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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 cavernous is adjective used to describe a rock texture in which the rock contains openings generally of a small size [20]. synonyms: (french.) caverneux; (german.) kavernos; (greek.) speleothes; (italian.) con grotte; (russian.) kavernoznij; (spanish.) cavernoso; (turkish.) kovuklu; (yugoslavian.) kavernozan. see also cavern.?

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

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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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 deep weathering (Keyword) returned 7 results for the whole karstbase:
Laterisation on limestones of the Tertiary Wankoe Formation and its relationship to the African Surface, southern Cape, South Africa, 1999, Marker M. E. , Holmes P. J. ,
The existence of erosion surfaces has long been recognised as a macroscale feature of the southern African landscape. Evidence is presented here to demonstrate that laterisation as a soil process affected the calcareous Tertiary Wankoe Formation of the southern Cape. Remnants of the Tertiary African Surface along the southern Cape Coastal Plateau are characterised by deep weathering mantles capped by duricrusts of laterite and silcrete. The limestones have been assumed to be the coastal equivalent of the inland African Surface. Through field mapping of the study locality discussed below, and through sedimentological and geochemical analysis (X-ray fluorescence spectrometry) of selected samples, it was possible to demonstrate that the laterisation process also affected these older Tertiary Limestones. However, the evidence is rarely preserved, and nowhere have complete, intact laterised profiles survived. More often, strong weathering resulted in case-hardening of the topography and the formation of dense calcrete. The implication from this coastal locality is that laterisation as a soil forming process extended from the Mid Tertiary Period until the early Pleistocene Period within this particular sub-region of southern Africa. The significance of this locality within the broader context of the African Surface remnants which occur from the Cape Peninsula in the west to the Knysna area in the east, as well as the palaeoenvironmental significance of laterisation on a substrate which is not conducive to this type of weathering, are also examined. (C) 1999 Elsevier Science B.V. All rights reserved

Basement lithology and its control on sedimentation, trap formation and hydrocarbon migration, Widuri-Intan oilfields, SE Sumatra, 1999, Tonkin P. C. , Himawan R. ,
The Widuri-lntan oilfields produce from late Oligocene sandstones of the Talang Akar Formation, which were deposited in a fluid-to-deltaic setting on the NW side of the Asri Basin, offshore SE Sumatra. The Asri Basin is of rift origin and formed during the early Oligocene, with its axis oriented in a NE-SW direction. Approximately 310 million brls of oil have been produced from the fields within the 12-by-12 mile (20-by-20 km) study area. The oil occurs in a series of structural and stratigraphic traps within slightly sinuous to meandering channel sandstone bodies. The reservoir sequence (sandstone interbedded with minor mudstone and coal) overlies basement rocks, which are predominantly Cretaceous in age. Forty-nine well penetrations have shown that the basement is composed of one of four lithologies: IB hornblende granodiorite; (2) metamorphic rocks, mainly mica schist; (3) plugs of metabasalt and related volcanic rocks; or (4) dolomitic limestone. A combination of drill cuttings, sidewall and conventional cores and FMS/FMI images has been used to identify and map the distribution of basement rock type. The basement was subjected to exposure and deep weathering prior to the formation of the Asri Basin, as evidenced by the zones of surface alteration encountered during drilling. The basement palaeotopography had a strong influence on the later distribution of major fluvial channels and sand pinch-outs. Several major faults appear to be controlled by basement lithology, especially at the boundaries of granodiorite and metabasalt intrusives. An important shear zone, oriented NW-SE, appears to have offset the basement between the main Widuri and Intan fields, and was subsequently the site of silicification of the mica schists in the basement. The Lidya field is situated where the reservoir pinches out onto eroded areas of basement silicification along this shear zone. Palaeocurrents in the upper 34-2 and 34-1 channel sandstones in the Widuri field were controlled by the orientation of this basement feature . Drape and compaction ofOligocene Talang Akar Formation sediments over eroded volcanic plugs have defined or enhanced a number of structural/stratigraphic plays, including the Widuri and Chesy fields. From seismic and well evidence, the reservoir sequence at the Indri field is underlain by dolomitic limestone and exhibits a series of unusual karst-related sinkhole and collapse structures. These are circular to slightly elliptical in shape, and extend from basement level to over 900 ft vertically into the overlying Talang Akar Formation

