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Community news

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 underfit stream is a small stream that flows along a cave passage that was enlarged to its current size by an earlier, larger stream. commonly underfit streams are found flowing under vadose conditions along the floors of drained phreatic tubes, long abandoned by the phreatic flow that enlarged them. underfit streams may also occur if the major flow in a vadose streamway is captured to lower levels by the opening of a new shaft. the main flow no longer uses the downstream passages, leaving any tributaries to amalgamate as an underfit stream [9].?

Checkout all 2699 terms in the KarstBase Glossary of Karst and Cave Terms


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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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 mud (Keyword) returned 96 results for the whole karstbase:
Showing 76 to 90 of 96
Influence of depositional setting and sedimentary fabric on mechanical layer evolution in carbonate aquifers, 2006,
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Graham Wall Brita R. ,
Carbonate aquifers in fold-thrust belt settings often have low-matrix porosity and permeability, and thus groundwater flow pathways depend on high porosity and permeability fracture and fault zones. Methods from sedimentology and structural geology are combined to understand the evolution of fracture controlled flow pathways and determine their spatial distribution. Through this process bed-parallel pressure-solution surfaces (PS1) are identified as a fracture type which influences fragmentation in peritidal and basinal carbonate, and upon shearing provides a major flow pathway in fold-thrust belt carbonate aquifers. Through stratigraphic analysis and fracture mapping, depositional setting is determined to play a critical role in PS1 localization and spacing where peritidal strata have closer spaced and less laterally continuous PS1 than basinal strata. In the peritidal platform facies, units with planar lamination have bed-parallel pressure-solution seams along mudstone laminae. In contrast, burrowed units of peritidal strata have solution seams with irregular and anastamosing geometries. Laminated units with closely spaced bed-parallel solution seams are more fragmented than bioturbated units with anastamosing solution seams. In the deeper-water depositional environment, pelagic settling and turbidity currents are the dominant sedimentation processes, resulting in laterally continuous deposits relative to the peritidal platform environment. To quantify the fracture patterns in the basinal environment, mechanical layer thickness values were measured from regions of low to high bed dip. The results define a trend in which mechanical layer thickness decreases as layer dip increases. A conceptual model is presented that emphasizes the link between sedimentary and structural fabric for the peritidal and basinal environments, where solution seams localize in mud-rich intervals, and the resulting pressure-solution surface geometry is influenced by sedimentary geometry (i.e., stacked fining upward cycles, burrows, planar laminations). In both facies types, laterally continuous PS1 can behave as mechanical layer boundaries. As layer-parallel slip increases to accommodate shear strain in the fold-thrust belt, more PS1 behave as mechanical layer boundaries

Etude de la karstification partir des donnes de forages : le cas des Monts de Tlemcen (Algrie), 2007,
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Bensaoula Fouzia
STUDY OF KARSTIFICATION FROM BOREHOLE DATA. THE CASE OF THE TLEMCEN MOUNTAINS. The Tlemcen mountains are the second largest carbonate massif in the north-west of Algeria, after the one of the Saida mountains. It is a large horst structure trending NE-SW, composed mainly of Upper Jurassic and Lower Cretaceous formations. The aquifers within it constitute the main water resource of the area. They are tapped by more than 160 boreholes, which constitute a great tool for studying the karst, especially its phreatic part. In the holes made by conventional drills, the total loss of drilling mud indicate karstification. The registration of the altitude of those losses permit to recognize the fissured and karstified levels. Three different aspects of karstifications were observed: an important fracturation, seen by complete loss of drilling mud during the drilling, important caves, observed by the free fall of drilling tools, and caves filled by karstic sediments, found thanks to diagraphies and the study of material brought up by the drilling. A statistical analysis of these data permitted to evidence the following elements: The dolomitic facies is much more dominant than the limestone facies; The frequency of incidences slowly decreases with depth; The fracturation is most important in the first 120 to 130 m below the top of the karstified formations, although it does not disappear at depth. In the breakdown zone of Tlemcen, situated in the northern piedmont part of the Tlemcen mountain, 26 boreholes permitted to draw an isopach map of the thickness of the karstic cover as well as the top of the karstified formation. This one shows two hollow zones below 100 m depth in the SW and NE parts. The top of the jurassic carbonates shows a very irregular surface which might correspond to a karstic paleorelief that was drowned by the Miocene transgression. Finally, the last map shows a karstified surface that can possibly be connected to a pseudo-paleo-piezometric surface.

