regarded as responsible for dissolutional modification during later stages of cave development of coastal (Tarhule-Lips and Ford, 1998) and hypogenic caves (Hill, 1987; Palmer and Palmer, 2000).
The Campo Formoso Karst area of northeastern Brazil holds very extensive cave systems, such as Southern Hemisphere’s longest cave, the 97 km long Toca da Boa Vista. These caves show remarkable features of condensation corrosion such as cupolas, weathered cave walls yielding dolomitic sand, “air scallops” and corroded speleothems. Weathering rinds up to 5 cm thick occur in both dolomite bedrock and speleothem surfaces. Unlike the dolomite, speleothems usually do not disintegrate but change to a milky white opaque porous calcite that is in marked contrast with the fresh crystalline calcite. The area is presently under semi-arid climate and the cave atmosphere is characterised by high internal temperatures (2729 °C) and low relative humidity (mean of 73% for sites away from entrances).
Despite being such a widespread process, rates of condensation corrosion have so far been reported only from caves in the coastal area of the Caribbean (Tarhule-Lips and Ford, 1998). In this study, rates of condensation corrosion in speleothems were derived by determining thickness of weathering rind and age of last unaltered calcite. These rates represent minimum rates because speleothem growth ceased later than age obtained, and also condensation corrosion may not be continuous in time. Due to variable thickness of weathering layer (usually thicker at the top and thinner at sides of stalagmites), maximum and minimum thickness were obtained for each sample. Dating was performed through the alpha spectrometric U-series method in the first unaltered calcite layer beyond the weathering rim. 
The rates obtained vary over two orders of magnitude. They appear to be highly site specific, and are probably heavily dependent on the local atmospheric conditions, although more sampling is needed to confirm this relationship. The data shows that rates are dependent primarily on thickness measured, as range of ages is quite small. Tarhule-Lips and Ford (1998), in the very different littoral caves of the Caribbean, have estimated condensation corrosion rates based on experiments using gypsum tablets. Their reported mean value of 24 mm/ka, much higher than observed in the Campo Formoso caves, suggest that the process may be episodic in the area, not occurring during speleothem growth phases associated with wetter periods.
Although the rates reported by Tarhule-Lips and Ford (1998) indicate that condensation corrosion may actually enlarge cave passages in the normal (10 4 – 10 6 ka) time range of speleogenesis, in the Campo Formoso caves the process appears to play a minor speleogenetic role, being responsible for later modification of cave walls and speleothems.

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

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

Stable isotope study of cave percolation waters in subtropical Brazil: Implications for paleoclimate inferences from speleothems, 2005, Cruz Fw, Karmann I, Viana O, Burns Sj, Ferrari Ja, Vuille M, Sial An, Moreira Mz,
We analyze the interannual monthly variability of oxygen isotope ratios in data from IAEA stations along the Atlantic coast of South America between 23 degrees and 34 degrees S to evaluate the influence of parameters such as temperature, rainfall amount and moisture source contribution on meteoric water recharging two karst systems in subtropical Brazil. In addition, a 2 year monitoring program performed on soil and cave drip and rimstone pool waters from sampling sites with contrasting discharge values and located at 100 and 300 m below the surface in the Santana Cave System (24 degrees 31' S; 48 degrees 43' W), is used to test the influence of hydrologic and geologic features on the temporal variations of seepage water delta(18)O. Interannual monthly variations in delta(18)O of rainfall reflect primarily regional changes in moisture source contribution related to seasonal shifts in atmospheric circulation from a more monsoonal regime in summer (negative values of delta(18)O) to a more extratropical regime in winter (positive values of delta(18)O). Variations in groundwater delta(18)O indicate that the climatic signal of recent rainfall events is rapidly transmitted through the relatively deep karst aquifer to the cave drip waters, regardless of location of collection in the cave. In addition, the data also suggest that water replenishment in the system is triggered by the increase in hydraulic head during periods when recharge exceeds the storage capacity of the soil and epikarst reservoirs. Significant perturbations in the groundwater composition, characterized by more positive values of delta(18)O, are probably connected to an increased Atlantic moisture contribution associated with extratropical precipitation. This implies that the delta(18)O of speleothems from caves in this region may be a suitable proxy for studying tropical-extratropical interactions over South America, a feature that is intrinsically related to the global atmospheric circulation. (c) 2005 Elsevier B.V. All rights reserved

