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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 hydraulic head is the height above a datum plane (such as sea level) of the column of water that can be supported by the hydraulic pressure at a given-point in a ground-water system. for a well, the hydraulic head is equal. to the distance between the water level in the well and the datum plane [22].?

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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 extraction (Keyword) returned 30 results for the whole karstbase:
Showing 16 to 30 of 30
Palaeo-climate reconstruction from stable isotope variations in speleothems: a review, 2004, Mcdermott, F.

Speleothems are now regarded as valuable archives of climatic conditions on the continents, offering a number of advantages relative to other continental climate proxy recorders such as lake sediments and peat cores. They are ideal materials for precise U-series dating, yielding ages in calendar years, thereby circumventing the radiocarbon calibration problems associated with most other continental records. Stable isotope studies in speleothems have shifted away from attempting to provide palaeo-temperature reconstructions to the attainable goal of providing precise estimates for the timing and duration of major O isotope-defined climatic events characterised by high signal to noise ratios (e.g. glacial/interglacial transitions, Dansgaard–Oeschger oscillations, the ‘8200- year’ event). Unlike the marine records, speleothem data sets are not ‘tuned’, and their independent chronology offers opportunities to critically assess leads and lags in the climate system, that in turn can provide important insights into forcing and feedback mechanisms. Improved procedures for the extraction and measurement of stable isotope ratios in fluid inclusions trapped in speleothems are likely to provide, in the near future, a much enhanced basis for the quantitative interpretation of O isotope ratios in speleothem calcite. The latter developments open up once again the tantalising prospect of palaeo-temperature estimates, but more importantly perhaps, provide a direct test for a new generation of general circulation models whose hydrological cycles will incorporate the ‘water isotopes’. The literature is reviewed briefly to provide for the reader a sense of the current state-of-the-art, and to provide some pointers for future research directions


Der Naturzustand der sterreichischen Hhlen - Vollerhebung in den Testgebieten Hochtor, Brgeralpe und Anninger., 2005, Herrmann, E.
The first part of a study concerning the status of naturalness (virginity) of Austrian caves comprises overall statistics of three cave regions in Styria and Lower Austria differing in geomorphology and land use. Except in high alpine areas nearly no cave was kept free of human influence if not transformation. Regarding the different motives, the influence of tourism is widespread but never destructive to caves while extraction of raw materials especially in quarries damaged a considerable part of all registered caves. Other cave uses are only of historic interest (like housing, defence) or were never of great importance (like traffic). This paper demonstrates that each karst region shows the effects of its specific human stress on caves. Unfortunately those caves held most important as well as those with large entrances are at the same time most endangered regarding all important aspects: their morphological integrity, their ecological functionality and their aesthetic attractiveness. The rather uniform legislation of cave protection that we have at present is quite unsuitable to guard against the manifold threats caves are facing today. So there is an urgent need for much more diversified strategies and provisions to conserve at least a few remarkable caves in their originality.[Vollerhebung von 120 Hhlen zeigt erhebliche Differenzen im Ausma der menschlichen Einflussnahme auf den unterirdischen Naturraum; Auswertung nach Eingriffsursachen, Hufigkeit der Eingriffe, Eingriffscharakteristik und Regenerierbarkeit auch im Hinblick auf Lage und Erreichbarkeit der Eingnge]

Non-stationary spatiotemporal analysis of karst water levels, 2005, Dryden Il, Markus L, Taylor Cc, Kovacs J,
We consider non-stationary spatiotemporal modelling in an investigation into karst water levels in western Hungary. A strong feature of the data set is the extraction of large amounts of water from mines, which caused the water levels to reduce until about 1990 when the mining ceased, and then the levels increased quickly. We discuss some traditional hydrogeological models which might be considered to be appropriate for this situation, and various alternative stochastic models. In particular, a separable space-time covariance model is proposed which is then deformed in time to account for the non-stationary nature of the lagged correlations between sites. Suitable covariance functions are investigated and then the models are fitted by using weighted least squares and cross-validation. Forecasting and prediction are carried out by using spatiotemporal kriging. We assess the performance of the method with one-step-ahead forecasting and make comparisons with naive estimators. We also consider spatiotemporal prediction at a set of new sites. The new model performs favourably compared with the deterministic model and the naive estimators, and the deformation by time shifting is worthwhile

