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After describing briefly some of the outstanding features of the uncommonly cold and wet year 1695, one of the coldest years
of the Little Ice Age, an annotated translation is presented of a contemporary review of the unusual weather events of the
year in Europe. The original was published in 1702 in Frankfurt am Main, Germany, in vol. XIV of the seriesTheatrum Europaeum. The annotation relates to the historical events of the year that were substantially affected by the weather, events to which
rather abstruse references are made in the aforementioned contemporary account. In addition to the fact that the contemporary
review describes the uncommon weather conditions of 1695, it appears to be the first extended weather review in history. 相似文献
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26.
Kornerupine in Mg-Al-rich gneisses from Namaqualand,South Africa: mineralogy and evidence for late-metamorphic fluid activity 总被引:1,自引:0,他引:1
Three kornerupine occurrences are reported in distinctive SiO2-poor, MgO- and Al2O3-rich paragneisses from the Namaqualand Metamorphic Complex in South Africa. Kornerupine coexists stably with phlogopite, cordierite, orthopyroxene, gedrite, sapphirine, sillimanite and plagioclase and, in sapphirine-free rocks, with spinel and corundum. Tourmaline of a texturally older generation than kornerupine is commonly present in the same samples.Ten analysed kornerupines show a variation in total Fe as FeO from 1.8 to 10.9 weight per cent. B2O3 contents are estimated from x-ray data and a few spectrochemical analyses to range from 0.9 to 3.5 weight per cent. There is a strong inverse correlation between B3+ and Al3+. Total iron content has a strong and systematic effect on refractive index, colour and dispersion. Fe and Mg are systematically partitioned with the other minerals, and Mg/(Mg+Fe) ratios increase as follows: spinel 相似文献
27.
Sedimentology and kinematics of a large, retrogressive growth-fault system in Upper Carboniferous deltaic sediments, western Ireland 总被引:2,自引:0,他引:2
Growth faulting is a common feature of many deltaic environments and is vital in determining local sediment dispersal and accumulation, and hence in controlling the resultant sedimentary facies distribution and architecture. Growth faults occur on a range of scales, from a few centimetres to hundreds of metres, with the largest growth faults frequently being under‐represented in outcrops that are often smaller than the scale of feature under investigation. This paper presents data from the exceptionally large outcrops of the Cliffs of Moher, western Ireland, where a growth‐fault complex affects strata up to 60 m in thickness and extends laterally for ≈ 3 km. Study of this Namurian (Upper Carboniferous) growth‐fault system enables the relationship between growth faulting and sedimentation to be detailed and permits reconstruction of the kinematic history of faulting. Growth faulting was initiated with the onset of sandstone deposition on a succession of silty mudstones that overlie a thin, marine shale. The decollement horizon developed at the top of the marine shale contact for the first nine faults, by which time aggradation in the hangingwall exceeded 60 m in thickness. After this time, failure planes developed at higher stratigraphic levels and were associated with smaller scale faults. The fault complex shows a dominantly landward retrogressive movement, in which only one fault was largely active at any one time. There is no evidence of compressional features at the base of the growth faults, thus suggesting open‐ended slides, and the faults display both disintegrative and non‐disintegrative structure. Thin‐bedded, distal mouth bar facies dominate the hangingwall stratigraphy and, in the final stages of growth‐fault movement, erosion of the crests of rollover structures resulted in the highest strata being restricted to the proximity of the fault. These upper erosion surfaces on the fault scarp developed erosive chutes that were cut parallel to flow and are downlapped by the distal hangingwall strata of younger growth faults. 相似文献
28.
Distribution of the trace elements Cr, Cu, Ni, Pb and Zn in surficial sediments of the river/sea environment in Danang –
Hoian area (Vietnam) was investigated to examine the degree of metal pollution caused by anthropogenic activities. Point sources
from domestic and industrial wastes are identified as dominant contributors of trace element accumulation. Surficial sediments
of Hoian River show extremely high total concentrations of Cu (Average Concentration 295 μg/g), Ni (AC 112 μg/g), Pb (AC 396 μg/g)
and Zn (AC 429 μg/g) that exceed assigned safety levels ER-M. Similarly, the sediments of Han River show high Pb (AC 188 μg/g)
and Zn (AC 282 μg/g) contents. In marine sediments of Thanhbinh beach Pb is also enriched (138 μg/g) above guideline levels.
