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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. ...

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. ...

Speleology in Kazakhstan

Shakalov on 11 Jul, 2012
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 ground-water barrier is rock or artificial material which has a relatively low permeability and which occurs below the land surface where it impedes the movement of ground water and consequently causes a pronounced difference in the potentiometric surface on opposite sides of it [22].?

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Karst environment, Culver D.C.
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Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
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Your search for mouth (Keyword) returned 21 results for the whole karstbase:
Showing 1 to 15 of 21
The `human revolution' in lowland tropical Southeast Asia: the antiquity and behavior of anatomically modern humans at Niah Cave (Sarawak, Borneo), , Barker G, Barton H, Bird M, Daly P, Datan I, Dykes A, Farr L, Gilbertson D, Harrisson B, Hunt C,
Recent research in Europe, Africa, and Southeast Asia suggests that we can no longer assume a direct and exclusive link between anatomically modern humans and behavioral modernity (the `human revolution'), and assume that the presence of either one implies the presence of the other: discussions of the emergence of cultural complexity have to proceed with greater scrutiny of the evidence on a site-by-site basis to establish secure associations between the archaeology present there and the hominins who created it. This paper presents one such case study: Niah Cave in Sarawak on the island of Borneo, famous for the discovery in 1958 in the West Mouth of the Great Cave of a modern human skull, the `Deep Skull,' controversially associated with radiocarbon dates of ca. 40,000 years before the present. A new chronostratigraphy has been developed through a re-investigation of the lithostratigraphy left by the earlier excavations, AMS-dating using three different comparative pre-treatments including ABOX of charcoal, and U-series using the Diffusion-Absorption model applied to fragments of bones from the Deep Skull itself. Stratigraphic reasons for earlier uncertainties about the antiquity of the skull are examined, and it is shown not to be an `intrusive' artifact. It was probably excavated from fluvial-pond-desiccation deposits that accumulated episodically in a shallow basin immediately behind the cave entrance lip, in a climate that ranged from times of comparative aridity with complete desiccation, to episodes of greater surface wetness, changes attributed to regional climatic fluctuations. Vegetation outside the cave varied significantly over time, including wet lowland forest, montane forest, savannah, and grassland. The new dates and the lithostratigraphy relate the Deep Skull to evidence of episodes of human activity that range in date from ca. 46,000 to ca. 34,000 years ago. Initial investigations of sediment scorching, pollen, palynomorphs, phytoliths, plant macrofossils, and starch grains recovered from existing exposures, and of vertebrates from the current and the earlier excavations, suggest that human foraging during these times was marked by habitat-tailored hunting technologies, the collection and processing of toxic plants for consumption, and, perhaps, the use of fire at some forest-edges. The Niah evidence demonstrates the sophisticated nature of the subsistence behavior developed by modern humans to exploit the tropical environments that they encountered in Southeast Asia, including rainforest

Frustration and New Year Caves and Their Neighbourhood, Cooleman Plain, N.S.W., 1977, Rieder L. G. , Jennings J. N. , Francis G.

Frustration and New Year Caves are active between-caves, paralleling in plan and profile the ephemeral stream bed of the V-shaped valley in which their entrances are found. The main streamsink in this valley system feeds their stream, which in turn supplies Zed Cave, a short outflow cave just outside the mouth of this valley. This modest derangement of surface drainage pattern is in keeping with the caves which show slight vadose modification of epiphreatic cave development. Although these active caves are young, they probably formed prior to a Late Pleistocene cold period (30,000 to 10,000 BP) on the basis of soils evidence. Clown Cave on the brow of the valley, a dry cave with indications of sluggish phreatic development, is related to a planation phase of Middle or Lower Tertiary age before valley incision. Bow and Keyslot Caves are abandoned in and out and outflow caves respectively, formed when the surface stream channel was a few metres above the present valley bottom so they antedate the active river caves a little. This hydrologically independent part of the Cooleman Plain mirrors in most respects the major parts draining to the Blue Waterholes, differing chiefly in the greater proportion of between-caves discovered so far.


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.