Petrographic and geochemical study on cave pearls from Kanaan Cave (Lebanon), 2007,
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Nader Fadi. H.
The Kanaan cave is situated at the coastal zone, north of Beirut City (capital of Lebanon). The cave is located within the upper part of the Jurassic Kesrouane Formation (Liassic to Oxfordian) which consists mainly of micritic limestone. Twenty seven cave pearls were subjected to petrographic (conventional and scanning electron microscopy) and geochemical analyses (major/trace elements and stable isotopes). The cave pearls were found in an agitated splash-pool with low mud content. They are believed to have formed through chemical precipitation of calcite in water over-saturated with calcium. The nucleus and micritic laminae show ? 18OV-PDB values of about -5.0 and ? 13C V-PDB values of -11.8, while the surrounding calcite spar laminae resulted in ?18OV-PDB ranging between -5.3 and -5.2, and ? 13C V-PDB between -12.3 and -12.1. A genesis/diagenesis model for these speleothems is proposed involving recrystallization which has selectively affected the inner layers of the cave pearls. This is chiefly invoked by sparry calcite crystals invading the inner micrite cortical laminae and the nuclei (cross-cutting the pre-existing mud-envelopes), and the slight depletion in ? 18O values from inner to outer cortical layers. The calculated ? 18OV-SMOW of the water (-4.2) matches with data on meteoric water signature for the central eastern Mediterranean region.

Pleistocene depositional history in a periglacial terrane: A 500ka record from Kents Cavern, Devon, United Kingdom., 2007,
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Lundberg, J. And Mcfarlane, D. A.
The signifi cance of the stratigraphic record in Kents Cavern, Devon, United Kingdom, to the interpretation of the British Quaternary is confi rmed on the basis of a thorough reexamination of the deposits in concert with 2 new Al-Be cosmogenic and 34 new thermal ionization mass spectrometry U-Th dates. The deposits show evidence of complex reworking in response to periglaciation, and the main fl owstone deposit is a multilayered complex spanning marine isotope stage (MIS) 11?3. The lowermost unit of fl uvial sands is Cromerian or older. The second deposit, a muddy breccia of surfi cial periglacial solifl uction material containing Acheulian artifacts, entered the cave during MIS 12 from highlevel openings to the west. Cave bears denned in the cave during MIS 11, the Hoxnian interglacial; their bones are capped by an MIS 11 calcite fl owstone layer. From MIS 11 onward, each interglacial period and the warmer interstadial periods (MIS 11, 10b, 9, 7, 6b, 5, and 3) produced calcite fl owstone deposition in the cave; MIS 9 was particularly active. Each glacial or stadial period (MIS 10c, 10a, 8, 6c, 6a, 4, and 2) caused periglacial activity in the cave, during which the thinner layers of calcite were fractured by frost heave and redistributed by solifl uction. This sequence was interrupted during MIS 3?2 with the introduction of sandy and stony clastic sediments from entrances to the east, and fi nally cemented by the uppermost layer of MIS 1 fl owstone. This is the fi rst publication of welldated and clearly documented evidence of frost heaving in interior cave passages. The Kents Cavern record of continuous, repeated sedimentation events followed by frost shattering and remobilization events over the past 500 k.y. is probably unique in the karst literature and establishes Kents Cavern as a site of international scientifi c interest.

