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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 meltwater is water derived from the melting of snow pack or of a glacier [16].?

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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 facies analysis (Keyword) returned 7 results for the whole karstbase:
Barbuda--an emerging reef and lagoon complex on the edge of the Lesser Antilles island are, 1985, Brasier M, Donahue J,
The Pliocene to Holocene limestones of Barbuda have formed on a wide, shallow, outlying bank of the Lesser Antilles island arc, some 50 km east of the older axis of the Limestone Caribbees and 100 km east of the newer axis of the active Volcanic Caribbees. Contrasts with neighbouring islands of similar size include the lack of exposed igneous basement or mid-Tertiary sediments, the dominance of younger flat-lying carbonates, and the greater frequency of earthquake shocks. The history of emergence of the island has been studied through aerial reconnaissance, mapping, logging, hand coring, facies and microfacies analysis. These show a pattern of progressively falling high sea level stands (from more than 50 m down to the present level) on which are superimposed at least three major phases of subaerial exposure, when sea levels were close to, or below, their present level. This sequence can be summarized as follows: 1, bank edge facies (early Pliocene Highlands Formation) deposited at not more than c. 50-100 m above the present sea level; 2, emergence with moderate upwarping in the north, associated with the Bat Hole subaerial phase forming widespread karst; 3, older Pleistocene transgression with fringing reefs and protected bays formed at l0 to l5 m high sea level stands (Beazer Formation); 4, Marl Pits subaerial phase with widespread karst and soil formation; 5, late Pleistocene transgression up to m high stand with fringing and barrier reefs, protected backreefs and bays (Codrington Formation Phase I); 6, gradual regression resulting in emergence of reefs, enclosure of lagoons, and progradation of beach ridges at heights falling from c. 5 m to below present sea level (Codrington Phase II); 7, Castle Bay subaerial phase produced karst, caliche and coastal dunes that built eastwards to below present sea level; and 8, Holocene transgression producing the present mosaic, with reefs, lagoons and prograding beach ridge complexes, with the present sea level reached before c. 4085 years BP. The evidence suggests that slight uplift took place in the north of the island after early Pliocene times. Subsequent shoreline fluctuations are consistent with glacio-eustatic changes in sea level, indicating that the island has not experienced significant uplift during the Quaternary

Platform-top and ramp deposits of the Tonasa Carbonate Platform, Sulawesi, Indonesia, 1997, Wilson M. E. J. , Bosence D. W. J. ,
This study presents a detailed facies analysis of shallow-water platform and ramp deposits of an extensive Tertiary carbonate platform. Temporal and spatial variations have been used to construct a palaeogeographic reconstruction of the platform and to evaluate controls on carbonate sedimentation The late Eocene to mid-Miocene shallow-water and outer ramp/basinal deposits of the Tonasa Carbonate Platform, from the Pangkajene and Jeneponto areas of South Sulawesi respectively, formed initially as a transgressive sequence in a probable backarc setting. The platform was dominated by foraminifera and had a ramp-type southern margin. Facies belts on the platform trend east-west and their position remained remarkably stable through time indicating aggradation of the platform-top. In comparison outer ramp deposits prograded southwards at intervals into basinal marls. Tectonics, in the form of subsidence, was the dominant control on accommodation space on the Tonasa Carbonate Platform. The location of barriers' and the resultant deflection of cross-platform currents, together with the nature of carbonate producing organisms also affected sedimentation, whilst eustatic or autocyclic effects are difficult to differentiate from the affects of tectonic tilting. Moderate- to high-energy platform top or redeposited carbonate facies may form effective hydrocarbon reservoirs in otherwise tight foraminifera dominated carbonates, which occur widely in SE Asia, and have not been affected by extensive porosity occlusion