Der Naturzustand der sterreichischen Hhlen - Vollerhebung in den Testgebieten Hochtor, Brgeralpe und Anninger, 2005, Herrmann, E.
The first part of a study concerning the status of naturalness (virginity) of Austrian caves comprises overall statistics of three cave regions in Styria and Lower Austria differing in geomorphology and land use. Except in high alpine areas nearly no cave was kept free of human influence if not transformation. Regarding the different motives, the influence of tourism is widespread but never destructive to caves while extraction of raw materials especially in quarries damaged a considerable part of all registered caves. Other cave uses are only of historic interest (like housing, defence) or were never of great importance (like traffic). This paper demonstrates that each karst region shows the effects of its specific human stress on caves. Unfortunately those caves held most important as well as those with large entrances are at the same time most endangered regarding all important aspects: their morphological integrity, their ecological functionality and their aesthetic attractiveness. The rather uniform legislation of cave protection that we have at present is quite unsuitable to guard against the manifold threats caves are facing today. So there is an urgent need for much more diversified strategies and provisions to conserve at least a few remarkable caves in their originality.

Characteristic odors of Tadarida brasiliensis mexicana Chiroptera: Molossidae., 2006, Nielsen L. T. , Eaton D. K. , Wright D. W. , Schmidtfrench B.
The odors in a central Texas cave with a large roosting population of Mexican free-tailed bats (Tadarida brasiliensis mexicana) were identified and related to captive individual bats. Solid phase microextraction (SPME) was used to sample and concentrate the volatile organics from the cave and individual bats. Odors were detected organoleptically and simultaneously quantified and identified. The characteristic odor for 1. b. mexicana is due principally to 2'-aminoacetophenone.

Sinkhole 'swarms' along the Dead Sea coast: Reflection of disturbance of lake and adjacent groundwater systems, 2006, Yechieli Yoseph, Abelson Meir, Bein Amos, Crouvi Onn, Shtivelman Vladimir,
More than a thousand sinkholes have developed along the western coast of the Dead Sea since the early 1980s, more than 75% of them since 1997, all occurring within a narrow strip 60 km long and <1 km wide. This highly dynamic sinkhole development has accelerated in recent years to a rate of [~]150-200 sinkholes per year. The sinkholes cluster mostly over specific sites up to 1000 m long and 200 m wide, which spread parallel to the general direction of the fault system associated with the Dead Sea Transform. Research employing borehole and geophysical tools reveals that the sinkhole formation results from the dissolution of an [~]10,000-yr-old salt layer buried at a depth of 20-70 m below the surface. The salt dissolution by groundwater is evidenced by direct observations in test boreholes; these observations include large cavities within the salt layer and groundwater within the confined subaquifer beneath the salt layer that is undersaturated with respect to halite. Moreover, the groundwater brine within the salt layer exhibits geochemical evidence for actual salt dissolution (Na/Cl = 0.5-0.6 compared to Na/Cl = 0.25 in the Dead Sea brine). The groundwater heads below the salt layer have the potential for upward cross-layer flow, and the water is actually invading the salt layer, apparently along cracks and active faults. The abrupt appearance of the sinkholes, and their accelerated expansion thereafter, reflects a change in the groundwater regime around the shrinking lake and the extreme solubility of halite in water. The eastward retreat of the shoreline and the declining sea level cause an eastward migration of the fresh-saline water interface. As a result the salt layer, which originally was saturated with Dead Sea water over its entire spread, is gradually being invaded by fresh groundwater at its western boundary, which mixes and displaces the original Dead Sea brine. Accordingly, the location of the western boundary of the salt layer, which dates back to the shrinkage of the former Lake Lisan and its transition to the current Dead Sea, constrains the sinkhole distribution to a narrow strip along the Dead Sea coast. The entire phenomenon can be described as a hydrological chain reaction; it starts by intensive extraction of fresh water upstream of the Dead Sea, continues with the eastward retreat of the lake shoreline, which in turn modifies the groundwater regime, finally triggering the formation of sinkholes

RESULTS OF PALEOSTOMATOLOGICAL ANALYSIS OF MATERIAL FROM THE CAVE NEAR GORNJI VAKUF (SOUTH-WEST BOSNIA), 2007, Zukanović, A. , Mulaomerović, J. , Marjanović, D.

