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71.
72.
依据1970年以来记录相对完备的MSge;5.0地震序列资料,统计研究了中国大陆余震分布尺度与序列最大地震震级M0及最大地震破裂形式之间的关系. 在95%置信概率下,考虑主震破裂形式, 分序列类型给出了余震分布尺度与M0之间的统计关系. 定性而言,余震分布尺度的对数lgR与M0正相关, 但数据分布较为离散. 分类型来看, 孤立型序列余震分布尺度与M0之间统计相关程度低, 余震分布尺度介于5~60 km之间; 主余型序列lgR与M0正相关; 多震型序列当M0le;6.2时lgR与M0之间相关性不显著,余震分布尺度介于5~70 km之间, 当M0ge;6.3时lgR与M0线性相关. 统计结果还表明, 走滑近走滑及斜滑型主震所导致序列类型比例之间没有显著差异,而倾滑近倾滑型主震(主要为逆断型破裂)所导致的主余型序列所占比例较高, 孤立型及多震型序列所占比例则相对较低. 对比研究显示, 当M0较高时,余震分布尺度主要取决于主震大小而与主震破裂形式关系不明显. 相似文献
73.
日本跨国公司对外直接投资区位研究 总被引:4,自引:2,他引:2
本文运用大量数据和资料对日本对外直接投资的地区结构和部门结构的变化、跨国公司对外直接投资的动机以及跨国公司海外生产基地的产品、市场结构特征进行详细分析,在此基础上总结了日本跨国公司对外直接投资的区位类型以及在不同区位类型下形成的企业内国际分工性质。 相似文献
74.
75.
将滇东北山原内会泽县土地按复合土地系统、土地系统、土地单元三级,划分为6个复合土地系统、20个土地系统和128个土地单元,分析了复合土地系统的自然特征. 相似文献
76.
The first author commenced his experiences with aerial photography in 1945, when he joined the Royal Air Force (RAF). The aerial cameras used at that time were the Williamson F24 and F52, with Ilford HP3 and FP3 panchromatic films. Subsequently the Williamson F95 camera was tested against the USAF Sonne 11 camera. During his final years in the RAF, a variety of film types was employed: colour, monochrome infra-red and false colour infra-red. Additional experience was gained when the author was employed by the International Training Centre (ITC), The Netherlands and he saw the further development of the air camera from the Wild RC8 and Zeiss (Oberkochen) RMK 15/23 to the Wild RC20, Zeiss (Jena) LMK and Zeiss (Oberkochen) RMK TOP. He predicts that the future lies with digital cameras.
The second author started working with aerial photography in the 1950s. Details are given of cameras, visual navigation sights and survey aircraft dating from that period. Overseas operations, carried out mainly by Hunting Surveys and Fairey Surveys, posed particular problems because the majority of the work there was undertaken without the aid of existing maps. The introduction of external navigation systems is described, from the Decca ship navigation system, through the GNS-200 VLF/Omega low frequency radio system to INS, the Inertial Navigation System. The author later joined the ITC, which enabled him to participate in trials of the Computer-controlled Photo Navigation System. Eventually practical experience was gained with differential GPS, particularly in countries in southeast Asia. Aerial photography currently appears to benefit less from financial investment than the photographic, aviation and survey industries. However, the satisfaction of making a significant contribution to major overseas development projects outweighs the frustration of lack of acceptance of plans for the future of the air survey industry. 相似文献
The second author started working with aerial photography in the 1950s. Details are given of cameras, visual navigation sights and survey aircraft dating from that period. Overseas operations, carried out mainly by Hunting Surveys and Fairey Surveys, posed particular problems because the majority of the work there was undertaken without the aid of existing maps. The introduction of external navigation systems is described, from the Decca ship navigation system, through the GNS-200 VLF/Omega low frequency radio system to INS, the Inertial Navigation System. The author later joined the ITC, which enabled him to participate in trials of the Computer-controlled Photo Navigation System. Eventually practical experience was gained with differential GPS, particularly in countries in southeast Asia. Aerial photography currently appears to benefit less from financial investment than the photographic, aviation and survey industries. However, the satisfaction of making a significant contribution to major overseas development projects outweighs the frustration of lack of acceptance of plans for the future of the air survey industry. 相似文献
77.
78.
用储层岩石抽提物的饱和烃色谱指纹识别油气层 总被引:12,自引:0,他引:12
利用储层岩石抽提物的饱和烃色 质总离子图的指纹特征判识储层的流体(油、气)类型。油层或油饱和的储层,饱和烃色 质总离子流图的特征是正构烷烃碳数分布宽,碳数分布在C15~C38之间,与原油样品的正构烷烃碳数分布相似;凝析气层的正构烷烃碳数分布略窄一些,碳数分布在C15~C35之间,低碳数(小于C21)的正构烷烃相对于油层富集,高碳数(大于C21)的正构烷烃丰度明显低于油层;干气层的正构烷烃碳数分布最窄,碳数分布在C15~ C28之间,只有低碳数的正构烷烃,高碳数的正构烷烃丰度极低。据此可用来识别油层、凝析气层和干气层,也可用于一些测井资料不全或测井质量差的老井的油气层复查、测井难以识别的火成岩油气层的识别,还可用于地层评价,为油气酸化层位的优选提供科学依据。 相似文献
79.
A nonlinear magnitude frequency equation has been derived in this paper on the assumption that all seismicity systems hold
fractal characteristics, and according to the differences of relevant coefficients in the equation, seismicity systems are
classified into two types: type I, the whole earthquake activity is controlled by only one great unified system; type II,
the whole earthquake activity is controlled by more than one great system. One type of seismicity system may convert to the
other type, generally. For example, a type I system will change to a type II system prior to the occurrence of a strong earthquake
in North China. This change can be regarded as an index for earthquake trend estimation. In addition, the difference between
b value in nonlinear magnitude frequency equation and that in linear equation and the term dΔM related to the coefficients of nonlinear terms obtained in this paper are proved to be a pair of available parameters for
medium short term earthquake prediction. 相似文献
80.
李相然 《吉林大学学报(地球科学版)》1998,(3)
滨海城市是我国国民经济和社会发展的重要地区,又处于大陆与海洋交界地带,地质环境比较脆弱。提出了滨海城市工程地质环境类型划分原理,将滨海城市按照工程地质环境特征划分为四大类型:即滨海平原型城市、滨海山地平原型城市、滨海平原山地型城市、滨海山地型城市,并对其工程地质环境特征进行了研究。 相似文献