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31.
利用2016—2018年3期华北地区流动地磁矢量原始测量资料, 经数据计算获得2期华北地区和张家口—渤海地震活动带及邻区岩石圈磁场时空变化模型。 研究结果显示: 张家口—渤海地震带岩石圈磁场变化空间分布不均匀, 具有明显的分区特征, 在张家口段(西段)与北京段(中西段)分界处和北京段(中西段)与唐山段(中东段)分界处岩石圈磁场各要素具有明显的异常变化, 如水平矢量存在转向和幅值变化, 磁偏角与磁倾角具有正负异常高梯度带的特征, 这与张家口—渤海地震带构造分段性特征密切相关。 张家口—渤海地震带位于燕山块体与华北平原块体之间, 两者运动的平动速率之差是张家口—渤海地震带左旋走滑的直接动力来源, 而各断裂带左旋走滑速率之差很可能是岩石圈磁场空间变化分段性分布的主要原因。 相似文献
32.
黑龙江多宝山——大新屯地区铜金多金属成矿作用及找矿方向 总被引:1,自引:0,他引:1
黑龙江省多宝山—大新屯地区,铜矿以中—晚加里东期多宝山式斑岩型、燕山早期三矿沟式矽卡岩型为主,晚古生界海底火山岩有关喷发—沉积型铜锌矿床,具优越的成矿潜力,不同时期、类型铜矿床在空间分布上明显受古生代海相火山岩—碳酸盐岩建造控制,并具有"上金下铜"的斑岩—热液型铜金矿成矿系统的特征。金矿以燕山晚期三道湾子式浅成低温热液型金成矿作用强烈为特点;持续时间由早石炭世—早—中侏罗世的韧性剪切—走滑作用、中侏罗世为主要伸展期的变质核杂岩有关的金成矿作用,以及奥陶纪浊积岩(卡林型)有关金成矿作用,以中—小规模金矿床(点)为主;金矿受北西向、北东向的火山构造、变质核杂岩构造和韧性剪切—走滑作用控制,显示出良好的金找矿前景;结合近期的铜金矿重大勘查进展和成果,总结成矿规律,梳理了制约着铜金多金属矿找矿突破的关键地质问题,提出找矿方向和今后勘查工作部署建议。 相似文献
33.
Tom Jacob 《Climate Policy》2013,13(1):91-97
What is the significance of the 2007 United Nations Climate Change Conference in Bali? The formal outcomes, especially the ‘Bali Action Plan’, are described and commented on, along with the challenges for negotiating a post-2012 agreement in Copenhagen during 2008 and 2009. The article concludes that the outcome of the Bali meeting is insufficient when compared to the nature of the challenge posed by climate change. However, it can nevertheless be considered a success in terms of ‘Realpolitik’ in paving the way for the negotiations ahead, because some real changes have been discerned in the political landscape. The challenges for the road towards Copenhagen are manifold: the sheer volume and complexity of the issues and the far-reaching nature of decisions such as differentiation between non- Annex I countries pose significant challenges in themselves, while the dependency on the electoral process in the USA introduces a high element of risk into the whole process. The emergence of social justice as an issue turns climate policy into an endeavour to improve the world at large—thereby adding to the complexity. And, finally, the biggest challenge is the recognition that the climate problem requires a global solution, that Annex I and non-Annex I countries are mutually dependent on each other and that only cooperation regarding technology in combination with significant financial support will provide the chance to successfully tackle climate change. 相似文献
34.
《Climate Policy》2013,13(3):221-231
Abstract Five years down the road from Kyoto, the Protocol that bears that city's name still awaits enough qualifying ratifications to come into force. While attention has been understandably focussed on the ratification process, it is time to begin thinking about the next steps for the global climate regime, particularly in terms of a deeper inclusion of developing countries' concerns and interests. This paper begins doing so from the perspective of the developing countries. The principal argument is that we need to return to the basic principles outlined in the Framework Convention on Climate Change in searching for a north—south bargain on climate change. Such a bargain may be achievable if we can realign the policy architecture of the climate regime to its original stated goals of sustainable development. 相似文献
35.
《Climate Policy》2013,13(3):298-316
The impacts of predicted climate change will not be distributed evenly around the world. As post-Kyoto negotiations unfold, relating the geographical distribution of projected impacts to responsibility for emissions among world regions is essential for achieving an equitable path forward. This article surveys the current knowledge of regional climate consequences, and delves into the regional predictions of economic assessment models to date, examining how the uncertainties, assumptions and ethical dimensions influence the portrayal of risk at this scale. The few studies that quantitatively compared regional risk and responsibility are reviewed, and the analytical framework from one such study is applied to the 2006 Stern Review's projections to give the first regional comparison to take purchasing power and welfare considerations into account. Synthesizing burden and blame in this way is informative for policy makers; the world's most vulnerable communities—in Africa, the Indian subcontinent, Latin America, and small island states—accounted for less than 33% of global greenhouse gas emissions over the period 1961–2000, but may experience more than 75% of the ensuing climate damages this century. This analysis reinforces the call for industrialized nations to lead mitigation efforts, and to do so decisively and swiftly. 相似文献
36.
37.
B. E. Sabogal R. E. Mennickent G. Pietrzyski W. Gieren 《Monthly notices of the Royal Astronomical Society》2005,361(3):1055-1062
We present a catalogue with coordinates and photometric data of 2446 Be star candidates in the Large Magellanic Cloud (LMC), based on a search of the OGLE II data base. The I -band light curves of these stars show outbursts in 24 per cent of the sample (Type-1 stars), high and low states in 10 per cent, periodic variations in 6 per cent (Type-3 stars), and stochastic variations in 60 per cent of the cases. We report on the result of the statistical study of light curves of Type-1 and Type-3 stars in the LMC, and the comparison with the previously reported results of the Small Magellanic Cloud (SMC) sample. We find a statistically significant difference between amplitude, duration and asymmetry distributions of outbursts in both galaxies. Outbursts of SMC Type-1 stars are usually brighter, longer and with a slower decline. We find a bimodal distribution of periods of Type-3 stars in both galaxies, probably related to the recently discovered double periodic blue variables. We find also period and amplitude distributions of Type-3 LMC stars statistically different from those of the SMC stars. Our findings above suggest that the mechanisms causing the observed photometric variability of Type-1 and Type-3 stars could depend on metallicity. Moreover, they suggest that the outbursts are not primarily caused by stellar winds. 相似文献
38.
39.
We study analytically the Rayleigh–Taylor instability in expanding supernova gas shell. The instability appears at the inner
shell surface accelerated by blowing pulsar wind. The most dangerous perturbations correspond to wavelengths comparable to
the shell thickness. We analyze the fragility of the supernova remnant shell in function of the initial perturbation amplitude
and the shell thickness. 相似文献
40.