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Pronival (protalus) ramparts : a review of forms, processes, diagnostic criteria and palaeoenvironmental implications
  • Pronival (protalus) ramparts : a review of forms, processes, diagnostic criteria and palaeoenvironmental implications
  • Dynamique de versant ; Eau de fonte ; Moraine ; Mouvement de masse ; Neige ; Niche de nivation ; Paléoclimatologie ; Paléogéomorphologie ; Périglaciaire ; Rampart pronival ; Sédimentologie ; Terminologie
  • This article provides a critical review of ramparts by considering terminology, their morphology and sedimentological characteristics, possible mechanisms of formation, diagnostic criteria used to differentiate them from other landforms
Diagnostic criteria for pronival ramparts : site, morphological and sedimentological characteristics
  • Diagnostic criteria for pronival ramparts : site, morphological and sedimentological characteristics
  • Geomorphogenesis ; Glacial features ; Inheritated geomorphological features ; Palaeo-environment ; Periglacial features ; Pronival rampart ; Sedimentology ; Terminology
  • Pronival ramparts are often confused with moraines, protalus rock glaciers or rock-slope failure debris accumulations. Various characteristics have been suggested for identification of pronival ramparts but these are derived largely from relict
  • of actively accumulating features. A more robust set of criteria, derived from common characteristics of actively accumulating ramparts, are proposed that assists in discriminating relict and active pronival ramparts from other discrete bedrock cliff-foot
  • features. Research on actively accumulating ramparts has shown that some of the suggested criteria are no longer useful. This paper reviews existing criteria and shows that, for diagnostic purposes, more emphasis should be placed on the attributes
Snowpatch hollows and pronival ramparts in the Krkonoše Mountains, Czech Republic : distribution, morphology and chronology of formation
  • Snowpatch hollows and pronival ramparts in the Krkonoše Mountains, Czech Republic : distribution, morphology and chronology of formation
  • Czech Republic ; Geochronology ; Holocene ; Lateglacial ; Mountain ; Nivation hollow ; Periglacial features ; Pollen diagram ; Pronival rampart ; Snow ; Spatial distribution
  • Two types of landforms attributed to the geomorphological effects of long-lasting snow accumulations, snowpatch hollows and pronival ramparts, were studied in the Krkonoše Mountains, Czech Republic. Factors influencing the distribution
  • and morphology of snowpatch hollows were examined using statistical analysis of field-measured and DEM-modelled snowpatch hollow characteristics. Snowpatch hollows were classified into two groups. The age and degree of activity of pronival ramparts, occurring
  • only at two sites in the study area, were determined using several methods (Schmidt hammer, lichenometry, pollen analysis, and radiocarbon dating). The appearance of these pronival ramparts differs between the two sites as a result of the different
Snow-push processes in pronival (protalus) rampart formation : geomorphological evidence from Smørbotn, Romsdalsalpane, southern Norway
  • Snow-push processes in pronival (protalus) rampart formation : geomorphological evidence from Smørbotn, Romsdalsalpane, southern Norway
  • Dépôt de pente ; Moraine ; Neige ; Norvège ; Pro-talus rampart ; Périglaciaire ; Sédimentologie
Some observations on the formation of an active pronival rampart at Grunehogna Peaks, Western Dronning Maud Land, Antarctica
  • Some observations on the formation of an active pronival rampart at Grunehogna Peaks, Western Dronning Maud Land, Antarctica
  • Summer observations of the morphology and the debris accumulation processes at an actively forming pronival rampart at Grunehogna Peaks, Western Dronning Maud Land, demonstrate that rockfall debris accumulation is causing downslope (outward) rampart
  • extension even though the distal slope is not at the angle of repose. Field experiments show that the vast majority of rocks can traverse a stable firn surface to reach the proximal slope of the rampart and more than half end up on the distal slope or beyond
  • . The formation processes indicate that the morphological characteristics and environmental conditions under which such features develop may be more varied than conceived in current models. Consequently, caution must be employed when fossil ramparts are used
A relict pronival (protalus) rampart in the Tararua Range, North Island, New Zealand
  • A relict pronival (protalus) rampart in the Tararua Range, North Island, New Zealand
  • Inheritated geomorphological features ; Moraine ; Mountain ; New Zealand ; North Island ; Palaeo-environment ; Periglacial features ; Pronival rampart ; Snow
  • . Instead, the AA. interpret the ridge as a pronival (protalus) rampart formed by supranival debris supply–from the ca. 200 m-high southeastern slopes of Dundas Ridge–across a snowbed. Re-distribution of snow by prevailing westerlies from Mt Dundas Ridge
Little Ice Age glaciers in the Balkans : low altitude glaciation enabled by cooler temperatures and local topoclimatic controls
  • ) examine the timing of moraine and pronival rampart building in these high cirques using lichenometry; 3) reconstruct the characteristics of the former glaciers and snow patches and assess the local topoclimatic controls (windblown and avalanching snow
Izmenčivost' vysotnogo položeniâ firnovoj linii na lednikah Altae-Saânskoj gornoj strany i eë svâz' s klimatičeskimi parametrami
  • Air temperature ; Altai Mountains ; Altitude ; Asian part of Russia ; Climatic index ; Firn ; Glacier ; Precipitation ; Pronival rampart ; Saian Mountains ; Siberia
Some observations concerning the morphology and sedimentology of a protalus rampart, Okstindan, Norway
  • Some observations concerning the morphology and sedimentology of a protalus rampart, Okstindan, Norway
  • Actuel ; Géographie physique ; Nivation ; Norvège ; Protalus rampart ; Périglaciaire ; Rempart de nivation ; Sédimentologie
Protalus Ramparts on Navajo Mountain, Utah, USA : reinterpretation as blockslope-sourced rock glaciers
  • Protalus Ramparts on Navajo Mountain, Utah, USA : reinterpretation as blockslope-sourced rock glaciers
  • Here the AA. report the results of field reinvestigation of the Navajo Mountain ridges, designed to evaluate the validity of their interpretation as protalus ramparts, and discuss possible alternative origins for these landforms.
