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Types of meandering karren
Abstract
Morphological maps of a few meandering karren in Totes Gebirge have been made, and a range of meander parameters were measured. By using the terrain observations and the parameters of the meanders on the maps the development of the meanders can be explained and furthermore different types of meandering karren can be distinguished. © 2004 Gebrüder Borntraeger, D-14129 Berlin · D-70176 Stuttgart.
... Valuable field data on rillenkarren are gathered in Belloni andorombelli (1970), lundberg (1977a, b), Heinemann et al. (1977), Dunkerley (1979Dunkerley ( ), goudie et al. (1989, stenson and Ford (1993), Mottershead (1996a) and ginés (1996b), while measurements of clints and grikes are documented in goldie and cox (2000). The references on morphometry of rainpits are limited to lundberg (1977a) and ginés (1998b), and only scant quantitative data are reported from meandering runnels in Zeller (1967), Hutchinson (1996) and Veress and tóth (2004). Morphometric characteristics of trittkarren-trichterkarren features are discussed by Vincent (1983a) on the base of six morphological variables. ...
... The loops can not be ranked using the width of the meanderkarren zone alone since their values also depend on the width of the channel (Zeller 1967). Therefore Veress and tóth (2004) employed the idea of the width of the specific meanderkarren zone. They could calculate it from the equation as follows: ...
... using the morphology and the measured parameters of meanderkarren, Veress (2000b) and Veress and tóth (2004) classified them into the following types: "looping," "remnant," "developing," and "perishing" (Figure 7). Veress, 2000d). ...
... It is common that the lower end of the symmetric channel turns into asymmetric, thus, the lower part of the rinnenkarren transforms into meander karren [3] . Type III meander karren can occur on the floor of Type I channels [25] . Karren meanders may be looping, remnant, perishing and developing meanders [25] . ...
... Type III meander karren can occur on the floor of Type I channels [25] . Karren meanders may be looping, remnant, perishing and developing meanders [25] . ...
In this study, the development of rinnenkarren systems is analyzed. During the field studies, 36 rinnenkarren systems were investigated. The width and depth were measured at every 10 cm on the main channels and then shape was calculated to these places (the quotient of channel width and depth). Water flow was performed on artificial rinnenkarren system. A relation was looked for between the density of tributary channels and the average shape of the main channel, between the distance of tributary channels from each other and the shape of a given place of the main channel. The density and total length of the tributary channels on the lower and upper sections of the main channels being narrow at their lower end (11 pieces) and being wide at their lower end (10 pieces) of the rinnenkarren systems were calculated as well as their average proportional distance from the lower end of the main channel. The number of channel hollows was determined on the lower and upper sections of these main channels. It can be stated that the average shape of the main channel calculated to its total length depends on the density of the tributary channels and on the distance of tributary channels from each other. The main channel shape is smaller if less water flows on the floor for a long time because of the small density of the tributary channels and the great distance between the tributary channels. In this case, the channel deepens, but it does not widen. The width of the main channel depends on the number and location of the rivulets developing on channel-free relief. The main channel becomes narrow towards its lower end if the tributary rivulets are denser and longer on the upper part of the main rivulet developing on the channel-free, plain terrain and their distance is larger compared to the lower end. The channel hollows develop mainly at those places where the later developing tributary channels are hanging above the floor of the main channel. Thus, the former ones are younger than the latter ones. It can be stated that the morphology of the main channels (shape, channel hollows, and width changes of the main channel) is determined by the tributary channels (their number, location and age).
... Meanderkarren are channels with asymmetric cross section (Veress and Tóth 2004;Veress 2009b). The asymmetric cross section goes with the meandering ground plan of the feature only in the case of looping meanders ( Fig. 4.11a). ...
... The steep (often overhanging) and gentle slopes causing asymmetry alternate on the channel: the steep side is followed by a gentle one, then by a steep side again on the same side of the channel. Such karrenmeander types are the remnant meander ( Fig. 4.11c), the developing meander ( Fig. 4.11b) and the perishing meander (Veress and Tóth 2004;Veress 2009b). The asymmetric cross section is caused by the fact that the channel line of the water running down on the present or the former floor of karren meander was meandering or is meandering. ...
In this chapter, the karst landforms of glaciokarst are presented which are the following: karren, giant grikes, shafts, karst depressions such as giant depressions (dolines, uvalas), small-sized solution dolines, schachtdolines, subsidence dolines, ponors and poljes. We describe their distribution and frequency, their relation to glacial erosional features as well as the relation between each other, their size, morphology, varieties, evolution, development and development age.
... Meandering channels also form in bedrock where the driving processes include dissolution (e.g., Veress and Tóth, 2004;Allen, 1971;Zeller, 1967), abrasion by sediment particles (Sklar and Dietrich, 2004), plucking of bedrock (Chatanantavet and Parker, 2009;Whipple et al., 2000), slaking (Johnson and Finnegan, 2015), and weathering (Pelletier and Baker, 2011). ...