SOUTHERN AFRICA AND MODERN HUMAN ORIGINS, 1992, Deacon Hj,
This paper argues that southern Africa was a remote part of the Old World in the late Pleistocene (125-10 ka ago). Because of this isolated position there was continuity without significant replacement in the resident population. Isolation and the relatively recent spread of agriculture to the region has allowed a section of this population to survive into the present. They are the Bushmen (San). Studies of geographic patterning in conventional genetic markers and mitochrondrial DNA indicate that the Bushman clade has a long evolutionary history in southern Africa. Estimates of more than 100 ka for the continued presence of this population in the region are supported in archaeological investigations of sites with long sequences such as Klasies River main site and Border Cave. Human remains dating to the earlier part of the late Pleistocene have been recovered from these sites and the samples form a morphological series with the Klasies River remains possibly 20 ka older than those from Border Cave. There is no fossil record for the later Pleistocene, however, at a period when selection for a gracile morphology may have been pronounced. The cultural associations in the earlier late Pleistocene are with the Middle Stone Age. Expressions of cultural 'style' and the occurrence of similar artefact design types in the Middle and Later Stone Ages can be interpreted with reference to the ethnographic present. Temporal continuity can be shown in the geographical distribution of stylistic markers and this suggests participation in a shared cognitive system. The inference is that the people in the earlier late Pleistocene had cognitive abilities that are comparable to those shown by their Holocene and modern descendants. The presence of the ancestors of a modern population in the earlier late Pleistocene in this region is perhaps expected if modern people had their origins in Africa

Two Caves in Plymouth in 1744 and 1773, 1993, Shaw T. R.

Some remarks on the genus Microcharon Karaman in Greece, and description of M. agripensis n. sp. (Crustacea, Isopoda, Microparasellidae), 1994, De Laurentiis Paola, Galassi Diana M. P. , Pesce Giuseppe L.
Several samples of microparasellid isopods of the genus Microcharon Karaman were obtained in groundwater habitats of Greece. Four species are identified, and taxonomical and zoogeographical remarks on some rare or poorly known taxa are made. One species, herein described as Microcharon agripensis n. sp., is new to Science. M. latus prespensis Karaman, 1954, on account of the different morphology of the first and second male pleopods, and its partially overlapping distribution, in respect to M. latus Karaman, 1934, is definitively raised at specific rank. Supplementary descriptions and illustrations are reported for incompletely described species such as M. latus, M. prespensis stat. nov., M. major Karaman, 1954 and M. othrys Argano & Pesce, 1979. For some species, such as M. latus, M. othrys and M. antonellae Galassi, 1991, SEM preparations of the mouthparts, not well detailed with the optical microscopy, were carried out. According to data from the present study, a paleogeographical scenario of the Balkan Peninsula is briefly depicted in order to sketch the most significative events which led to the colonization and speciation of the Microcharon species in this area.

Morphological affinities of the proximal ulna from Klasies River main site: Archaic or modern?, 1996, Churchill Se, Pearson Om, Grine Fe, Trinkaus E, Holliday Tw,
The Middle Stone Age (MSA) asociated hominids from Klasies River Mouth (KRM) have taken on a key role in debate about the origins of modern humans, with their craniofacial remains seen as either representing the earliest well-dated modern humans in southern Africa or orthognathic late archaic humans. Diagnostic postcranial remains from Klasies are few, but one specimen-a proximal right ulna from the lower SAS member-is useful For assessing the morphological affinities of these hominids. Canonical variates analysis using 14 proximal ulnar dimensions and comparative data from European, west Asian and African archaic humans, and Levantine Mousterian, European Upper Paleolithic, African Epipaleolithic and diverse recent modern human samples (many of recent African descent) were employed to assess the morphological affinities of this specimen. Results suggest an archaic total morphological pattern for the Klasies ulna. Analysis of diaphyseal cross-sectional geometry reveals an ulnar shaft with relatively thick cortical bone, but the specimen cannot be readily distinguished from Neandertals or early anatomically modem humans on the basis of shaft cross-sectional properties. If the isolated ulna from Klasies is indicative of the general postcranial morphology of these hominids, then the MSA-associated humans from KRM may not be as modern as has been claimed from the craniofacial material. It ii: possible also that the skeletal material from KRM reflects mosaic evolution-retention of archaic postcranial characteristics. perhaps indicating retention of archaic habitual behavior patterns, in hominids that were becoming craniofacially modern. (C) 1996 Academic Press Limited

