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31.
Domenico Giusti George E. Konidaris Vangelis Tourloukis Mattia Marini Matteo Maron Andrea Zerboni Nicholas Thompson George D. Koufos Dimitris S. Kostopoulos Katerina Harvati 《Boreas: An International Journal of Quaternary Research》2019,48(3):713-730
By applying advanced spatial statistical methods, spatial taphonomy complements the traditional taphonomic approach and enhances our understanding of biostratinomic and diagenetic processes. In this study, we elaborate on a specific aspect – spatial anisotropy – of taphonomic processes. We aim to unravel the taphonomic history of the Early Pleistocene vertebrate assemblage of Tsiotra Vryssi (Mygdonia Basin, Greece). Circular statistics are used for the fabric analysis of elongated elements; geostatistics (directional variograms), wavelet and point pattern analyses are applied for detecting anisotropy at the assemblage level. The anisotropy of magnetic susceptibility (AMS) of sedimentary magnetic minerals is also investigated. The results, integrated with preliminary remarks about the differential preservation of skeletal elements, sedimentological and micromorphological observations, suggest multiple dispersion events and recurrent spatial re‐arrangement of a lag, (peri)autochthonous assemblage, consistent with the cyclical lateral switching of a braided fluvial system. Furthermore, this study offers a contribution to the building of a spatial taphonomic referential framework for the interpretation of other fossil vertebrate assemblages, including archaeo‐palaeontological ones. 相似文献
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Mattia Fosci 《Climate Policy》2013,13(2):170-190
It is argued that the subordination of policies to results-based payments for emissions reductions causes severe economic inefficiencies, which affect the opportunity cost, transaction cost, and economic rent of the programme. Such problems can be addressed by establishing sound procedural, land, and financial governance at the national level, before Reducing Emissions from Deforestation and Forest Degradation (REDD+) economic incentives are delivered at scale. Consideration is given to each governance dimension, the entry points for policy intervention, and the impact on costs. International support must consider the financial and political cost of governance reforms, and use a pay-for-results ethos based on output and outcome indicators. This can be done in the readiness phase but only if the latter's legal force, scope, magnitude, and time horizon are adequately reconsidered. This article provides ammunition for the institutionalists’ argument that United Nations Framework Convention on Climate Change (UNFCCC) Parties must prioritize governance reforms between now and the entry into force of the new climate agreement in 2020. Finally, specific recommendations about how such governance reforms can be achieved, which will create the basis for the programme's financial sustainability, are offered. Policy relevance UNFCCC Parties could make the most cost-effective use of REDD+ resources if they were to prioritize investments in governance over the interim period 2012–2020. REDD+’s financial, technical and political capital should be used to establish sound procedural, sectoral (land), and financial governance systems in relevant countries. This will generate long-term economic savings, compared to an approach that privileges the implementation of results-based payments for emissions reductions. In particular, it will reduce economic inefficiencies, which affect the opportunity and transaction costs, and the private rents embedded in the current programme design. In order to promote the necessary policy reforms, stakeholders should work together to address technical, financial, and political economy issues at the domestic level. In particular, UNFCCC Parties should re-conceptualize the readiness phase by strengthening its legal force, expanding its scope, increasing its financial firepower, and extending its time horizon. 相似文献
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Zizi Mattia Chisari Corrado Rouhi Jafar De Matteis Gianfranco 《Bulletin of Earthquake Engineering》2022,20(2):963-996
Bulletin of Earthquake Engineering - Simulating the mechanical behavior of masonry structures with reasonable approximation using numerical models is a complex issue, mainly due to the... 相似文献
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Sartirana Davide Rotiroti Marco Bonomi Tullia De Amicis Mattia Nava Veronica Fumagalli Letizia Zanotti Chiara 《Hydrogeology Journal》2022,30(4):1157-1177
Hydrogeology Journal - The significant increase in urbanization has resulted in greater use of the subsurface in urban planning and, therefore, increased interaction between groundwater and... 相似文献
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Carlo Doglioni Eugenio Carminati Mattia Crespi Marco Cuffaro Mattia Penati Federica Riguzzi 《地学前缘(英文版)》2015,6(3):401-418
