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61.
Three points raised in the paper by Tedesco and Sabroux (1987) are dealt with. (1) The inconsistency between the water partial pressure calculated by Tedesco and Sabroux (1987) and saturation pressure is due to the improper use of the water-gas-shift reaction as a geothermometer. In fact Tedesco and Sabroux (1987) do not take into account the distribution of gas species between the coexisting vapour and liquid phases. (2) The depth of the steam reservoir is evaluated by Tedesco and Sabroux (1987) in too simplistic a way. This matter should be treated with greater care owing to the high social impact of any consideration on the Phlegraean Fields system. (3) The reliability of carbon monoxide determination at the concentration level encountered at Solfatara depends on the collection method rather than on the gas-chromatographic technique.  相似文献   
62.
Both the 34 value and the total S content of products from Vulture Volcano, Italy are mainly controlled by the separation of S gases, predominantly SO2, from high f O2magmas containing S predominantly as SO 2- 4 . The addition of evaporites to such magmas appears to be a relatively uncommon and limited phenomenon. The total S content of the most primitive product of Vulture Volcano (5600 mg/kg) is very high. The high 34S value of 4 indicates an origin through the partial melting of a mantle containing high S, enriched in 34S of unknown origin.  相似文献   
63.
Log–log correlation plots between the dissociation constants of known metal–chromate complexes and those of corresponding metal–sulfate complexes at 25 °C, 1 bar were used to derive the standard partial molal Gibbs free energies of formation of unknown metal–chromate complexes involving either (i) monovalent cations, divalent cations, and trivalent lanthanides or (ii) trivalent cations (excluding those of rare earth elements, REE) and tetravalent cations. For each of these two classes of ionic associations, empirical relationships between the standard partial molal volumes, isobaric heat capacities and entropies of known metal–chromate complexes and the corresponding thermodynamic properties of metal ions have been found. These data were utilized to evaluate the solute-characteristic parameters of the revised Helgeson–Kirkham–Flowers equation of state and to compute the thermodynamic properties of the dissociation reactions of metal–chromate complexes at high temperatures and pressures.  相似文献   
64.
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   
65.
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   
66.
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   
67.
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   
68.
69.
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   
70.
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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