Physically based dynamic run-out modelling for quantitative debris flow risk assessment: a case study in Tresenda,northern Italy   总被引：1，自引：1，他引：0  

Byron Quan Luna  Jan Blahut  Corrado Camera  Cees van Westen  Tiziana Apuani  Victor Jetten  Simone Sterlacchini 《Environmental Earth Sciences》2014,72(3):645-661

Quantitative landslide risk assessment requires information about the temporal, spatial and intensity probability of hazardous processes both regarding their initiation as well as their run-out. This is followed by an estimation of the physical consequences inflicted by the hazard, preferentially quantified in monetary values. For that purpose, deterministic hazard modelling has to be coupled with information about the value of the elements at risk and their vulnerability. Dynamic run-out models for debris flows are able to determine physical outputs (extension, depths, velocities, impact pressures) and to determine the zones where the elements at risk can suffer an impact. These results can then be applied for vulnerability and risk calculations. Debris flow risk has been assessed in the area of Tresenda in the Valtellina Valley (Lombardy Region, northern Italy). Three quantitative hazard scenarios for different return periods were prepared using available rainfall and geotechnical data. The numerical model FLO-2D was applied for the simulation of the debris flow propagation. The modelled hazard scenarios were consequently overlaid with the elements at risk, represented as building footprints. The expected physical damage to the buildings was estimated using vulnerability functions based on flow depth and impact pressure. A qualitative correlation between physical vulnerability and human losses was also proposed. To assess the uncertainties inherent in the analysis, six risk curves were obtained based on the maximum, average and minimum values and direct economic losses to the buildings were estimated, in the range of 0.25–7.7 million €, depending on the hazard scenario and vulnerability curve used.  相似文献   

Fluid–rock interactions associated with regional tectonics and basin evolution     

Simone Fontana  Fadi Henri Nader  Sadoon Morad  Andrea Ceriani  Ihsan Shakir Al‐Aasm  Jean‐Marc Daniel  Jean‐Marie Mengus 《Sedimentology》2014,61(3):660-690

An integrated approach consisting of fracture analysis, petrography, carbon, oxygen and strontium‐isotope analyses, as well as fluid‐inclusion micro‐thermometry, led to a better understanding of the evolution of fluid–rock interactions and diagenesis of the Upper Permian to Upper Triassic carbonates of the United Arab Emirates. The deposited carbonates were first marked by extensive early dolomitization. During progressive burial, the carbonates were affected by dolomite recrystallization as well as precipitation of vug and fracture‐filling dolomite, quartz and calcite cements. After considerable burial during the Middle Cretaceous, sub‐vertical north–south oriented fractures (F1) were cemented by dolomite derived from mesosaline to hypersaline fluids. Upon the Late Cretaceous maximum burial and ophiolite obduction, sub‐vertical east–west fractures (F2) were cemented by dolomite (Dc2) and saddle dolomite (Ds) derived from hot, highly saline fluids. Then, minor quartz cement has precipitated in fractures from hydrothermal brines. Fluid‐inclusion analyses of the various diagenetic phases imply the involvement of increasingly hot (200°C) saline brines (20 to 23% NaCl eq.). Through one‐dimensional burial history numerical modelling, the maximum temperatures reached by the studied rocks are estimated to be in the range of 160 to 200°C. Tectonically‐driven flux of hot fluids and associated diagenetic products are interpreted to have initiated during the Late Cretaceous maximum burial and lasted until the Oligocene–Miocene compressional tectonics and related uplift. The circulation of such hydrothermal brines led to partial dissolution of dolomites (Dc2 and Ds) and to precipitation of hydrothermal calcite C1 in new (mainly oriented north–south; F3) and pre‐existing, reactivated fractures. The integration of the obtained data confirms that the diagenetic evolution was controlled primarily by the interplay of the burial thermal evolution of the basin and the regional tectonic history. Hence, this contribution highlights the impacts of regional tectonics and basin history on diagenetic processes, which may subsequently affect reservoir properties.  相似文献   