We present a set of observations on meltwater meandering rivulets on ice and compare them (qualitatively and quantitatively) to morphologies commonly found in meandering channels in different media. The observations include data from planned centimeter-scale experiments and from incidental self-formed millimeter-scale rivulets. Our data show pulsed lateral migration features, undercut banks and overhangs, meander bend skewness, and meander bend cutoffs. The data also compare well with planform characteristics of alluvial meandering rivers (sinuosity, wavelength-to-width ratios, and meander bend fatness and skewness). We discuss the (ir)relevance of scale in our experiments, which, in spite of being in the laminar flow regime and likely affected by surface tension effects, are capable of shedding light into the processes driving formation and evolution of supraglacial meltwater meandering channels. Our observations suggest that sinuosity growth in meltwater meandering channels on ice is a function of flow velocity and the interplay between vertical and lateral incision driven by temperature differences between flow and ice. In the absence of recrystallization (depositional analog to alluvial rivers), bends are more likely to be downstream-skewed and channels show lower sinuosities.
... Meandering channels also form in bedrock where the driving processes include dissolution (e.g. Veress and Tóth, 2004;Allen, 25 1971;Zeller, 1967), abrasion by sediment particles (Sklar and Dietrich, 2004), plucking of bedrock (Chatanantavet and Parker, 2009;Whipple et al., 2000), slaking (Johnson and Finnegan, 2015), and weathering (Pelletier and Baker, 2011). ...
We present a set of observations on meltwater meandering rivulets on ice and compare them (qualitatively and quantitatively) to morphologies commonly found in meandering channels in different media. The observations include data from planned centimeter-scale experiments, and from incidental self-formed millimeter-scale rivulets. Our data show pulsed lateral migration features, undercut banks and overhangs, meander bend skewness, and meander bend cutoffs. The data also compare well with planform characteristics of alluvial meandering rivers (sinuosity, wavelength-to-width ratios, and meander bend fatness and skewness). We discuss the (ir)relevance of scale in our experiments, which in spite of being in the laminar flow regime, and are likely affected by surface tension effects, are capable of shedding light into the processes driving formation and evolution of supraglacial meltwater meandering channels. Our observations suggest that sinuosity growth in meltwater meandering channels on ice is a function of flow velocity and the interplay between vertical and lateral incision driven by temperature differences between flow and ice. In the absence of recrystallization (depositional analog to alluvial rivers), bends are more likely to be downstream skewed and channels show lower sinuosities.
... Rinnenkarren develop only on bare surfaces, but according to Slabe and Liu (2009), they can develop under the cover too. Notches are special karren because the notches of meanderkarren are of flow origin (Veress and Tóth, 2004), while those which developed at the level of soil cover are of seepage origin (Jennings, 1985). However, notches can also develop along the water level (Jennings, 1985;Lundberg, 2009). ...
The karren formation and karren features of bare slopes is studied. The occurrence of various karren features was
measured on slopes with different inclination. The occurrence of various karren features on slopes has been
presented according to slope inclination values. The slopes were put into slope categories and their karren
features were given. Thus, the karren formation of the bare slopes of various karst types and karst features
(glaciokarst, coastal karst, tropical karst, mediterranean karst, collapse dolines, gorges, caves etc.) can be described.
It can be stated that on limestone with the increase of the inclination of the bearing slope, the diversity
of karren features decreases and those of flow origin will be increasingly dominant. However, with the increase
of slope inclination, features of flow origin will be increasingly simpler. On limestone, on slopes with a smaller
dip and on slopes of less soluble rocks, the distribution of karren features of seepage origin increases. On glaciokarst,
where bare slopes are widespread and of various inclination, karren are diverse and the distribution of
various types is also considerable. In other karst areas, small-inclined slopes (coastal karst, tropical karst) or very
large-inclined slopes (tropical karst, collapse dolines) are predominant and thus, the distribution of some karren
features (e.g. rinnenkarren) is limited. The change of slope inclination may result in the change of karren formation.
On glaciokarst, bare and subsoil karren formation are separated from each other, on mediterranean and
tropical karst, they are less separated from each other and the latter prepares the former. On halite, the effect of
slope inclination on karren formation may be modified by intensive dissolution. The karren formations of halite
and tropical karst are partly similar which can be explained by intensive dissolution in both cases.
... Unlike limestone runnel forms, for which there is some literature (e.g. Bögli, 1960;Veress, 2004), little morphometric analysis of sandstone runnels has been published. The studies of Wray (1995Wray ( , 1996 showed that individual runnels in Sydney region quartz sandstones often display characteristics of both rinnenkarren and rundkarren along their length; some sections of the runnel may be rinnenkarren-like with well-defined V-or U-shaped cross-sections and sharp rims, while other parts of the same runnel may be rundkarren-like and much more rounded and less distinct. ...
