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 bedding joint is a joint in rocks that runs parallel to or on a bedding plane [16].?

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

What is Karstbase?



Browse Speleogenesis Issues:

KarstBase a bibliography database in karst and cave science.

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;
See all featured articles from other geoscience journals

Search in KarstBase

Your search for archipelago (Keyword) returned 31 results for the whole karstbase:
Showing 1 to 15 of 31
Caves as Archipelagoes, 1971, Culver, David C.

Essai sur l'analyse des cavits kars-tiques du massif de Marseilleveyre et des archipels de Riou et du Frioul (Marseille), 1983, Blanc J. J. , Monteau R.
ESSAY ON THE ANALYSIS OF THE KARSTIC CAVES OF THE MASSIF DE MARSEILLEVEYRE AND OF THE RIOU-FRIOUL ARCHIPELAGOS, MARSEILLE, FRANCE - Statistical analysis and numeric treatment about the karstic caves of the Marseilleveyre Massif and Riou-Frioul archipelagos. We deal with the relationships between the lithology of consolidated speleothems, geologic framework, jointing intensity, morphology and mechanical phenomena (decompression and neotectonic actions).

La karstification de l'le haute carbonate de Makatea (Polynsie franaise) et les cycles eustatiques et climatiques quaternaires, 1991, Dessay J. , Pouchan Y. , Girou A. , Humbert L. , Malezieux J.
THE KARST 0F MAKATEA ISLAND (FRENCH POLYNESIA) AND THE CLIMATIC AND GLACIO-EUSTATISM SETTING - Located in the Central Pacific, in the northwestern part of the Tuamotu Archipelago, Makatea island (148 15 W - 15 50 S) is an uplifted, karstic, carbonate construction of Early Miocene age, which reaches 113m in height. From 1906 to 1966, phosphate deposits were exploited on Makatea Island. These phosphate deposits (apatite) overlaid the Miocene series and filled the karstic cavities in the higher regions of the island. Several traces of ancient shorelines can be observed on Makatea: 1/ three different reef formations, which reach about +27m, +7m, +1m above the present mean sea level and respectively dated 400,000 100,000 yr BP, 140,000 30,000 yr BP, between 4,470 150 yr BP and 3,720 13O yr BP; 2/ four distinct marine notch lines on the Early Miocene cliff at about +1m, +7m, +27m and +56m (or +47m on the west coast caused by tilt) above the present mean sea level; 3/ two exposed marine platforms respectively at +29m and +7m above the present mean sea level. The ages of the former makatean shores are inferred by using: (1) the Pacific glacio-eustatic sea-level curve for the last 140,000 yr BP, (2) the Pacific oxygen isotope curve for the last 900,000 yr BP, and (3) a constant uplift rate during the Pleistocene. In this way, according to their age and elevation, the sea-level indicators at about +1m, +7m and +27m (+29m) above the present mean sea level can be respectively related to the Holocene transgression (Flandrian) dated between 6,000 and 1,500 yr BP, to the last Pleistocene interglacial period (Sangamon) dated between about 130,000 and 110,000 yr BP, and to a Middle Pleistocene interglacial period (Yarmouth) dated between about 315,000 and 485,000 yr BP. If we assume that a sea level similar to the present occurred during the Yarmouth inter-glacial period, the uplift rate is valued at 0.085 mm/yr to 0.056 mm/yr. Thus the sea-level associated with the marine notch at about +56m (+47m) may be about 650,000 yr to 1 M.y. old and can be associated with another Pleistocene interglacial period (Aftonian). Consequently, as indicated by the former shores, the sea level fluctuations can be related to the major glacio-eustatic quaternary events. This climatic and eustatic setting is used to explain the karst observed on the Makatea island. Carbonate dissolution and essentially vertical karst genesis were the result of the superposition of several cycles. Each cycle was initially composed of a solution of the carbonates during an interglacial period, followed by a drainage of the saturated solutions during the marine regression associated with the consecutive glacial period. Nevertheless, this scheme is not enough to explain the specific morphology of the makatean karstic cavities and we suggest using insular phosphatisation to explain this karst genesis. It is generally accepted that phosphate rock deposits on coral reef islands are the result of chemical reaction between seabird guano and reef limestone. Furthermore, petrographic and stable isotope studies suggest several generations of phosphorite formation and reworking episodes in the history of these deposits. The primary deposition of phosphates must have begun during a glacial period. This deposition was followed by some redistribution of phosphorites during the interglacial period and by additional precipitation of apatite from meteoric waters. This assumed process of phosphogenesis is consistent with both the field observations and the geodynamic evolution of Makatea. Thus, the particular morphology of the makatean karst can be the result of the dissolution of the carbonates caused by phosphoric acid etching. This acid is derived from the evolution of the phosphorites during the pleistocene interglacial periods.