Morphology of the border cave hominid ulna and humerus, 1996, Pearson O. M. , Grine F. E. ,
Hominid bones from Border Cave (BC) have been the subject of controversy with regard to the question of modern human origins. New dating assays suggest that while some of the BC remains are of comparatively recent age (i.e. < 20 kyr), several postcranial fragments derive from the Middle Stone Age (MSA) layers. Among the latter, a proximal ulna in comparable to one from the MSA at Klasies River Mouth, in that both have an archaic pattern of morphology in the relative height of the coronoid and olecranon processes. This configuration appears to characterize Neandertals, and is displayed also by more ancient African ulnae. The BC humeral diaphysis has moderately thick cortical bone, but us otherwise unremarkable. The proximal ulnar morphology might suggest that the MSA inhabitants of South Africa engaged in activities similar to those of Neandertals and other postcranially archaic hominids. If the modern-looking BC-1 cranium in contemporaneous with the BC postcranial bones, this would bear testament to the mosaic nature of human evolution. Alternatively, if BC-1 proves to be of recent derivation, and the postcrania are as old as the base of the BC MSA sequence has been claimed to be (c. 195 kyr), they might have been associated with more archaic crania (perhaps similar to Florisbad). Final resolution of these questions awaits determination of the absolute ages of the BC-1 cranium and the BC postcranial bones

Application of morphometric relationships to active flow networks within the Mammouth Cave Watershed, MSc Thesis., 2001, Glennon, A.

Numerous quantitative relationships have been formulated to describe the nature of surface-drainage networks. These parameters have been used in various studies of geomorphology and surface-water hydrology, such as flood characteristics, sediment yield, and evolution of basin morphology. Little progress has been made in applying these quantitative descriptors to karst flow systems due to the lack of sufficiently complete data and inadequate technology for processing the large, complex data sets. However, as a result of four decades of investigation, an abundance of data now exists for the Mammoth Cave Watershed providing the opportunity for broader quantitative research in the organization of a large, highly-developed, karst-drainage network. Developing Geographic Information System (GIS) technology has provided tools to 1) book-keep the karst system's large, complex spatial data sets, 2) analyze and quantitatively model karst processes, and 3) visualize spatially and temporally complex data. []Karst aquifers display drainage characteristics that in many ways appear similar to surface networks. The purpose of my research was to explore techniques by which quantitative methods of drainage-network analysis can be applied to the organization and flow patterns in the Turnhole Bend Groundwater Basin of the Mammoth Cave Watershed. []Morphometric analysis of mapped active base-flow, stream-drainage density within the Turnhole Bend Groundwater Basin resulted in values ranging from 0.24 km/km2 to 1.13 km/km2. A nearby, climatologically similar, nonkarst surface drainage system yielded a drainage density value of 1.36 km/km2. Since the mapped cave streams necessarily represent only a fraction of the total of underground streams within the study area, the actual subsurface values are likely to be much higher. A potential upper limit on perennial drainage density for the Turnhole Bend Groundwater Basin was calculated by making the assumption that each sinkhole drains at least one first-order stream. Using Anhert and Williams’ (1998) average of 74 sinkholes per km2 for the Turnhole Bend Groundwater Basin, the minimum flow-length draining one km2 is 6.25-7.22 km (stated as drainage density, 6.25-7.22 km/km2). []Stream ordering of cave streams and their catchments generally follow Hortonian relationships observed for surface-stream networks. Subsurface streams within the Mammoth Cave Watershed generally exhibit a converging, dendritic pattern and possess drainage basins proportionately large for their order. However, even at base-flow conditions, the Turnhole Bend drainage system continues to possess confounding characteristics. These include at least one leakage to an adjacent groundwater basin (Meiman et al., 2001), diverging streams sharing the same surface catchment (Glennon and Groves, 1997), and highly complex, three-dimensional basin boundaries (Meiman et al., 2001). In spite of the incomplete data set available for the Mammoth Cave Watershed, study of initial values suggests an orderly subsurface flow network with numerical results that allow for comparison of the karst-flow network to surface fluvial systems.


