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1.
The role of the seismic trigger in the Calitri landslide (Italy): historical reconstruction and dynamic analysis 总被引：2，自引：0，他引：2
Salvatore Martino Gabriele Scarascia Mugnozza 《Soil Dynamics and Earthquake Engineering》2005,25(12):933-950
The study covered by this paper was focused on the historical case of the Calitri landslide, which was repeatedly reactivated by earthquakes, as reported since 1694. The town of Calitri (Southern Italy) is located on a ridge whose southern slope, from its top to the Ofanto river valley floor, has been historically affected by major landsliding. The last record of recurrence of the Calitri landslide leads back to the 1980 Irpinia earthquake, which caused significant damage to the town and had pervasive and visible ground effects. Based on a detailed historical reconstruction of landsliding and seismicity at Calitri, the study analysed the current static and dynamic stability of the landsliding slope by means of a finite-difference numerical analysis, taking into account the various factors of landslide initiation and kinematics. The results of the numerical analysis: (i) were consistent with the roto-translational mechanism observed upon the latest reactivation of the landslide; (ii) demonstrated that excess pore pressure redistribution caused a lag between the seismic trigger and the initiation of landsliding; and (iii) showed the impact of seismic input frequency on propagation and depth of slope instability. 相似文献
2.
Marco Petitta Gabriele Scarascia Mugnozza Maurizio Barbieri Gianluca Bianchi Fasani Carlo Esposito 《水文研究》2010,24(24):3510-3520
This study addresses the influence of landslide dams on surface water drainage and groundwater flow. In the study area of Scanno Lake and Sagittario River (Central Italy), a limestone rockslide‐avalanche formed a lake, which has an outlet that is occasionally active, showing infiltration into the rockslide dam. Several springs are present at the lake's base and are partly fed by seepage through the rockslide debris. Piezometric surveys, discharge measurements, pumping tests and chemical analyses are tools used to build a conceptual model of the groundwater flow and to evaluate the flow through the rockslide debris. Seasonal water isotopic signatures validate the assumed model, showing a mixing of infiltration recharge and groundwater seepage throughout the rockslide debris. Various recharge areas have been found for springs, pointing out those directly fed by the rockslide debris aquifer. Hypotheses about seasonal groundwater mixing between the regional carbonate aquifer and the rockslide debris aquifer are supported by isotope results. Seasonal changes in groundwater table level due to recharge and surface losses from seasonal outlet have been correlated with isotopic groundwater composition from the rockslide debris aquifer and the downstream springs; this relationship highlights the role of the rockslide dam body on the hydrodynamics of the studied area. Relationships between surface waters and groundwater in the area have been completely understood on the basis of water isotopic fingerprinting, finally obtaining a complete evaluation of groundwater renewable resources and its regimen. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
3.
4.
Reflection and refraction seismics in areas of complex geology. An example in the Northern Apennines
R. Cassinis A. Lozej I. Tabacco R. Gelati G. Biella S. Scarascia A. Mazzotti 《地学学报》1990,2(4):351-362
An experimental survey, employing refraction wide-angle reflection seismic techniques (DSS: deep seismic soundings) was carried out in the Northern Apennines (North Italy). The main objective of the experiment was the application of DSS to better-define the structure of the upper crust, down to about 15 km depth, in the crucial Alps–Apennines boundary zone. A second objective was to understand the potential of DSS as a complementary tool in areas of complex geology, where the results of near vertical reflection (NVR) are generally poor. The results of the experiment show that DSS, if properly planned, can continuously follow deep markers, and therefore impart a greater significance to faint and discontinuous NVR, as well as data on the P– wave velocity of the seismic units. 相似文献
5.