From a geographical point of view, the atoll of Mururoa belongs to the Tuamotu archipelago. In its largest dimension Mururoa (28 x 10 km) is oriented N080-degrees-E, a direction which is different from that of the other atolls of the Tuamotu, generally oriented parallel to the Pacific plate motion, N130-degrees-E. The atoll of Mururoa is built on a submarine plateau of 130 km long and 30 km wide. The western side of this plateau is 90 km long and N080-degrees-E oriented, the eastern one 40 km long and N095-degrees-E oriented. Three deep main structures of the atoll are revealed by strong aeromagnetic anomalies elongated and oriented once more N080-degrees-E. They represent ancient riftzones, similar to the present time Hawaiian ones. The most important of them, situated at southern end of the atoll, is the prolongation of the eastern plateau. The principal petrographic facies have been defined from the numerous drill holes bored in the upper 1,100 m. From the base to the top are represented volcanic deposits, a volcano-sedimentary serie of both carbonate and volcanic origin and finally reefal carbonates (limestones and dolomites). The volcanic facies represent successively submarine, transitional and aerial volcanic activity. They are commonly affected by early stage of hydrothermalism, due to lava-sea-water chemical interaction, and are frequently supported by differentiated dykes, occasionally interrupted by reefal limestones. The main geometrical distribution of the facies through the atoll and the radiochronology lead to the following model of formation : during early stages of the atoll building two main separate edifices emerged before joining and forming a single volcano. This double structure was similar to the present time morphology of Tahiti. The volcanic activity ceased 10.6 Ma ago, an age which perfectly suits a hot spot origin, at present located to the south-east of Pitcairn island

Analyses and interpretation of an industrial multi-channel seismic grid, a 2.3 km-deep industrial well (NMA-1) and two ODP (Sites 715 and 716), have generated new insights into the evolution of the Maldives carbonate system, Equatorial Indian Ocean. The present physiography of the Maldives Archipelago, a double chain of atolls delineating an internal basin, corresponds only to the latest phase of a long and dynamic evolution, far more complex than the simple vertical build-up of reef caps on top of thermally subsiding volcanic edifices. Through the Cenozoic evolution of the Maldives carbonate system, distinct phases of vertical growth (aggradation), exposure, regional or local drowning, and recovery of the shallow banks by lateral growth (progradation) have been recognized. The volcanic basement underlying the Maldives Archipelago is interpreted to be part of a volcanic ridge generated by the northern drift of the Indian plate on top of the hotspot of the island of Reunion. The volcanic basement recovered at well NMA-1 and ODP Site 715 has been radiometrically dated as 57.2 1.8 Ma (late Paleocene) by 40Ar-39Ar. Seismic and magnetic data indicate that this volcanic basement has been affected by a series of NNE-SSW trending subvertical faults, possibly associated with an early Eocene strike-slip motion along an old transform zone. The structural topography of the volcanic basement apprears to have dictated the initial geometry of the Eocene and early Oligocene Maldives carbonate system. Biostratigraphic analyses of samples, recovered by drilling in Site 715 and exploration well NMA-1, show that the Maldives shallow carbonate system was initiated during the early Eocene on top of what were originally subaerial volcanic edifices. The Eocene shallow carbonate sequence, directly overlying the volcanic basement at NMA-1, is dolomitized and remains neritic in nature, suggesting low subsidence rates until the early Oligocene. During this first phase of the Maldives carbonate system evolution, shallow carbonate facies aggraded on top of basement highs and thick deep-water periplatform sediments were deposited in some central seaways, precursors of the current wider internal basins. In the middle Oligocene, a plate reorganization of the equatorial Indian Ocean resulted in the segmentation of the hotspot trace and the spreading of the Maldives away from the transform zone. This plate reorganization resulted in increasing subsidence rates at NMA-1, interpreted to be associated with thermal cooling of the volcanic basement underlying the Maldives carbonate system. This middle Oligocene event also coincides with a regional irregular topographic surface, considered to represent a karst surface produced by a major low-stand. Deep-water carbonate facies, as seen in cuttings from NMA-1, overlie the shallow-water facies beneath the karst surface which can, therefore, be interpreted as a drowning unconformity. In the late Oligocene, following this regional deepening event, one single central basin developed, wider than its Eocene counterparts, and the current intraplatform basin was established. Since the early to middle Miocene, the shallow carbonate facies underwent a stage of local recovery by progradation of neritic environments towards the central basin. The simultaneous onset in the early middle Miocene of the monsoonal wind regime may explain the development of bidirectional slope progradations in the Maldives. During the late Miocene and the early Pliocene, several carbonate banks were locally drowned, whereas others (i.e. Male atoll) display well-developed lateral growth through margin progradations during the same interval. Differential carbonate productivity among the atolls could explain these diverse bank responses. High-frequency glacialeustatic sea-level fluctuations in the late Pliocene and Pleistocene resulted in periodic intervals of bank exposure and flooding, and developed the present-day physiography of atolls, with numerous faros along their rims and within their lagoons

