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61.
Luigina Vezzoli Valerio Acocella Ricardo Omarini Roberto Mazzuoli 《Basin Research》2012,24(6):637-663
Understanding the relationships between sedimentation, tectonics and magmatism is crucial to defining the evolution of orogens and convergent plate boundaries. Here, we consider the lithostratigraphy, clastic provenance, syndepositional deformation and volcanism of the Almagro‐El Toro basin of NW Argentina (24°30′ S, 65°50′ W), which experienced eruptive and depositional episodes between 14.3 and 6.4 Ma. Our aims were to elucidate the spatial and temporal record of the onset and style of the shortening and exhumation of the Eastern Cordillera in the frame of the Miocene evolution of the Central Andes foreland basin. The volcano‐sedimentary sequence of the Almagro‐El Toro basin consists of lower red floodplain sandstones and siltstones, medial non‐volcanogenic conglomerates with localised volcanic centres and upper volcanogenic coarse conglomerates and breccia. Coarse, gravity flow‐dominated (debris‐flow and sheet‐flow) alluvial fan systems developed proximal to the source area in the upper and medial sequence. Growing frontal and intrabasinal structures suggest that the Almagro‐El Toro portion of the foreland basin accumulated on top of the eastward‐propagating active thrust front of the Eastern Cordillera. Synorogenic deposits indicate that the shortening of the foreland deposits was occurring by 11.1 Ma, but conglomerates derived from the erosion of western sources suggest that the uplift and erosion of this portion of the Eastern Cordillera has occurred since ca.12.5 Ma. An unroofing reconstruction suggests that 6.5 km of rocks were exhumed. A tectono‐sedimentary model of an episodically evolving thick‐skinned foreland basin is proposed. In this frame, the NW‐trending, transtensive Calama–Olacapato–El Toro (COT) structures interacted with the orogen, influencing the deposition and deformation of synorogenic conglomerates, the location of volcanic centres and the differential tilt and exhumation of the foreland. 相似文献
62.
Paolo Mazzetti Stefano Nativi Valerio Angelini Marco Verlato Paolo Fiorucci 《Earth Science Informatics》2009,2(1-2):53-62
During the full cycle of the emergency management, Civil Protection operative procedures involve many actors belonging to several institutions playing different roles. In this context the sharing of information is a vital requirement to make correct and effective decisions. Therefore a European-wide technological infrastructure providing a distributed and coordinated access to different kinds of resources (data, information, services, expertise, etc.) could enhance existing Civil Protection applications and even enable new ones. In the recent years Grid technologies have reached a mature state providing a platform for secure and coordinated resource sharing between the participants in the so-called Virtual Organizations. Moreover the Earth and Space Sciences Informatics provide the conceptual tools for modelling the geospatial information shared in Civil Protection applications during its entire life cycle. Therefore a European Civil Protection e-infrastructure could be based on a Grid platform enhanced with Earth Sciences specific services. However Civil Protection applications stress the requirements of Earth Sciences research applications, for example in terms of real-time support. Therefore a set of high-level services specifically tailored for such applications must be built on top of the Grid platform. As a result of a requirement analysis, the FP6 project CYCLOPS has proposed an architectural framework for the future European Civil Protection e-Infrastructure. In this architecture a layer of high-level services tailored to Civil Protection applications is built on top of the EGEE Grid middleware. This architectural approach has been tested implementing a prototype of a grid-enabled RISICO, the application for wild fire risk assessment used by the Italian Civil Protection. 相似文献
63.
Valerio Lucarini Sandro Calmanti Alessandro Dell’Aquila Paolo M. Ruti Antonio Speranza 《Climate Dynamics》2007,28(7-8):829-848
We compare, for the overlapping time frame 1962–2000, the estimate of the northern hemisphere mid-latitude winter atmospheric
variability within the available 20th century simulations of 19 global climate models included in the Intergovernmental Panel
on Climate Change—4th Assessment Report with the NCEP-NCAR and ECMWF reanalyses. We compute the Hayashi spectra of the 500 hPa
geopotential height fields and introduce an ad hoc integral measure of the variability observed in the Northern Hemisphere
on different spectral sub-domains. The total wave variability is taken as a global scalar metric describing the overall performance
of each model, while the total variability pertaining to the eastward propagating baroclinic waves and to the planetary waves
are taken as scalar metrics describing the performance of each model phenomenologically in connection with the corresponding
specific physical process. Only two very high-resolution global climate models have a good agreement with reanalyses for both
the global and the process-oriented metrics. Large biases, in several cases larger than 20%, are found in all the considered
metrics between the wave climatologies of most IPCC models and the reanalyses, while the span of the climatologies of the
various models is, in all cases, around 50%. In particular, the travelling baroclinic waves are typically overestimated by
the climate models, while the planetary waves are usually underestimated, in agreement with what found is past analyses performed
on global weather forecasting models. When comparing the results of similar models, it is apparent that in some cases the
vertical resolution of the model atmosphere, the adopted ocean model, and the advection schemes seem to be critical in the
bulk of the atmospheric variability. The models ensemble obtained by arithmetic averaging of the results of all models is
biased with respect to the reanalyses but is comparable to the best five models. Nevertheless, the models results do not cluster
around their ensemble mean. This study suggests caveats with respect to the ability of most of the presently available climate
models in representing the statistical properties of the global scale atmospheric dynamics of the present climate and, a fortiori,
in the perspective of modeling climate change. 相似文献
64.
