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151.
关于1937年菏泽7级地震成因的探讨 总被引:2,自引:0,他引:2
本文以三维空间角度,从菏泽地震的地震构造环境、构造应力场、震源闭锁形式和地震玻裂机制等方面探讨了菏泽地震的成因。提出了断裂空间交汇闭锁模式和共轭破裂发震机制,分析了菏泽地震发生在聊考断裂的东侧、濮阳——开封上地幔隆起东翼的原因。 相似文献
152.
Wenyuan Cui Jianrong Shi Yuanyuan Geng Caixia Zhang Xiaoying Meng Lang Shao Bo Zhang 《Astrophysics and Space Science》2013,346(2):477-492
In order to get a broader view of the s-process nucleosynthesis we study the abundance distribution of heavy elements of 35 barium stars and 24 CEMP-stars, including nine CEMP-s stars and 15 CEMP-r/s stars. The similar distribution of [Pb/hs] between CEMP-s and CEMP-r/s stars indicate that the s-process material of both CEMP-s and CEMP-r/s stars should have a uniform origin, i.e. mass transfer from their predominant AGB companions. For the CEMP-r/s stars, we found that the r-process should provide similar proportional contributes to the second s-peak and the third s-peak elements, and also be responsible for the higher overabundance of heavy elements than those in CEMP-s stars. Which hints that the r-process origin of CEMP-r/s stars should be closely linked to the main r-process. The fact that some small r values exist for both barium and CEMP-s stars, implies that the single exposure event of the s-process nucleosynthesis should be general in a wide metallicity range of our Galaxy. Based on the relation between C r and C s, we suggest that the origin of r-elements for CEMP-r/s stars have more sources. A common scenario is that the formation of the binary system was triggered by only one or a few supernova. In addition, accretion-induced collapse(AIC) or SN 1.5 should be the supplementary scenario, especially for these whose pre-AGB companion with higher mass and smaller orbit radius, which support the higher values of both C r and C s. 相似文献
153.
汶川大地震汉源县城建筑物震害调查 总被引:2,自引:0,他引:2
汶川地震中,距离震中约200公里的汉源县出现了明显烈度异常现象,汉源县城建筑物震害表现尤为明显.为了解释这一现象,在汶川大地震第一阶段科学考察中,相关调查小组对汉源县城建筑物震害开展了相应的调查.调查结果表明,该处烈度异常现象确实存在,烈度异常与该处局部场地条件有一定的联系. 相似文献
154.
YANG ChuPeng GENG AnSong LIAO ZeWen SUN YongGe & ZHANG LüHui State Key Laboratory of Organic Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Graduate University of Chinese Academy of Sciences Beijing 《中国科学D辑(英文版)》2009,52(1):12-21
Gas washing has been known in the Tazhong area of the Tarim Basin, but its quantitative assessment has not yet been reported.
Here the influence of gas washing fractionation in the area was discussed based on the gas chromatogram data of 68 oils and
the results of the mixing experiments of a black oil and a condensate. The results show that the intensity of gas washing
fractionation decreased generally from northern to southern part and vertically from deep reservoirs to shallow reservoirs.
The gas washing fractionation was mainly controlled by fault systems in this area, with the increase of n-alkane mass depletion positively correlated to the number and scale of faults. Gas washing fractionation appears to have
affected the hydrocarbon property, and as a result the diversity of the crude oils is markedly controlled by gas washing.
In addition, the occurrence of waxy oil in this area may be resulted from multiple factors including gas washing, mixed filling
and migration fractionation.
Supported by National Basic Research Program of China (Grant No. 2006CB202303) and the National Natural Science Foundation
of China (Grant No. 40672091) 相似文献
155.