The Padaeng Supergene Nonsulfide Zinc Deposit, Mae Sod, Thailand, 2003, Reynolds Neal A. , Chisnall Tony W. , Kaewsang Kriangsak, Keesaneyabutr Chanan, Taksavasu Taksorn,
The Padaeng deposit near Mae Sod in western Thailand was the first supergene nonsulfide zinc deposit in the world to be developed as a large modern mining operation. The mine and associated zinc smelter, operated by Padaeng Industry Public Company Ltd. since 1984, went into production with reserves of 4.59 Mt at a grade of 28.9 percent zinc with a 10 percent zinc cutoff. Current resources are 5.14 Mt at a grade of 12.0 percent zinc with a 3 percent zinc cutoff. The Padaeng deposit is hosted by a mixed carbonate-clastic sequence of Middle Jurassic age. The deposit occurs in the hanging wall of the Padaeng fault, a major northwest-trending structure that was active through Cretaceous and Tertiary tectonism and uplift. Nonsulfide zinc ore comprises dominant hemimorphite with minor smithsonite and hydrozincite. Strata-bound ore zones occur within a northwest-dipping, deeply weathered, dolomitic sandstone; steeply dipping and irregular karstic zones in underlying massive, silty dolomite are controlled by north-trending fracture zones. Sulfide zinc-lead mineralization of Mississippi Valley type occured extensively in the vicinity of the Padaeng mine, most notably the small resources at Pha De and Hua Lon. Mineral deposits are typically sphalerite rich with minor galena and pyrite, forming small-scale open-space fillings, veins, and replacements within hydrothermal dolomite. Mineralization is dominantly strata bound within a horizon of intense hydrothermal dolomitization that forms the stratigraphic hanging wall to the nonsulfide ore zones at Padaeng. The only significant sulfide at the Padaeng mine is within this unit. Only trace sulfide occurs peripheral to, or down dip of, strata-bound or steeply dipping, nonsulfide orebodies. Sulfide mineralization is believed to have accompanied Cretaceous uplift and deformation, related to the onset of oblique subduction beneath the western margin of the Shan-Thai terrane. The nonsulfide deposit is believed to have formed when a substantial body of sulfide ore was uplifted on the margin of the Mae Sod Tertiary intermontane basin, commencing in the middle to late Miocene. Zinc-bearing acidic supergene fluids, generated by oxidation of the precursor sulfide body, reacted with carbonate in the underlying stratigraphic section to precipitate hemimorphite and smithsonite. Fluids were channeled by permeable dolomitic sandstones and by steep fracture and fault zones. Acidic fluids promoted deep weathering and karst formation, allowing mineralization to extend down dip in sandstone units for at least 150 m and vertically for a similar distance in steep structural zones. Transport of zinc out of the precursor sulfide body was facilitated by a falling water table, owing to uplift of the Padaeng fault block and a change from wet tropical to monsoonal or semiarid climatic conditions. There is no evidence for significant in situ replacement of sulfide deposits, and the leached remnants of the precursor sulfide body have been removed by erosion. The supergene process of dissolution and reprecipitation of zinc in the host rocks increased zinc grades and separation of zinc from lead, producing an economically attractive deposit. Successful exploration for this type of deposit requires a good understanding of the controls on primary sulfide mineralization and a good knowledge of local neotectonism, uplift history, hydrogeology, climatic evolution, and weathering history

Polyphase karst system in Cretaceous chalk and calcarenite of the Belgian-Dutch border, 2007, Willems Luc, Rodet Joë, L, Fournier Matthieu, Laignel Benoî, T, Dusar Michiel, Lagrou David, Pouclet André, , Massei Nicolas, Dussartbaptista Ludivine, Compè, Re Philippe, Ek C
Along the Belgian-Dutch border, underground and surface quarries dug in Cretaceous calcarenite and chalk intersect many karst features as well as deep large nodes of weathered rock. Their observation allows the reconstruction of the genesis of an original karst system resulting from the merging of initially independent endokarsts and exokarsts. Deep weathering has developed within the Cretaceous formations, creating nodes of weathered chalk and closed cavities. These phenomena are expanded over time and can form interconnected voids. Near the surface, solution pipes are generated under the coarsest deposits of a fluvial terrace capping the Cretaceous formations. These pipes develop vertically and may be related to the progressive lowering of the water table in connection with the incision of the Meuse valley. Some of these phenomena cut up the older endokarsts and organize complex systems of out-flow within the chalk.

Monadnocks of the Mekong delta: character, caves and evolution, 2011, Kiernan, Kevin

Isolated limestone hills and towers near the Gulf of Thailand coast, and granitic monadnocks that extend further inland, protrude through alluvial silts of the Mekong River delta in Vietnam and Cambodia. The form of the granitic monadnocks is guided by bedrock geometry and some exhibit extensive boulder mantles residual from deep weathering within which large boulder cave complexes occur, together with underground stream systems that feed permanent springs. The limestone hills vary in form according to differences in structure, rock purity and hill-base topographic setting and contain vertically-developed vadose invasion caves and basal floodwater stream caves. Evolution of the present day hillbase and stream cave morphology has been influenced by changes in the base level of vadose activity that have been related to changes in relative sea level, most recently as the Mekong delta has formed during the Holocene.