Geomorphology and geospeleology of the Serra da Bodoquena karst, Mato Grosso do Sul, Brazil. PhD thesis , 2005, Sallun Filho, W.

The Bodoquena plateau, developed over the Corumbá Group (Neoproterozoic III – Paraguai Fold Belt), is a carbonate rock highland relative to the non carbonate lowlands of the Mato Grosso do Sul State, mid-western Brazil.
Based on 1:60.000 scale morphological analysis of the karst topography, three main compartments were defined. The first one is a mixed recharge karst system (mainly autogenic), dominated by labyrinth and polygonal karst landforms, developed over limestone of the Bodoquena plateau. The second unit is characterized by essentially autogenic recharge, residual hills and karstic plains with dolines, developed mainly over dolomites of the Miranda river depression (lowlands). The third one, characterizes an interestratal karst system in proterozoic limestones overlain by sandstones of the Aquidauana Formation of the phanerozoic Paraná basin. This geomorphological unit is localized at the southern extremity of the Bodoquena plateau, exhibiting flat topography, with frequent dolines in sandstone, of up to 700 m in diameter.
Although the Bodoquena karst system is well developed, as can be inferred based on the presence of several vauclusian springs, blind valleys in the northwest border, dolines and a deep conduit aquifer evidenced through productive water wells, the cave incidence is low as are their dimensions, considering the large carbonate rock exposure. Four cave patterns were recognized, which are related to the above geomorhological units: 1) large irregular breakdown halls in plan view and dipping planes in longitudinal section (following bedding and joint surfaces), which frequently reach up to 90 m beneath the water table, sometimes with large lakes, as for example, the Lago Azul cave (Bonito municipality). This pattern is the most frequent cave type of the second unit, occurring at the dolomitic residual hills with karst plains; 2) network caves with anastomotic pattern in plan view and circular to elliptical conduits with lateral anastomosis in cross section. They occur mostly associated with the labyrinth and polygonal karst topography of the first morphological unit and rarely with the unit of residual hills and plains; 3) caves with meandering conduits in plan view, sometimes with active or inactive allogenic stream sinks, associated with the polygonal and labyrinth karst topography; 4) Steep dipping phreatic conduits, characterizing vauclusian springs, occurring at the limestone plain along the base of the eastern escarpment of the Bodoquena plateau.
The recent tectonic activity along the Bodoquena plateau area was detected by the following features: vadose speleothems submerged at least 16 m beneath the lowest seasonal water level stage; limestone highland with escarpment beside dolomitic lowlands; northern part of the carbonate plateau with deep entrenched river valleys in contrast with the southern sector of open valleys and less entrenchment; linear structure observed in 1:250.000 scale which marks the border of the Pantanal basin and crosses the Bodoquena plateau.

2D and 3D GPR imaging of sinkholes and dissolution features in Jandaíra karst of Fazenda Belém oil field, Potiguar Basin-CE, northeast of Brazil, PhD Thesis, 2005, Xavier Neto, Pedro

In Fazenda Belém oil field (Potiguar Basin, Ceará State, northeast Brazil) occur frequently sinkholes and sudden terrain collapses associated to an unconsolidated sedimentary cap covering the Jandaíra karst. This research was carried out in order to understand the mechanisms of generation of these collapses. The main tool used was Ground Penetrating Radar (GPR). This work is developed twofold: one aspect concerns methodology improvements in GPR data processing whilst another aspect concerns the geological study of the Jandaíra karst. This second aspect was strongly supported both by the analysis of outcropping karst structures (in another regions of Potiguar Basin) and by the interpretation of radargrams from the subsurface karst in Fazenda Belém.