Seismic stratigraphy of Late Quaternary deposits from the southwestern Black Sea shelf: evidence for non-catastrophic variations in sea-level during the last ~10[punctuation space]000 yr, 2002, Aksu Ae, Hiscott Rn, Yasar D, Isler Fi, Marsh S,
Detailed interpretation of single channel seismic reflection and Huntec deep-tow boomer and sparker profiles demonstrates that the southwestern Black Sea shelf formed by a protracted shelf-edge progradation since the Miocene-Pliocene. Five seismic-stratigraphic units are recognized. Unit 1 represents the last phase of the progradational history, and was deposited during the last glacial lowstand and Holocene. It is divided into four subunits: Subunit 1A is interpreted as a lowstand systems tract, 1B and 1C are interpreted as a transgressive systems tract, and Subunit 1D is interpreted as a highstand systems tract. The lowstand systems tract deposits consist of overlapping and seaward-prograding shelf-edge wedges deposited during the lowstand and the subsequent initial rise of sea level. These shelf-edge wedges are best developed along the westernmost and easternmost segments of the study area, off the mouths of rivers. The transgressive systems tract deposits consist of a set of shingled, shore-parallel, back-stepping parasequences, deposited during a phase of relatively rapid sea-level rise, and include a number of prograded sediment bodies (including barrier islands, beach deposits) and thin veneers of seismically transparent muds showing onlap onto the flanks of older sedimentary features. A number of radiocarbon dates from gravity cores show that the sedimentary architecture of Unit 1 contain a detailed sedimentary record for the post-glacial sea-level rise along the southwestern Black Sea shelf. These data do not support the catastrophic refilling of the Black Sea by waters from the Mediterranean Sea at 7.1 ka postulated by [Ryan, Pitman, Major, Shimkus, Maskalenko, Jones, Dimitrov, Gorur, Sakinc, Yuce, Mar. Geol. 138 (1997) 119-126], [Ryan, Pitman, Touchstone Book (1999) 319 pp.], and [Ballard, Coleman, Rosenberg, Mar. Geol. 170 (2000) 253-261]

The influence of hydroelectrical development on the flow regime of the karstic river Cetina, 2003, Bonacci O, Rojebonacci T,
The Cetina River is a typical karst watercourse in the deep and well-developed Dinaric karst. The total length of the Cetina River open streamflow from its spring to the mouth is about 105 km. Estimated mean annual rainfall is 1380 mm. The Cetina catchment is built of Triassic, Jurassic, and Cretaceous carbonate strata. The western part of the catchment by the Cetina River is referred to as the 'direct' or topographic catchment. It was defined based on surface morphologic forms, by connection between mountain chain peaks. This part of the catchment is almost entirely situated in the Republic of Croatia. The eastern part of the catchment is referred to as the 'indirect' catchment, and is mainly situated in Bosnia-Herzegovina. Water from the 'indirect' catchment emerges from the western 'direct' catchment in numerous permanent and temporary karst springs. Since 1960, numerous hydrotechnical works have been carried out on the Cetina River and within its catchment. Five hydroelectric power plants (HEPPs), five reservoirs, and three long tunnels and pipelines have been built. Their operation has significantly altered the natural hydrological regime. The Cetina River is divided into two hydrological reaches. In the 65 km upstream, the hydrological regime was redistributed within the year: low flows had increased and high flows had decreased, although the mean annual discharge remained the same. Part of the Cetina watercourse downstream from the Prancevici Reservoir lost the majority of its flow. The mean annual discharges dropped from 100 m(3) s(-1) to less than 10 m(3) s(-1) because of the Zakucac HEPP development. Copyright (C) 2003 John Wiley Sons, Ltd