Detection of detached forced-regressive nearshore wedges: a case study from the central-southern Siena Basin (Northern Apennines, Italy)     

Ivan Martini  Simone Arragoni  Mauro Aldinucci  Luca Maria Foresi  Anna Maria Bambini  Fabio Sandrelli 《International Journal of Earth Sciences》2013,102(5):1467-1489

The detection of detached nearshore wedges formed in response to relative sea-level drops is considered one of the hottest topics in sequence stratigraphic analysis due to their importance as reservoir analogues. In fact, they usually constitute sandy and porous bodies generally encased in impermeable clay, thus presenting a good potential as traps for fluids. This paper focuses on the sequence stratigraphic analysis of the Pliocene deposits cropping out in the central-southern sector of the Siena Basin (Tuscany, Italy), a post-collisional basin of the Northern Apennines. The exposed sedimentary succession was investigated through a detailed sedimentological and stratigraphic approach, integrated by biostratigraphic analyses, aimed at a better characterization of the infilling history of this sector of the basin. Specifically, this study revealed the occurrence of repeated facies shifts that allowed the identification of two depositional sequences. In detail, a thick sand-rich body far from the basin margins, and previously considered as a turbiditic lobe, has been reinterpreted as formed in a nearshore setting during a fall in relative sea level. This body is totally encased in offshore clay, and due to the lack of physical connection with the related HST deposits, it has to be considered as a detached forced-regressive wedge. The present work led to the recognition of some sedimentological and stratigraphic features typical of falling stage systems tract deposits (e.g. presence of intrabasinal recycled materials, sedimentological evidence of a pre-existing fluvial network subsequently eroded) that can provide useful clues for the identification of detached forced-regressive nearshore wedges in core studies and poorly exposed settings.  相似文献   

Vestan lithologies mapped by the visual and infrared spectrometer on Dawn     

Eleonora Ammannito  M. Cristina De Sanctis  Fabrizio Capaccioni  M. Teresa Capria  F. Carraro  Jean‐Philippe Combe  Sergio Fonte  Alessandro Frigeri  Steven P. Joy  Andrea Longobardo  Gianfranco Magni  Simone Marchi  Thomas B. McCord  Lucy A. McFadden  Harry Y. McSween  Ernesto Palomba  Carle M. Pieters  Carol A. Polanskey  Carol A. Raymond  Jessica M. Sunshine  Federico Tosi  Francesca Zambon  Christopher T. Russell 《Meteoritics & planetary science》2013,48(11):2185-2198

We present global lithological maps of the Vestan surface based on Dawn mission's Visible InfraRed (VIR) Spectrometer acquisitions with a spatial sampling of 200 m. The maps confirm the results obtained with the data set acquired by VIR with a spatial sampling of 700 m, that the reflectance spectra of Vesta's surface are dominated by pyroxene absorptions that can be interpreted within the context of the distribution of howardites, eucrites, and diogenites (HEDs). The maps also partially agree with the ground and Hubble Space Telescope observations: they confirm the background surface being an assemblage of howardite or polymict eucrite, as well as the location of a diogenitic‐rich spot; however, there is no evidence of extended olivine‐rich regions in the equatorial latitudes. Diogenite is revealed on the Rheasilvia basin floor, indicating that material of the lower crust/mantle was exposed. VIR also detected diogenites along the scarp of Matronalia Rupes, and the rims of Severina and a nearby, unnamed crater, and as ejecta of Antonia crater. The diogenite distribution is fully consistent with petrological constraints; although the mapped distribution does not provide unambiguous constraints, it favors the hypothesis of a magma ocean.  相似文献   

Climate change and uncertainty assessment over a hydroclimatic transect of Michigan   总被引：1，自引：1，他引：0  

Jongho Kim  Valeriy Y. Ivanov  Simone Fatichi 《Stochastic Environmental Research and Risk Assessment (SERRA)》2016,30(3):923-944

