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1.
VognimaryMarieOdette 《地球空间信息科学学报》2005,8(2):152-156
This paper focuses on the public participation in environmental planning. After the decade for inaccessible information related to the decision taken, actually, the program of public parti,cipation is the reference of all the decision making process. However, there are some factors that limit this process, such as poverty, illiteracy, ignorance and often the social inequality. Therefore, this study focuses first on the benefits of public participation in environmental planning, then the involvement of the local population, and finally the decision making access using a case study of Madagascar. 相似文献
2.
Rare earth element variations resulting from inversion of pigeonite and subsolidus reequilibration in lunar ferroan anorthosites 总被引：1，自引：0，他引：1
We present results of a secondary ion mass spectrometry study of the rare earth elements (REEs) in the minerals of two samples of lunar ferroan anorthosite, and the results are applicable to studies of REEs in all igneous rocks, no matter what their planet of origin. Our pyroxene analyses are used to determine solid-solid REE distribution coefficients (D = CREE in low-Ca pyroxene/CREE in augite) in orthopyroxene-augite pairs derived by inversion of pigeonite. Our data and predictions from crystal-chemical considerations indicate that as primary pigeonite inverts to orthopyroxene plus augite and subsolidus reequilibration proceeds, the solid-solid Ds for orthopyroxene-augite pairs progressively decrease for all REEs; the decrease is greatest for the LREEs. The REE pattern of solid-solid Ds for inversion-derived pyroxene pairs is close to a straight line for Sm-Lu and turns upward for REEs lighter than Sm; the shape of this pattern is predicted by the shapes of the REE patterns for the individual minerals.Equilibrium liquids calculated for one sample from the compositions of primary phases, using measured or experimentally determined solid-liquid Ds, have chondrite-normalized REE patterns that are very slightly enriched in LREEs. The plagioclase equilibrium liquid is overall less rich in REEs than pyroxene equilibrium liquids, and the discrepancy probably arises because the calculated plagioclase equilibrium liquid represents a liquid earlier in the fractionation sequence than the pyroxene equilibrium liquids. “Equilibrium” liquids calculated from the compositions of inversion-derived pyroxenes or orthopyroxene derived by reaction of olivine are LREE depleted (in some cases substantially) in comparison with equilibrium liquids calculated from the compositions of primary phases. These discrepancies arise because the inversion-derived and reaction-derived pyroxenes did not crystallize directly from liquid, and the use of solid-liquid Ds is inappropriate. The LREE depletion of the calculated liquids is a relic of formation of these phases from primary LREE-depleted minerals. Thus, if one attempts to calculate the compositions of equilibrium liquids from pyroxene compositions, it is important to establish that the pyroxenes are primary. In addition, our data suggest that experimental studies have underestimated solid-liquid Ds for REEs in pigeonite and that REE contents of liquids calculated using these Ds are overestimates.Our results have implications for Sm-Nd age studies. Our work shows that if pigeonite inversion and/or subsolidus reequilibration between augite and orthopyroxene occurred significantly after crystallization, and if pyroxene separates isolated for Sm-Nd studies do not have the bulk composition of the primary pyroxenes, then the Sm-Nd isochron age and εNd will be in error. 相似文献
3.