Facies differentiation and sequence stratigraphy in ancient evaporite basins - An example from the basal Zechstein (Upper Permian of Germany), 1999, Steinhoff I. , Strohmenger C. ,
Due to excellent preservation, the Werra Anhydrite (Al), the upper member of the Upper Permian Zechstein cycle I (Ist cycle, Z1), is readily studied in terms of the distribution of sulfate facies and sequence stratigraphy that can be interpreted from these facies. In this study cores taken from seven wells in the Southern Zechstein Basin were examined for their sedimentary structures and various petrographic features. Facies interpretation and depositional sequences are based on detailed examination of core material. Four main facies environments have been identified: (I) supratidal (II) intertidal (III) shallow subtidal, and (IV) deeper (hypersaline) subtidal. These are further subdivided into 10 subfacies types: (1) karst and (2) sabkha within the supratidal environment (I), (3) algal tidal-flat, (4) tidal flat and (5) beach deposit within the intertidal environment (II), (6) salina, and (7) sulfate arenites within the shallow subtidal enviromnent (III). The (8) slope subfacies type commonly associated with (9) turbidites and the (10) basin subfacies type subdivide the deeper subtidal environment (IV). Vertical stacking patterns of these facies and subfacies types reveal the sequence stratigraphic development of the sulfate cycles in response to sea-level and salinity fluctuations. The lower Werra Anhydrite (belonging to Zechstein Sequence ZS2) is characterized by a transgressive systems tract (IST) overlying the transgressive surface of Zechstein Sequence ZS2 within the Al-underlying upper Zechstein Limestone (Cal). The TST of the AT is several tens of meters thick in platform areas, where it is built up by sulfate arenites and swallow-tail anhydrite-after-gypsum, and thins out to a few meters of thickness toward the condensed basinal section, where laminites ('Linien-Anhydrit') are predominant. Most of the Al succession consists of three relatively thick parasequences belonging to the highstand systems tract (HST) that shows typical prograding sets. Enhanced platform Buildup, including sulfate arenites, salina deposits, intertidal sediments, and sabkha precipitation as well as turbidite shedding off the platforms produced marginal ''sulfate walls' up to 400 m thick as platform to slope portions of the Werra Anhydrite. Seaward, the Al thins to a few tens of meters of laminated sulfate basin muds. Increasingly pronounced Al topography during highstand narrowed the slope subfacies belt parallel to the platform margin This contrasts with the broad but considerably thinner slope deposits of transgressive times with much shallower slopes. The ensuing sea-level lowstand is reflected by a sequence boundary on top of the karstified Al-platform and a lowstand wedge (Zechstein Sequence ZS3) overlying portions of the slope and basinal subfacies of the Al highstand systems tract Beyond the lateral limits of the lowstand wedge, the sequence boundary merges with the transgressive surface of ZS3, shown by the lithologic change from the Al anhydrites to the overlying carbonates of the Stassfurt Carbonates ('Haupt Dolomit' Main Dolomite, Ca2). The Basal Anhydrite (A2), which overlies and seals the carbonate reservoir of the Ca2, can also be subdivided into systems tracts by means of facies analysis. It is, however, much less complex than the Al and is comprised almost exclusively of a transgressive systems tract of Zechstein Sequence ZS4