Preliminary analysis of the hanging wall effect and velocity pulse of the 5.12 Wenchuan earthquake 总被引:3,自引:2,他引:1
A preliminary study of the PGA attenuation, hanging wall effect and velocity pulse characteristics from the 2008 Wenchuan earthquake of Ms =8.0 is described in this paper. The study was carried out through analyses in the time and frequency domains of main earthquake records. In the PGA attenuation study, records from 316 stations less than 1000 km from the surface rupture of the fault were used as a database and attenuation relationships were developed and compared with some existing relationships that are widely used in mainland China, Chinese Taiwan and the US. At the same time, records from 28 stations less than 100 km from the fault were used to study the hanging wall effect and velocity pulse characteristics of this earthquake based on the distribution of PGA, PGV, spectral acceleration, and the velocity pulse peak, and the results are compared with the 1999 Chi-Chi earthquake. In addition, the large PGAs of the UD components observed in this event are also discussed in this paper. From the results of the preliminary study, some conclusions are developed and suggestions for further research are proposed. 相似文献
156.
大城市中心区的商业和房地产开发,既随着城市功能外溢而分化,又随着中心城区的二次开发而重构.以越秀区第一次全国经济普查和分别针对消费者和社区居民的两次问卷调查数据为基础,以街道为基本分析对象,通过空间和行为分析等方法,发现中心城区商业业态与房地产开发具有2个层面的含义:一是商业业态空间下商业配套与居住的关系,二是城市化进程下商业与房地产开发的关系.从第一层含义看,人口的空间分异和居民的消费习惯,解释了商业与房地产开发的空间分异、商业中心的业态构成与房地产开发的关系、社区商业发育程度与房地产开发的关系.从第二层含义看,地价的空间差异和政府的规划行为导向,成为影响商业与房地产开发关系的深层原因,巨大的经济效益差异型塑了商业业态和房地产空间.特别是在旧城区,商业与房地产一体开发下的商业设施,已经不再是传统单纯的配套功能.以购物中心、高档商住大厦、高档商业办公楼为代表的商业新形态通过引导房地产开发,直接加速了城市化的进程. 相似文献
157.
四川广元地质景观类型及其形成条件与综合评价 总被引:2,自引:0,他引:2
广元境内地质景观主要集中分布于四个区中,即广元区、剑门关区、唐家河区和七里峡区,以岩溶地貌、丹霞地貌、典型地质剖面和水体景观为主,具有独特性、典型性、科学性和系统性、浓厚的历史文化性等特征。受构造条件、成景地层和流水侵蚀作用方式不同的影响,广元区以岩溶地貌和水体景观为主,剑门关区以丹霞地貌为主,唐家河区以地质构造剖面和变质岩剖面为主,七里峡区以岩溶地貌为主。按资源价值、景点规模与组合、环境状况和旅游条件等对四个区的地质景观进行综合评价,认为目前广元区和剑门关区具备构建国家地质公园的基本条件,唐家河区和七里峡区具备构建中型省级地质公园的基本条件。 相似文献
158.
冀西北石榴基性麻粒岩中辉石的演化及其地质意义 总被引:2,自引:0,他引:2
冀西北石榴基性麻粒岩中的辉石可分为三个世代。第一世代的单斜和斜方辉石包裹于石榴石变斑晶中,
它们形成的温压条件为 T=750~830℃, P=1.0~1.26GPa。第二世代的单斜和斜方辉石分布于基质中,
它们和斜长石常构成120°交角的稳定共生结构, 形成条件 T=780~860℃,
P=0.83~0.92GPa。第三世代的辉石产于石榴石的冠状反应边内, 形成条件
T=720~750℃, P=0.554~0.679GPa。从第一世代单斜辉石到第三世代单斜辉石,
它们的Al 相似文献
159.
分析了多种金字塔数据结构的生成方法,比较了不同方法在影像匹配中的优劣,并提出了一种影像金字塔生成的快速算法。 相似文献
160.
江面平流雾的数值研究 总被引:2,自引:0,他引:2
本文利用二维平流雾模式研究了海上暖湿空气平流到长江冷水面上形成平流雾的过程,对影响平流雾形成的两个主要因子(水面温度水平梯度和平流风速)与平流雾区的关系进行了数值研究,为江面平流雾的预报提供了思路. 相似文献