Predictions of a warmer climate over the Great Lakes region due to global change generally agree on the magnitude of temperature changes, but precipitation projections exhibit dependence on which General Circulation Models and emission scenarios are chosen. To minimize model- and scenario-specific biases, we combined information provided by the 3rd phase of the Coupled Model Intercomparison Project database. Specifically, the results of 12 GCMs for three emission scenarios B1, A1B, and A2 were analyzed for mid- (2046–2065) and end-century (2081–2100) intervals, for six locations of a hydroclimatic transect of Michigan. As a result of Bayesian Weighted Averaging, total annual precipitation averaged over all locations and the three emission scenarios increases by 7 % (mid-)–10 % (end-century), as compared to the control period (1961–1990). The projected changes across seasons are non-uniform and precipitation decreases by 3 % (mid-)–5 % (end-) for the months of August and September are likely. Further, average temperature is very likely to increase by 2.02–2.85 °C by the mid-century and 2.58–4.73 °C by the end-century. Three types of non-additive uncertainty sources due to climate models, anthropogenic forcings, and climate internal variability are addressed. When compared to the emission uncertainty, the relative magnitudes of the uncertainty types for climate model ensemble and internal variability are 149 and 225 % for mean monthly precipitation, and they are respectively 127 and 123 % for mean monthly temperature. A decreasing trend of the frost days and an increasing trend of the growing season length are identified. Also, a significant increase in the magnitude and frequency of heavy rainfall events is projected, with relatively more pronounced changes for heavy hourly rainfall as compared to daily events. Quantifying the inherent natural uncertainty and projecting hourly-based extremes, the study results deliver useful information for water resource stakeholders interested in impacts of climate change on hydro-morphological processes.  相似文献   

The importance of satellite quenching for the build-up of the red sequence of present-day galaxies     

Frank C. van den Bosch  Daniel Aquino  Xiaohu Yang  H. J. Mo  Anna Pasquali  Daniel H. McIntosh  Simone M. Weinmann  Xi Kang 《Monthly notices of the Royal Astronomical Society》2008,387(1):79-91

  相似文献   

Mediterranean warming is especially due to summer season   总被引：2，自引：2，他引：0  

Giorgio Bartolini  Valentina di Stefano  Giampiero Maracchi  Simone Orlandini 《Theoretical and Applied Climatology》2012,107(1-2):279-295

We created a new homogenized daily minimum and maximum temperature data set (1955–2007) for the central Mediterranean area of Tuscany (Italy). Yearly and seasonal long-term trends of some climatic and extreme climatic indices were investigated. The results highlighted a positive trend for mean temperature of about 0.9°C per 50 years with a slightly more pronounced increase in maximum temperature. Seasonal analysis revealed a by far much greater increase in summer (June, July, August) and spring (March, April, May) temperature in respect of autumn and winter, this finding consistent with most recent Mediterranean evidences. Warm extremes showed an overall tendency to increase, while a slight not significant decrease trend was found in regard to frost days and cold extremes. Comparisons with different patterns of Mediterranean warming confirmed the magnitude of recent very fast rise in temperature, especially during summer. This change could be due to last decades modifications of general circulation patterns and land–temperature, land–precipitation positive feedback processes dependent from soil moisture. All these results confirm that the Mediterranean is a region especially responsive and thus very vulnerable to climate change.  相似文献   

Application of Advanced Analytics and Visualization in Mineral Systems     

MORRISON M. Shaunn  PRABHU Anirudh  ELEISH Ahme  PAN Feifei  ZHONG Hao  HUANG Fang  FOX Peter  MA Xiaogang  RALPH Jolyon  GOLDEN J. Joshu  DOWNS T. Robert  LIU Chao  RUNYON E. Simone  HAZEN M. Robert 《《地质学报》英文版》2019,93(Z1):55-55

