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Clast size variations on talus : some observations from northwest Ireland

Clast size variations on talus : some observations from northwest Ireland
Reports observations relating to both lateral and longitudinal variations in the size of talus clasts in northwest Ireland. The implications of these patterns, along with aspects of slope morphology, for talus slope development are then discussed.

The structure and sedimentology of relict talus, Trotternish, Northern Skye, Scotland

The structure and sedimentology of relict talus, Trotternish, Northern Skye, Scotland
Coulée boueuse ; Datation C 14 ; Dynamique de versant ; Granulométrie ; Ravinement ; Royaume-Uni ; Scotland ; Sédimentologie ; Talus ; Transport sédimentaire ; Versant
This paper reports the results of research on the internal structure and sedimentology of a relict talus slope on the Trotternish Peninsula, northern Skye, Scotland. Particular attention is devoted to : describing and interpreting the internal
structure of the talus; and establishing the origin of the fine fraction within the talus debris. The implications of these findings for talus slope evolution are then considered.

Permafrost distribution in talus slopes located within the alpine periglacial belt, Swiss Alps

Permafrost distribution in talus slopes located within the alpine periglacial belt, Swiss Alps
Alpes ; Distribution spatiale ; Géophysique ; Montagne ; Pergélisol ; Périglaciaire ; Suisse ; Talus d'éboulis ; Température du sol
The extent of permafrost in 9 talus slopes located within the alpine periglacial belt in the western Swiss Alps was investigated using ground surface temperature measurements and one-dimensional geoelectrical profiles. The cooling of the ground
in the lower parts of some of the talus slopes investigated was apparently due to the chimney effect. It is inferred that this mechanism plays an important role in permafrost development in the lower half of talus slopes located within the discontinuous

Properties of talus slopes composed of flat blocks

Properties of talus slopes composed of flat blocks
Dynamique de versant ; Eboulement ; Glissement de terrain ; Granulométrie ; Norvège ; Talus d'éboulis ; Versant
Grain size distribution ; Landslide ; Norway ; Rockfall ; Slope ; Slope dynamics ; Talus slope
In this paper the AA. draw attention to a rarer kind of talus slopes, the ones mostly formed by flat stones as building blocks. One case study in Norway is examined as an example typifying the properties of flat-blocks taluses. From comparisons
of the geometrical characteristics and grain size distribution with taluses of the same rock type formed by regular blocks, remarkable differences are found, especially concerning the slope angle and the size distribution of blocks as a function of the distance from
the headwall. To understand the formation dynamics of flat-block taluses, the AA. also carried out some simple experiments with flat blocks falling onto an experimental board.

Factors affecting sedimentary outflow from talus slope by debris flow : a laboratory experiment

Factors affecting sedimentary outflow from talus slope by debris flow : a laboratory experiment
To examine running distance of debris flows occurring on the talus slopes, rainfall experiments were carried out. The quantity Vt is defined as the reciprocal of the threshold value of Lc/Lt at which debris flows just reach the bottom of the talus
slope, where Lc is the horizontal length of the cliff and Lt is the horizontal length of the talus slope. The value of Vt is also a measure of the possibility of sedimentary outflow from the talus slope by debris flow. The value of Vt shows strong
correlation with the hydraulic conductivity of talus sediment (K) and the rainfall intensity (It). The outflow of debris from the talus slope can be predicted using the values of Lc, Lt, K, and It.

Fractal techniques and the surface roughness of talus slopes : a comment and reply

Fractal techniques and the surface roughness of talus slopes : a comment and reply
Andrle and Abrahams (1989) present the results of a rigourous test of self-similarity on profiles and transects obtained from talus slopes. The aim of their paper is to show that the self-similar fractal model (SSFM) is of limited usefulness
in describing the roughness of talus slopes and presumably of other geomorphic features. But several issues raised by the AA. require further discussion.

Materikovyj sklon kak planetarnaja morfostruktura (Le talus continental, morphostructure planétaire)

Materikovyj sklon kak planetarnaja morfostruktura (Le talus continental, morphostructure planétaire)
Glacis continental ; Géographie physique ; Géomorphologie structurale ; Marge continentale ; Talus continental ; Typologie

Surficial talus fabric and particle gliding over snow on Lassen Peak, California

Surficial talus fabric and particle gliding over snow on Lassen Peak, California
This paper reports on the fabric of experimental clasts initially stopping on snow-covered talus and later deposited on the slope surface after the seasonal shrinking of the snowbank. Its main purpose is to ascertain whether fabrics developed
on the snow surface can be retained after ablation onto the underlying talus| the fabrics attained by these particles will also be compared with those of clasts found in situ on a nearby talus.

Evoljucija i vozrast osypej flisevogo nizkogor'ja Kryma (Evolution de l'âge des éboulis dans les basses montagnes de flysch de la Crimée)

Forms and age of talus base are described for eroded and uneroded scree slopes. Uneroded talus base profile is reconstructed using Lehman equation and appeared to be similar to measured profile. Eroded talus base profiles can be convex, concave
, convex-concave, concave-convex and rectilinear. Equations are given which were used for calculation of 25 talus and their base age (under assumption of parallel retreat of scree slope). Average denudation rate for the slope estimated by means
of dendrochronology appeared to be 13,6 mm per year. Uneroded talus age corresponds to the age of its base and that of the scree slope. Eroded talus are younger than their base and far younger than the scree slope.

