Publication Date:
2021-06-03
Description:
This paper illustrates a geographic information system (GIS) supported methodology for the assessment
of landslide susceptibility. The methodology involves four operational steps:
survey, site analysis, macro-
area analysis
and
susceptibility analysis
. The
Survey
includes the production (or acquisition) of a large-scale
litho-technical map, a large-scale geomorphological map, a detailed inventory of past and present land-
slide events, and a high resolution DTM (Digital Terrain Model.
Site analysis
leads to the definition of
discriminating parameters
(commonly, lithological and morphometric conditions necessary but not suffi-
cient to trigger a landslide of a given type) and
predisposing factors
(conditions that worsen slope stability
but are not sufficient to trigger a landslide of a given type in the absence of
discriminating parameters
). The
different
predisposing factors
are subdivided into classes, whose intervals are established by descriptive,
statistical analysis of landslide inventory data. A numerical index, based on the frequency of landslide
occurrence, quantifies the contribution of each class to slope instability.
Macro-area analysis
includes the generation of
Litho-Morphometric Units
(LMU) by overlaying
discrimina-
ting parameters
, manual drawing of LMU envelopes (
macro-areas
), generation of
predisposing factor
maps
from the spatial distribution of
predisposing factors
, and heuristic weighting of
predisposing factor
indices.
Susceptibility analysis
includes the generation of
Homogeneous Territorial Units
(HTU) by overlaying
macro-
areas
and
predisposing factor maps
, and the application of a
susceptibility function
to the different HTU. The
resulting values are normalized before the generation of the
landslide susceptibility maps
. The methodo-
logy has been applied to the Fiumicino River catchment, located in the western side of Latium Apennine
(Central Italy) between 200 and 1300 m a.s.l. and developed on Late Miocene calcarenites, sandstones
with clay intercalations, and marls. The resulting
landslide susceptibility maps
will be employed in envi-
ronmental management. They also represent the preliminary step for the assessment of landslide hazard
and risk
Description:
Published
Description:
87-93
Description:
5.5. TTC - Sistema Informativo Territoriale
Description:
JCR Journal
Description:
restricted
Keywords:
Landslide; Geomorphology
;
GIS Methodology
;
04. Solid Earth::04.04. Geology::04.04.03. Geomorphology
;
05. General::05.01. Computational geophysics::05.01.05. Algorithms and implementation
;
05. General::05.06. Methods::05.06.99. General or miscellaneous
;
05. General::05.08. Risk::05.08.02. Hydrogeological risk
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
article
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