H. Laubscher G. C. Biella R. Cassinis R. Gelati A. Lozej S. Scarascia I. Tabacco 《International Journal of Earth Sciences》1992,81(2):275-289
A series of 8 new seismic refraction profiles were computed as extensions of the borehole controlled reflection profiles of the Po plain into the northern Apennines and the Ligurian Alps. They help to more clearly define the subsurface structure of this intricate ‘Ligurian knot’. In particular, it has been possible to identify a number of high velocity bodies, and they may be correlated with such geological entities as the Adriatic Mesozoic, ophiolites of the Apenninic Liguride nappes, and ophiolites or Mesozoic carbonates underlying the Antola flysch in the Alpine part of the knot. When combining the refraction and reflection lines, these bodies appear to be bounded by important dislocation surfaces, such as the Padanide sole thrust (Plio-Pleistocene), the Villalvernia Varzi line (Oligo-Miocene), the Ottone-Levanto line (Oligo-Miocene), and the Volpedo-Valle Salimbene fault (Oligo-Miocene; reactivated as a transfer fault in the Plio-Pleistocene). The 3D geometry may be interpreted in terms of regional kinematics and is compatible with a model that envisages an Oligo-Early Miocene NW translation of the Adriatic indenter, coupled with collapse in the Provençal-Ligurian sea and rotation of the Sardinia-Liguria complex into the roll-back of the Adriatic subduction zone. The refraction interpretations, extending to a depth of 15 km, are supplemented by data on the Moho configuration obtained for the European Geotraverse. The Moho appears to be dissected into a series of patches which may be interpreted in terms of the shallow crustal configuration and its history. In particular, the deepest patch appears to be terminated by the Volpedo-Valle Salimbene fault, which consequently would displace the entire crust. 相似文献
6.
Research and development of advanced technologies for landslide hazard analysis in Italy 总被引：2，自引：0，他引：2
Francesca Bozzano Paolo Mazzanti Alberto Prestininzi Gabriele Scarascia Mugnozza 《Landslides》2010,7(3):381-385
The Research Centre on Prediction, Prevention and Control of Georisks, "Sapienza Università di Roma" (CERI) was selected as
one of the World Centres of Excellence on Landslide Risk Reduction (WCoE) under the title of “Research and development of
advanced technologies for landslide hazard analysis in Italy” in the period 2008–2011. The present paper provides background
information on the activities carried out by the CERI, in the frame of the WCoE network. Pre-defined purposes have been achieved
by the implementation of integrated monitoring systems and early warning systems for landslides movements. The application
of GBInSAR technique for monitoring landslides interacting with infrastructures is discussed, and two case histories are presented.
It is shown that this technique is particularly suitable for the displacements monitoring of landslides interacting with infrastructures,
thanks to its peculiar features (i.e. areal mapping, operability under every weather and lighting conditions and continuous
and completely remote monitoring). Hence, it can be considered a very important tool for the reduction of risks connected
to the realisation and activity of large infrastructures. 相似文献
7.
F. Bozzano L. Lenti Salvatore Martino A. Paciello G. Scarascia Mugnozza 《International Journal of Earth Sciences》2011,100(4):861-879
The basin-like setting of stiff bedrock combined with pre-existing landslide masses can contribute to seismic amplifications
in a wide frequency range (0–10 Hz) and induce a self-excitation process responsible for earthquake-triggered landsliding.
