排序方式: 共有17条查询结果,搜索用时 15 毫秒
1.
Rockfalls are common in the steep and vertical slopes of the Campania carbonate massifs and ridges, and frequently represent
the main threat to the anthropogenic environment, potentially damaging urban areas, scattered houses, roads, etc. Despite
the generally limited volumes involved, the high velocity of movement (from few to tens of metres per second) poses rockfalls
among the most dangerous natural hazards to man. Evaluating the rockfall hazard is not an easy task, due to the high number
of involved factors, and particularly to the difficulty in determining the properties of the rock mass. In this paper, we
illustrate the assessment of the rockfall hazard along a small area of the Sorrento Peninsula (Campania region, southern Italy).
Choice of the site was determined by the presence of a road heavily frequented by vehicles. In the area, we have carried out
detailed field surveys and software simulations that allow generating simple rockfall hazard maps. Over twenty measurement
stations for geo-mechanical characterization of the rock mass have been distributed along a 400-m-long slope of Mount Vico
Alvano. Following the internationally established standards for the acquisition of rock mass parameters, the main kinematics
have been recognized, and the discontinuity families leading to the different failures identified. After carrying out field
experiments by artificially releasing a number of unstable blocks on the rock cliff, the rockfall trajectories along the slope
were modelled using 2-D and 3-D programs for rockfall analysis. The results were exploited to evaluate the rockfall hazard
along the threatened element at risk. 相似文献
2.
Andreas Günther Paola Reichenbach Jean-Philippe Malet Miet Van Den Eeckhaut Javier Hervás Claire Dashwood Fausto Guzzetti 《Landslides》2013,10(5):529-546
In the framework of the European Soil Thematic Strategy and the associated proposal of a Framework Directive on the protection and sustainable use of soil, landslides were recognised as a soil threat requiring specific strategies for priority area identification, spatial hazard assessment and management. This contribution outlines the general specifications for nested, Tier-based geographical landslide zonings at small spatial scales to identify priority areas susceptible to landslides (Tier 1) and to perform quantitative susceptibility evaluations within these (Tier 2). A heuristic, synoptic-scale Tier 1 assessment exploiting a reduced set of geoenvironmental factors derived from common pan-European data sources is proposed for the European Union and adjacent countries. Evaluation of the susceptibility estimate with national-level landslide inventory data suggests that a zonation of Europe according to, e.g. morphology and climate, and performing separate susceptibility assessments per zone could give more reliable results. To improve the Tier 1 assessment, a geomorphological terrain zoning and landslide typology differentiation are then applied for France. A multivariate landslide susceptibility assessment using additional information on landslide conditioning and triggering factors, together with a historical catalogue of landslides, is proposed for Tier 2 analysis. An approach is tested for priority areas in Italy using small administrative mapping units, allowing for relating socioeconomic census data with landslide susceptibility, which is mandatory for decision making regarding the adoption of landslide prevention and mitigation measures. The paper concludes with recommendations on further work to harmonise European landslide susceptibility assessments in the context of the European Soil Thematic Strategy. 相似文献
3.
A. Carrara M. Cardinali R. Detti F. Guzzetti V. Pasqui P. Reichenbach 《地球表面变化过程与地形》1991,16(5):427-445
Geographical Information Systems (GIS) and numerical cartography may greatly facilitate the development and use of statistical models for the assessment of regional landslide hazard. From a small drainage basin located in Central Italy, relevant geological and geomorphological factors were collected and processed by applying GIS technology. In particular, modules were used which both generate high-fidelity digital terrain models and automatically partition the terrain into main slope-units. The resulting information was then analysed by discriminant analysis which enabled landslide hazard and risk to be evaluated in each slope-unit. Although not lacking drawbacks, the method proved to be a feasible and cost-effective approach to landslide susceptibility assessment and mapping. 相似文献
4.