Petrographic and geochemical study on cave pearls from Kanaan Cave (Lebanon), 2007,
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Nader Fadi H.
The Kanaan cave is situated at the coastal zone, north of Beirut City (capital of Lebanon). The cave is located within the upper part of the Jurassic Kesrouane Formation (Liassic to Oxfordian) which consists mainly of micritic limestone. Twenty seven cave pearls were subjected to petrographic (conventional and scanning electron microscopy) and geochemical analyses (major/trace elements and stable isotopes). The cave pearls were found in an agitated splash-pool with low mud content. They are believed to have formed through chemical precipitation of calcite in water over-saturated with calcium. The nucleus and micritic laminae show ? 18OV-PDB values of about -5.0 and ? 13C V-PDB values of -11.8, while the surrounding calcite spar laminae resulted in ?18OV-PDB ranging between -5.3 and -5.2, and ? 13C V-PDB between -12.3 and -12.1. A genesis/diagenesis model for these speleothems is proposed involving recrystallization which has selectively affected the inner layers of the cave pearls. This is chiefly invoked by sparry calcite crystals invading the inner micrite cortical laminae and the nuclei (cross-cutting the pre-existing mud-envelopes), and the slight depletion in ? 18O values from inner to outer cortical layers. The calculated ? 18OV-SMOW of the water (-4.2) matches with data on meteoric water signature for the central eastern Mediterranean region.

Evidence for habitual use of fire at the end of the Lower Paleolithic: Site formation processes at Qesem Cave, Israel, 2007,
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Karkanas, P. , Shahackgross, R. , Ayalon, A. , Barmatthews, M. , Barkai, R. , Frumkin, A. , Gopher, A. , And Stiner, M. C.
The Amudian (late Lower Paleolithic) site of Qesem Cave in Israel represents one of the earliest examples of habitual use of fire by middle Pleistocene hominids. The Paleolithic layers in this cave were studied using a suite of mineralogical and chemical techniques and a contextual sedimentological analysis (i.e., micromorphology). We show that the lower ca. 3 m of the stratigraphic sequence are dominated by clastic sediments deposited within a closed karstic environment. The deposits were formed by small scale, concentrated mud slurries (infiltrated terra rosa soil) and debris flows. A few intervening lenses of mostly in situ burnt remains were also identified. The main part of the upper ca. 4.5 m consists of anthropogenic sediment with only moderate amounts of clastic geogenic inputs. The deposits are strongly cemented with calcite that precipitated from dripping water. The anthropogenic component is characterized by completely combusted, mostly reworked wood ash with only rare remnants of charred material. Micromorphological and isotopic evidence indicates recrystallization of the wood ash. Large quantities of burnt bone, defined by a combination of microscopic and macroscopic criteria, and moderately heated soil lumps are closely associated with the woodash remains. The frequent presence of microscopic calcified rootlets indicates that the upper sequence formed in the vicinity of the former cave entrance. Burnt remains in the sediments are associated with systematic blade production and faunas that are dominated by the remains of fallow deer. Use-wear damage on blades and blade tools in conjunction with numerous cut marks on bones indicate an emphasis on butchering and prey-defleshing activities in the vicinity of fireplaces.

Interaction between a dam site and karst springs: The case of Supramonte (Central-East Sardinia, Italy), 2008,
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De Waele Jo, Forti Paolo

Sardinia is one of the Italian regions with the greatest number of dams per inhabitants, almost 60 for a population of only 1.5 million people. Many of these dam sites are located on non-carbonate rocks along the main rivers of the Island and their waters are used for irrigation, industrial, energy supply, drinking and flood regulation purposes.  The Pedra 'e Othoni dam on the Cedrino river (Dorgali, Central-East Sardinia) is located along the threshold of the Palaeozoic basement on the Northern border of the Supramonte karst area, where water is forced to flow out of the system through several resurgences, the most famous of which is the Su Gologone vauclusian spring, used for drinking water supply. The other main outflows of the system, Su Tippari and San Pantaleo springs, are at present almost permanently submerged by the high water level of the Pedra 'e Othoni dam. In the near future water will be supplied also to other communities with a possible increase of water taken from the spring.

The dam, originally meant to regulate the flooding of Cedrino river but actually used for all sorts of purposes (electricity supply, drinking water, irrigation of farmlands, industrial uses), has a maximum regulation altitude of 103 m a.s.l., only slightly less than a meter below the Su Gologone spring level (103.7 m), and 4 and 9 m respectively above the submerged Su Tippari and San Pantaleo springs.

During floods of the Cedrino river, occurring on average twice a year, also the Su Gologone spring becomes submerged by the muddy waters of the lake for a time ranging between a couple of hours up to several days, making water supply impossible. 