正The key to answering many compelling and complex questions in Earth,planetary,and life science lies in breaking down the barriers between scientific fields and harnessing the integrated,multi-disciplinary power of Earth,planetary,and bioscience data resources.We have a unique opportunity to integrate large and rapidly expanding"big data"resources,to enlist powerful analytical and visualization methods,and to answer multi-disciplinary questions that cannot be addressed by one field alone.  相似文献   

Bank erosion in agricultural drainage networks: new challenges from structure‐from‐motion photogrammetry for post‐event analysis          下载免费PDF全文

Massimo Prosdocimi  Simone Calligaro  Giulia Sofia  Giancarlo Dalla Fontana  Paolo Tarolli 《地球表面变化过程与地形》2015,40(14):1891-1906

Drainage channels are an integral part of agricultural landscapes, and their impact on catchment hydrology is strongly recognized. In cultivated and urbanized floodplains, channels have always played a key role in flood protection, land reclamation, and irrigation. Bank erosion is a critical issue in channels. Neglecting this process, especially during flood events, can result in underestimation of the risk in flood‐prone areas. The main aim of this work is to consider a low‐cost methodology for the analysis of bank erosion in agricultural drainage networks, and in particular for the estimation of the volumes of eroded and deposited material. A case study located in the Veneto floodplain was selected. The research is based on high‐resolution topographic data obtained by an emerging low‐cost photogrammetric method (structure‐from‐motion or SfM), and results are compared to terrestrial laser scanning (TLS) data. For the SfM analysis, extensive photosets were obtained using two standalone reflex digital cameras and an iPhone5® built‐in camera. Three digital elevation models (DEMs) were extracted at the resolution of 0.1 m using SfM and were compared with the ones derived by TLS. Using the different DEMs, the eroded areas were then identified using a feature extraction technique based on the topographic parameter Roughness Index (RI). DEMs derived from SfM were effective for both detecting erosion areas and estimating quantitatively the deposition and erosion volumes. Our results underlined how smartphones with high‐resolution built‐in cameras can be competitive instruments for obtaining suitable data for topography analysis and Earth surface monitoring. This methodology could be potentially very useful for farmers and/or technicians for post‐event field surveys to support flood risk management. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

Local Holocene environmental indicators in Upper Mesopotamia: Pedogenic carbonate record vs. archaeobotanical data and archaeoclimatological models     

Simone Riehl  Konstantin E. Pustovoytov  Sara Hotchkiss  Reid A. Bryson   《Quaternary International》2009,209(1-2):154

It has been suggested that pedogenic carbonate coatings on stones in archaeological sites can be used to reconstruct late Quaternary environmental changes in the area of the Fertile Crescent. This research compares a pedogenic carbonate record from southeastern Turkey with three other local or regional sources of palaeoenvironmental information in order to evaluate the correlation of this new proxy with other independent data from the area: (1) ancient plant macroremains from archaeological sites as ecological indicators, (2) stable carbon isotope composition of ancient plant macroremains available in the literature and from our own investigations in six mid-Holocene archaeological sites, and (3) modelled Holocene precipitation and temperature changes in the northern Fertile Crescent. Comparison involved selected palynological and isotopic data from lacustrine sediments as well as speleothem isotopic records in Near Eastern locations available in the literature. Although the data show a certain amount of variation of proxy records on the regional scale, for the northern Fertile Crescent (Upper Mesopotamia) they suggest three pronounced features of the Holocene environmental history: (1) a trend toward warmer temperatures may have affected the area during the early Holocene (between ca. 10,000–6000 cal BP), (2) increased moisture availability and relatively high temperatures in the mid-Holocene (ca. between 5000 and 4000 cal BP), and (3) a significant decrease in moisture availability around 4000 cal BP.Further research is needed to enhance the chronological resolution of both pedogenic carbonate and plant macrofossil records. This study stresses the complexity of the Holocene palaeogeography of the Near East and underlines the need for careful analysis of local sources of palaeonvironmental information in the region.  相似文献