It was designed and tested an adequate flux to process GPR data which was adapted from an usual flux to process seismic data. The changes were introduced to take into account important differences between GPR and Reflection Seismic methods, in particular: poor coupling between source and ground, mixed phase of the wavelet, low signal-to-noise ratio, monochannel acquisition, and high influence of wave propagation effects, notably dispersion. High frequency components of the GPR pulse suffer more pronounced effects of attenuation than low frequency components resulting in resolution losses in radargrams. In Fazenda Belém, there is a stronger need of an suitable flux to process GPR data because both the presence of a very high level of aerial events and the complexity of the imaged subsurface karst structures. The key point of the processing flux was an improvement in the correction of the attenuation effects on the GPR pulse based on their influence on the amplitude and phase spectra of GPR signals. In low and moderate losses dielectric media the propagated signal suffers significant changes only in its amplitude spectrum; that is, the phase spectrum of the propagated signal remains practically unaltered for the usual travel time ranges. Based on this fact, it is shown using real data that the judicious application of the well known tools of time gain and spectral balancing can efficiently correct the attenuation effects. The proposed approach can be applied in heterogeneous media and it does not require the precise knowledge of the attenuation parameters of the media. As an additional benefit, the judicious application of spectral balancing promotes a partial deconvolution of the data without changing its phase. In other words, the spectral balancing acts in a similar way to a zero phase deconvolution. In GPR data the resolution increase obtained with spectral balancing is greater than those obtained with spike and predictive deconvolutions.

The evolution of the Jandaíra karst in Potiguar Basin is associated to at least three events of subaerial exposition of the carbonatic plataform during the Turonian, Santonian, and Campanian. In Fazenda Belém region, during the mid Miocene, the Jandaíra karst was covered by continental siliciclastic sediments. These sediments partially filled the void space associated to the dissolution structures and fractures. Therefore, the development of the karst in this region was attenuated in comparison to other places in Potiguar Basin where this karst is exposed. In Fazenda Belém, the generation of sinkholes and terrain collapses are controlled mainly by: (i) the presence of an unconsolidated sedimentary cap which is thick enough to cover completely the karst but with sediment volume lower than the available space associated to the dissolution structures in the karst; (ii) the existence of important structural of SW-NE and NW-SE alignments which promote a localized increase in the hydraulic connectivity allowing the channeling of underground water, thus facilitating the carbonatic dissolution; and (iii) the existence of a hydraulic barrier to the groundwater flow, associated to the Açu-4 Unity.

The terrain collapse mechanisms in Fazenda Belém occur according to the following temporal evolution. The meteoric water infiltrates through the unconsolidated sedimentary cap and promotes its remobilization to the void space associated with the dissolution structures in Jandaíra Formation. This remobilization is initiated at the base of the sedimentary cap where the flow increases its abrasion due to a change from laminar to turbulent flow regime when the underground water flow reaches the open karst structures. The remobilized sediments progressively fill from bottom to top the void karst space. So, the void space is continuously migrated upwards ultimately reaching the surface and causing the sudden observed terrain collapses. This phenomenon is particularly active during the raining season, when the water table – that normally is located in the karst – may be temporarily located in the unconsolidated sedimentary cap.

Poldi Fuhrich (1898-1926): female pioneer of severe cave exploration., 2006, Shaw, Trevor.
Poldi Fuhrich (1898-1926) of Salzburg became one of the leading cave explorers of the 1920s, a remarkable achievement for a woman at that time. Each year from 1919 to 1925 she was in the front line of new exploration in Austria's Eisriesenwelt. In 1925 she was one of the surveyors in the Poulnagollum river cave in Ireland, and she also visited caves in France, Germany, Moravia, Dalmatia, Slovenia and Brazil. Her unpublished documents and photographs from 1921, when she was working deep in kocjanske jame, reveal much about Robert Oedl's surveying methods and about their Slovene assistants. At the age of 28 she died in a cave accident while exploring the Lurgrotte in Austria.

