ABSTRACTS / RESUMES - Comitato Glaciologico Italiano

REMO TERRANOVA
The great landslide of Mount Ciapa Liscia in the
Aveto Valley (Ligurian-Emilian Apennines)
Dipartimento di Scienze della Terra, Universita di Genova,
corso Europa 26, 16132 Genova, Italy
The great landslide of Mt. Ciapa Liscia is situated in the
western side of Maggiorasca-Groppo Rosso mountains,
which is located on the right slope of the middle Aveto
Valley, in the Ligurian-Emilian Apennines. The geological
structure consists of five superposed tectonic units which
appear from the top to the base of the enclosed geological
section.
The landslide occupies an area of 3,378,750 rn', in which
205,625 m' at the head are formed by a large curved surface
of fault, with antiapennines direction, showing basalts
and polygenic breccias, and 3,173,125 m' are occupied by
the body of landslide. Other parameters interesting the
geometry of landslide are: maximum length of the area of
landslide =3,250 m; maximum length of the body of landslide
= 2,950; maximum width of the body of landslide =
1.400 m; difference in altitude between the top of the head
of landslide (1,658 m) and the base of the body of landslide
(715 m) = 943 m; difference in altitude between the top
of the head of landslide and the top of the body of landslide
= 300 m; supposed maximum thickness of the body of
landslide = 135 m; volume of the body of landslide =several
ten millions of m',
The Torrio village has been settled on the body of landslide
since ancient times. It is formed of a main centre at
1065 m of altitude, a minor centre at 1050 m, and some
spread houses, said Cascinelle, at the same altitude. The
secular movements of the body of landslide have caused
fractures, accidents and slope failures. Failures of the
structure of buildings were so deeply that, at the end of
XVII century, a new village Torrio was constructed
around the new church, in an area at north out of the body
of landslide, on compact and stable rocky slope, formed by
sequence of marly limestones, claystones and clayey marls
(M. Penice unit). Gradually the old village was abandoned
and today the construction of new buildings is forbidden
by low.
Some different geomorphologic units are present in the
landslide area: the upper sector of the body of landslide is
formed by an enormous pile of great blocks, often colossal,
of pillows basalts, basaltic and polygenic breccias, corresponding
to a great part of Mt, Groppe (several millions of
m'), ruined for rock falls; the medium part is formed of
boulders of basalts, arkosic and ophiolitic sandstones and
shales; the lower part down the old village Torrio is mainly
constituted of clasts of sandstones, limestones, marls, claystones,
included in a clayey and earthy matrix.
The fall of the western part of Mt. Groppe, favoured by
the great fault of Ciapa Liscia, had an important role,
among the determinant causes. The enormous volume of
rocks fallen has mobilised the lower detrital bodies, cau-
sing also translations, rotational movements and falls in the
below sedimentary units.
Today the body of landslide is active, favoured by the great
volume of water which impregnates it (probably several
millions of rn') and accelerated by the two perimetric rivers
which continuously erode it flowing together to the base of
the body of landslide. It is more and more detached from
the head of the area of landslide (Ciapa Liscia), from which
masses of altered basalts and breccias fall. Large slumpings,
debris slides are active in the medium-lower parts of
the body of landslide, showing depressions in the ground,
uphill facing slopes and several large marshy and boggy
esplanades which represent the remains of old little lakes.
A great amount of mud and detritus is removed every year
from the body of landslide and transported by the Remorano
Torrent in the lower Aveto River, causing the progressive
filling of the Boschi artificial lake.
REMO TERRANOVA 1, PIERLUIGI BRANDOLINI 2,
MARIO FEDOLINO\ GIUSEPPE CANEPA 3
& AGOSTINO RAMELLA 4
Morphological change of Genoa west coast following the
creation of a new «container» port (Liguria, Italy)
1Dipartimento di Scienze della Terra, Universita di Genova,
corso Europa 26, 16126, Genova, Italy
2 Istituto di Geografia, Universita di Genova,
via Bensa 1, 16124 Genova, Italy
3 Autorita Portuale di Genova, via della Mercanzia 2, 16123 Genova, Italy
4 Servizio Protezione civile, Comune di Genova,
p.le Ortiz, 16125 Genova, Italy
The new port area is situated along the coast between Pegli
and Voltri, wich extends rectilinearly for 5 km. It has been
built in a pre-existing morphologic and environmental
context represented by a narrow alluvial plain, wilh widths
ranging from under a hundred metres to 1 km max. and
lined by stretches of beaches, situated at the base of ophiolitic
slopes, part of the alpine chain of western-central
Liguria.
Small rills, draining little basins with area of a few km',
provide the main sediments supply of the Quaternary coastal-fluvial
plain. Alluvial covers, as has emerged from
many soundings, are mainly composed of sands, gravels,
and less frequently of silt-clay levels, with maximum thickness
rates of up to 10-20 m, on a Tertiary/ophiolitic bedrock
(gabbros, prasinites, serpentines and calc-schists}.
Since 1970, in order to satisfy new port demand, a large
embankment on the sea with a surface of approximately
700,000 rn' has been built. Today port facilities are at an
advanced stage of construction and in use as container
handling areas. This reclaimed area has been protected by
means of a southern sea dam 2,200 m long, of an eastern
breakwater 1200 m long and of a pier 600 m long for the
shelter of the western gateway of the port. It has been fil-
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