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261.
为了分析大盛 -马站盆地的成因类型 ,重点调查了盆地内沉积相带的空间展布特征及盆地沉积中心迁移的规律 .盆地内同生构造显示盆地边缘主干断裂具有左行走滑特点 .盆地内生物化石及火山岩年代学特征表明盆地形成于早白垩世 .盆地性质为左旋走滑拉分盆地 ,说明郯庐断裂在早白垩世晚期发生过左旋走滑活动  相似文献   
262.
Phosphorites occurring at the bottom of the Cambrian system contain abundant small shelly fossils, which are the product of the first episode of life explosion in the Cambrian. It was previously reported that the small shelly fossils are dominated by hyolithids, olivooids, zhijinitids, conodontomorphs, yubelichitids, camenitids and algae, with minor amounts of sponge fossils. Large amounts of sponge spicules, diverse in form, have been found for the first time in the Gezhongwu Formation phosphorites at Shixing, Zhijin County, Guizhou Province, of which such spicules as diaxon-triactins, diaxon-tetractins, pentaxon-pentactins and hexon-hexactins account for 30%. These spicules constitute the sponge clastic phosphorites made up of sponge clastics. Meanwhile, it is also expected that the radiation and diversity of sponge animals started as early as in the earliest Early Cambrian. Habit and burying environment of sponge animal are discussed in the paper.  相似文献   
263.
鄂尔多斯南部地区早古生代被动大陆边缘特征与演化   总被引:7,自引:0,他引:7  
鄂尔多斯南部地区早古生代被动大陆边缘特征与演化@袁卫国@赵一鸣...  相似文献   
264.
区域水环境生态安全的预警系统构建初探   总被引:1,自引:0,他引:1  
谢钦铭  朱清泉 《江西科学》2008,26(1):37-42,49
通过对现阶段我国水环境生态安全问题的分析,探讨了实施区域水环境生态安全预警系统构建的重要意义,提出了预警系统建设的基本原则和主要思路,并勾画了预警系统的基本框架结构,其具体结构包括3个部分,即预警监测信息子系统、预警分析评价子系统和预警处理对策子系统。  相似文献   
265.
出使生涯对薛福成从洋务派向维新派的转变起了很关键的作用,其出使经历中的见闻、感悟大多被他记录在《出使四国日记》之中。通过对西方近代工商业的探究,薛福成深感发展商业对国家实现富强的作用;薛福成还亲身体验了近代民主政治制度,接触到了"议院"这个概念,提倡在国内实行君主立宪制,创办私营企业,学习近代民主政治,这表明薛福成转变为早期维新派。对近代工商业和民主政治的体验和考察是薛福成思想发生转变的重要原因。但是早期维新派自身的局限性使薛福成的思想中也有不少幼稚之处。  相似文献   
266.
Investigations of major marine and non-marine geologic and biotic events across the Triassic-Jurassic transition rely predominantly on detailed stratigraphic frameworks and biodiversity analyses. The alternating sequences of marine and terrestrial Triassic-Jurassic for- mations in Guangdong Province represent one of the most remarkable coal-bearing series in southern China. The Lower Jurassic Jinji Formation is widely distributed in Guangdong, with continuously outcropped sections and rich marine and non-marine fossil fauna. However, as little research has been conducted on fossil plant remains in the Jinji Formation, it is difficult to understand the systematics, diversity, and floral aspects of the Jurassic. Here we report on the recent collection of rich fossil plants from the Jinji Formation in the Dapeng area of Shenzhen, southern Guangdong Province. Our studies demonstrate taxonomical affiliations, preservation status, and diversity features of these plant fossils, which are marked by the close associ- ation of densely preserved, pinnae and rachis connected leaves, and the bennettitalean reproductive organs of Wil- liamsoniella, which may represent an Early Jurassic plant community dominated by Otozamites of the bennettitales. This work not only represents the first discovery of fossil plants in the Shenzhen area, but is also the first docu- mentation of Jurassic plants in Guangdong and the Pearl River Delta regions. Research related to these plant fossils will be helpful in the correlation of the Early Mesozoiccoal-bearing strata in Guangdong, and will provide a dee- per understanding of variations in plant diversity of the Triassic and Jurassic transition in southern China. Addi- tionally, it will provide terrestrial plant evidence for explorations in Jurassic palaeoecology, palaeoclimatology, and palaeogeography of southern China.  相似文献   
267.
A new genus and species of eutriconodont mammal, Chaoyangodens lii gen. et sp. nov., from the Dawangzhangzi bed of Yixian Formation, Lingyuan, Lia- oning, is reported. The new species has a tooth formula I5- C1-P1-M3/i4-cl-pl-m4, unique among eutriconodonts in having only one premolar in lower and upper jaws, respectively, and a distinctive diastema between the canine and the premolar. Its simple incisors and reduced premolars show a mosaic combination of primitive and derived fea- tures. This new taxon adds to the diverse group of Jehol eutriconodonts. Among the known species from at least three horizons, there seems no evolutionary trend in mor- phology that is recognizable, except for that larger species are all from the Lujiatun bed of the Yixian Fro. A thorough and systematic analysis involving all the Jehol eu- triconodonts is needed to understand their phylogenetic relationships.  相似文献   
268.
作为一种批评范式,现代意义上的中国作家论其实是在晚清与“五四”两代学者的共同努力下确立的.王国维与梁启超就是这一历史进程中的先驱者。首先,从历史语境来看,他们的文学观念已经发生了根本的变革;其次,他们都融合了中西思想观念,确立专门角度,讲究科学方法,已经具备了现代批评的质素;最后,他们的作家论既是对中国古代作家论的继承与超越,也对“五四”时代的作家论具有重要的启示意义。  相似文献   
269.
A large amount of carbonized plant remains were discovered in one of the outer burial pits of the Han Yangling Mausoleum, which was built more than 2000 years ago for the Jing Emperor, Liu, Qi (188―141 cal a BC), the fourth emperor of the Western Han Dynasty. The remains are identified by phytolith analysis and macrofossil morphological features. Seeds from foxtail millet (Setaria italica), broomcorn millet (Panicum miliaceum), rice (Oryza sativa) and chenopod (possible Chenopodium giganteum) are identified...  相似文献   
270.
渤海油田早期聚合物驱注入能力综合研究   总被引:2,自引:2,他引:0  
通过物理模拟实验研究不同注聚时机条件下注入能力的变化规律;在此基础上,结合渤海某油田实际数据,利用油藏数值模拟分析了渗透率、原油黏度、聚合物溶液黏度、注入速度和注入时机对注入压力的影响。运用中心组合试验设计方法设计50个试验样本,运用基于代理模型的方法建立注入压力与各因素之间的二次响应面数学模型并利用实际注聚井数据,对所建立的二次响应面数学模型进行检验,其相对误差小于10%,能够满足工程精度要求。  相似文献   
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