The occurrence of ozone concentrations and exposure indices related to the adverse effects of ozone upon vegetation are reported for four Finnish background stations. In Finland, ozone concentrations are often near the background tropospheric values of cn. 30 ppb. Very high concentrations are not observed. The maximum 1-h average in this data set was 79 ppb. The exposure parameter, which accumulates growing season 1-h average concentrations above a 40 ppb base-line in daylight hours, gave clearly different exposure sums for the stations. These values varied between 4000 and 8500 ppb-h in the southern archipelago, 3000-6500 ppb-h in the southern coastal region, 2000-4000 ppb-h in central parts of the country, and 400-1000 ppb-h in the northern parts of the country. The date of the start of the vegetative season is important in high northern latitudes, because the spring maximum of ozone concentrations is relatively intense compared to the summer maximum. In northern Scandinavia, ozone exposures are particularly sensitive to the date of the start of the growing season. The long daylight period in northern Scandinavia is less important in this respect, since during the growing season ozone concentrations are usually below 40 ppb during the morning and evening hours. A good correlation was found between growing season average concentrations of the sum of gaseous HNO3 and particulate NO3-, and on ozone exposure index which accumulates concentrations above a 40 ppb base-line, confirming the anthropogenic origin of the elevated ozone exposures

Genetic divergence and evolutionary times: calibrating a protein clock for South-European Stenasellus species (Crustacea, Isopoda), 1997, Argano Roberto, Sbordoni Marina Cobolli, Matthaeis Elvira De, Ketmaier Valerio
We studied genetic divergence in a group of exclusively stygobiont isopods of the family Stenasellidae. In particular, we assessed evolutionary relationships among several populations of Stenasellus racovitzai and Stenasellus virei. To place this study in a phylogenetic context. we used another species of Stenasellus, S. assorgiai, as an outgroup. S. racovitzai occurs in Corsica, Sardinia and in the fossil islands of the Tuscan Archipelago, while S. virei is a polytypic species widely distributed in the central France and Pyrenean area. This vicariant distribution is believed to be the result of the disjunction of the Sardinia-Corsica microplate from the Pyrenean region and its subsequent rotation. Since geological data provide time estimates for these events, we can use the genetic distance data to calibrate a molecular clock for this group of stygobiont isopods. The calibration of the molecular clock reveals a roughly linear relationship (r = 0.753) between the genetic distances and absolute divergence times, with a mean divergence rate (19.269 Myr/DNei,) different from those previously reported in the literature and provides an opportunity to shed some light on the evolutionary scenarios of other Stenasellus species.

Les glaciers de marbre de Patagonie, Chili : un karst subpolaire ocanique de la zone australe, 1999, Maire Richard, Ultima_esperanza_team
The karst areas of Chilean Patagonia have remained virtually unknown until now because of their remoteness and very inhospitable climate. They are mainly located in two islands, Diego de Almagro and Madre de Dios, between latitude 52 and 50 South, with a subpolar and stormy climate "tempered" by heavy oceanic precipitations (7 m/ year). In Diego de Almagro the Permian and Carboniferous limestones and dolomites have been transformed into marbles with lamprophyre dikes through contact metamorphism. Situated in the outer part of the archipelagoes, these long and narrow outcrops (0.5-2km wide) are located between volcano-sedimentary formations of Upper Paleozoic (West) and the Mesozoic Patagonian batholit (East). The corallian paleoreefs are part of an accretionary prism of the Gondwana paleo-continent. The surficial and underground karstification is one of the most spectacular ones in the world. The Karren (lapies) caused by the heavy rains can be 1-4 meter(s) wide and several hundred meters long for the solution runnels. Moreover, we can often observe solution karrens both due to rain and wind direction: flat karren (horizontal laminar flow), cascading ripples (sloping laminar flow) and profiled solution forms. The surficial solution velocity is about 3 mm/50 years (from old painting traces near the quarry of Guarello, Madre de Dios); and the lamprophyres dikes (Diego de Almagro) put in relief through corrosion indicate a 40-60 cm surficial solution since the melting of pleistocene glaciers.