Sedimentary manganese metallogenesis in response to the evolution of the Earth system, 2006, Roy Supriya,
The concentration of manganese in solution and its precipitation in inorganic systems are primarily redox-controlled, guided by several Earth processes most of which were tectonically induced. The Early Archean atmosphere-hydrosphere system was extremely O2-deficient. Thus, the very high mantle heat flux producing superplumes, severe outgassing and high-temperature hydrothermal activity introduced substantial Mn2 in anoxic oceans but prevented its precipitation. During the Late Archean, centered at ca. 2.75[no-break space]Ga, the introduction of Photosystem II and decrease of the oxygen sinks led to a limited buildup of surface O2-content locally, initiating modest deposition of manganese in shallow basin-margin oxygenated niches (e.g., deposits in India and Brazil). Rapid burial of organic matter, decline of reduced gases from a progressively oxygenated mantle and a net increase in photosynthetic oxygen marked the Archean-Proterozoic transition. Concurrently, a massive drawdown of atmospheric CO2 owing to increased weathering rates on the tectonically expanded freeboard of the assembled supercontinents caused Paleoproterozoic glaciations (2.45-2.22[no-break space]Ga). The spectacular sedimentary manganese deposits (at ca. 2.4[no-break space]Ga) of Transvaal Supergroup, South Africa, were formed by oxidation of hydrothermally derived Mn2 transferred from a stratified ocean to the continental shelf by transgression. Episodes of increased burial rate of organic matter during ca. 2.4 and 2.06[no-break space]Ga are correlatable to ocean stratification and further rise of oxygen in the atmosphere. Black shale-hosted Mn carbonate deposits in the Birimian sequence (ca. 2.3-2.0[no-break space]Ga), West Africa, its equivalents in South America and those in the Francevillian sequence (ca. 2.2-2.1[no-break space]Ga), Gabon are correlatable to this period. Tectonically forced doming-up, attenuation and substantial increase in freeboard areas prompted increased silicate weathering and atmospheric CO2 drawdown causing glaciation on the Neoproterozoic Rodinia supercontinent. Tectonic rifting and mantle outgassing led to deglaciation. Dissolved Mn2 and Fe2 concentrated earlier in highly saline stagnant seawater below the ice cover were exported to shallow shelves by transgression during deglaciation. During the Sturtian glacial-interglacial event (ca. 750-700[no-break space]Ma), interstratified Mn oxide and BIF deposits of Damara sequence, Namibia, was formed. The Varangian ([identical to] Marinoan; ca. 600[no-break space]Ma) cryogenic event produced Mn oxide and BIF deposits at Urucum, Jacadigo Group, Brazil. The Datangpo interglacial sequence, South China (Liantuo-Nantuo [identical to] Varangian event) contains black shale-hosted Mn carbonate deposits. The Early Paleozoic witnessed several glacioeustatic sea level changes producing small Mn carbonate deposits of Tiantaishan (Early Cambrian) and Taojiang (Mid-Ordovician) in black shale sequences, China, and the major Mn oxide-carbonate deposits of Karadzhal-type, Central Kazakhstan (Late Devonian). The Mesozoic period of intense plate movements and volcanism produced greenhouse climate and stratified oceans. During the Early Jurassic OAE, organic-rich sediments host many Mn carbonate deposits in Europe (e.g., Urkut, Hungary) in black shale sequences. The Late Jurassic giant Mn Carbonate deposit at Molango, Mexico, was also genetically related to sea level change. Mn carbonates were always derived from Mn oxyhydroxides during early diagenesis. Large Mn oxide deposits of Cretaceous age at Groote Eylandt, Australia and Imini-Tasdremt, Morocco, were also formed during transgression-regression in greenhouse climate. The Early Oligocene giant Mn oxide-carbonate deposit of Chiatura (Georgia) and Nikopol (Ukraine) were developed in a similar situation. Thereafter, manganese sedimentation was entirely shifted to the deep seafloor and since ca. 15[no-break space]Ma B.P. was climatically controlled (glaciation-deglaciation) assisted by oxygenated polar bottom currents (AABW, NADW). The changes in climate and the sea level were mainly tectonically forced