Unraveling the Origin of Carbonate Platform Cyclothems in the Upper Triassic Durrenstein Formation (Dolomites, Italy), 2003, Preto Nereo, Hinnov Linda A. ,
Facies analysis of the Durrenstein Formation, central-eastern Dolomites, northern Italy, indicates that this unit was deposited on a carbonate ramp, as evidenced by the lack of a shelf break, slope facies, or a reef margin, together with the occurrence of a 'molechfor' biological association. Its deposition following the accumulation of rimmed carbonate platforms during the Ladinian and Early Carnian marks a major shift in growth mode of the Triassic shallow marine carbonates in the Dolomites. The Durrenstein Formation is characterized by a hierarchical cyclicity, with elements strongly suggestive of an allocyclic origin, including (a) subaerial exposure features directly above subtidal facies within meter-scale cyclothems, (b) purely subtidal carbonate cyclothems, (c) symmetric peritidal carbonate cyclothems, and (d) continuity of cyclothems of different orders through facies boundaries. The Durrenstein cyclothems are usually defined by transgressive and regressive successions, and so most of them probably originated from sea-level oscillations. Their allocyclic origin allows their use for high-resolution correlations over distances up to 30 km. A stratigraphic section in the Tre Cime di Lavaredo area, encompassing the upper part of the Durrenstein Formation and the lower part of the overlying Raibl Formation (Upper Carnian) was studied using time-frequency analysis. A strong Milankovitch signal appeared when interference arising from a variable sedimentation rate was estimated and removed by tuning the short precession line in a spectrogram. All of the principal periodicities related to the precession index and eccentricity, calculated for 220 Ma, are present: P1 (21.9 ky); P2 (17.8 ky); E1 (400 ky), E2 (95 ky), and E3 (125 ky), along with a peak at a frequency double that of the precession, which is a predicted feature of orbitally forced insolation at the equator. Components possibly related to Earth's obliquity at ca. 35 ky and ca. 46 ky are present as well. The recovery of Milankovitch periodicities allows reconstruction of a high-resolution timescale that is in good agreement with published durations of the Carnian based on radiometric ages. The recognition of a Milankovitch signal in the Durrenstein and lower Raibl formations, as well as in other Mesozoic carbonate platforms, strongly supports a deterministic and predictable--rather than stochastic--control on the formation of carbonate platforms. Carbonate platforms might thus be used in the future for the construction of an astronomical time scale for the Mesozoic

Lower carboniferous (late Visean) platform development and cyclicity in southern Ireland: Foraminiferal biofacies and lithofacies evidence, 2003, Gallagher Sj, Somerville Id,
The stratigraphy of several well exposed late Visean carbonate successions in southern Ireland have been correlated using high resolution foraminiferal/algal biostratigraphy and detailed biofacies analysis. This study has revealed that during the lower late Visean (early Asbian) time platform mudbank and intrabank facies were deposited on a rimmed ramp that dipped southward. By upper late Visean (late Asbian to Brigantian) time, well bedded carbonates were deposited on a shallow, unrimmed platform expanse that prograded southward through a series of shallowing-upward minor cycles. Within the late Asbian successions numerous minor cycles (2-15 m thick) occur that contain distinctive lithofacies and three distinct foraminiferal biofacies. The top of these cycles can usually be identified by palaeokarst surfaces with relief of to 0.5 m associated with pedogenic features and fissures indicating initial palaeocave-forming processes. Deposits on these emergent boundary surfaces include thick palaeosols (up to I in thick) and eroded boulders of the underlying karst surfaces. The lower transgressive facies of each minor cycle often began with the deposition of shallow-water, subtidal, algal-rich limestone containing diverse foraminiferal biofacies (Biofacies type 2). New foraminiferal taxa may appear in this part of the cycle. Towards the middle part of each cycle deeper water, subtidal, foraminiferal biofacies occur, but with no significant first appearance data. The biofacies at this level in the cycle are often algal-poor limestone rich in bryozoans or crinoids (Biofacies type 1). Biostratigraphically important foraminiferal taxa often first appear or reappear in low diversity assemblages toward the top of most cycles in shallower water grainstone microfacies (Biofacies type 3) rich in dasycladacean algae

Clastic Sediments in Caves, 2012, 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.


Karstification of Dolomitic Hills at south of Coimbra (western-central Portugal) - Depositional facies and stratigraphic controls of the (palaeo)karst affecting the Coimbra Group (Lower Jurassic), 2014, Dimuccio, Luca Antonio

An evolutionary model is proposed to explain the spatio-temporal distribution of karstification affecting the Lower Jurassic shallow-marine carbonate succession (Coimbra Group) of the Lusitanian Basin, cropping out in the Coimbra-Penela region (western-central Portugal), in a specific morphostructural setting (Dolomitic Hills). Indeed, in the Coimbra Group, despite the local lateral and vertical distributions of dolomitic character and the presence of few thick sandy-argillaceous/shale and marly interbeds, some (meso)karstification was identified, including several microkarstification features. All types of karst forms are commonly filled by autochthonous and/or allochthonous post-Jurassic siliciclastics, implying a palaeokarstic nature.