Remplissages karstiques tectoniss de la rgion de Marseille, 1999, Monteau, Raymond
The paleokarst fillings in the Riou and Frioul archipelagoes, the coastal ranges of MarseiIleveyre (Calanques) Notre Dame de la Garde (the Bay of Marseille) show several examples of various tectonic mechanisms due to compressive stresses. A chronology of the various phases is described: compartment process, overlapping, tilting. These deformations and the several after-episodes observed can be dated between the Lower Eocene and the Upper Pleistocene, but it is still difficult to give a more precise date. The tertiary fillings show the action of local decompression and tilting in some cases. In the detailed study of the karstic lithified deposits two kinds of tectonised sequences are shown in connection with the local tectonics.

Volcanic gaps and subaerial records of palaeo-sea-levels on Flores Island (Azores): tectonic and morphological implications, 1999, Azevedo Jmm, Ferreira Mrp,
The morphological evolution of Flores Island, as commonly observed for volcanic islands, suggests (1) the balance between constructive processes (effusive and moderately explosive volcanic activities and tectonic uplifting movements) and destructive processes (marine abrasion, stream erosion, crater-forming volcanic explosions, caldera collapses and tectonic subsidence) and (2) the recurrent fluctuations of the sea-level. Records of (a) gaps in the volcanic activity and (b) erosional and depositional marine activity are shown as: - epiclastic deposits of marine origin - erosional morphologies, such as abrasion platforms, terraces, cliffs and caves - intensive palagonitization of the volcanic rocks - vertical changes of the structures in the hydroclastic submarine formations. Taking into account (1) the vertical crustal movements (uplift and subsidence) which may occur in volcanic domains and (2) the sequence of regressive-transgressive trends in the relative sea-level as expressed by indicators of pale-sea-levels, it is assumed that the morphological evolution of Flores Island comprehends three main stages, The existence of important differences between the present-day altitudes of correlated marine records noted in Flores, in Santa Marie Island (Azores Archipelago) and Porto Santo Island (Madeira Archipelago) is related with their crustal behaviour and different volcanic and tectonic evolution.

Speleogenesis on tectonically active carbonate islands, 2000, Gunn J. , Lowe D. J.
Studies of the geologically young, relatively porous limestones on Tongatapu Island in the Tongan archipelago suggest that the effect of dissolution at the interface between fresh and saline groundwater has been, and continues to be, crucial to the inception and development of underground conduits within young carbonate rock sequences. So far as it is possible to reconstruct the earliest speleogenetic events in the older preserved sequences on the nearby 'Eua Island, it appears that the processes that acted upon young reefal and back-reef carbonates during the Eocene were effectively the same as the processes that have acted on subsequent deposits and are still active today. It is commonly assumed that tectonism promotes the erosional removal of any early speleogenetic activity on carbonate islands and coasts. However, there is evidence on 'Eua to suggest that littoral cave systems and higher level conduits that target upon them, may survive gentle uplift, or even more extreme tectonism. This raises the possibility that some of the caves that can be explored today in both tropical and extra-tropical areas owe their origins to development of cavernous porosity in the littoral zone that was penecontemporaneous with rock formation.

Karst genetic model for the French Bay Breccia deposits, San Salvador, Bahamas., 2001, Florea L. , Mylroie J. , Carew J.
On the Island of San Salvador in the Bahama archipelago 30 breccia deposits can be found along the French Bay sea cliffs on the southeastern coast of the island. Breccia deposits of this type have not been observed on any other location on the island. These deposits have traditionally been interpreted as paleo-talus deposits from an eroding sea cliff formed on a transgressive eolianite deposited at the start of the oxygen isotope substage 5e sea-level highstand (ca. 125,000 years before present). New evidence supports a karst genesis. A survey of several deposits revealed a vertical restriction of +2 to +7 meters above sea level consistent with flank margin caves developed during the substage 5e still-stand. The morphologies of the features were found to be globular and contain distinct caliche boundaries, overhung lips, and smooth undulating bases. Petrographic results support a model in which voids are created and then infilled with a soil breccia. It can be concluded from these results that the deposits reflect qualities of a lithified soil breccia filling in breached flank margin caves. karst breccia, paleokarst, San Salvador