Post-Miocene stratigraphy and depositional environments of valley-fill sequences at the mouth of Tampa Bay, Florida, 2003, Ferguson Tw, Davis Ra,
Post-Miocene sea-level low stands allowed rivers and karst processes to incise the exposed carbonate platform along the Gulf Coast of Florida. Few Miocene to mid-Pleistocene deposits survived erosion along the present coast except within incised valleys. Since their formation, these valleys have been filled and incised multiple times in response to sea-level changes. The thick sedimentary sequences underlying the mouth of Tampa Bay have been recorded as a range of depositional environments and multiple sea-level incursions and excursions during pre-Holocene time and subsequent to the accumulation of the Miocene carbonate sequences. Sediment analysis of cores collected from a north-south transect across the mouth of Tampa Bay has enabled the identification of lithofacies, ranging from well-sorted, quartz sand to dense, fossiliferous, phosphatic grainstone. These facies were deposited in freshwater, estuarine, and shallow, open marine environments. As a result of channel development and migration within the paleovalley, and cut-and-fill associated with individual transgressions and regressions, correlation of the lithofacies does not extend across the entire transect. Fining-upward sequences truncated by tidal ravinement surfaces that extend throughout the paleovalley can, however, be identified. Age determinations based on 14-C analysis, amino-acid racemization, and strontium isotope analysis dating of numerous samples yield ages of Miocene, Pliocene, early Pleistocene, and late Pleistocene, as well as Holocene for sequences that accumulated and were preserved in this valley-fill complex. Numerous inconsistencies in the stratigraphic organization of the age determinations indicate that there are bad dates, considerable reworking of shells that were dated, or both. For this reason as well as the lack of detailed correlation among the three relatively complete cores, it is not possible to place these strata in a sequence stratigraphic framework. (C) 2003 Elsevier B.V. All rights reserved

The Danube submarine canyon (Black Sea): morphology and sedimentary processes, 2004, Popescu Irina, Lericolais Gilles, Panin Nicolae, Normand Alain, Dinu Cornel, Le Drezen Eliane,
The Danube Canyon is a large shelf-indenting canyon that has developed seaward of the late Pleistocene paleo-Danube valley. Mechanisms of canyon evolution and factors that controlled it are revealed by analyzing the morphology and the sedimentary structure of the canyon, as well as the main features of the continental margin around the canyon. This is based on investigation by swath bathymetry in the canyon area combined with different types of seismic data.The canyon is a major erosional trough with a flat bottom cut by an entrenched axial thalweg. The thalweg path varies from highly meandering to fairly straight in relation to the local gradient. Segments of the canyon are characterized by specific morphology, orientation and gradient along the axial thalweg. We interpret these segments in terms of canyon maturity. The sedimentary structure of the canyon documents an older phase of erosion followed by partial infilling, and thus attests for repeated cycles of canyon development.Canyon morphology is interpreted as a result of erosive sediment flows along the entrenched axial thalweg that caused downcutting into the canyon bottom and instability of the canyon walls, and hence enlargement of the canyon and expansion by headward erosion. During the last lowstand level of the Black Sea the canyon was located in an area of high sediment supply close to the paleo-Danube River mouths. This is indicated by buried fluvial channels on the shelf and by a wave-cut terrace associated with a water level situated about -90 m below the present level. We infer that erosive flows in the canyon resulted from hyperpycnal currents at the river mouths, probably favored by the low salinity environment that characterized the Black Sea during lowstand times. Other mechanisms could have contributed to trigger sediment failure along the canyon, such as instability related to the presence of shallow gas, or the effect of a deep fault

Unattached fraction of radon decay products as a crucial parameter for radon dosimetry in Postojna Cave, 2004, Vaupotič, Janja, Kobal I Van

Short-term summer and winter monitoring was carried out at the lowest point in Postojna cave, on air concentrations on radon (CRn) and radon decay products (CRnDP), the equilibrium factor (F) and unattached fraction of radon decay products (fun), barometric pressure (P), relative air humidity in the cave (RH) and air temperature outside (Tout) and in the cave (Tin), with the emphasis on fun. Dose conversion factors (DCF) for mouth and nasal breathing were calculated from the fun values (ranging from 0.10 to 0.68) and effective doses for the employees in the cave were obtained. These significantly exceed the doses based on the ICRP-65 methodology now in use.


The Mouth of Slaughter Canyon, 2006, Alton Brown

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