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1.
Kim I. S. Krusanova N. L. Popov V. V. Osokin A. R. Mironova I. V. 《Geomagnetism and Aeronomy》2020,60(4):441-445
Geomagnetism and Aeronomy - The color of the coronal continuum was determined from observations in order to search for manifestations of coronal expansion. A brief review of studies determining the... 相似文献
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Theoretical and Applied Climatology - Indian summer monsoon rainfall (ISMR) variability of ± 10% of its long-term mean leads to flood and drought, affecting the life and economic... 相似文献
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Denton Callander Julie Mooney-Somers Phillip Keen Rebecca Guy Tim Duck Benjamin R. Bavinton 《International journal of geographical information science》2020,34(11):2160-2176
ABSTRACT Gay men and lesbian women often demonstrate unique settlement patterns, forming what have been referred to as ‘gayborhoods’. This study sought to provide the first postcode-level estimates of population size and prevalence of gay and lesbian people in Australia. Data on same-gender-partnered households from the Australian Census were combined with information from six different surveys conducted from 2011 to 2017. We estimated that in 2016 there were 132,203 gay men (1.5% of adult males; 95% CI: 1.4–1.6) and 79,931 lesbian women (0.9% of adult females; 95% CI: 0.8–1.0) in Australia. While many postcodes were sparsely populated by gay and lesbian people (40.1% had prevalences of <0.1%), 24.6% were moderately populated (prevalences in the 50-95th percentile) and 2.7% were highly populated (95th percentile). By jurisdiction, the Australian Capital Territory had the highest prevalences of gay men (2.1%; 95% CI: 2.0–2.2) and lesbian women (1.5%; 95% CI: 1.4–1.6). Although the majority of highly populated postcodes were found in major cities (83.7%), some were also found in regional and remote area (16.3%). This method can be applied in other countries to enhance populate estimates. The accompanying dataset can be used to guide service delivery, conduct geographically contextualised research and develop policies relevant to gay men and lesbian women in Australia. 相似文献
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Natural Resources Research - Sand failure and production occurs when the formation stress exceeds the strength of the formation, which is derived majorly from the natural material that cements the... 相似文献
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Tumbure Akinson Bretherton Mike R. Bishop Peter Hedley Mike J. 《Natural Resources Research》2020,29(3):1561-1570
Natural Resources Research - The physical and chemical characteristics of mined phosphate rock will vary temporally as the location and nature of the ore body changes and as the type of equipment... 相似文献
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S. Akkar T. Azak T. Çan U. Çeken M. B. Demircioğlu Tümsa T. Y. Duman M. Erdik S. Ergintav F. T. Kadirioğlu D. Kalafat Ö. Kale R. F. Kartal K. Kekovalı T. Kılıç S. Özalp S. Altuncu Poyraz K. Şeşetyan S. Tekin A. Yakut M. T. Yılmaz M. S. Yücemen Ö. Zülfikar 《Bulletin of Earthquake Engineering》2018,16(8):3197-3228
A review on the historical evolution of seismic hazard maps in Turkey is followed by summarizing the important aspects of the updated national probabilistic seismic hazard maps. Comparisons with the predecessor probabilistic seismic hazard maps as well as the implications on the national design codes conclude the paper. 相似文献
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The main focus of this paper is on uncertainties associated with the selection of the incoherency coefficient and apparent propagation velocity in the simulation of asynchronous seismic excitations based on the provisions of CEN [Comité Européen de Normalisation] (Eurocode 8: Design of structures for earthquake resistance—part 2: bridges, BS EN 1998-2:2005, Brussels, Belgium 2005). To this effect, the importance of utilizing appropriate values of these two parameters in the simulation of spatially varying seismic excitations is highlighted, and practice-oriented recommendations are provided for their selection. In addition, preliminary probability distributions are proposed for the consideration of the effect of uncertainty in the selection of the apparent propagation velocity for reliability (fragility) analyses. The effect of multi-support input motions on the seismic response of bridges is also discussed. 相似文献
10.
Taus R. C. Jrgensen Douglas K. Tinkham C. Michael Lesher 《Journal of Metamorphic Geology》2019,37(2):271-313
Low‐pressure and high‐temperature (LP–HT) metamorphism of basaltic rocks, which occurs globally and throughout geological time, is rarely constrained by forward phase equilibrium modelling, yet such calculations provide valuable supplementary thermometric information and constraints on anatexis that are not possible to obtain from conventional thermometry. Metabasalts along the southern margin of the Sudbury Igneous Complex (SIC) record evidence of high‐grade contact metamorphism involving partial melting and melt segregation. Peak metamorphic temperatures reached at least ~925°C at ~1–3 kbar near the SIC contact. Preservation of the peak mineral assemblage indicates that most of the generated melt escaped from these rocks leaving a residuum characterized by a plagioclase–orthopyroxene–clinopyroxene–ilmenite‐magnetite±melt assemblage. Peak temperatures reached ~875°C up to 500 m from the SIC lower contact, which marks the transition to metabasalts that only experienced incipient partial melting without melt loss. Metabasalts ~500 to 750 m from the SIC contact are characterized by a similar two‐pyroxene mineral assemblage, but typically contain abundant hornblende that overgrew clino‐ and orthopyroxene along an isobaric cooling path. Metabasalts ~750 to 1,000 m from the SIC contact are characterized by a hornblende–plagioclase–quartz–ilmenite assemblage indicating temperatures up to ~680°C. Mass balance and phase equilibria calculations indicate that anatexis resulted in 10–20% melt generation in the inner ~500 m of the aureole, with even higher degrees of melting towards the contact. Comparison of multiple models, experiments, and natural samples indicates that modelling in the Na2O–CaO–FeO–MgO–Al2O3–SiO2–H2O–TiO2–O2 (NCFMASHTO) system results in the most reliable predictions for the temperature of the solidus. Incorporation of K2O in the most recent amphibole solution model now successfully predicts dehydration melting by the coexistence of high‐Ca amphibole and silicate melt at relatively low pressures (~1.5 kbar). However, inclusion of K2O as a system component results in prediction of the solidus at too low a temperature. Although there are discrepancies between modelling predictions and experimental results, this study demonstrates that the pseudosection approach to mafic rocks is an invaluable tool to constrain metamorphic processes at LP–HT conditions. 相似文献