Salvatore?PascaleEmail author Valerio?Lucarini Xue?Feng Amilcare?Porporato Shabeh ul?Hasson 《Climate Dynamics》2015,44(11-12):3281-3301
Two new indicators of rainfall seasonality based on information entropy, the relative entropy (RE) and the dimensionless seasonality index (DSI), together with the mean annual rainfall, are evaluated on a global scale for recently updated precipitation gridded datasets and for historical simulations from coupled atmosphere–ocean general circulation models. The RE provides a measure of the number of wet months and, for precipitation regimes featuring a distinct wet and dry season, it is directly related to the duration of the wet season. The DSI combines the rainfall intensity with its degree of seasonality and it is an indicator of the extent of the global monsoon region. We show that the RE and the DSI are fairly independent of the time resolution of the precipitation data, thereby allowing objective metrics for model intercomparison and ranking. Regions with different precipitation regimes are classified and characterized in terms of RE and DSI. Comparison of different land observational datasets reveals substantial difference in their local representation of seasonality. It is shown that two-dimensional maps of RE provide an easy way to compare rainfall seasonality from various datasets and to determine areas of interest. Models participating to the Coupled Model Intercomparison Project platform, Phase 5, consistently overestimate the RE over tropical Latin America and underestimate it in West Africa, western Mexico and East Asia. It is demonstrated that positive RE biases in a general circulation model are associated with excessively peaked monthly precipitation fractions, too large during the wet months and too small in the months preceding and following the wet season; negative biases are instead due, in most cases, to an excess of rainfall during the premonsoonal months. 相似文献
65.
Valerio Matozzo Giulio Rova Francesco Ricciardi Maria Gabriella Marin 《Marine pollution bulletin》2008,57(6-12):453
The in vivo effects of 4-nonylphenol (NP) on functional responses of haemocytes from the cockle Cerastoderma glaucum were investigated after 7 days exposure to sublethal NP concentrations (0, 0+acetone, 0.0125, 0.025, 0.05 and 0.1 mg/l NP). Haemocytes from both controls and exposed cockles were collected, and the effects of NP on total haemocyte count (THC) and volume of circulating cells, intracellular superoxide anion () levels, acid phosphatase and lysozyme-like activities in both haemocyte lysate (HL) and cell-free haemolymph (CFH) were evaluated. Exposure of cockles to 0.1 mg/l NP significantly increased THC (p < 0.05) with respect to controls. Analysis of haemocyte size frequency distribution showed that the haemocyte fraction of about 7–8 μm in diameter and 250 femtolitres in volume increased markedly in cockles exposed to the highest NP concentration tested. Apoptosis resulting in cell volume reduction in NP-exposed animals cannot be excluded. No statistically significant variation in intracellular levels was observed. Conversely, significant increases (p < 0.05) in acid phosphatase activity were observed in CFH from 0.05 and 0.1 mg/l NP-exposed animals; no significant differences in enzyme activity were recorded in HL. Lysozyme-like activity also increased significantly in CFH from cockles exposed to 0.05 mg/l NP (p < 0.05) and 0.1 mg/l NP (p < 0.001). Instead, lysozyme-like activity decreased significantly (p < 0.05) in the HL of animals exposed to 0.05 mg/l NP. Our results suggest that NP induces variations in the functional responses of haemocytes of C. glaucum, mainly by reducing cell membrane stability and promoting cell degranulation. 相似文献
66.
The results of VLBI observations of the quasar 3C273, obtained during a multi-band campaign, are presented. The changes in separation from the core of the components along the first 2 mas of the jet were measured. The jet starts wiggling well inside the first parsec from the core. We derived the period of the oscillating jet path around the principal jet-axis in the range 2–8 mas from the core. The components' angular sizes, their peak fluxes, and turnover frequencies were also derived from the VLBI observations. We have derived lower limits to the Doppler factor by comparing the observed X-ray fluxes with those predicted by the synchrotron self-Compton model. Independent estimates were obtained through the assumption of energy equipartition between particles and magnetic field. 相似文献
67.