Quartz is considered one of the less soluble minerals of the Earth’s crust, and thus hardly affected by chemical weathering. Despite this, since more than forty years, it is clear that the formation of caves and peculiar solutional weathering dominated landforms in quartz-rich lithologies is common and shares several similarities to the well-known karstic ones in carbonate rocks. In the last thirty years great strides have been made in furthering our knowledge of the distribution of these forms around the world, and the geochemical processes involved. These studies have clearly shown that solutional weathering is a fundamental process, acting through interganular dissolution of quartz increasing the rock porosity and decreasing the rock strength to erosion. This process has been described in the concepts of ‘arenization’ and ‘phantomization’ and the widespread evidences of the fundamental role of quartz solution in landform genesis has even developed to the extent of several geomorphologists reassessing the definition of the term ‘karst’, and its application to these peculiar lithologies. Nonetheless the process is complicated by several factors, related both to environmental conditions (water chemistry and availability) as well as to the compositional and textural characters of the lithology (presence of clays, iron hydroxides, carbonate cement, etc.). All these aspects have to be taken carefully in consideration in order to understand if solution is a dominant or accessory process in the landscape evolution. In this review the state of knowledge on the relevant chemical processes, weathering mechanisms, and speleogenesis involved in the surface and underground karstification, and clear examples of quartz solution and solutional landforms from different world locations, are outlined and discussed.
Alguns dels edificis històrics de la Ciutat vella de Barcelona, Catalunya, presenten formes d'erosió fusiforme als carreus de les seves façanes.
S'han caracteritzat morfomètricament 324 formes a 10 façanes diferents sobre carreus tallats en pedra de Montjuïc. Addicionalment s'ha procedit a la caracterització en detall de les formes més representatives a partir d'un perfilador microtopogràfic.
Els resultats apunten que les formes d'erosió, la seva geometria i disposició, són un producte artificial, de caràcter antròpic. No es tracta de formes d'erosió associades a processos d'alteració químics o físics d'origen natural. A partir d'una revisió bibliogràfica a propòsit de formes semblants en altres contexts de la Mediterrània i d'Europa central, es proposa que aquestes formes d'incisió es corresponen amb marques de tall o d'esmolat d'atuells de metall.
The leading role of dissolution and the dominant subsurface drainage determine the special idiosyncrasy of karst geomorphology, with some notable variations depending on the type of soluble rock. The formation of karren is essentially related to the uneven or differential dissolution of the bedrock surface controlled by a number of factors, resulting in the development of depressions, clefts, channels, tubes, protruding features, and irregular patterns. Sinkholes or dolines are enclosed depressions with internal drainage widely regarded as one of the most characteristic landforms of karst landscapes. They are typically circular to subcircular in plan and show wide morphological diversity (cylindrical‐, conical‐, bowl‐, and pan‐shaped). In some cases, the variable geometry of the sinkholes can indicate different evolutionary stages and the relative age of the depressions. In nature, a complete spectrum between suffosion, collapse, and sagging sinkholes can be found in covered karst settings.
Solutional rills are classified and discussed by size, form and supposed mode of origin. The emphasis is on hydraulics of flow, the basic distinction being between channels parallel to the direction of low (the most common) and those which are transverse to flow (transverse ripples and fluted scallops). In nature few rills have had a simple history. Many must be classifed as polygenetic forms. -from Authors
Considering karst morphogenesis, there are no thresholds in the aqueous processes, but there are well-defined limits of mineral solubility. Because karst is rock specific and the other geomorphic systems are not, there is a situation of competition between karst processes and those of the zonal system. There is a threshold of effective competition which, if exceeded, results in other landforms or a polygenetic mix. Caves are the longest lived elements in our landscapes.-from Author
SUMMARY The distribution of meander channels in Switzerland is discussed with reference lo four examples of such channels in alluvial material, solid rock, glacier ice and limestone lapiès. The ranges of the main hydraulic particulars of such channels are set out in a Table, with comments. In a diagram representing over all regression curves for meander length and meander width the discussed meander types (ranges) are demonstrated. A point of special interest is that meanders are found in both the snbcritical and supei- critical ranges, with and without bed-load transportation, and with Reynolds' numbers ranging from very small to very large.
An hypothesis from which a general principle covering deformation of alluvial boundaries may be developed is proposed, namely—flow of fluid past a deformable boundary will deform the boundary so as to increase the resistance to flow. Upon attainment of a local maximum of resistance to flow the boundary shape will cease to change. Evidence from channel bed forms, meander geometry and armoured beds is presented to support the hypothesis. One implication of the hypothesis is that channels will adjust so that sediment movement is maximized. The authors would like geomorphologists to test this in their work on landscape evolution.