Fezer Fritz Prof. Dr. Reichenbach Bernhard Witschel Christian MA Hell Günter Prof. Dr.-Ing. Duster Manfred Dipl.-Ing Heidrich Brigitte 《GeoJournal》1987,14(4):467-478
Airphotos have been used for topographic survey since the Twenties. The “European Space Agency” (ESA), the “Deutsche Forschungs-
und Versuchsanstalt für Luft- und Raumfahrt” (DFVLR) and “Carl Zeiss” have modified this successful technique for spacecraft
and recently have tested the system over four continents. Each of these satellite photos covers a region of 189×189 km to
the scale of 1∶800000 and may be enlarged to 1∶250000 or 1∶100000. Between the altitudes of 200 and 300 km, mapmaking or-revision
seems to be economic in zones or in countries, where existing maps are of minor quality or outdated. In this paper, examples
from deserts and semideserts in the Sudan are presented. 相似文献
5.
Rock fall hazard along the railway corridor to Jerusalem,Israel, in the Soreq and Refaim valleys 总被引:1,自引:1,他引:0
We evaluate rock fall hazard along the railway corridor to Jerusalem, Israel, in the Soreq and Refaim valleys. For the purpose,
we use a combination of historical information on past rock fall events, field surveys aided by the interpretation of aerial
photographs, and numerical rock fall modeling. Historical information indicates that on July 11, 1927 an m
L
6.2 Dead-Sea transform earthquake caused rock falls in the studied area. The seismically induced rock falls damaged the railway
tracks. Field observations revealed that the source area for the 1927 failures was located in the Aminadav formation, at the
contact with the Moza formation. At the stratigraphic contact, rock blocks 100–101 m3 in size are formed as a result of tensile stresses and associated fracturing in the dolomite of the Aminadav formation, combined
with continuous creep of the blocks on the marl of the underlying Moza formation. We use topographical, geological, and geomorphological
information to calibrate a three-dimensional numerical simulation of rock falls in the studied area. We use the results of
the numerical modeling, and additional independent information, to assess rock fall hazard and the associated risk in the
Soreq and Refaim valleys. Results indicate that in the studied area, rock fall risk to the railway line to Jerusalem is due
primarily to Dead-Sea transform earthquakes, with m
L
> 6. We identify nine sections of the railway line where rock fall risk exists, for a total length of 2.5 km. We further
note that seismically induced rock falls can produce damage to the road network in the studied area, make it difficult or
impossible for earthquake casualties to reach hospitals in Jerusalem. We conclude offering recommendations on how to mitigate
the risk posed by earthquake-induced rock falls in the studied area. 相似文献
6.
Roberto Sarro Rosa María Mateos Inmaculada García-Moreno Gerardo Herrera Paola Reichenbach Luís Laín Carlos Paredes 《Landslides》2014,11(3):493-503
The Son Poc rockfall took place on the 6th of March 2013 in the municipality of Bunyola, on the southern side of the Tramuntana Range (Mallorca) and after a rainy and cold period on the region. A volume of rock of 4.000 m3 was detached from the cliff crowning the peak falling down by toppling. The impact of the boulder caused its fragmentation, and numerous boulders bounced and rolled downslope with volumes from 1 to 35 m3, following two trajectories: southwest (SW) and southeast (SE). The SE trajectory, with a larger runout (376 m), reached an urban area, where some of the boulders hit the roofs and walls of nearby houses, stopping others in their gardening areas. Fortunately, no fatalities occurred despite of the presence of some people at that moment, but the event caused great concern in a region which lives from and for tourism. The Son Poc rockfall has been simulated using RocPro3D software which uses GIS technology to produce 3D rockfall trajectories lines, estimated velocity and energy of falling blocks, as well as bounce heights, impacts, and stopping points. The results are in agreement with field observations and with a very good accuracy between real and modeled outcomes. 相似文献
7.