Kai-Kai Duan Wei Jiang Yun-Feng Liang Zhao-Qiang Shen Zun-Lei Xu Yi-Zhong Fan Fabio Gargano Simone Garrappa Dong-Ya Guo Shi-Jun Lei Xiang Li Mario Nicola Mazziotta Maria Fernanda Munoz Salinas Meng Su Valerio Vagelli Qiang Yuan Chuan Yue Stephan Zimmer 《天文和天体物理学研究(英文版)》2019,(9)
Observing GeV gamma-rays is an important goal of the DArk Matter Particle Explorer(DAMPE)for indirect dark matter searching and high energy astrophysics. In this work, we present a set of accurate instrument response functions for DAMPE(DmpIRFs) including the effective area, point-spread function and energy dispersion, which are crucial for gamma-ray data analysis based on statistics from simulation data. A dedicated software named DmpST is developed to facilitate the scientific analyses of DAMPE gamma-ray data. Considering the limited number of photons and angular resolution of DAMPE, the maximum likelihood method is adopted in DmpST to better disentangle different source components. The basic mathematics and framework regarding this software are also introduced in this paper. 相似文献
68.
The Ross Sea is a crucial area to investigate pathways of ice during the Cenozoic as it records the evolution of both the East and West Antarctic Ice Sheets. This work is based on detrital apatite fission track (AFT) data extracted from the sedimentary record of well CIROS‐2, which spans the last 5 Ma. The AFT data show a large range of ages, and most of the grains fit well with two main components that fall between 24 and 42 Ma and between 43 and 70 Ma, whereas the other components are not regularly distributed through the well, thus indicating a mixture of provenance from different areas along the Transantarctic Mountains. As a whole, our work suggests glacial expansion over the McMurdo Sound during the Pliocene, and ice periodically invading and retreating in Pleistocene. 相似文献
69.
Levels and spatial distribution of polycyclic aromatic hydrocarbons (PAHs) in superficial sediment from 15 Italian marine protected areas (MPA) 总被引:5,自引:0,他引:5
Perra G Pozo K Guerranti C Lazzeri D Volpi V Corsolini S Focardi S 《Marine pollution bulletin》2011,62(4):874-877
Surface sediment from 15 Italian marine protected areas (MPA) were analysed for polycyclic aromatic hydrocarbons (PAHs). The organic carbon percentage was also determined. Total PAH concentrations (ng g−1 d.w.) ranged from 0.71 (Penisola del Sinis) to 1550 (Miramare). Individual PAH analysis showed that three and four rings PAHs were the most frequently detected isomers and accounted for 60-70% of the PAH total concentrations. PAH ratio analysis showed a prevalence of pyrolytic PAH origin at most of the MPAs with exception of Porto Cesareo and Ustica where a petrogenic origin was detected. Results for organic carbon percentages ranged from 0.3% (Capo Rizzuto) to 2% (Punta Campanella). These results are comparable to other Mediterranean marine environments. However, our results shows that some MPAs, such as Miramare, Porto Cesareo, Isola Capo Rizzuto and Punta Campanella, are subject to strong pressure from urban and industrial activities where high PAH levels were detected. 相似文献
70.
Industrial accidents triggered by earthquakes,floods and lightning: lessons learned from a database analysis 总被引:2,自引:0,他引:2
Elisabeth Krausmann Elisabetta Renni Michela Campedel Valerio Cozzani 《Natural Hazards》2011,59(1):285-300
Natural hazards and disasters can cause major accidents in chemical and process installations. These so-called Natech accidents
can result in hazardous-materials releases due to damage to process and storage units, or pipes. In order to understand the
dynamics of Natech events, accidents triggered by earthquakes, floods and lightning recorded in industrial accident databases
were analysed. This allowed the identification of the most vulnerable equipment types, their modes of failure due to natural-event
impact and the final accident scenarios. Moreover, lessons learned for future accident prevention and mitigation were derived.
The analysis showed that pipes and storage tanks are the most vulnerable equipment for earthquakes, floods and lightning,
calling for more research of equipment behaviour under natural-event loading. The damage modes and states are strongly dependent
on the characteristics of the impacting natural event. Toxic dispersion, fires and explosions were observed as a consequence
of all three types of analysed natural events. In the case of floods, two additional scenarios were identified. These are
water contamination and the formation of toxic and/or flammable vapours upon reaction of the released chemicals with the floodwaters.
The overall number of recorded Natech accidents was found to range from 2 to 5% of all reported accidents in the analysed
databases. 相似文献