Les ruptures de pente dans les terres cultivées: étude du phénomène en Andalousie

Andalucia ; Erosion anthropique ; Espagne ; Formation ; Géographie de l'Europe ; Géographie rurale ; Morphologie agraire ; Parcellaire ; Paysage ; Paysage rural ; Rideau ; Rupture de pente ; Structure agraire ; Talus ; Talus intra-parcellaire
L'article est illustré de photographies très parlantes| il vérifie, selon son A., la théorie de L. Aufrère, selon laquelle ces talus n'ont pas de cause naturelle et naissent d'un labour à plat vers le bas de la pente. Il n'y a pas lieu de distinguer
, sur ce point, entre talus à la limite des parcelles et talus intra-parcellaires. Ce sont aussi des rideaux, et non des talus de terrasses. (PmB).

Small-scale experimental simulation of talus evolution

Small-scale experimental simulation of talus evolution
In order to investigate the single particle versus collective granular effects on a talus slope and to explore the role of self-organization, the AA. studied the spatial development and temporal evolution of grains on a small-scale talus reproduced
findings with observations from natural talus slopes, and suggest that similar experiments may be helpful in understanding the evolution of taluses.

Osobennosti razvitija erozionnyh processov na otkosah zemljanogo polotna avtomobil'nyh dorog Caractéristiques du développement des processus d'érosion sur les talus de la plate-forme des routes

Osobennosti razvitija erozionnyh processov na otkosah zemljanogo polotna avtomobil'nyh dorog Caractéristiques du développement des processus d'érosion sur les talus de la plate-forme des routes
Dynamique de versant ; Erosion hydrique ; Géographie physique ; Géomorphologie appliquée ; Route ; Ruissellement diffus ; Stavropol' kraj ; Talus ; URSS d'Europe ; Versant

Définition des différents types floristiques et structuraux des haies et talus de Bretagne in Les lisières forestières.

Définition des différents types floristiques et structuraux des haies et talus de Bretagne in Les lisières forestières.
Association végétale ; Bocage ; Bretagne ; Dynamique de la végétation ; Ecosystème ; France ; Géographie de l'Europe ; Haie ; Lisière forestière ; Phytosociologie ; Synécologie descriptive ; Talus ; Taxonomie ; Typologie ; Végétation

Sedimentation processes and facies on a semi-vegetated talus, Lousteau, southwestern France

Sedimentation processes and facies on a semi-vegetated talus, Lousteau, southwestern France
A two-year survey of clast displacements on a small rockfall talus at Lousteau, southwestern France, shows that creep reaches up to 19cm/month near the talus apex, whereas the distal segment remains stable. Movements are not distributed
homogeneously but concentrate in distinct areas because of the deflection of clasts by vegetation patches. This paper presents data on slope dynamics and facies observed in this talus, and a new sedimentary model that might explain the genesis of certain types

Conservation of soil moisture by different stone covers on alpine talus slopes (Lassen, California)

Conservation of soil moisture by different stone covers on alpine talus slopes (Lassen, California)
This study reports on the influence of stone covers with different clast sizes on the soil moisture of alpine talus slopes in Lassen. Fifteen four-plot sets were sampled in the dry season (July 1990) in sandy areas and in talus covered with pebbles
the moisture conditions found in bare talus and under stone covers; and monitor evaporation losses from these experimental plots for an extended time period.

Scarp retreat rates in semiarid environments from talus flatirons (Ebro Basin, NE Spain)

Scarp retreat rates in semiarid environments from talus flatirons (Ebro Basin, NE Spain)
Triangular slope facets or talus flatirons are presented as a useful tool for the calculation of scarp retreat rates in arid regions. In the central sector of the Ebro Basin, sequences of talus flatirons have been developed around mesas capped
by Miocene limestone. These talus flatirons are grouped in 4 stages of slope evolution. The scarp retreat rate is related to the lithological and structural features of both the caprock and the underlying clay sediments and to the paleoclimatic evolution

Talus relicts in deserts: a key to major climatic fluctuations in Research contributions to the physical geography of Israel. Studies in fluvial and coastal geomorphology of arid and mediterranean regions.

Talus relicts in deserts: a key to major climatic fluctuations in Research contributions to the physical geography of Israel. Studies in fluvial and coastal geomorphology of arid and mediterranean regions.
Two modes of escarpment retreat, determined by prevailing climate, are characteristic of arid regions: (1) Under mildly arid to semiarid conditions, continuous talus aprons are formed, maintained and recede due to debris flow and wash. (2) Under
arid to extremely arid conditions, erosion, wash and gullying predominate| talus stripping is relatively fast. Sequences of flatiron like talus relicts found in hot deserts under various lithostructural conditions may reflect major climatic changes

Neue Beobachtungen an unterkühlten Schutthalden

Nouvelles observations sur l'hypothermie des talus d'éboulis
Autriche ; Cycle gel-dégel ; Glace ; Glace du sol ; Mesure ; Périglaciaire ; Talus d'éboulis ; Température ; Tirol ; Versant
L'A. présente ici les résultats de nouvelles observations (Ötztal, Tyrol) sur les phénomènes d'hypothermie sur les talus d'éboulis ainsi qu'une série de mesures de la température. Il étaye ainsi la théorie qu'il avait formulée en 1996 sur le

Fractal techniques and the surface roughness of talus slopes

Fractal techniques and the surface roughness of talus slopes
Although this paper is concerned with talus slopes, its main objectives are methodological. First, it demonstrates that the log-log plot of number of steps against steplength is an insensitive means of detecting departures from self-similarity

Considerations on the chronological and causal relationships between talus flatirons and palaeoclimatic changes in central and northeastern Spain

Considerations on the chronological and causal relationships between talus flatirons and palaeoclimatic changes in central and northeastern Spain
This paper examines talus flatiron sequences, mainly in relation to the global morphogenetic influence of Upper Pleistocene-Holocene cold events. These triangular slope facets in central and northern Spain are the only dated ones known to the AA.

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