Regional hydrological thresholds for landslides and floods in the Tiber River Basin (central Italy) 总被引:11,自引:0,他引:11
The definition of landslide warning thresholds, based on the analysis of hydrological data, is proposed. In the Tiber River
Basin of central Italy historical information on landslides and floods, for the period 1918–1990, was available from a nationwide
bibliographical and archive inventory on geohydrological catastrophes. Hydrological data were obtained from mean daily discharge
records at various gauging stations within the basin. Several hundred hydrological events, broadly defined as a series of
consecutive days having mean daily discharge exceeding a predefined value, were identified. Hydrological parameters obtained
from the discharge records were used to rank the events according to their probability to trigger mass movements or inundations
and to define regional thresholds for the occurrence of landslides and floods. The proposed approach, not lacking limitations,
has conceptual and operational advantages, among which is the possibility of using historical information on geohydrological
catastrophes.
Received: 20 November 1996 · Accepted: 25 June 1997 相似文献
8.
9.
Landslide inventories and their statistical properties 总被引:1,自引:0,他引:1
Bruce D. Malamud Donald L. Turcotte Fausto Guzzetti Paola Reichenbach 《地球表面变化过程与地形》2004,29(6):687-711
Landslides are generally associated with a trigger, such as an earthquake, a rapid snowmelt or a large storm. The landslide event can include a single landslide or many thousands. The frequency–area (or volume) distribution of a landslide event quanti?es the number of landslides that occur at different sizes. We examine three well‐documented landslide events, from Italy, Guatemala and the USA, each with a different triggering mechanism, and ?nd that the landslide areas for all three are well approximated by the same three‐parameter inverse‐gamma distribution. For small landslide areas this distribution has an exponential ‘roll‐over’ and for medium and large landslide areas decays as a power‐law with exponent ‐2·40. One implication of this landslide distribution is that the mean area of landslides in the distribution is independent of the size of the event. We also introduce a landslide‐event magnitude scale mL = log(NLT), with NLT the total number of landslides associated with a trigger. If a landslide‐event inventory is incomplete (i.e. smaller landslides are not included), the partial inventory can be compared with our landslide probability distribution, and the corresponding landslide‐event magnitude inferred. This technique can be applied to inventories of historical landslides, inferring the total number of landslides that occurred over geologic time, and how many of these have been erased by erosion, vegetation, and human activity. We have also considered three rockfall‐dominated inventories, and ?nd that the frequency–size distributions differ substantially from those associated with other landslide types. We suggest that our proposed frequency–size distribution for landslides (excluding rockfalls) will be useful in quantifying the severity of landslide events and the contribution of landslides to erosion. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
10.
Landslides triggered by the 23 November 2000 rainfall event in the Imperia Province, Western Liguria, Italy 总被引:1,自引:0,他引:1
Fausto Guzzetti Mauro Cardinali Paola Reichenbach Francesco Cipolla Claudio Sebastiani Mirco Galli Paola Salvati 《Engineering Geology》2004,73(3-4):229-245
From mid-October to 22 November 2000, the western Liguria Region of Italy experienced prolonged and intense rainfall, with cumulative values exceeding 1000 mm in 45 days. The severe rainfall sequence ended on November 23 with a high-intensity storm that dumped more than 180 mm of rain in 24 h. The high-intensity event caused flooding and triggered more than 1000 soils slips and debris flows and a few large, complex landslides. Slope failures caused three fatalities and severe damage to roads, private homes, and agriculture. Large (1:13,000) and very large (1:5000) scale colour aerial photographs were taken 45 days after the event over the areas most affected by the landslides. Through the interpretation of the 334 photographs covering an area of 500 km2, we prepared a landslide inventory map that shows 1204 landslides, for a total landslide area of 1.6 km2. We identified the rainfall conditions that triggered landslides in the Armea valley using cumulative- and continuous-rainfall data, combined with detailed information on the time of landslide occurrence. Landslide activity initiated 8 to 10 h after the beginning of the storm, and the most abundant activity occurred in response to rainfall intensities of 8 to 10 mm per hour. For the Ceriana Municipality, an area where the landslides were numerous in November 2000, we also collected information about a historical event that occurred on 8–11 December 1910 and triggered abundant landslides resulting in severe economic damage. A comparison of the damage caused by the historical and the recent landslide events indicated that damage caused by the 1910 historical event was more diffused but less costly than the damage caused by the 2000 event. 相似文献