James M.D. Day Richard J. Walker Odette B. James Igor S. Puchtel 《Earth and Planetary Science Letters》2010,289(3-4):595-605
Coupled 187Os/188Os and highly siderophile element (HSE: Os, Ir, Ru, Pt, Pd, and Re) abundance data are reported for pristine lunar crustal rocks 60025, 62255, 65315 (ferroan anorthosites, FAN) and 76535, 78235, 77215 and a norite clast in 15455 (magnesian-suite rocks, MGS). Osmium isotopes permit more refined discrimination than previously possible of samples that have been contaminated by meteoritic additions and the new results show that some rocks, previously identified as pristine, contain meteorite-derived HSE. Low HSE abundances in FAN and MGS rocks are consistent with derivation from a strongly HSE-depleted lunar mantle. At the time of formation, the lunar floatation crust, represented by FAN, had 1.4 ± 0.3 pg g? 1 Os, 1.5 ± 0.6 pg g? 1 Ir, 6.8 ± 2.7 pg g? 1 Ru, 16 ± 15 pg g? 1 Pt, 33 ± 30 pg g? 1 Pd and 0.29 ± 0.10 pg g? 1 Re (～ 0.00002 × CI) and Re/Os ratios that were modestly elevated (187Re/188Os = 0.6 to 1.7) relative to CI chondrites. MGS samples are, on average, characterised by more elevated HSE abundances (～ 0.00007 × CI) compared with FAN. This either reflects contrasting mantle-source HSE characteristics of FAN and MGS rocks, or different mantle–crust HSE fractionation behaviour during production of these lithologies. Previous studies of lunar impact-melt rocks have identified possible elevated Ru and Pd in lunar crustal target rocks. The new results provide no supporting evidence for such enrichments.If maximum estimates for HSE in the lunar mantle are compared with FAN and MGS averages, crust–mantle concentration ratios (D-values) must be ≤ 0.3. Such D-values are broadly similar to those estimated for partitioning between the terrestrial crust and upper mantle, with the notable exception of Re. Given the presumably completely different mode of origin for the primary lunar floatation crust and tertiary terrestrial continental crust, the potential similarities in crust–mantle HSE partitioning for the Earth and Moon are somewhat surprising. Low HSE abundances in the lunar crust, coupled with estimates of HSE concentrations in the lunar mantle implies there may be a ‘missing component’ of late-accreted materials (as much as 95%) to the Moon if the Earth/Moon mass-flux estimates are correct and terrestrial mantle HSE abundances were established by late accretion. 相似文献
4.
Odette Conchon 《Progress in Oceanography》1987,18(1-4)
The stratigraphy of Quaternary marine sediments in Corsica is summarised: Holocene (Versilian) deposits occur at 2–5m and last interglacial sediments (Tyrrhenian Stage) from 2 to 10–15m altitude. Locally, two older deposits, up to 30–40m above present sea-level, indicate the first transgressive phase of the last interglacial stage, and the penultimate interglacial stage.Sections are described where Quaternary hydrodynamic conditions were different from present ones in the same locality. At some sites which are high energy at present, sand deposits and sandstones provide evidence of low or medium energy conditions during the last interglacial and the penultimate interglacial stages. These variations correlate with sea-level changes, particularly at Cala d'Ancone, where sedimentation occurred during the transgressive phase of the interglacial stage, and where cementation terminated during the subsequent regressive phase.The occurrence of pebbles in localities where low energy conditions prevail at present, probably represent fluvial material reworked by wave action, during the last as well as the penultimate interglacial stages.Local variations in hydrodynamic intensity correlate with sea-level changes along the western Corsican shore, although general energy conditions remained constant throughout the interglacial stages. 相似文献
5.
The heating of cholestanol 2a with kaolinite (140°C, 16 hr) mainly leads to a mixture of steranes (40%) and sterenes (35%). The major compounds which are formed have been identified as 5α(H)- and 5β(H)-cholestanes, 4a and 4b, the diacholestenes, 5, the diacholestanes, 6, and the D-homodiacholestanes 7. With the exception of the latter, these compounds have all been observed previously in ancient sediments and crude oils. Several of these compounds are identical or bear structural similarities with those obtained from cholestanol at low temperature in acidic or superacidic conditions. The comparison with the results obtained using other minerals (montmorillonite, talc, alumina, polyphos-phate-treated montmorillonite) shows that the observed transformations are catalysed by superacid sites which are present in kaolinite and montmorillonite. 相似文献
6.
Ecosystem-based management of fisheries: is science limiting? 总被引：4，自引：0，他引：4
Frid Chris L.J.; Paramor Odette A.L.; Scott Catherine L. 《ICES Journal of Marine Science》2006,63(9):1567-1572
7.