In contrast the sediments of the Cude River are dominated by trace element concentrations close to background values.
Received: 17 December 1998 · Accepted: 6 May 1999 相似文献
29.
Simone Carr-Cornish Peta Ashworth John Gardner Stephen J. Fraser 《Climatic change》2011,107(3-4):549-565
There is a large body of research and development into the low emission energy technologies that has the potential to assist developed and developing countries transition to more sustainable energy systems. It has long been recognised that public perceptions can have a fundamental effect on the market for technology and this issue raises questions about the role society will play in developing a low emissions energy future. Understanding how the public will respond to the range of low emission energy technologies as part of a climate change mitigation package is therefore critical for researchers, policy makers and industry stakeholders. In the current research, we investigated the Australian public’s likely acceptance of a range of low emission energy technologies by assessing the diverse ‘orientations’ that have emerged in response to low emission energy technologies. In a survey of two Australian states we measured the support for, and knowledge of, a range of low emission energy technologies. Using self-organising maps, a relatively new approach for segmenting response profiles, we identified that at least four distinct ‘orientations’ have emerged toward the issue and are characterising the likely acceptance of these technologies: ‘Disengaged’, ‘Nuclear Oriented’, ‘Renewables Oriented’, and ‘Engaged’. The implications of these multiple public viewpoints are described for climate change mitigation policy and for future research into the social acceptance of alternative energy technologies. 相似文献
30.
Marcos E. C. Bernardes Mark A. Davidson Keith R. Dyer Ken J. George 《Ocean Dynamics》2006,56(3-4):186-197
The main objective of this paper is to address the principal mechanisms involved in the medium-term (order of months to years) morphodynamic evolution of estuaries through the application of a process-based numerical modelling. The Teign estuary (Teignmouth, UK) is the selected site. The system is forced by the macrotidal semi-diurnal tide in the English Channel and is perturbed to a minor extent by high river discharge events (freshets). Although waves have a definite influence on the adjacent coastal area, Wells (Teignmouth Quay Development Environmental Statement: Changes to Physical Processes. Report R.984c:140. ABP Marine Environmental Research Ltd., Southampton, 2002b) suggested that swell waves do not enter the estuary. Hence, wave effects are neglected in this study, as only tides and the river discharge are taken into account. The sediment grain size is highly variable, but mainly sandy. Within the frame of the COAST3D project (), four bathymetric surveys of the adjacent coastal area were carried out at a nearly weekly intervals. The outer estuary and the adjacent coastal area were also surveyed every 6 months as part of the COASTVIEW project (). Based on these data and on continuously measured parameters, such as water level, waves, wind and river discharge, numerical modelling of the morphodynamic processes can be tested. To replicate the morphological changes in the medium-term within a feasible simulation time, forcing conditions are reduced through the use of an input reduction method (called ensemble technique). In this study, simulations are based on the coupling between Telemac-2D and its non-cohesive sediment transport module, Sisyphe (version 5.3 for both modules). Three different sediment transport formulae were tested: (1) Engelund and Hansen (A monograph on sediment transport in alluvial streams, 3rd edn. Technological University of Denmark, Copenhagen, 1967) including the modifications proposed by Chollet and Cunge (J Hydraul Eng 17(1):1–13, 1979); (2) Bijker (Mechanics of sediment transport by the combination of waves and current. In: Design and reliability of coastal structures. 23rd international conference on Coastal Engineering, pp 147–173, 1968) and (3) Soulsby (Dynamics of Marine Sands. A manual for practical applications. HR Wallingford, Wallingford, p 142, 1997) modified version of van Rijn [J Hydraul Eng 110(10):1431–1456, 1984a, J Hydraul Eng 110(11):1613–1641, 1984b] formulation. Both a qualitative (i.e. visual comparison) and a quantitative tool [Brier Skill Score (BSS); described in Sutherland et al. in Coast Eng 51:917–939, 2004b] are applied to assess the similarity of simulations when compared to model predictions and observations. Tests confirmed the reliability and time efficiency of the ensemble technique, since it reproduced very well the results of a reference run, a computation based on the observed boundary conditions. For the spring-neap cycle modelled, the BSS was of 0.91 (a perfect modelling would have a BSS of 1), with a reduction in the simulation time on the order of 80%. For the 6-month-period simulation, results were also excellent: BSS=0.92 and a computer time reduction of 85%. In principle, this method has the advantage of being applied to any process-based numerical model. 相似文献