The analysis of the available meteorological and hydrogeological data relative to the December 2004 flood, one of the severest of the past 100 years, suggests that the reservoir is filled in a few days time. Several flooding scenarios have been reconstructed using digital terrain models, showing that backflooding submerges most of the discharge area of the aquifer, having important repercussions also on the inland underground drainage system. The upstream flood prone areas prevalently comprise agricultural lands with some sparse houses, but also highly frequented tourist facilities. Fortunately flooding occurs outside the tourist season, thus limiting risk to a limited number of local inhabitants. Massive discharge at the dam site, instead, determines a more hazardous situation in the Cedrino coastal plain, where population density in low lying areas is much higher. To avoid flooding hazard upstream the water level in the lake should be regulated, keeping it low in the flood prone seasons, and having it filled from the end of the winter in order to have enough water stocked before the beginning of the summer. Discharge at the dam site, instead, should be done cautiously, preventing severe flooding of the coastal Cedrino plain.


Die Erforschung des Unterfelds in der Hirlatzhhle, 2008,
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Meyer U. , Buchegger G.
The results from six years of exploration in the eastern part of Hirlatz Cave in the Dachstein Mountains are presented. Boltclimbing led to the discovery of a huge tunnel 60 m above the canyon at the former end of the cave. The tunnel opened out into a big dome called Kolosseum and continued through more canyons to a 80 m climb. Above the climb, the passage sinks into the waters of a lake at the contact zone of limestone and dolomite. Two sumps were dived, then a dry shortcut could be found that enabled further exploration. More spectacular discoveries followed, but finally the main tunnel forked and all passages submerged into a muddy sump area. All in all more than 6 km of new galleries could be surveyed in this area of the cave, called Unterfeld. The total length of the cave reached 96.2 km in February 2008. This article gives a short outline of the history of explorations, a more detailed description of the new passages and some observations of geological and hydrological relevance.

Present-day sedimentary facies in the coastal karst caves of Mallorca island (western Mediterranean), 2009,
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Forns J. J. , Gins J. , And Grcia F.
In spite of the increasing number of papers on cave sediments published during the last few decades, no one has focused from a sedimentological point of view on the processes that take place specifically within the coastal karst areas of carbonate islands. The objective of the present investigations is to deal with the sedimentary processes that take place inside two littoral caves of Mallorca (western Mediterranean), characterizing the different facies existing in the particular geological, geochemical, and hydrological setting that represents this very specific cave sedimentary environment. The recent exploration of extensive underwater galleries and chambers into some outstanding coastal caves of the island, has permitted the recognition of important accumulations of present-day sedimentary infillings in their drowned passages. Both the Pirata-Pont- Piqueta cave system and the Cova de sa Gleda have floors covered by muddy and/or sandy sediments which, in a wide sense, fit into two well-differentiated categories. On one hand we have allochthonous reddish mud sediments (mainly siliciclastic) and on the other hand autochthonous yellowish carbonate mud or sands. The mixing of both materials is also frequent as well as the accumulation of large blocks and debris due to the breakdown of roof and cave walls. A series of 21 manual cores was obtainedby scuba-divers in both caves, in order to collect the full thickness of sedimentary fill. Soil samples at the entrance of the two caves, as well as rock samples of the walls of both sites, were also obtained for a later comparison. Several sedimentary facies can be distinguished, which include coarse-grained deposits (entrance facies and breakdown blocks), fine-grained siliceous sediments (silts and muddy deposits with very variable organic matter content), carbonate deposits composed of calcite raft accumulations and/ or weathering-released limestone grains, and mixed facies including diverse proportions of the other sediment types. There are also some relict deposits composed of siliceous red silts, which are affected by polygonal desiccation cracks. In all the cases, the siliciclastic elements (quartz and feldspars, mainly) are related to rain events supplying dust of Saharan origin. The deposits and facies described herein correspond to different sedimentary environments that can be individualized inside the caves (collapse entrances, breakdown chambers, fully drowned passages and chambers, pools with free water surface), and reflect very specific hydrological, geochemical, and mechanical processes related to the coastal nature of the studied karst caves.