U-series dating and taphonomy of Quaternary vertebrates from Brazilian caves, 2006, Auler As, Pilo Lb, Smart Pl, Wang X, Hoffmann D, Richards Da, Edwards Rl, Neves Wa, Cheng H,
The geochronology and taphonomy of internationally important fossil bearing cave deposits were studied, both in the semi-arid Northern Bahia area and the subtropical southeastern Lagoa Santa area of Brazil. Taphonomic analysis suggests that the processes responsible for bone accumulation in the Brazilian caves vary between sites, and taphonomic bias can therefore be significant in causing differences in faunal composition. In the Toca da Boa Vista caves the presence of single articulated skeletons, and the entrance-related distribution indicate that random penetration of animals is the main mechanism of fossil accumulation, a process that biases the assemblage to smaller species, and takes place over extended time periods. In nearby Toca dos Ossos cave transport by runoff in the cave river is predominant, and biases the fauna remains to larger more robust bones and species. Deposition probably also occurred only at times of enhanced runoff giving a more contemporaneous assemblage. Similar processes were responsible for emplacement of the copious fossil remains in the more humid Lagoa Santa area, where terrigenous fossil deposits are found intercalated by massive speleothem calcite layers. In this area runoff under a drier climate probably accounts for the sediment emplacement inside caves. In both areas the mode of emplacement implies bias in the fossil record, resulting in fossil assemblages that do not mirror surface faunas, limiting palaeoenvironmental reconstruction.Mass spectrometric U-series analysis of speleothem calcite overlaying fossil remains gives minimum ages for fossil deposition. These ages confirm the previous view that many of the deposits derive from the late glacial, but also show that much older material (some > 350,000[no-break space]yr) is also present. The habitat requirements of critical fossil species such as bats and monkeys strongly suggest that they derive from much wetter periods when forest cover was present in the currently semi-arid Northern Bahia area. Taphonomy exerts a major control on the diversity and mode of emplacement of cave fossil deposits in eastern Brazil and thus detailed sedimentological and hydrological studies coupled with a sound geochronological approach are essential in quantifying the relative importance of each taphonomic processes before faunal and palaeoecological interpretations can be attempted

Geomorphological map of the Serra da Bodoquena karst, west-central Brazil, 2007, Sallun Filho, W. And Karmann, I.
The Serra da Bodoquena is a karst area situated on the southern edge of the Pantanal wetland region in the states of Mato Grosso and Mato Grosso do Sul, central-western Brazil. Morphological analysis, on a scale of 1:60,000, made it possible to identify such various karst features as dolines, caves, sinks and springs, as well as karst cones and corridors, among others, compartmentalized into six morphological units. To the west of the Serra, the labyrinth karst that was identified reflects a situation of extreme flattening and diffuse infiltration via vertical fractures, which is gradually limited by polygonal karst, to the extent that there is drawdown of the water level. To the north of the Serra, these features are obscured by a greater degree of fluvial incision, which develops in the form of canyons and alluvial plains. To the east, there is a predominance of karst plains with dolines in a thick soil covering, associated with residual hills. There are tufa deposits along the current fluvial drainage system, and extensive older deposits occur in Quaternary terraces. Sandstone plains with innumerable dolines occur to the southeast of the Serra, reflecting the presence of subjacent karst. Geomorphological mapping of this area will be able to contribute to the Serra da Bodoquena National Park management plan, or assist in the development of anthropic soil use/occupation plans.


