The mechanism for instability of a cliff made of soil mass due to downcutting was examined through an experiment using a new apparatus having no side walls. The cliff is made by piling an assembly of wetting aluminium rods. The following points can
be concluded: 1) shearing failure occurs just after a tension crack develops in association with increasing cliff height; 2) the critical height of a cliff increases with increasing cohesion of the cliff material; 3) the encroachment distance is always smaller
Notch formation processes and cliff instability in pumice flow deposits on the Asama Mountain slope, Japan
The present study attempts to investigate 1) the factors influencing on the notch formation processus in cliffs with different orientations and 2) the mechanism of cliff failure occurring due to notch growth.
Statistical analysis of factors influencing cliff erosion along a section of the West Wales coast, U.K.
This study attempts to provide a better understanding of the factors influencing cliff erosion along this section of coastline, particular reference being given to the role of wave action on unconsolidated cliffs of glacial drift
In the paper relations between width of shore platform, height of the coastal cliffs and its inclination are analysed. The study was based on profiles of the Slovenian coast obtained by remote sensing. Results show that the width of shore platform
decreases while the cliff height increases. The inclination of coastal cliffs reflects combination of rock resistance and transport intensity of accumulated material. The increasing of cliff inclination corresponds to increase of shore platform width. - (IKR)
Processes and rate of retreat of the clay and sandstone sea cliffs of the northern Boulonnais (France)
Clay ; Cliff ; Coastal environment ; Coastal erosion ; Erosion rate ; France ; Mass movement ; Nord-Pas-de-Calais ; Shore platform
Retreat of the clay and sandstone cliffs of the northern Boulonnais has been quantified using stereo photogrammetry. The low retreat rate of this coastal strip is far less than that encountered on chalk and clay-chalk cliffs of either side
Coastal cliff retreat rates at Beit-Yannay, Israel, in the 20th century
Aerial photography ; Cliff ; Coastal environment ; Coastal erosion ; Erosion rate ; Geodesy ; Israel ; Mediterranean area ; Photogrammetry ; Photointerpretation ; Twentieth Century
Research indicates that the aeolianite (Kurkar) cliffs along the Israeli Mediterranean coastline have continuously retreated eastward during the last few decades. The AA. compare the historic location of the cliff crest edge at Beit-Yannay
Evolution of salt-marsh cliffs in muddy and sandy systems : a qualitative comparison of british west-coast estuaries
Salt-marsh cliffs in the muddy Severn Estuary are mostly strong and tall. They are retreating in response to the erosive attack of wave and tidal currents chiefly through toppling failures and rotational slips. In the sandy Solway Firth
and Morecambe Bay systems, marsh cliffs are strong only in their upper parts, where a dense root-mat of marsh grasses binds the sediments. Here cantilever and toppling failures are the main response of the cliffs to tidal and wave erosion. The differences
between the three estuarine systems in the mechanisms of marsh-cliff erosion are partly reflected in the mode of preservation of the cliffs on the restoration of the conditions leading to renewal of marsh growth.
To study the effect of notch development on cliff collapse in Kuro-shima, Ryukyu Islands, the notch depth at which collapse occurs was calculated using stability analysis. Instability of a cliff increases with notch depth; collapse occurs
at the horizontal failure surface. Prior to collapse, these cliffs appear to have been separated from the adjacent cliffs by the development of vertical joints.
Coast erosion in Northeast Ireland :―Part II : Cliffs and shore platforms
Cliff ; Coastal environment ; Coastal erosion ; Coastal management ; Human impact ; Ireland ; Mass movement ; Natural hazards ; Shore platform
This paper summarises the erosion of the « hard » coast (cliffs and shore platforms) of northeast Ireland, between Portstewart, Co. Londonderry and Larne, Co. Antrim. Although there is abundant evidence of localised coastal changes
, it is not possible to define rates of erosion except on the glacial material at Portballintrae. Elsewhere, marine erosion is confined to occasional block falls or block dislodgement. Management requirements of the Co. Antrim cliffs are limited, but due consideration
should be given to the problems of accessibility, cliffs and rock-fall hazards.
