ABSTRACTS / RESUMES - Comitato Glaciologico Italiano

large non-karstic area which gives the streams disappearing
in the sinkholes. There are lots of sinkholes and springs
but we know only a few explored caves.
We have measured the size of the karstic and non-karstic
catchment areas, the water input to the sinkholes, the valleys'
cross sections and - if it is known - the passages' sizes
of the sinkhole caves. The relation between the parameters
belonging to the same catchment area was very strong so
we can estimate the unknown passages' sizes underlying
the unexplored sinkholes.
Naturally we must be careful to apply the method because
there are lots of other factors which we are unable to show
but they play very important role in the cave forms, e. g.
softer rock strata, tectonic faults, e.t.c. In the future we
would like to expand our research to the spring caves and
their catchment areas. We wanted to compare the absolute
size of the catchment area, the rate of the karstic and non
karstic catchment area with the caves' sizes.
ANTONELLA BASCIANI 1, GERARDO BRANCUCCI 2,
ANNALISA MANIGLIO CALCAGNO 1, LORENZO CAPIZZI 3,
ADRIANA GHERSI 1
& ELISABETTA RUGGIERO 4
The influence of the «Terraced Lands» on the stability
of the Ligurian slopes
1 Dipartimento Polis, Facolta di Architettura, Universita di Genova,
str. S. Agostino, Genova, Italy
2 Dipartimento Scienze della Terra, Universita di Torino,
via Valperga Caluso 35, Torino, Italy
3 Datasiel, via Merano 22, Genova, Italy
4 Istituto di Rappresentazione, Facolta di Architettura,
Universita di Genova, str. S. Agostino, Genova, Italy
Since the most ancient times, the territory of Liguria has
been concerned by a progressive and widely spread shaping.
The mainly mountainous features of the slope, even of the
steepest ones has always been inevitable. Above all, in recent
times, the industrialisation of the coast line let all the
complex and perfectly efficient system of water regulation,
drainage and farming organisation of terraced lands run
wild, causing remarkable, widespread hydrologic disarrangement
and slope unsteadiness. '
We think there is an urgent need of testing new research
methods on the territory in order to be able to focus on the
various aspects of the degradation and diffusion of this
phenomenon. On this subject, the team constituted by Regione
Liguria, Datasiel and Genoa University intends to
bring out a morphological and structural analysis of the Ligurian
terraced lands, aiming, by means of Gis technologies,
at the map-making of area in danger because of the
terraced structure decay.
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ROBERTO BASILI, CARLO BOSI & PAOLO MESSINA
Paleo-landsurfaces and tectonics in the
Upper Aterno Valley (Central Apennines)
Cnr - Centro di Studio per la Geologia Tecnica,
via Eudossiana 18, Roma, Italy
Remnant landsurfaces are a widespread and evident
morphological feature all over the central Apennines. They
are represented by low-relief erosional surfaces with a typical
step-like topography. Landurfaces unconformably cut
various rocks and formations (Meso-Cenozoic carbonate
Units, Miocene siliciclastic Units and Plio-Quaternary continental
deposits).
We hypothesize that these surfaces originated from the lateral
erosion of ancient rivers and streams; so that successions
of remnant erosionallandsurfaces can be assimilated
to fluvial terrace successions, resulting from an interaction
process involving erosion, deposition, tectonic uplift and
climatic changes.
Recognition and analysis of these surfaces and their relations
with the Plio-Quaternary continental deposits have
greatly contributed to the understanding of intermontane
basins and to their geological evolution. In this work remnant
landsurfaces are in particular used to investigate the
elevated areas between intermontane basins in order to i)
reconstruct the landscape evolution of these areas; ii) indicate
the'possible presence of zones affected by differential
vertical movements and iii) assess the geometry and kinematics
of the structural elements.
The investigated area is ca. 2000 km'. Single patches of
remnant surfaces, from a few hm' to a few km', have been
identified from aerial-photo interpretation and pin-pointed
on topographic maps (at the scale 1:25,000). In addition,
field surveys supplied data on clastic continental deposits.
Correlation between patches of remnant landsurfaces was
based on the following criteria: i) spatial continuity or quasi-continuity;
ii) accordance of elevation, taking into account
possible original gradients; iii) equivalence of position
within single local successions of remnant landsurfaces.
This procedure led to the reconstruction of about
twelve paleo-Iandsurface levels distributed between 600 m
and 1900 m a.s.l., levels being separated from one another
by slope from 50 (minimum) to 300 m (maximum) high.
On the basis of these observations we propose the following
«model» of tectonic behaviour of the elevated areas
between intermontane basins during Plio-Quaternary times.
The general landscape evolution seems to be due to
the interaction between fluvial dissection and faulting. The
studied area would belong to a single large block having
homogeneous tectonic behaviour, which was uplifted while
minor portions of it (a few ten km") were being deformed
along NW-SE trending normal faults.
In conclusion, we can say that to study remnant landsurfaces
is an useful method to reconstruct the geological evolution
of intermontane basins and of elevated areas separating
them. For these areas it would also be possible to