Relationships between morphology, genetics and geography in the cave fruit bat Eonycteris spelaea (Dobson, 1871) from Indonesia, 2003, Maharadatunkamsi, Hisheh S. , Kitchener D. J. , Schmitt L. H. ,
Morphological and genetic analyses of Eonycteris spelaea from 15 islands along the Banda Arc, from Sumatra to Timor and including Kalimantan and Sulawesi, revealed considerable divergence between islands and geographical patterning. On the basis of both morphology and genetics, the populations on the large islands of Greater Sunda (Sumatra, Java, Kalimantan and Sulawesi) are generally distinct from one another and from those on the islands in Nusa Tenggara (Lombok to Timor), which form a more cohesive cluster. These differences may be the result of the Nusa Tenggara populations having been colonized more recently than those on the Greater Sunda, and probably from a single source. All biological measures of the relationships between island populations are positively associated with the extent of the sea-crossing between them, indicating the sea is an important barrier to movement. Multivariate analyses show the presence of a marked trend for body size to increase from west to east. However, individuals from Kalimantan are not consistent with this trend, being smaller than predicted, and on the two outer Banda Are islands of Sumba and Timor animals are a little larger than predicted from the longitudinal trend. These differences could be due to the relative isolation of these populations or differing environmental conditions. There is also a negative relationship between body size and island area, but this is confounded by the longitudinal trend. No significant longitudinal trends in the genetic data were detected and the trend in body size may be an adaptive response to an environmental cline that is known to occur in this region. (C) 2003 The Linnean Society of London

Small karst features (karren) of Dugi otok island and Kornati archipelago coastal karst (Croatia), 2004, Perica Draž, En, Marjanac Tihomir, Anič, Ić, Branka, Mrak Irena, Jurač, Ić, Mladen

Dugi otok Island and Kornati archipelago islands are characterized by karst morphology. Small karst features are particulary well developed along the coast in the swash zone, and significant differences can be observed due to different interaction of wave action, bedding attitude, bed thicknesses and lithology. Among other karren types, fissure- and network-type karren are particulary interesting, both of which start developing from initial root karren. The age of some of these small karst features can be estimated by their occurrence in ancient quarries, and we suggest their historic age. We can envisage the future development of these small coastal corrosion forms.

The influence of the geological setting on the morphogenetic evolution of the Tremiti Archipelago (Apulia, Southeastern Italy), 2005, Andriani Gk, Walsh N, Pagliarulo R,
The Tremiti Archipelago (Southern Adriatic Sea), also called Insulae Diomedae from the name of the Greek hero who first landed there, is an area of high landscape and historical value. It is severely affected by significant geomorphologic processes dominated by mass movements along the coast that constitute the most important and unpredictable natural hazard for the population and cultural heritage. Coastal erosion is favoured by the peculiar geological and structural setting, seismic activity, weathering, development of karst processes, and wave action. The present paper reports on descriptive and qualitative evaluation of the factors controlling landslides and coastline changes based on medium-term in situ observation, detailed surface surveys at selected locations since 1995, and historic and bibliographic data. The Tremiti Archipelago is part of an active seismic area characterised by a shear zone separating two segments of the Adriatic microplate that have shown different behaviour and roll back rates in the subduction underneath the Apennines since middle Pleistocene. Although coastal morphology can be basically considered to be the result of wave action, the continual action of subaerial processes contributes effectively to the mechanism of shoreline degradation. Weathering mainly affects the marly calcisiltites and calcilutites of the Cretaccio Fm. and the friable and low cemented calcarenites and biomicrites of the San Nicola Fm. The cliffs are characterised by different types of failure such as lateral spreads, secondary topples, rock falls and slides. At the Isle of San Nicola, landslides are controlled by the contrast in competence, shear strength and stiffness between the Pliocene re-crystallised dolomitic calcarenites and calcisiltites and the Miocene marly calcilutites and calcisiltites. At the Isles of San Domino and Caprara rock falls are attributed to the undercutting of waves at the base of the cliffs

Results 1 to 15 of 31
You probably didn't submit anything to search for