The main aim of this work is to infer the interplay between depositional facies, diagenesis, syn- and postdepositional discontinuities and the spatio-temporal distribution of palaeokarst. Here, the palaeokarst concept is not limited to the definition of a landform and/or possibly to an associated deposit (both resulting from one or more processes/mechanisms), but is considered as part of the local and regional geological record.

Detailed field information from 21 stratigraphic sections (among several dozens of other observations) and from structural-geology and geomorphological surveys, was mapped and recorded on graphic logs showing the lithological succession, including sedimentological, palaeontological and structural data. Facies determination was based on field observations of textures and sedimentary structures and laboratory petrographic analysis of thin-sections. The karst and palaeokarst forms (both superficial and underground) were classified and judged on the basis of present-day geographic location, morphology, associated discontinuities, stratigraphic position and degree of burial by post-Jurassic siliciclastics that allowed to distinguish a exposed karst (denuded or completely exhumed) than a palaeokarst (covered or partially buried).

A formal lithostratigrafic framework was proposed for the local ca. 110-m-thick combined successions of Coimbra Group, ranging in age from the early Sinemurian to the early Pliensbachian and recorded in two distinct subunits: the Coimbra formation, essentially dolomitic; and the overlying S. Miguel formation, essentially dolomitic-limestone and marly-limestone.

The 15 identified facies were subsequently grouped into 4 genetically related facies associations indicative of sedimentation within supra/intertidal, shallow partially restricted subtidal-lagoonal, shoal and more open-marine (sub)environments - in the context of depositional systems of a tidal flat and a very shallow, inner part of a low-gradient, carbonate ramp. In some cases, thick bedded breccia bodies (tempestites/sismites) are associated to synsedimentary deformation structures (slumps, sliding to the W to NW), showing the important activity of N–S and NNE–SSW faults, during the Sinemurian. All these deposits are arranged into metre-scale, mostly shallowing-upward cycles, in some cases truncated by subaerial exposure events. However, no evidence of mature pedogenetic alteration, or the development of distinct soil horizons, was observed. These facts reflect very short-term subaerial exposure intervals (intermittent/ephemeral), in a semiarid palaeoclimatic setting but with an increase in the humidity conditions during the eogenetic stage of the Coimbra Group, which may have promoted the development of micropalaeokarstic dissolution (eogenetic karst).

Two types of dolomitization are recognized: one (a) syndepositional (or early diagenetic), massive-stratiform, of “penesaline type”, possibly resulting from refluxing brines (shallow-subtidal), with a primary dolomite related to the evaporation of seawater, under semiarid conditions (supra/intertidal) and the concurrent action of microbial activity; another (b) later, localized, common during diagenesis (sometimes with dedolomitization), particularly where fluids followed discontinuities such as joints, faults, bedding planes and, in some cases, pre-existing palaeokarstic features.

The very specific stratigraphic position of the (palaeo)karst features is understood as a consequence of high facies/microfacies heterogeneities and contrasts in porosity (both depositional and its early diagenetic modifications), providing efficient hydraulic circulation through the development of meso- and macropermeability contributed by syn- and postdepositional discontinuities such as bedding planes, joints and faults. These hydraulic connections significantly influenced and controlled the earliest karst-forming processes (inception), as well as the degree of subsequent karstification during the mesogenetic/telogenetic stages of the Coimbra Group. Multiple and complex karstification (polyphase and polygenic) were recognized, including 8 main phases, to local scale, integrated in 4 periods, to regional scale: Jurassic, Lower Cretaceous, pre-Pliocene and Pliocene-Quaternary. Each phase of karstification comprise a specific type of (palaeo)karst (eogenetic, subjacent, denuded, mantled-buried and exhumed).

Finally, geological, geomorphological and hydrogeological characteristics allowed to describe the local aquifer. The elaborated map of intrinsic vulnerability shows a karst/fissured and partially buried aquifer (palaeokarst) with high to very high susceptibility to the contamination.


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