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21.
利用区域气候模式RegCM3模拟2000年我国黑碳气溶胶的分布特征和辐射强迫。结果表明,黑碳气溶胶主要分布在我国黄河以南、青藏高原以东的广大区域,柱含量由南向北递减;柱含量最大值在0.6mg/m^2以上,出现在中南、四川盆地、湖南、贵州、广西、广东西部和云南南部等地区;青藏高原南侧黑碳气溶胶次高值区的存在,反映了气溶胶的跨国界输送并影响区域气候的特点。黑碳气溶胶的大气顶辐射强迫介于0.1—0.8w/m^2之间,地表辐射强迫介于-0.1— -2.0W/m^2之间,两者分布特征与柱含量分布特征基本一致。同柱含量相似,黑碳气溶胶大气顸辐射强迫和地表辐射强迫也有明显的季节性变化,春季最大,秋、冬季次之,夏季最小。 相似文献
22.
Giorgio Hadi Curti 《GeoJournal》2009,74(3):201-208
Ostensibly, subtitles in films serve as linguistic approximations of meaning. Expectedly then, much of the debate surrounding
subtitling has been concerned with representational accuracy, fidelity and authenticity. In this article I argue that by encountering
subtitles as affective bodily expressions, as opposed to approximate representations of pre-existent meanings or intentions,
filmic experiences may be(come) transformed and differently transformational. As a result, meaning and accuracy in subtitles
as superimposed signifiers or static representations become secondary to subtitles as spatially affective- and expressive-movements
intimately part of filmic scapes. The creative use of subtitling in Bekmambetov’s Russian language film Night Watch (Nochnoy dozor; 2006 [2004]) is discussed.
相似文献
Giorgio Hadi CurtiEmail: |
23.
《地震研究进展(英文)》2021,1(1):100005
Seismic anisotropy is an effective feature to study the inner structure of the Earth. In complex tectonic area, the assumption of single-layer anisotropy is sometimes not well consistent with the observed data; thus, the assumption of multi-layered (i.e. stratified) anisotropy should be considered. At present, the main methods to study anisotropy include receiver functions, shear wave splitting from local and teleseismic events (SKS, SKKS, and PKS, hereafter collectively called XKS), P- and Pn wave travel time inversion, surface wave inversion from far-field earthquakes and ambient noise. Each of the above method has its own advantages and limitations. Thus, one or more of the above methods are often combined to characterize multi-layered anisotropy, of which the depth range of anisotropic layers are different. This paper reviews the research progress of multi-layered anisotropy for the purpose of providing a basis for future seismic anisotropy investigations. 相似文献
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Based on the body strain record of Tiantanghe station from 2008 to 2014,we make a statistical analysis of the relationship between the maximum amplitude of the body strain record and the surface-wave magnitude,epicenter distance of the earthquakes,which occurred in the Chinese mainland and its surrounding areas with MS≥6. 0 and the rest of the world with MS≥7. 0. According to statistical results,we propose a statistical formula between the surface-wave magnitude of earthquake and the maximum amplitude of the body strain record,the epicenter distance: M_S~*= 0. 37 ln A_max+ 0. 57 ln D + 0. 07. We can also derive a theoretical estimation formula for the maximum amplitude: A_max=e~(2. 7(M_S~*-0. 07))D~(-1. 54). This demonstrates that the maximum amplitude of the body strain record increases exponentially with the increase of the surface-wave magnitude, and decreases with the increase of the epicenter distance,and shows a negative correlation with their product. We further discuss the necessity of adding instruments with high frequency sampling to earthquake monitoring, and dicuss the prospects for precise earthquake prediction in future. 相似文献
26.
