|
|
The
SLAM services and products have been tailored to the requirements
proposed by national and local organizations, involved in landslide
risk assessment and management in Italy and Switzerland.
Consequently,
these services and products will improve the users’ databases and
decision support systems.
In
Italy, the
Landslide
Motion Survey
has been developed for the whole extent of Arno River Basin and for
an area in Campania region.
In Switzerland, the service covers several geographic areas of
the eastern
part of Valais and Berne Cantons, Canton Ticino and Canton Fribourg.
The
Landslide
Displacement Monitoring
is developed and tested in Italy for the Arno River Basin in
the test sites of Pelago, Poggibonsi, Chianciano and Capannori municipalities and in
four test sites in Campania: San Marco dei Cavoti, Reino, Pesco
Sannita and Campolattaro sites.
Meanwhile in Switzerland the service is
developed on the following test sites: Grindelwald and Lauterbrunnen
in Canton Berne, La Frasse,
Montagnon, Gräechen and Grubengletscherin in Canton Valais, Biasca, Preonzo, Airolo
in Canton Ticino and the area around Schwarzsee in Canton Fribourg.
The
Landslide
Susceptibility Mapping
is developed in the whole Arno Basin and Grinderwald in Switzerland.
|
|
Arno
River Basin
|
|
The
hydrographical basin of Arno river, located in the central
Apennines, has an extension of about 9.000 km2.
The average slope of the basin is 0.6%, and the average
elevation is 353 m with maximum elevation of 1,600 m.
The
hill regions are predominant as the 55,3% of the whole river basin is
located at an altitude lower than 300 m a.s.l., 30,4% between 300 and
600 m a.s.l., 9,8% between 600 and 900 m a.s.l. and only the 4,5%
higher than 900 m a.s.l..
|
|
Regarding the land
use,
the basin is covered by 350,000 ha of forested area and 431,488 ha of
cultivated lands.The
geology of the area is mainly formed by impermeable rocks, such as
clays, marls, clayey schists,
marley limestones, and compacted sandstones. Only the 5% of the
whole basin extension is covered by permeable rocks. The alluvial
soils, almost not very tick, cover the 23% of the area.
As
direct effects, the area is mainly characterised by high erodibility
causing landslides and land flows trigged by lashing rains and
earthquakes. The over 3000 landslides in the territory are classified
as rotational (55%), translational (20%), rockfalls (12%), rockflow (7%),
topple(5%)
and side spreading (1%).
Many
mass movements affect urban areas, such as San Miniato, nearby
Florence, Chiusi della Verna, San Gimignano, Volterra, Chianciano
Terme and Montepulciano. Other landslides directly involve important
infrastructures, crucial for the Italian national transport network,
such as the A1 superhighway and the under-construction
high-velocity railway line. These phenomena generate very high risk
scenarios with respect to the elements at risk: 2,581,369 people
living within the basin. Moreover, this area has an high cultural
relevance.
|
|
top
|
|
|
| Chianciano
Terme (Si)
|
|
|
|
The urban area of Chianciano Terme (SI) is affected by a set of slope instability phenomena, located in Castagnolo-Le Case, in the northern part of the inhabited centre, and in Chianciano Bagni, in the southern part of the town.
Such slope instability phenomena translational slides, simplex and complex, rupture surfaces located within deposits
of sand and clay and calcareous rock.
Many damages to civil buildings have been reported in several areas of the inhabited centre and many interventions have been performed since ’70.
| 
|
|
top
|
| Pelago
(Fi)
|
|
|
|
Carbonile area is located along Arno River, close to the city of Firenze, within Pelago
Municipality.
Is is threatened by 4 landslide phenomena, but the largest landslide body is named Carbonile 2. From the 1985 the landslide body has been affected by several reactivations, which have caused many damages in the village areas, involving routes, civil buildings and few factories.