Here, the self-excitation process is proposed to justify the far-field seismic trigger of the Cerda landslide (Sicily, Italy)
which was reactivated by the 6th September 2002 Palermo earthquake (M
s = 5.4), about 50 km far from the epicentre. The landslide caused damage to farm houses, roads and aqueducts, close to the
village of Cerda, and involved about 40 × 106 m3 of clay shales; the first ground cracks due to the landslide movement formed about 30 min after the main shock. A stress–strain
dynamic numerical modelling, performed by FDM code FLAC 5.0, supports the notion that the combination of local geological
setting and earthquake frequency content played a fundamental role in the landslide reactivation. Since accelerometric records
of the triggering event are not available, dynamic equivalent inputs have been used for the numerical modelling. These inputs
can be regarded as representative for the local ground shaking, having a PGA value up to 0.2 m/s2, which is the maximum expected in 475 years, according to the Italian seismic hazard maps. A 2D numerical modelling of the
seismic wave propagation in the Cerda landslide area was also performed; it pointed out amplification effects due to both
the structural setting of the stiff bedrock (at about 1 Hz) and the pre-existing landslide mass (in the range 3–6 Hz). The
frequency peaks of the resulting amplification functions (A(f)) fit well the H/V spectral ratios from ambient noise and the H/H spectral ratios to a reference station from earthquake records, obtained by in situ velocimetric measurements. Moreover,
the Fourier spectra of earthquake accelerometric records, whose source and magnitude are consistent with the triggering event,
show a main peak at about 1 Hz. This frequency value well fits the one amplified by the geological setting of the bedrock
in correspondence with the landslide area, which is constituted of marly limestones and characterised by a basin-like geometry. 相似文献
8.
S. Martino A. Minutolo A. Paciello A. Rovelli G. Scarascia Mugnozza V. Verrubbi 《Natural Hazards》2006,39(3):419-449
Results of geological, geomechanical and seismometric investigations aiming at the analysis of the seismic response in a carbonate
ridge of the Nera River valley (Central Apennines – Italy) are discussed. Geological and geomechanical surveys were aimed
at defining the stratigraphic and structural setting of the outcropping formations and the jointing conditions of the rock
mass. Velocimetric records of both ambient noise and small-magnitude earthquakes were analysed in order to identify amplification
conditions. The analysis was carried out in the time domain, through directional energy evaluation, and in the frequency domain,
through H/V spectral ratios and spectral ratios with respect to a reference station. A local amplification factor was estimated
from Housner intensity. The study revealed a significant seismic amplification in a fault zone. This effect was observed in
intensely jointed and mylonitic rock masses, located inside moderately jointed rock masses, and is the result of specific
geometries and significant impedance contrasts. A map of fault zones prone to amplification of ground motion was constructed,
taking into account the jointing conditions of the rock masses and the structural setting of the investigated ridge. The study
relied on an integrated methodological approach, which combined the available data under union and intersection criteria. 相似文献
9.
D. Casalbore F. L. Chiocci G. Scarascia Mugnozza P. Tommasi A. Sposato 《Marine Geophysical Researches》2011,32(1-2):257-271
On October 1, 2009, a small area along the Sicilian coast between the villages of Scaletta Zanclea and Giampilieri was struck by intense and concentrated rainfall causing countless small landslides widespread over the catchment area of steep subaerial creeks, locally known as Fiumara. Dense and quick debris flows were channelized within the Fiumara and destructively hit the villages and entered the sea, where they likely transformed into hyperpycnal flows. The availability of pre- and post-flood high-resolution bathymetry allows us to recognize the main features and the most significant morphological variations related to the impact of the flows on the seafloor. The passage of hyperpycnal flows on the seafloor possibly produced a suite of mass-wasting events, encompassing sheet landslides (i.e. erosive scours), retrogressive slope failure on loose sediment at the canyon headwall and rock-falls on the conglomeratic bedrock along canyon sidewall. The possible causes of these events are discussed on the basis of available morphological evidence and geotechnical considerations. Finally, the widespread occurrence of mass-wasting features (i.e. submarine landslide scars) morphologically similar to those generated by the 2009 flash flood allows us to hypothesize, from one side, a strong correlation between this catastrophic event and the evolution of submarine canyons, and from the other side, the possible use of these features for the assessment of flash-flood occurrence. 相似文献
10.
Giannini Leonardo Maria Varone Chiara Esposito Carlo Marmoni Gian Marco Scarascia Mugnozza Gabriele Schilir&#; Luca 《Landslides》2022,19(8):2005-2019
Landslides - Earthquake-induced landslides represent a significant seismic hazard since they can largely increase the damage and losses due to a seismic event, an issue that must be considered in... 相似文献