In this paper, we give a brief introduction to the proposal and development history of the earthquake magnitude concept. Moment magnitude MW is the best physical quantity for measuring earthquakes. Compared with other magnitude scales used traditionally, moment magnitude is not saturated for all earthquakes, regardless of big and small earthquakes, deep and shallow earthquakes, far field and near field seismic data, geodetic and geological data, moment magnitude can be measured, and can be connected with well-known magnitude scales such as surface wave magnitude MS. Moment magnitude is a uniform magnitude scale, which is suitable for statistics with wide magnitude range. Moment magnitude is the preferred magnitude selected by the International Seismological community, and it is preferred by the departments responsible for publishing seismic information to the public.Moment magnitude is a uniform magnitude scale, which is suitable for statistics with wide magnitude range. Moment magnitude is a preferred magnitude for international seismology, it is preferred by the agency responsible for providing information about earthquakes to the public. We provide all formulas used in the calculation of moment magnitude, and the calculation steps in detail. We also analyzed some problems and rules to solve these problems by using different formulas and numerical value calculation steps. 相似文献
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28.
青藏高原东南缘地区是现今地壳形变和地震活动最强烈的地区之一,也是研究青藏高原现今变形机制和构造演化规律的重要区域.本研究使用云南区域地震台网的55个宽频带地震台站连续地震背景噪声数据,采用双台站互相关方法获得Rayleigh(瑞利)面波经验格林函数,提取相速度频散曲线,反演得到云南地区周期5~34s范围内方位各向异性分布图像.反演结果揭示:短周期(5~12s)Rayleigh面波快波优势方向与区域断裂走向有很好的一致性,快波方向随着断裂走向的变化而变化.周期16~26s快波优势方向与反映上地壳特性的5~12s图像总体图像相似,但细节略有不同.其中,滇中块体内易门断裂和滇中块体内东侧的普渡河断裂附近,各向异性快波方向从NS向NW方向旋转;易门断裂以西呈NW向.这反映了青藏高原物质东流和川滇块体受到青藏块体的南东向挤压作用.周期30~34s范围的各向异性,滇缅泰块体和印支块体,快波优势方向为NS和NNW向;而在滇中块体内部,各向异性快波方向呈顺时针旋转变化,可能与青藏高原物质向东逃逸有关.本文还开展了与体波各向异性的对比分析,通过与近震S波分裂、Pms转换波分裂和远震SKS、PKS和SKKS(以后简称为XKS)分裂的对比研究,发现随着周期的增大,得到的快波优势方向与XKS剪切波快波偏振方向趋向一致,与地壳快剪切波偏振方向呈一定夹角.本研究认为,青藏高原东南缘地区壳幔各向异性具有不同的特征和形成机制. 相似文献
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30.
Rengin Gök Hanan Mahdi Haydar Al-Shukri Arthur J. Rodgers 《Geophysical Journal International》2008,172(3):1179-1187
We report the crustal structure for two locations in Iraq estimated by joint inversion of P -wave receiver functions (RFs) and surface (Rayleigh) wave group velocity dispersion. RFs were computed from teleseismic recordings at two temporary broad-band seismic stations located in Mosul (MSL) in the Zagros Fold Belt and Baghdad (BHD) in the Mesopotamian Foredeep. Group velocity dispersion curves at the sites were derived from continental-scale tomography. The inversion results show that the crustal thicknesses are 39 km at MSL and 43 km at BHD. We observe a strong Ps Moho at BHD consistent with a sharp Moho discontinuity. However, at MSL we observe a weak Ps Moho suggesting a transitional Moho where crustal thickening is likely to be occurring in the deep crust. Both sites reveal low velocity surface layers consistent with sedimentary thickness of about 3 km at station MSL and 7 km at BHD and agreeing well with the previous reports. Ignoring the sediments, the crystalline crustal velocities and thicknesses are remarkably similar at both stations. The similarity of crustal structure suggests that the crust of the northeastern proto-Arabian Platform was uniform before subsidence and deposition of the sediments in the Cenozoic. If crystalline crustal structure is uniform across the northern Arabian Platform then crustal thickness variations in the Zagros Fold Belt and Thrust Zone should reveal the history of deformation and crustal shortening in the Arabian–Eurasian collision zone and not reflect pre-existing crustal thickness variations in the Arabian Plate. 相似文献