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81.
DUAN Yong-hong) ZHANG Xian-kang) LIU Zhi) XU Zhao-fan)WANG Fu-yun) PAN Ji-shun)LIANG Guo-jing) ) Geophysical Exploration Center China Earthquake Administration Zhengzhou China ) Longgang Volcano Observatory Earthquake Administration of Jilin Province Fusong China 《地震学报(英文版)》2007,(5)
Twenty broadband seismographs were deployed along Hongyuan, Sichuan to Wuwei, Gansu. 81 teleseismic events were recorded in one year. We computed receiver functions from teleseismic waveform data and obtained S wave velocity structure beneath each station along the profile by using receiver function inversion method. The results revealed that the crustal structure is very complex and crustal average S wave velocity is to be on the low side. Low velocity structure generally exists in the depth range of 10~40 km in the crust between Aba arc fault and northern edge fault of Qinling earth’s axis and it is a tectonic feature of complex geological process such as ancient A’nyêmaqên Tethys ocean from closing and side colliding to subducted plate exhumed or thrust rock slice lifted. The Moho is about 50 km depth along the profile and is slightly deeper in the south than in the north. 相似文献
82.
A new kind of composite pile named Concrete-cored DCM (Deep-Cement-Mixing) pile is introduced for supporting medium loads
in soft clay ground. This composite pile is composed of an inner precast concrete pile and an external DCM pile socket, where
the high strength concrete pile is designed to bear the load of building, and DCM pile socket acts to transfer axial force
into the surrounding soils by skin frictions. In this paper we introduce its application in soft ground, and tentatively investigated
its bearing capacity and settlement using static loading tests and Finite Element Method. Our study indicates that concrete-cored
DCM pile acts as a friction pile and is an economical and effective method for settlement control and capacity improvement
in soft clay ground. This study is also valuable for research on the mechanism of other composite piles.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
83.
84.
讨论了电子地图支持下的控制网设计,将地理环境信息、网优化设计理论、技术设计规程相融合,介绍了“大地网技术设计系统”的基本功能,从技术角度探讨了其软件开发的4个关键技术。此类软件的开发和应用,可以代替测量规范中有关技术设计部分的操作;这也是大地测量生产中软件开发向可视化和支持质量控制发展的方向。 相似文献
85.
本文介绍了环斑结构的含义及奥长环斑花岗岩的地质与地球化学特征。在此基础上对所谓的秦岭奥长环斑花岗岩带提出质疑,并提出秦岭中的一些花岗岩虽然具有环斑结构,但不是奥长环斑花岗岩。 相似文献
86.
87.
河南不同成因类型铝土矿的矿石特征 总被引:4,自引:0,他引:4
本文在对铝土矿石物质组成研究的基础上,运用电子显微镜(EM)对河南两类不同类型铝土矿床的矿石结构进行了观察研究。根据EM观察到的铝土矿石显微结构的不同形貌特征,划分出三种矿石结构类型:致密-隐晶结构、粒状镶嵌结构和粒屑结构。由此归结为两个成因类型:古风化壳异地堆积亚型和古风化壳原地堆积亚型的铝土矿床。 相似文献
88.
Featuresofisostaticgravityanomalyandseis┐micactivityintheCentralAsianregionSHENG-MINGFANG1)(方盛明)RUIFENG2)(冯锐)CHANG-ZHENGTIAN... 相似文献
89.
宁波大桥主墩墩址软弱带成因机制研究 总被引:1,自引:1,他引:1
通过对宁波大桥主墩墩址软弱带详细的地质勘测和综合方法研究,内中包括粘土泥质物X射线衍射分析,软弱带岩石化学成分和不同成因砂和砾石的成分和特征研究,特别是软弱带的显微构造和物质来源的研究,本文对这一软弱带的成因机制着重进行了探讨。研究发现,这一软弱带在结构上可划分为三部分或三层结构,下部为挤压破碎带、中部为风化产物、上部为地表水贯入充填堆积。它表明这一软弱带经历了三种不同的地质作用的演化过程或具有三种物质来源。这一研究结论对大桥的设计和施工有重要的影响和意义。 相似文献
90.
Zhou Xuesong Song Songyan Zhang Xiankang Qiu Shuyan Gong Yi and Song JianliResearch Center of Exploration Geophysics SSB Zhengzhou China 《中国地震研究》1998,(1)
By processing S-wave data from the Fanshi-Huai'an-Taipusiqi DSS profile,which is a three-component,wide-angle reflection/refraction profile,and in the light of the results from P-wave interpretation,two-dimensional(2-D)structures of the crust and upper mantle are presented,including S-wave velocity Vs and the physical parameter of medium-Poisson's ratio a.Taking other geological and geophysical information into account,and with reference to the results from petrophysical experiments at home and abroad,we carried out interpretation and inference with respect to deep crustal structure,tectonics,and lithologic characters.It has been concluded that in the upper and middle crust,a values are mostly not greater than 0.25,and rocks,which generally assume brittle,are mainly composed of granite; the rocks in the lower layer of the upper crust between Yangyuan-Huai'an containing inorganic CO2 itself releases carbon; for the rocks in the lower crust and crust-mantle transitional zone,which are comparatively plasti 相似文献