Hypogene gypsum karst and sinkhole formation at Moncalvo (Asti, Italy), 2010,
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Vigna B. , Fiorucci A. , Banzato C. , Forti P. , De Waele J.

In the morning of February 15th 2005, during excavation works in an underground gypsum quarry at Moncalvo (Monferrato area, Asti, Northern Italy), a water-bearing fracture was intercepted at level 134 m a.s.l. During the night a large amount of water (approximately 60,000 m3) and mud invaded the quarry tunnels reaching a height of 139 m a.s.l. the morning of the day after. Meanwhile a large sinkhole (20 m wide and 10 m deep) formed on the surface. Hydrogeological surveys were immediately carried out to follow the quickly evolving situation, while speleological and geomorphological fieldwork was made possible only seven months later. Two important caves were discovered both showing clear evidence of a hypogenic origin with sculpted morphologies due to slowly flowing water under pressure. The sinkhole formed by the collapse of one of the main chambers of the biggest of these caves, when buoyant support provided by the water started to decrease due to lowering of the virtual water table. The recharge of this karst system is from below and only very minor quantities of infiltration water come from the above lying surface, as has also been confirmed by hydrochemical analysis. This hypogene karst is completely invisible at the surface and develops entirely underground showing no relation whatsoever with the surface. Its presence is therefore extremely difficult to reveal and such types of karst can thus make up extremely dangerous situations. This is the first example of hypogene gypsum cave related to ascending waters in Italy.


Landscape evolution in southeast Wales: evidence from aquifer geometry and surface topography associated with the Ogof Draenen cave system, 2011,
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Simms Michael J, Farrant Andrew R

The evolution of the Ogof Draenen cave system, in south-east Wales, has been profoundly influenced by the geometry of the karst aquifer and its relationship with changes in the surface topography. Using data from within the cave combined with a model of the aquifer geometry based on outcrop data, we have estimated the location and elevation of putative sinks and risings for the system by extrapolating from surveyed conduits in the cave. These data have enabled us to assess the scale and pattern of scarp retreat and valley incision in the valleys of the Usk, Clydach and Lwyd, that together have influenced the development of the cave. From this we can construct a relative chronology for cave development and landscape evolution in the region. Our data show that scarp retreat rates along the west flank of the Usk valley have varied by more than an order of magnitude, which we interpret as the result of locally enhanced erosion in glacial cirques repeatedly occupied and enlarged during successive glacial cycles. This process would have played a key role in breaching the aquiclude, created by the eastward overstep of the Marros Group clastics onto the Cwmyniscoy Mudstone, and thereby allowed the development of major conduits draining further south. In the tributary valleys incision rates were substantially greater in the Clydach valley than in the Lwyd valley, which we attribute to glacial erosion predominating in the north-east-facing Clydach valley and fluvial erosion being dominant in the south-facing Lwyd valley. There is evidence from within Ogof Draenen for a series of southward-draining conduits graded to a succession of palaeoresurgences, each with a vertical separation of 4-5 m, in the upper reaches of the Lwyd valley. We interpret these conduits as an underground proxy for a fluvial terrace staircase and suggest a direct link with glacial-interglacial cycles of surface aggradation and incision in the Lwyd valley. Fluvial incision rates for broadly analogous.


Formation and accumulation of oil and gas in marine carbonate sequences in Chinese sedimentary basins, 2011,
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Jin, Z.

