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761.
应用黑龙江省数字遥测地震台网2002-2006年目录数据,对绥棱采石场附近爆破进行重新定位,对比GPS实测位置,研究该黑龙江省数字地震台网“十五”数据处理软件系统(MSDP 人机交互系统)提供的5种定位程序,初步认为,对于网内浅源地震定位,单纯型法优于其他方法。 相似文献
762.
The seismic demand parameters including the floor acceleration amplification (FAA) factors and the interstory drift ratios (IDRs) were acquired from the floor response in time history analysis of a tall building subjected to selected ground motions. The FAA factors determined in this way are larger than those given in most current code provisions, but the obtained IDRs are close to the values given in some code provisions. Imposing a series of in‐plane pre‐deformations to two glass curtain wall (CW) specimens mounted on a shaking table, the IDRs were reproduced and the FAA factors were satisfied through applications of computed floor spectra compatible motion time histories, whose peak accelerations corresponded to the FAA factors. The CW specimens performed well during the whole experimental program with almost no change in the fundamental frequencies. No visible damage was observed in the glass panels. The maximum stresses detected in each component of the CW system were smaller than the design strengths. The obtained component acceleration amplification factor approached 3.35, which is larger than the value given in the current code provisions. In conclusion, the performance of the studied CW system is seismically safe. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
763.
Land cover is one of the most basic input elements of land surface and climate models. Currently, the direct and indirect effects of land cover data on climate and climate change are receiving increasing attentions. In this study, a high resolution (30 m) global land cover dataset (GlobeLand30) produced by Chinese scientists was, for the first time, used in the Beijing Climate Center Climate System Model (BCC_CSM) to assess the influences of land cover dataset on land surface and climate simulations. A two-step strategy was designed to use the GlobeLand30 data in the model. First, the GlobeLand30 data were merged with other satellite remote sensing and climate datasets to regenerate plant functional type (PFT) data fitted for the BCC_CSM. Second, the up-scaling based on an area-weighted approach was used to aggregate the fine-resolution GlobeLand30 land cover type and area percentage with the coarser model grid resolutions globally. The GlobeLand30-based and the BCC_CSM-based land cover data had generally consistent spatial distribution features, but there were some differences between them. The simulation results of the different land cover type dataset change experiments showed that effects of the new PFT data were larger than those of the new glaciers and water bodies (lakes and wetlands). The maximum value was attained when dataset of all land cover types were changed. The positive bias of precipitation in the mid-high latitude of the northern hemisphere and the negative bias in the Amazon, as well as the negative bias of air temperature in part of the southern hemisphere, were reduced when the GlobeLand30-based data were used in the BCC_CSM atmosphere model. The results suggest that the GlobeLand30 data are suitable for use in the BCC_CSM component models and can improve the performance of the land and atmosphere simulations. 相似文献
764.
The excavated height of the left bank slope of the diversion power system intake in Jinchuan hydropower station is about 16o m. The stability and safety of the slope during construction and its operation/utilization become one of the most important geological engineering problems. At the same time, it is also crucial to select a safe and economic excavation gradient for the construction. We studied the problem of how to select a safe and economic slope ratio by analyzing the geological condition of the high slope, including the lithology, slope structure, structural surface and their combinations, rock weathering and unloading, hydrology, and the natural gradient. The study results showed that the use of an excavation gradient larger than the gradient observed during site investigation and the gradient recommended in standards and field practice manuals is feasible. Then, we used the finite element method and rigid limit equilibrium method to evaluate the stability of the excavation slope under natural, rainstorm and earthquake conditions. The calculated results showed that the excavated slope only has limited failure, but its stability is greatly satisfactory. The research findings can be useful in excavation and slope stabilization projects. 相似文献
765.
通过录井、测井、地震、野外剖面与岩心资料的深入剖析, 探讨中上扬子地区下志留统页岩段的沉积相与总有机碳的关系, 预测页岩气有利勘探区。中上扬子地区下志留统龙马溪组为一套20~268 m厚的黑色页岩夹灰绿色泥质粉砂岩沉积, 在等时框架内自下而上可识别出2个三级层序即SQ1与SQ2, 它们分布稳定、可对比性好。下部层序(SQ1) 的海侵体系域(TST)发育一套有利于页岩气形成的富有机质页岩, 此时期呈现出“北面向次深海敞开、东西南三面受古陆围限、陆棚广布”的沉积格局, 深水陆棚相广泛发育, 面积为255000 km2, 平均厚度35 m。受海平面下降的影响, 从下部层序至上部层序水体变浅, 岩相从深水陆棚相黑色页岩向中-浅水陆棚相沙纹层理粉砂质页岩转变。岩相的发育受海平面升降、古陆、海底地形、物源供给等因素的影响, 岩相类型有碳质或硅质或钙质页岩、纹层状页岩、生物扰动粉砂质页岩、沙纹层理的粉砂质页岩、块状砂岩或介壳灰岩薄夹层5类。研究表明, 沉积相对富有机质页岩的形成具有内在的控制作用, 高TOC含量页岩发育于深水陆棚相、中陆棚相和潟湖相中。目前, 已有多口井在龙马溪组页岩获得工业气流, 揭示了该区良好的页岩气勘探前景;综合分析认为涪陵-赤水-仁怀、威远-长宁、鄂西-渝东为中上扬子地区下志留统页岩气勘探的主要方向和有利目标区。 相似文献
766.
?????θ???????????С??GPS/?????????????????????????????????????????????????????????????????????????????????????????????澫???????????Ч???? 相似文献
767.
Bin Zhao Wei Wang Shaomin Yang Maolei Peng Xuejun Qiao Ruilin Du Zhaosheng Nie 《Journal of Seismology》2012,16(2):305-313
This study estimates the far field coseismic deformation of China and its surrounding areas caused by the Mw9.0 Tohoku earthquake
of Japan using continuous GPS (cGPS) data and final orbits released by International GNSS Service (IGS). Based on these data,
we feature the coseismic offsets of several plates affected by the event. Static far field coseismic offsets greater than
2 mm are detected in a wide area of China, which extends as far as about 3,000 km off the epicenter, consisting of that of
the 2010 Maule, Chile earthquake. In northeast China, displacements up to 32.7 mm toward southeast are observed; meanwhile,
offsets in North China reach about 5–11 mm toward east. Coseismic jumps of about 2–5 mm are measured in South China toward
southeast. The southwest extrusion of the Philippine Sea plate is verified by GPS slip vectors, showing that the Philippine
Sea plate is decoupled from the Pacific plate by the earthquake. We also infer that the Amurian plate and the Okhotsk plate
couple well according to relatively continuous GPS offsets in these plates. Furthermore, the dense far field cGPS offsets
due to the Tohoku event hopefully provide opportunities to model the coseismic slip distribution. 相似文献
768.
769.
建立基于地壳不均匀的三维有限元模型,将昆仑山口西Ms8.1地震产生的长约400 km的破裂带在走向上分为16段,生成各个破裂段滑移相对于地表位移的格林函数,并以GPS观测的水平位移为约束,用阻尼最小二乘法反演破裂滑移分布,结果表明反演结果与地质考察的地表破裂数据接近.用反演结果重构的地表位移场与观测值一致,并体现了断裂... 相似文献
770.
分析国家重力基准的现状,对国家重力基准的建立和维护提出建议. 相似文献