Lawrence (Quebec, Canada). Specific examples are presented to illustrate the potential of such high-temporal-resolution monitoring systems, not only for quantifying cliff erosion but also for quantifying the influence of thermal regime on the weathering
processes of cliffs. Preliminary results indicate that mild winter temperature and direct solar radiation are significant factors controlling cliff retreat rates.
Geometrical simulation studies of coastal cliff failures in Liassic strata, South Wales, U.K.
Cliff ; Coastal dynamics ; Coastal environment ; England ; Mesozoic ; Numerical model ; Simulation ; United Kingdom ; Wales
This paper analyses a greater range of conditions, including various cliff face morphologies, undercut depths, joint patterns, overhanging torque forces and potential failure paths. The models have been developed to obtain probabilistic solutions
Nivation hollows and valleys in the fossil coast cliff Landborgen at Helsingborg, South Sweden
Cliffs ; Coastal environment ; Glaciation ; Hydrothermal ; Nivation hollow ; Paleogeography ; Periglacial features ; Quaternary ; Sweden
glaciation. Hydro-thermal water has made hollows and rill water small valleys in the cliff where the nivation processes begun. The nivation processes were caused by drifting snow from the east during the Weichselian.
The weathering rates of some sandstone cliffs, central Weald, England
Short-term (1-30 months) weathering rates were obtained for steep cliffs of Cretaceous Ardingly Sandstone in southern England, using a new photographic method. There was no correlation with grain size, porosity, or mean surface temperature. Highest
weathering rates were observed on south- and west-facing exposed cliffs. The results are discussed with reference to algal growth, climate, and wind direction.
Cliff-height and slope-angle relationships in a chronosequence of Quaternary marine terraces, San Clemente Island, California
A flight of Quaternary marine terraces provides a framework for quantitative analysis of abandoned sea cliff modification as a function of time. The relationships are weaker than for stream terraces and fault scarps in unconsolidated materials
but the method can probably be used successfully to distinguish early, middle and late Quaternary fault scarps or sea cliffs in consolidated materials.
Retreating cliffs in the humid tropics: an example from Paraiba, northeastern Brazil in Geomorphology of changing coastlines.
True marine cliffs are extremely rare or almost absent in the humid tropics, where they have been said to be replaced by coastal slopes covered by vegetation, subject to occasional landslides by essentially similar to inland slopes. On the Paraiba
coast, northeast Brazil, under a humid tropical climate, 21 % of the coastline consist of retreating marine cliffs, cut into Plio-Pleistocene sandy clays, a very favourable factor.
Changes in cliffed chalk coastlines are related to variations in the nature of the chalk itself but many cliffs show only minimal retreat of the cliff-top edge because many rock-falls and slides affect lower parts of the cliff-face. Most change
Arid area ; Cliff ; Cliff retreat ; Colorado ; Earth surface processes ; Erosion rate ; Escarpment ; Numerical model ; Rockfall ; Slope ; United States of America ; Weathering
of the intervening interfluves. In this model, retreat of a cliffband occurs when the height of the vertical cliff exceeds a threshold due to incision by channels on the plinth below. Debris derived from cliff retreat is distributed over the model plinth according
to the local topography and distance from the source. This debris then weathers in place, and importantly can act to reduce local bedrock erosion rates, protecting both the plinth and ultimately the cliff from erosion. In this paper, the AA. focus on 2 sets
of numerical model experiments : regulating the rate of rockfall to limit the cliff retreat; varying the weathering rate of the rockfall debris.
Numerical analysis of coastal cliff failure along the Pembrokeshire Coast National Park, Wales, UK
Cliff ; Coastal environment ; Coastal geomorphology ; Forecast ; Geotechnics ; Mass movement ; Model ; Numerical analysis ; United Kingdom ; Wales
The aim of this study is to develop a numerical model analysing the nature of cliff instability within the area with a view to predicting the likely failure mode at particular sites. Locations were selected covering an array of cliff morphologies