The nature and origin of the ghost-rocks at Bullslaughter Bay, South Wales, 2012, Rowberry Matt D. , Battiauqueney Yvonne, Blazejowski Blazej, Walsh Peter

The ‘ghost-rocks’ of the British Isles have attracted very little research interest over the years despite being widely distributed. In South Wales, the ghost-rocks of the Pembroke Peninsula are usually associated with the mudrock formations immediately above and below the Carboniferous Limestone. This study focuses on their nature and origin through a detailed investigation of the cliff sections at Bullslaughter Bay. The investigated ghost-rocks are associated with a suite of breccias, collectively termed the Gash Breccias. These are an enigmatic suite of around twenty-five large breccia masses located exclusively in the eastern part of the peninsula. They comprise huge masses of coarse, chaotic, clast-supported, monomictic breccia and represent highly disturbed features in the otherwise unbroken sequences of Carboniferous Limestone. Their origin may be karstic, tectonic, or a combination of the two. They could, theoretically, have formed at any point between the end of the Carboniferous and the Pliocene. If their origin is karstic, it cannot yet be determined if the processes were attributable to per descensum or per ascensum groundwater systems. If tectonic, it is not known whether they formed during periods of compression or extension. From our own geological and geophysical fieldwork, we believe that the breccias originated as a result of subterranean karstic processes whilst retaining an open mind with regard to the role played by tectonics. The breccia and ghost-rocks are both displayed in fine cliff exposures around Bullslaughter Bay. These sections, although not extensive, are extremely instructive. The processes that generate ghost-rock result in isovolumetric weathering of the host rock and an associated loss of density and strength. They may or may not involve the removal of certain chemical constituents in the regolith through solution and hydrolysis followed by the formation of secondary minerals, frequently clay. In reality, the precise weathering process differs according to the type of rock. The process is controlled by the permeability of each rock type in banded rocks such as mudstones or shale with banded chert whereas it is controlled by fissures and faults in homogenous rocks. This control is clearly seen in the Carboniferous Limestone around Bullslaughter Bay, where ghost-rocks are present, more commonly in case of impure or dolomitic limestone. At present, it is not clear whether the groundwater movements were caused by hydrothermal or meteoric processes and this forms the basis of ongoing research. Finally, the study considers the relationship that exists between the ghost-rock and the Gash Breccia. We examine whether there is a logical correlation between the processes that came to generate the ghost-rock and the processes responsible for the generation of the breccia. It may then be possible to accurately state whether the ghost-rock formed before, during, or after, the breccia. The reasons that the ghost-rocks of the British Isles have attracted very little research interest may stem from the fact that they have no current commercial value, have seldom presented engineering problems, and are normally difficult to date. It is clear that numerous karst related sag-subsidences in the British Isles result from the large-scale decalcification of the Carboniferous Limestone (e.g. the Tortonian Brassington Formation of the southern Pennines). There is, however, an increasingly large body of evidence to suggest that these subsidences result from the same processes that generate ghost-rock rather than those that create endokarstic voids. The subsidences may preserve stratigraphical sequences several decametres thick and reach depths and widths of many hectometres. Unfortunately, the masses of decalcified limestone below the Tortonian sediments are of no commercial interest and have hardly ever been penetrated by boreholes. Therefore, we do not know exactly what underlies the karstic fills. The possibility that most of these structures are best explained as the result of per ascensum groundwater flow is discussed.


The weathered Carboniferous limestone at Bullslaughter Bay, South Wales: the first example of ghost-rock recorded in the British Isles, 2014, Rowberry Matt D. , Battiauqueney Yvonne, Walsh Peter, Blazejowski Blazej, Boutroumazeilles Viviane, Trentesaux Alain, Krizova Lenka, Griffiths Hywel

The Carboniferous Limestone at Bullslaughter Bay hosts some of the most notable examples of deep weathering in  the British Isles as well as two members of an enigmatic suite of breccias known as the Gash Breccias. The weathered limestone has  been investigated thoroughly in order to identify the process responsible for the weathering. In this paper it is demonstrated that the  weathering is isovolumetric but the weathering profile is not characterised by a vertical gradient and its depth suggests that meteoric  waters did not contribute significantly to the weathering process. The weathered limestone has lost significant amounts of calcium and  parts are virtually decalcified. It is seen that the dominant primary minerals of illite and quartz have been preserved while secondary  clay minerals are generally absent. The weathered limestone cannot be a saprolite sensu stricto as it has been subjected to only restricted  chemical processes. It is, therefore, interpreted as a “ghost-rock”. This type of weathering results from chemical dissolution by slow  moving waters in the saturated zone. It is suggested that the weathering may have taken place during periods of emergence in the  Carboniferous, at the same time as the cyclothem tops were exposed to subaerial modification, as evidenced by omission surfaces and  palaeokarstic solution features. This is the first time that ghost-rock weathering has been reported from the British Isles.


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