During the last years different sectors of the landslide have been stabilized through the construction of drainage systems and retaining walls, but some areas are still in
movement.
| 
|
|
top
|
| Poggibonsi
(Si)
|
|
|
|
The test area named Casalino is located within Poggibonsi Municipality.
The slopes present cuts and rift resulting from a yielding deformation which interest mainly alternation of sand and slime or gravel and slime.
The area is interested by yielding phenomena in concurrence with gravitative events due to the pressure increment and with horizontal movement due to terrain removal.
Since 1990 the landslides have been stabilized through the construction of drainage systems and retaining
walls.
|
|
|
top
|
| Capannori
(Lu)
|
|
|
|
The urban area of Capannori (Lu) is affected by a set of slope instability phenomena, located in particular in San Gennaro and Matraia sites, in the northern part of the inhabited
centre.
Many damages to civil buildings have been reported in several villages:
Petrognano, Matraia, Tofori and S.Pietro in Marcigliano
Important interventions have been funded by Regione Toscana in order to mitigate
slope instability phenomena in Capannori
municipality.
|
|
|
top
|
| Regione
Campania
|
|
|
| The average height of the analyses area is 398 m with a maximum height of 981. The territory can be classified as principally hilly, in fact the 52% of territory has got a height between 300 and 600 meters, while the 34% has got a height between 0 and 300 m and the 9% between 600 and 900 m, the 1% only has got a height beyond 900 meters, the slope acclivity is inferior to 15% for the 33% of the area. Almost the 80% of the territory is classified as cultivation area, while the 12% is covered by
forest.
| 
|
The geologic formations are constituted by impermeable rocks overall.
The lithology more abundant are clay and marls, but in some zones are present ,
as intercalation of various thickness, calcareous rock sometimes enriched in flint. The alluvional sediments,
characterized by a thin thickness, covered few km2 of land. Therefore the majority
of rock terms are susceptible to erosion, in fact , the analyzed area is rich in landslides as flow, rotational and translational slide. The first represent the more abundant typology of slope instability. The triggering mechanisms seem to be the elevated quantity of rain and his intensity and the earthquakes sometimes hit the area.
The instability phenomena are also abundant in the surrounding of numerous villages, they create risks for the population and provoke damage to public and private building, historical and cultural heritages and infrastructure as road and bridge.
top
|
| San
Marco dei Cavoti (Bn)
|
|
|
|
The slope instability phenomena involve strongly the territory surrounding San Marco dei Cavoti village.
In particular, the mass movements are located to east and west of urban center.
The triggering factors of slope instability are probably related to a close interaction between material properties and morphologic characteristics. In fact, we find high value of inclination in correspondence with geological formations rich in clay and marls and with favorable attitude of the rock layers.The typologies of landslides we can find are creep, translational and rotational slides and complex movements.
| 
|
The different typologies we can survey in little area are due to great amount of combinations between geo-lithologic characteristics and geomorphology of the territory.
As a consequence of landslides activity, a lot of buildings and roads have been damaged, unless for the areas where adequate interventions have been done in the past and in the recent years to contrast the action of the instability
phenomena.
|
|
top
|
| Pesco
Sannita (Bn)
|
|
|
|
The mass movements affect strongly Pesco Sannita village: they are widespread above all the northern side of the urban center, but they are occur also in the other parts.
The typologies of landslides surveyed are rotational and translational slide and flow. The latter constituted almost the totality of occurred phenomena. This situation outlines the main role of the geo-lithologic characteristics of the geologic formations involved in the phenomena. In fact there is abundance in plastic materials as clays and marls, particularly prone to flow, triggering instability also over slopes with low inclination.
| 
|
|
The persisting of mass movements caused damages to infrastructures as roads and building. Some interventions have been carried out in the past but they are not completely efficacious.
|
|
top
|
|
Campolattaro (Bn)
|
|
|
|
The study area is localized in the Northern part with respect to the urban center of
Campolattaro a village a few kilometers far from Benevento.