Among explored speleological objects near the Krupa village, close to Gornji Vakuf, the most interesting cave from paleocultural aspect, is the cave named “Cave number 5”. In the internal part of that cave, besides ceramic fragments and one metal needle, rich anthropological material have been found, compounds of numerous humans bones and teeth. Anato-morphological analysis of the one part of material showed that this site is a prehistoric crypt with remains of at least 13 people. Radiocarbon 14C bone analysiss results showed that those people lived 2765 ± 75 before presence. The fact that anthropological material includes some remains which belonged to children shows some characteristics of burial culture of that period on area of Uskoplje. This cave crypt is the one of the biggest on this region. Paleostomatological analysis of teeth and jaw fragments gave us clear evidence about therapeutic interventions performed in this period. X-rays analysis showed presence of the metal body inside the bone in one mandibular fragment. It’s supposed that this metal is broken part of instrument used for tooth extraction.


A Review of the biospeleology of Meghalaya, India, 2008, Harries D. B. , Ware F. J. , Fischer C. W. , Biswas J. , And Kharprandaly B. D.
This paper reviews the current state of knowledge of the biospeleology of the northeast Indian hill state Meghalaya. Since the early 1990s the Meghalayan Adven- turers Association (based in Shillong), in partnership with European speleologists, has conducted a series of projects with the objective of mapping and documenting caves. To date over 320 km of cave passage have been mapped and much more remains to be discovered. The quantity and length of caves in Meghalaya exceeds that of any other known karst region of India. An exhaustive search of historical records yielded one highly detailed biological survey of a single cave in the west of the state and a few records of opportunistic specimen collection from caves at other locations. This data is supplemented by a review of numerous biological observations made during the Meghalayan Adventurers Association cave mapping program. Taxa with pronounced troglomorphic characteristics appear to be relatively common in the Jaintia Hills region of eastern Meghalaya and rare elsewhere in the state. In contrast, taxa with partial troglomorphy are widespread throughout Meghalaya. There is a range of taxa which occur regularly within caves and should be considered as significant components of the cave ecosystem regardless of troglomorphy. In some cases there is evidenceof reproductive activity and opportunity for feeding which indicates that a proportion of the population complete their lifecycle within the caves and can be regarded as troglophiles. Sources of nutrition are primarily composed of flood borne debris, although dense colonies of bats (or cave-nesting swiftlets at some sites) can also contribute. The composition of cavernicole communities is not constant throughout the region and varies due to environmental and geographic factors. A major expansion of the limestone extraction industry is underway in the Jaintia Hills and elsewhere in Meghalaya. This will inevitably cause significant destruction and perturbation of cavernicole habitat. It would be prudent to implement formal studies to document the biospeleology of the region before significant loss or damage occurs.

A REVIEW OF THE BIOSPELEOLOGY OF MEGHALAYA, INDIA, 2008, D. B. Harries, F. J. Ware, C. W. Fischer, J. Biswas, And B. D. Kharprandaly

This paper reviews the current state of knowledge of the biospeleology of the northeast Indian hill state Meghalaya. Since the early 1990s the Meghalayan Adventurers Association (based in Shillong), in partnership with European speleologists, has conducted a series of projects with the objective of mapping and documenting caves. To date over 320 km of cave passage have been mapped and much more remains to be discovered. The quantity and length of caves in Meghalaya exceeds that of any other known karst region of India. An exhaustive search of historical records yielded one highly detailed biological survey of a single cave in the west of the state and a few records of opportunistic specimen collection from caves at other locations. This data is supplemented by a review of numerous biological observations made during the Meghalayan Adventurers Association cave mapping program. Taxa with pronounced troglomorphic characteristics appear to be relatively common in the Jaintia Hills region of eastern Meghalaya and rare elsewhere in the state. In contrast, taxa with partial troglomorphy are widespread throughout Meghalaya. There is a range of taxa which occur regularly within caves and should be considered as significant components of the cave ecosystem regardless of troglomorphy. In some cases there is evidence of reproductive activity and opportunity for feeding which indicates that a proportion of the population complete their lifecycle within the caves and can be regarded as troglophiles. Sources of nutrition are primarily composed of flood borne debris, although dense colonies of bats (or cave-nesting swiftlets at some sites) can also contribute. The composition of cavernicole communities is not constant throughout the region and varies due to environmental and geographic factors. A major expansion of the limestone extraction industry is underway in the Jaintia Hills and elsewhere in Meghalaya. This will inevitably cause significant destruction and perturbation of cavernicole habitat. It would be prudent to implement formal studies to document the biospeleology of the region before significant loss or damage occurs.