The aim of this work is to recover some methodological aspects of the study about the mind representations of caves in Brazil. The basis of this research consisted of one essay, approaching the social representations of a particular group of high school students on the exokarst and the endokarst. The results showed that the meanings vary only slightly, however, the most inter­esting result was due to the fact that students, who had already visited caves in some period of their lives, still held “negative” concepts regarding this environment even before visual stimu­lations. About 640 words associated with the exokarst and the endokarst were mentioned, emphasizing: fear, dark, shadowy, skull, hidden places, fantastic and beauty, which helped iden­tifying relations between the cultural and psychological as­pects of the group, mainly general views about the obscure and mysterious aspects of this landscape and its prominence over natural beauties. Analyzed data showed that the development of new research on mind representations of caves is very impor­tant, mainly for environmental education programs promoting adequate concepts about caves and extending activities of edu­cational ecotourism in Brazilian caves.

The pilgrimage in Bom Jesus da Lapa (Bahia, Brazil) and its importance for the geotourism in northeast region of Brazil, 2008, Travassos L. E. P, Milagres F. C. , Barbosa F. M. Da C. P. , Varela I. D.
Men are, by nature, beings who produce sociable interactions with other beings. Human beings are individuals who posses a collective nature and obviously, the necessity of exchanging their individual knowledge with other individuals when reveal their experiences (Berguer and Luckmann, 1983). In this process, the individual spreads symbolically what he has lived while he projects a reality with its own manner of conceiving the world, through signs and retrospective meanings. In this way, the interpretation changes their own experience, delegated by the cognitive processes ? responsible for the knowledge, the conscience and the experience processing, of the perception and the memory. So we can identify the Sanctuary of ?Bom Jesus da Lapa (BA)?, as an example of the oldest ones (1691) regarding the religious usage of caverns, as well as an attraction of geotourism. Taking into consideration the deep anthropological surveys of Steil (1996; 2003), the authors identified the Sanctuary ?da Lapa (Montecillo del Buen Jesús)? as a tourist attraction for the Northeast of Brazil. There are almost 10 caves, all around the main one, the ?Gruta do Bom Jesus - la Cueva del Buen Jesús?. Due to Steil (2003), although we find that tourist ideal among a lot of pilgrims who visit the Sanctuary, the dwellers and the clergy incorporate more specifically, in different points of views. For the dwellers, ?Lapa ? la Gruta ?? is a tourist site for leisure and with profit benefits and for the clergy ?the election between the ideals of the pilgrimage and the tourists is extremely conflictive? (Steil, 2003, p. 253), in which you can identify the fight for both legacies left by the Sanctuary founder monks: the spiritual and the material. As a geotourist attraction, a lot of ?pilgrims-tourists? (Steil, 2003) declared to travel lots of km. so as to show their faith to a geological monument. Of course, when we are talking about religious tourism, we are in front of two important aspects: the leisure without compromise with rituals, and the leisure with identity and faith value. Besides, there is the fact that such tourist model has its dynamic linked to an image matter, joined to socioeconomic factors and environmental which are very important for the tourist attraction and new business development opportunities (Silveira, 2004). So, in this kind of cities with religious tourism ? like Bom Jesus da Lapa ?, people should participate of the party organizations, or assume the diversity of impact caused by this activities.

Poldi Fuhrich (1898-1926) - Pionierin der extremen Hhlenforschung, 2008, Shaw, T.
Poldi Fuhrich (1898-1926) of Salzburg became one of the leading cave explorers of the 1920s, a remarkable achievement for a woman at that time. Each year from 1919 to 1925 she was in the front line of new exploration in Austrias Eisriesenwelt. In 1925 she was one of the surveyors in the Poulnagollum river cave in Ireland, and she also visitied caves in France, Germany, Moravia, Dalmatia, Slovenia and Brazil. Her unpublished documents and photographs from 1921, when she was working deep in kocjanske jame, reveal much about Robert Oedls surveying methods and about their Slovene assistants. At the age of 28 she died in a cave accident while exploring the Lurgrotte in Austria

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