Several phenomena of slope instability interest the area under analysis. In particular, the greater of such phenomena are located along the east side of the valley where the dam
which bridles Tammaro river, tributary of Calore river.
These landslides phenomena can be attributed to an interaction between geo-lithologic factors and dam structure. The first predisposing to
slope instability due to the lithology, abundant presence of marls and clay, layer attitude and discontinuity surface between the geological formations with different geolithologic and geo-mechanic characteristics. The latter acts with cyclic internal pressure variation provoking the uninterrupted change of acting forces magnitude.
The landslides typologies are translational slides, flow and complex
movements.
|
|
|
|
|
top
|
|
Reino (Bn)
|
|
|
The phenomena of slope instability interest the whole area around the urban center of Reino. In particular, such phenomena are located along the north side and the south side of the village.
These landslides phenomena can be attributed to an interaction between geo-lithologic factors and geomorphology. The first predispose to slope instability in relation with lithology, abundant presence of marls and clay, layer attitude and discontinuity surface between the geological formations with different geolithologic and geo-mechanic characteristics. The latter occur where the slope acclivity is greater than the internal angle of friction of the materials.
|
|
|
The following typologies of landslides are recognizable: traslational and rotational slide, flow and complex movements. A lot of buildings are affected by severe wall lesions due to the persistent action of the active landslides and to a lack of effective contrasting measures.
|
|
top
|
|
Canton Valais
|
|
|
|
Canton of Valais has an extension of 5,225 km2,about the 20% of the area is
covered by agricultural land. The Canton has 160 municipalities,
278,000 inhabitants, with a density of 53 inhabitants / km2.
In high-mountain regions the mass-transport systems are the results of
steady mass shifts and catastrophic mass-movement events. The
equilibrium of these systems is markedly influenced by ice occurrence,
which makes high mountains areas especially sensitive to climate
impacts. The creeping and thawing of frozen debris, often found as
permafrost, is a significant factor for the prone of periglacial
debris flows and related slope instabilities. Not only instabilities
of debris slopes but also instabilities of rock slopes can be
connected to glacial and permafrost processes. Glacier retreats, for
instance, affect the stability of valley flanks, or varying ice
content affects the rock hydrology. The difficulty in accessing
high-mountain regions makes the use of remote-sensing techniques
preferred.
Such system interactions described above, clearly show the urgent need of
an integral hazard assessments accounting for a variety of relevant
processes in high mountains, also considering that a variety of
natural hazards in high mountain regions are affecting human
activities.
|
|
top
|
|
Grubengletscher
|
|
|
The
Grubengletscher located in Saas Balen, Saastal, Oberwallis at an
altitude between 1.700 and 3.000 a.s.l., covers an area of 12 km2.
The geology of the area is characterized by the presence of schistes and
limestones. Regarding the land use, the test site is covered by ice,
stones, lakes, forest and grass. Grubengletscher is a permafrost
region characterized by local instabilities.
The village of Saas Balen is currently the site under high risk.
|
|
|
top
|
|
Montagnon
|
|
|
This
area is located in Leytron, Unterwallis, covering an extension
of 5 km2. The test site is placed at an altitude between 500
and 1300 m a.s.l. From a geological point of view the
prevailing lithotype is the schistes (Aalénien).
Montagnon
is affected by a landslide with 50 m of thickness
fast-movement part which represents a threat for Montagnon
Village.
|
|
|
top
|
|
Graechen
|
|
|
Graechen is located in Randa, Mattertal and covers 20 km2
This site is placed at an altitude between 800 and 2700 m a.s.l. This area from a geologic point of view, is charachterized by the presence of schistes, gneiss and quartzites. Regarding the land use the study area is covered by ice, stones, forest and grass. Graechen is affected by large landslide with slow parts appr. 100 m of thickness and a permafrost block glacier in Ritigrabe-Seetalhorn
The instability phenomena represent a threat for Grachen Village involving roads and bridges.