Identifying the link between lineament and cave passage trends to comprehend fractures continuity and influence on the Kinta Valley karst system, 2012, Kassa Solomon, Pierson Bernard, Chow Weng S. , Talib Jasmi B. Ab. .

The Kinta Valley karst landscape is characterised by residual limestone hills scattered all over the valley. The aim of this study is to ascertain the link between lineament and cave passage orientations, and to identify the main fracture controlling the karst features. To achieve that, standard cave surveying and direct lineament extraction techniques, from a 2.5m resolution spot image, were employed. Six trends of lineaments were obtained from the remnant limestone hills, and their main orientation appears to be in the NNW-SSE. Similarly, various caves were surveyed and mapped; their passage orientation analyses reveal that NNW-SSE is the prominent direction. The similarity of the lineaments orientation and caves passage trend attests that the karst formation is controlled by the geological structures. Such a similar trend observed in all hills enabled to infer the orientation of the primary structure responsible for the formation of the extant karst features. The multi-fracturing episodes rendered the Kinta Valley to be structurally complex and the karst features unravelled this effect, as evidenced by features such as circular and sinuous cave passage morphology, which developed ensuing fractures oriented in different directions.


The Prehistoric Cave Art and Archaeology of Dunbar Cave, Montgomery County, Tennessee, 2012, Simek J. F. , Blankenship S. A. , Cressler A. , Douglas J. C. , Wallace A. , Weinand D. , Welborn H.

 

Dunbar Cave in Montgomery County, Tennessee has been used by people in a great variety of ways. This paper reports on prehistoric uses of the cave, which were quite varied. The vestibule of the cave, which is today protected by a concrete slab installed during the cave’s days as an historic tourist showplace, saw extensive and very long term occupation. Diagnostic artifacts span the period from Late Paleo-Indian (ca.10,000-years ago) to the Mississippian, and include Archaic (10,000 to 3,000-years ago) and Woodland (3,000–1,000-years ago) cultural materials. These include a paleoindian Beaver Lake Point, Kirk cluster points, Little River types, Ledbetter types, numerous straight-stemmed point types, Hamilton and Madison projectile points. Woodland period ceramics comprise various limestone tempered forms, all in low quantities, and cord-marked limestone tempered wares in the uppermost Woodland layers. Shell-tempered ceramics bear witness to a rich Mississippian presence at the top of the deposit. Given this chronological span, the Dunbar Cave sequence is as complete as any in eastern North America. However, problems with previous excavation strategies make much of the existing archaeological record difficult to interpret. We present a new series of radiocarbon age determinations that show both the great time depth of the vestibule deposits and the problems with their integrity. There was also extensive prehistoric use of Dunbar Cave’s dark zone, including mineral extraction, and ritual interment of the dead. Most importantly, thirty-five petroglyphs and pictographs were made on the cave walls, most probably during the Mississippian period. These include geometric shapes, abstract compositions, and human figures including a mythological hero warrior known from other examples of Mississippian iconography. Dunbar may also have seen ritual visitation very early, i.e., during the Archaic period (ca. 5,000-years ago), entailing the placement of offerings in the cave’s interior waters.