Full waveform inversion aims to use all information provided by seismic data to deliver high-resolution models of subsurface parameters. However, multiparameter full waveform inversion suffers from an inherent trade-off between parameters and from ill-posedness due to the highly non-linear nature of full waveform inversion. Also, the models recovered using elastic full waveform inversion are subject to local minima if the initial models are far from the optimal solution. In addition, an objective function purely based on the misfit between recorded and modelled data may honour the seismic data, but disregard the geological context. Hence, the inverted models may be geologically inconsistent, and not represent feasible lithological units. We propose that all the aforementioned difficulties can be alleviated by explicitly incorporating petrophysical information into the inversion through a penalty function based on multiple probability density functions, where each probability density function represents a different lithology with distinct properties. We treat lithological units as clusters and use unsupervised K-means clustering to separate the petrophysical information into different units of distinct lithologies that are not easily distinguishable. Through several synthetic examples, we demonstrate that the proposed framework leads full waveform inversion to elastic models that are superior to models obtained either without incorporating petrophysical information, or with a probabilistic penalty function based on a single probability density function. 相似文献
8.
Vognimary Odette 《地球空间信息科学学报》2013,16(2):152-156
This paper focuses on the public participation in environmental planning. After the decade for inaccessible information related to the decision taken, actually, the program of public participation is the reference of all the decision making process. However, there are some factors that limit this process, such as poverty, illiteracy, ignorance and often the social inequality. Therefore, this study focuses first on the benefits of public participation in environmental planning, then the involvement of the local population, and finally the decision making access using a case study of Madagascar. 相似文献
9.
With advancing climate change there is a growing need to include short-lived climate forcings in cost-efficient mitigation strategies to achieve international climate policy targets. Tools are required to compare the climate impact of perturbations with distinctively different atmospheric lifetimes and atmospheric properties. We present a generic approach for relating the climate effect of short-lived climate forcers (SLCF) to that of CO2 emissions. We distinguish between three alternative types of metric-based factors that can be used to derive CO2 equivalences for SLCF: based on forcing, activity and fossil fuel consumption. We derive numerical values for a wide range of parameter assumptions and apply the resulting generalised approach to the practical example of aviation-induced cloudiness. The evaluation of CO2 equivalences for SLCF tends to be more sensitive to SLCF specific physical uncertainties and the normative choice of a discount rate than to the choice of a physical or economic metric approach. The ability of physical metrics to approximate economic-based metrics alters with changing atmospheric concentration levels and trends. Under reference conditions, physical CO2 equivalences for SLCF provide sufficient proxies for economic ones. The latter, however, allow detailed insight into structural uncertainties. They provide CO2 equivalences for SLCF in short term strategies in the face of failing climate policies, and a temporal evolution of CO2 equivalences over time that is noticeably better in line with cost-efficient climate stabilisation. 相似文献
10.
Odette B. JAMES Barbara A. COHEN Lawrence A. TAYLOR Mikhail A. NAZAROV 《Meteoritics & planetary science》2007,42(6):1029-1032
Abstract We described lunar meteorite Dhofar 026 (Cohen et al. 2004) and interpreted this rock as a strongly shocked granulitic breccia (or fragmental breccia consisting almost entirely of granulitic‐breccia clasts) that was partially melted by post‐shock heating. Warren et al. (2005) objected to many aspects of our interpretation: they were uncertain whether or not the bulk rock had been shocked; they disputed our identification of the precursor as granulitic breccia; and they suggested that mafic, igneous‐textured globules within the breccia, which we proposed were melted by post‐shock heating, are clasts with relict textures. The major evidence for shock of the bulk rock is the fact that the plagioclase in the lithologic domains that make up 80–90% of the rock is devitrified maskelynite. The major evidence for a granulitic‐breccia precursor is the texture of the olivine‐plagioclase domain that constitutes 40—45% of the rock; Warren et al. apparently overlooked or ignored this lithology. Textures of the mafic, igneous‐textured globules, and especially of the vesicles they contain, demonstrate that these bodies were melted and crystallized in situ. Warren et al. suggested that the rock might have originally been a regolith breccia, but the textural homogeneity of the rock and the absence of solar wind—derived noble gases preclude a regolith‐breccia precursor. Warren et al. classified the rock as an impact‐melt breccia, but they did not identify any fraction that was impact melt. 相似文献