Advances in studies of formation and accumulation mechanisms of oil and gas in marine carbonate sequences have led to continuing breakthroughs of petroleum exploration in marine carbonate sequences in Chinese sedimentary basins in recent years. The recently discovered giant Tahe Oil Field and Puguang Gas Field have provided geological entities for further studies of the formation and accumulation of oil and gas in marine carbonate sequences. Marine carbonate sequences in China are characterized by old age, multiple structural deformation, differential thermal evolution of source rocks, various reservoir types (i.e. reef-bank complex and paleo-weathered crust karst reservoir), uneven development of caprocks, especially gypsum seal, and multi-episodes of hydrocarbon accumulation and readjustment. As a result, the formation of hydrocarbon accumulations in the Chinese marine carbonate sequences has the following features: (i) the high-quality marine source rocks of shale and calcareous mudstone are often associated with siliceous rocks or calcareous rocks and were deposited in slope environments. They are rich in organic matter, have a higher hydrocarbon generation potential, but experienced variable thermal evolutions in different basins or different areas of the same basin. (ii) High quality reservoirs are controlled by both primary depositional environments and later modifications including diagenetic modifications, structural deformations, and fluid effects. (iii) Development of high-quality caprocks, especially gypsum seals, is the key to the formation of large- and medium-sized oil and gas fields in marine carbonate sequences. Gypsum often constitutes the caprock for most of large sized gas fields. Given that Chinese marine carbonate sequences are of old age and subject to multiple episodes of structural deformation and superposition, oil and gas tend to accumulate in the slopes and structural hinge zones, since the slopes favor the development of effective assemblage of source-reservoir-caprock, high quality source rocks, good reservoirs such as reef-bank complex, and various caprocks. As the structural hinge zones lay in the focus area of petroleum migration and experienced little structural deformation, they are also favorable places for hydrocarbon accumulation and preservation.


Clastic Sediments in Caves, 2012,
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Springer, Gregory S.

This article focuses on the natures, origins, and significances of clastic sediments in caves. Clastic sediments are fragments of preexisting rocks that have been transported and redeposited. Streams transport large quantities of clastic sediments through caves, including stream gravels and mud, but clastic sediments also move as gravity flows by slumping and sliding. Sedimentology and stratigraphy offer the means to understand the origins and transport mechanisms behind individual clastic deposits. Together, the two methodologies consider layering within deposits and grain sizes, sorting, mineralogies, and sedimentary structures within individual beds. Facies are recognized where those variables include diagnostic properties tied to particular depositional processes or driving forces. As is shown using examples, stratigraphy and facies analysis make it possible to reconstruct cave or landscape histories, including system responses to disturbances such as climate change and land use. Notably, system responses typically reflect changes in sediment supply, hydraulic gradients, or obstructions. These factors are recorded in passage morphologies, which should always be considered when studying clastic sediments in caves, and examples are cited.


Provenance and geological significance of red mud and other clastic sediments of the Mugnano cave (Montagnola Senese, Italy), 2012,
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Lacoviello Francesco, Martini Ivan

 

The Mugnano cave is characterized by a thick clastic sedimentary fill showing a great variability of sedimentary facies, ranging from clay to coarse-grained sand deposits. This paper deals with combined sedimentological and mineralogical (XRD and SEM) studies of these sediments and bedrock insoluble residues in order to understand the origin and geological significance of cave deposits, with particular attention to red mud sediments, often considered as the residue of host rock dissolution. Three different sedimentary facies were recognized: i) YS, yellow sand with occasionally shell fragments, testifying the arrival of sediments from the surrounding landscape; ii) RS, red laminated mud; iii) GS, grey and red-grey mud and sand, dolomite-rich sediments. Furthermore, the results obtained in the present study allowed the identification of two fingerprint minerals: i) quartz, present only as traces in the limestone host-rock, and ii) dolomite, certainly related to the incomplete bedrock dissolution. Results obtained by this multidisciplinary approach testify that no one of the investigated sediments is representative of a completely autochthonous sedimentation (i.e. accumulation of insoluble residue of limestone in a cave environment). In fact, all the three sedimentary facies show a bulk composition rich in quartz, a mineral indicating an external origin for these sediments. Also the grey sediments, despite of their high content of bedrock- related dolomite, are quite rich in quartz and they testify the mixing of autochthonous and allocthonous sediments. The clay fraction of cave sediments shows strong compositional similarities with bedrock insoluble residue and consequently its analysis cannot be considered as a clear proxy for distinguishing between different parent materials. Therefore, the origin of these cave deposits is dominantly related to external sediments inputs, with terra rossa surface soils as the most probable parent material for red mud sediments.


Mud stalagmite-like formations in caves of the Crimea, 2012,
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Samokhin, G. V.

The paper provides a brief review of the mud stalagmites in various regions of the World. Genetic groups of mud stalagme-like formations are characterized. Description of mud stalagmites in Crimean caves is given for the first time. Such speleothems are found in the V. Dublyansky Chamber in the Red Cave (Dolgorukovsky Massif).
 


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