Geoelectrical Characterization of Sulphate Rocks, 2012, Guinea Maysounave, Ander

Gypsum rocks are widely exploited in the world as industrial minerals. The purity of the gypsum rocks (percentage in gypsum mineral –CaSO4•2H2O- in the whole rock) is a critical factor to evaluate the potential exploitability of a gypsum deposit. It is considered than purities higher than 80% in gypsum are required to be economically profitable. Gypsum deposits have been studied with geoelectrical methods; a direct relationship between the electrical resistivity values of the gypsum rocks and its lithological composition has been established, with the presence of lutites being the main controlling factor in the geoelectrical response of the deposit. This phenomenon has been quantified by means of a combination of theoretical calculations, laboratory measurements and field data acquisition. A geoelectrical classification of gypsum rocks defining three types of gypsum rocks has been elaborated. Anhydrite (CaSO4) is frequently found in gypsum quarries and in no-outcropping sulphates. Because of its highest hardness than gypsum it supposes a problem for the extraction of gypsum; the fronts of the quarries in which anhydrite is found are stopped at the moment when it appears. The electrical properties of calcium sulphates have been studied by means of geoelectrical methods. The conductivity of crystals has been tested in laboratory. A direct relationship between the electrical conductivity values of the calcium sulphate rocks and its lithological composition has been established being the lutitic matrix the main controlling factor when it is percolant (connected at long range). When the rock is matrix dominant, the electrical resistivity trend is bond to the Hashin-Shtrikman lower bound for multiphase systems. On the other hand, when the rock is calcium sulphate dominant the trend shows the one of the Hashin-Shtrikman upper bound. A geoelectrical classification for calcium sulphate rocks has been elaborated. With this classification it is possible to differentiate between calcium sulphate rocks with different composition according to their electrical resistivity value. Glauberite (Na2Ca(SO4)2) is nowadays exploited as industrial mineral. Glauberite rocks usually have high lutite content in their composition, together with other evaporictic minerals as gypsum, anhydrite or halite among others. There is no reference to the conductivity of glauberite rocks in the bibliography, but due to their impurity it is expected to observe values as the observed for other sulphates in the matrix domain (less than 55% in purity). Two areas of the Ebro river basin (the Zaragoza and La Rioja sectors) have been studied by means of electrical resistivity tomography profiles, in which glauberite has been found in boreholes. As example of application for the study of sulphate deposits, an electrical resistivity tomography survey has been carried out in the Pira Gypsum member (SE of Catalan margin of the Tertiary Ebro Basin, Spain). Additionally, a continuous coring drill was performed in order to support the study. Electrical imaging has been successfully applied to identify the gypsum deposits interlayered in lutite units. Another resistivity survey has been carried out in an active gypsum quarry in the Gelsa Gypsum unit (Zaragoza, N Spain). During the extraction of the rock, the most important parameters to know are the purity changes in the deposit. Sudden changes in the purity make the processing of the raw material less profitable. The performed profiles have shown different gypsum layers from which the purest layers have been identified. Electrical resistivity tomography lines are useful in prospection of gypsum deposits. However, electrical imaging prospection should be supported by an accurate petrological study of the deposits, in order to properly interpret the resistivity profiles.


THE CAVES IN THE UNDERGROUND QUARRIES OF MON CALVO DASTI PIEDMONT (ITALY), 2013, Vigna Bartolomeo, De Waele Jo, Banzato Cinzia

Many quarries for the extraction of gypsum are located in the hills of the Monferrato area (central eastern Piedmont). Close to the village of Moncalvo, Asti Province, a subterranean quarry of more than 20 km long is present. During the excavations a fracture from which water gushed at a pressure of 3 atm has been intercepted in 2005. The underground works have been suspended immediately and, after only a few hours a water flow comprised between 3000 and 4000 Ls-1 has flooded the quarry tunnels filling a volume of over 60,000 m3. After more than one month of pumping the flooded areas have been made accessible again, revealing a thin rock diaphragm that separated the quarry tunnel from a natural cave, which failed under the high hydraulic pressure. Through this small gap it has been possible to access an extensive karst network that previously was completely submerged. During the following quarry operations a second natural cave has been encountered, belonging to the same system but physically divided from the first cave by some metres of sediments. The total development of this cave system is around 1 km. The exploration of these caves has allowed to gather an interesting set of observations that have contributed to elaborating a speleogenetic model. The first information regards the impressive