The possibility of a net rotation of the lithosphere with respect to the mantle is generally overlooked since it depends on the adopted mantle reference frames,which are arbitrary.We review the geological and geophysical signatures of plate boundaries,and show that they are markedly asymmetric worldwide.Then we compare available reference frames of plate motions relative to the mantle and discuss which is at best able to fit global tectonic data.Different assumptions about the depths of hotspot sources(below or within the asthenosphere,which decouples the lithosphere from the deep mantle) predict different rates of net rotation of the lithosphere relative to the mantle.The widely used no-net-rotation(NNR) reference frame,and low(0.2°-0.4° /Ma) net rotation rates(deep hotspots source) predict an average net rotation in which some plates move eastward relative to the mantle(e.g.,Nazca).With fast(1° /Ma) net rotation(shallow hotspots source),all plates,albeit at different velocity,move westerly along a curved trajectory,with a tectonic equator tilted about 30° relative to the geographic equator.This is consistent with the observed global tectonic asymmetries. 相似文献
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Determinations of the absolute age of cleavage formation can provide fundamental information about the evolution of orogenic belts. However, when applied to cleavages in slates and phyllites, conventional dating methods are complicated by problems related to mineral separation and the presence of multiple cleavage generations. In situ high-spatial-resolution 40 Ar/39 Ar laser microprobe geochronology and microstructural observations indicate that the age of cleavage formation in slates and phyllites can be constrained by analysing zones of tightly packed cleavage domains. Three regionally developed cleavages (S2 , S3 , and S4 ) are present in the northern Taconic Allochthon of Vermont and New York. Representative samples were studied from a variety of localities where these cleavages, which are defined by white micas, are well developed. In the suite of samples, only S3 and S4 are expressed as domains that are sufficiently wide and spatially isolated in thin section to permit quantitative 40 Ar/39 Ar geochronology. Mean 40 Ar/39 Ar laser microprobe ages for these domains are 370.7 ± 1.0 Myr for S3 and 345.5 ± 1.7 Myr for S4 . Because estimates of the Ar closure temperature for white micas are substantially higher than the inferred growth temperatures of the micas defining S3 and S4 , these values are interpreted as periods since cleavage formation. This interpretation is consistent with independent geochronological constraints on the age of the Acadian orogeny in the region. 相似文献
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Mario Mattia Mimmo Palano Valentina Bruno Flavio Cannavò Alessandro Bonaccorso Stefano Gresta 《地学学报》2008,20(5):370-377
The tectonic deformation of the Lipari–Vulcano complex, one of the most important active volcanic areas of the Mediterranean region, is studied here through the analysis of 10 years (1996–2006) of GPS data from both three permanent and 13 non‐permanent stations. This area can be considered crucial for the understanding of the interaction between the Eurasian and African plates in the Mediterranean area, and, in general, this work emphasizes a methodological approach, already applied in other areas worldwide ( J. Geophys. Res., 1996, 101 , 27 957 ; J. Geodyn., 1999, 27 , 213 ) where geodetic data and strain parameters maps of critical areas can help to improve our understanding of their geodynamical aspects. In this framework, this study is aimed at providing a kinematic deformation model on the basis of the dense geodetically estimated velocities of the Lipari–Vulcano complex. In particular, the observed deformation pattern can be described by a combination of (1) the main N–S regional compression and (2) a NNE–SSW compression with a small right‐lateral strike slip component acting along a tectonic structure trending N°40W between the two islands. This pattern was inspected through a simplified synthetic model. 相似文献
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P. P. Alberoni S. Nanni M. Crespi M. Monai 《Meteorology and Atmospheric Physics》1996,58(1-4):123-138
Summary A case study of supercell thunderstorm development over Po Valley in northern Italy is discussed. The data were collected during MATREP, a field project operated in the month of June 1990. During the late morning hours of 8 June, before the passage of a cold front, a supercell and a single cell developed at the same time in eastern part of Po Valley, about 60 km apart from each other.Surface mesoscale analysis helps to explain these different storm evolutions due to interaction among local circulations, Adriatic Sea and orography. While dry wind (foehn) dumps the thermodynamic instability in single-cell environment, a moisture circulation affects the origin area of supercell. Computation of corresponding instability indices again supports the peculiar evolution of the two storms which is also analyzed by means of radar data.With 20 Figures 相似文献
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