Protalus ramparts and the altitude of the local equilibrium line during the last glacial stage in Bokspruit, East Cape Drakensberg, South Africa
  • Protalus ramparts and the altitude of the local equilibrium line during the last glacial stage in Bokspruit, East Cape Drakensberg, South Africa
  • A ridge of unconsolidated debris at an altitude of 2000 m, located beneath cliffs in the East Cape Drakensberg of South Africa, is interpreted on morphological and sedimentological evidence as a protalus rampart. The rampart is believed to have
Neoglacial climatic inferences from rock glaciers and protalus ramparts, southern Lemhi Mountains, Idaho
  • Neoglacial climatic inferences from rock glaciers and protalus ramparts, southern Lemhi Mountains, Idaho
  • The more widespread protalus ramparts were useful for examining the importance of microsites in the northern and southern portions of the range. In the north, the climate was sufficiently severe to produce favorable microclimates for protalus
  • development. Farther south, the less severe climate required a climatic deterioration of regional significance before protalus ramparts could develop.
The characteristics and significance of some lateglacial protalus ramparts in upland Britain
  • The characteristics and significance of some lateglacial protalus ramparts in upland Britain
  • Géographie physique ; Nivation ; Paléo-environnement ; Paléogéographie ; Protalus rampart ; Périglaciaire ; Quaternaire zones moyennes ; Rempart de nivation ; Royaume-Uni ; Scotland ; Tardiglaciaire
A protalus rampart related to alpine debris flows in the Kuranosuke cirque Northern Japanese Alps
  • A protalus rampart related to alpine debris flows in the Kuranosuke cirque Northern Japanese Alps
Remnants of periglacial mounds in the Hautes Fagnes (Belgium): structure and age of the ramparts
  • Remnants of periglacial mounds in the Hautes Fagnes (Belgium): structure and age of the ramparts
Internal structure and geological context of ramparted depressions, Llanpumsaint, Wales
  • Internal structure and geological context of ramparted depressions, Llanpumsaint, Wales
  • The AA. present detailed sedimentological and geophysical investigations of ramparted depressions from Llanpumsaint, Wales. These data are used to establish internal structure and to evaluate possible mechanisms for landform formation. Borehole
  • and geophysical data have revealed a thick sequence of glaciolacustrine sediments beneath the study site. The rampart deformation structures are consistent with 2 models, but units of sand and gravel within the ramparts favour a hypothesis that these landforms
  • represent the collapsed remains of ground-ice mounds. This study highlights the importance of recognising and evaluating all possible (periglacial and non-periglacial) models for the development of ramparted depressions.
Lodowce gruzowe i waly niwalne - efekt późnoglacjalnej ewolucji rzeźby Tatr
  • This article introduces an analysis of two examples of cryogenic landforms - a rock glacier and a protalus rampart in the high-mountain zone of the Tatra Mountains. Field geomorphological research and airphoto interpretation helped
  • processes during the last glaciation. The most spectacular protalus ramparts have been recognised in areas representing remnants of the preglacial rather that the glaciated Tatra landscape (i. e. Liptovské kopy). The characteristics of these forms
  • are similar to the protalus ramparts described in European, Japanese and North American mountains. - (BJ)
Some observations regarding protalus ramparts
  • Some observations regarding protalus ramparts
A protalus rampart from the western Mourne mountains, Northern Ireland
  • A protalus rampart from the western Mourne mountains, Northern Ireland
The side growth of lithalsas : some comments on observations in Northern Québec
  • Based on observations in northern Québec and Belgium, the author infers that lithalsas in northern Québec are modern analogues of the enclosed and ramparted depressions that occur on the Hautes Fagnes plateau, Belgium. It is hypothesised