amount of snottites present along the walls of the caves, and the overall thickness of gypsum rock subdued to weathering, reaching up to 30 cm. There are many morphologies that clearly demonstrate the caves being formed in phreatic conditions, such as pendants and corrosion cupola, but also flat corrosion bevels and V-shaped cross-sections, further evidences of formation in saturate conditions. The stratigraphic asset of the area surely has played a fundamental role in the formation of these karst systems. From bottom to top there is a thick shale sequence, and a thin discontinuous and extremely well karstified marly limestone bed that seemed to have enhanced the hydrological flow in the above lying gypsum beds. The principal cave systems are formed in between the first and second bed of gypsum, along a shaly finely stratified interbed rich in organic material. On the floor of the main passage there are many rather small subvertical conduits that develop up to the underlying limestone bed thus favoring the upward movement of water and the dissolution of the gypsum rocks. The subterranean excavations also have intercepted other caves, most of them of much smaller size, often reaching some cubic metres in size and partially filled with large gypsum crystals, grown by the continuous but slow feeding of slightly supersaturated waters.


The mineral springs of the Scrajo spa (Sorrento peninsula, Italy): a case of natural seawater intrusion, 2013, Corniello A. , Trifuoggi M. , Ruggieri G.

This paper deals with the mineral springs feeding the Scrajo spa in the Sorrento peninsula southeast of Naples, approximately 6 km from Castellammare di Stabia, another spa location. The Scrajo mineral water is sulphureous, salt-bromine-iodic and CO2-rich. The two hydromineral areas fall within the groundwater basin of Mt. Faito formed chiefly by limestones. Due to the high permeability of the limestones, there is considerable rainwater infiltration which recharges a basal fresh groundwater resting on denser seawater. This groundwater body feeds the mineral springs of the Scrajo spa, the springs of Castellammare di Stabia and some submarine springs. All the data gathered for the Scrajo springs led to propose the following mineralisation scheme: (1) The basal fresh groundwater of Mt. Faito (on underlying seawater) receives endogenous contributions of CO2 and H2S which cause a ‘‘natural’’ seawater intrusion within the fresh groundwater; (2) The upwelling of gases would appear to occur via the major faults which bound Sorrento peninsula to the NW; (3) During the year, the chemistry of the springs changes according to different degrees of seawater intrusion: the minimum occurs in June and the maximum in November. The close interaction between the sea and the Scrajo’s mineral waters (but also those of Castellammare di Stabia) highlights their particular vulnerability not only to overextraction of groundwater but also to climate change. Finally, a hypothesis is presented to explain the connection between the mineral waters rich in CO2 and H2S and the concentration of karst phenomena observed in the Scrajo area.


Characteristics of gas disaster in the Huaibei coalfield and its control and development technologies, 2014, Wang L. , Cheng Y. , An F, Zhou H. , Kong S. , Wang W.

The Huaibei coalfield is in the East China Economic Area, which is rich in coal and gas resources. However, hundreds of coal and gas outburst accidents have occurred because of the complex geological structures of the coalfield. Based on theoretical analysis and field statistics, the characteristics of regional geological structures and the coal measure strata evolution in the Huaibei coalfield were researched, and gas resource distribution and gas parameters were statistically analyzed to determine the dominant controlling factors of gas occurrence and gas dynamic disaster. The results indicated that the Huaibei coalfield has undergone complex tectonic evolution, causing obvious differences in gas storage in different blocks of different mining areas, which exhibits a pattern of high amounts of gas in the south and east, and low amounts of gas in the north and west. The coal seam and gas occurrence have a bipolar distribution in the coalfield caused by multiple tectonic movements, and they are deeply buried. Horizontal tectonic stress plays a dominant role in gas outburst, and the thermal evolution and trap effects of magma intrusion increase the possibility and extent of gas outburst. Considering coal seam and gas occurrence characteristics in the coalfield, we propose a new technology for deep coal reservoir reconstruction which combined present underground regional gas control methods and surface well extraction methods. The technology has three effects: developing gas resources, improving coal mining safety level and reducing greenhouse gas emissions, which has been practiced to be effective in coal mines in the Huaibei coalfield.


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