This area is currently monitored through piezometers and thermistores positioned in several permafrost boreholes.
|
|
|
top
|
|
La
Frasse (Canton Vaud)
|
|
|
|
La
Frasse is located in Aigle-Sepey. This
area is placed at an altitude ranging between 800 and 1.900 m a.s.l.
and is characterized by limestones, flysch and Quaternary deposits.
Regarding the land use La Frasse is covered by forest, grass and roads.
The instability phenomena represent a threat for houses, roads and
transport lines inside the study area.
|
|
|
top
|
|
Berne
Canton - Grindelwald and Lauterbrunnen
|
|
|
|
Canton
of Bern has an extension of 5,959 km2,about the 43% of the
area is covered by agricultural land. The Canton has 400
municipalities, 947,000 inhabitants, with a density of
159 inhabitants / km2. In
this area, 125 known landslides has been identified. The
Grindelwald and Lauterbrunnen areas comprise deeply incised valleys,
formed by glacial and fluvial erosion. The morphology is rugged with
very steep to vertical rock cliffs and underlying steep slopes. The
altitudes range from 800 m (Lauterbrunnen) to over 4.000 m (Jungfrau)
over a distance of few kilometers. The geology includes Alpine
Helvetic Nappes and the Autochthonous cover of the Aar-Massif. The
bedrock is partially covered by glacial and alluvial deposits variable
in thickness. Slope instabilities occur within the cover as well as
within the bedrock. There exist several larger as well as a host of
smaller and mostly shallow landslides including rock instabilities in
different lithological units. Mass
movements affect more or less inhabited areas around the towns of
Grindelwald, Lauterbrunnen, Wengen and Mürren as well as parts of the
towns themselves. Hazard due to slope and rock instabilities exist
also for the main and only access roads to Grindelwald and
Lauterbrunnen and corresponding railway lines. Changes in the high
alpine Permafrost areas and instabilities due to retreating glaciers
are another issue for the high altitude railway line to Jungfraujoch
and its corresponding touristic and scientific installations.
|
|
top
|
|
Grindelwald
|
|
|
|
The
test area consists of an alpine circus around the important Swiss
ski-resort center of Grindelwald. In its southern part, the area is bordered by the high mountain chain of the
Eiger,
Mettenberg and Wetterhorn north faces. The
community of Grindelwald has a total surface of 171 km2
including the settlement of Buglauenen.
The geology comprises Helvetic
Nappes and autochthonous
sedimentary cover derived from the
Aar-Massif.
| 
|
The strata include mainly limestones with numerous intercalations of
clayey schists that are often found in a dip-slope configuration. The
quaternary cover varies considerably in thickness and composition, and
are formed mainly by young moraines of local glaciers from the last
glaciation and alluvial fan deposits.
The densely populated area of the town and community of Grindelwald is
affected by large and deep-reaching landslides as well as shallow ones.
|
|
top
|
|
Canton Ticino
- Tre
valli
|
|
|
The region of Tre Valli in northern Ticino has an approximate extension of 1’100 km2. The three local areas of Biasca, Preonzo and Airolo, where there are active
landslides, were selected for detailed monitoring.
In the community of Biasca there are two areas of risk: Monte Crenone and Biborgh in Val Pontirone.
|
|
|
In Preonzo the site under risk is a small industrial area, including the national and cantonal roads.
The historical landslide above Airolo is affecting the village with all its infrastructures, including national and cantonal roads and railway.
|
|
top
|
|
|
|
Canton Fribourg - Schwarzsee
|
|
|
Schwarzsee region is located at altitudes of 1000 – 1700 m a.s.l.
The landslide processes are represented by large landslide (20 m of thickness) with slow and fast parts.
The area under higher landlside risk are Hohberg and La Berra sites.
Hohberg is studied since 1993 with mapping.
Since 1995 a GPS-network is measured 1-3 times per year.
|
|
|
top
|
|
|
|
|
|
|
|
|
|
|
|
|
|
