迈入新千年的大地测量学——第22届IUGG大会有关大地测量部分的技术总结   总被引：1，自引：0，他引：1  

陈俊勇  魏子卿  胡建国  杨元喜  李建成  朱耀仲  许才军  孙和平  罗志才  吴斌  文汉江  查明 《测绘学报》2000,(1)

本文较系统地介绍了１９９９年７月在英国伯明翰举行的第２２届ＩＵＧＧ大会反映出来的大地测量的最新进展情况。全文共分４个部分：卫星定位技术的新进展,地球重力场的研究进展,地球动力学的新进展及大地测量理论与方法新进展。对其中若干领域,还提出我国今后发展的建议。  相似文献   

武汉和京都台站超导重力仪高精度潮汐重力观测结果     

孙和平  竹本修三  许厚泽  东敏博  向井厚志 《测绘学报》2000,29(2)

利用高精度潮汐重力场观测研究地球物理学和地球动力学问题已成为当今地学工作者的共识.由于某些信号十分微弱且具有区域和全球分布特征,相当一部分信号被混合在常规仪器的观测噪声水平上,因此获得全球分布的第一手高精度观测资料显得尤为重要.超导重力仪具有精度高,连续性和稳定性好等特征,期望能在测定区域和全球重力场的精细结构方面发挥重要作用.有18个台站参加的全球地球动力学合作项目于1997年7月份开始实施,其主要目的是解决诸如固体潮、地核近周日晃动、核模、地球自转和极移,地球和大气海洋的耦合机理以及由构造运动引起的重力场变化等热点问题.我们曾研究过中比法三国的超导重力仪潮汐观测资料,获得了欧洲和亚洲不同地区潮汐常数及分布特征.本文将利用武汉和日本京都三台超导重力仪观测资料研究亚洲地区大陆和海岛上的潮汐波振幅因子和相位滞后的时间变化特征以及各参数的误差估计等,同时将检测由大气和海潮变化产生的重力信号.文章分数据处理方法、潮汐参数测定、大气重力信号、海潮重力信号、潮汐参数的时间变化、非潮汐重力场变化特征等几方面叙述.  相似文献   

CRUSTAL CONFIGURATION OF NW HIMALAYA: EVIDENCES FROM THE ISOSTATIC AND FLEXURAL ANALYSIS OF GRAVITY DATA     

Satyaprakash  Paramesh BanerjeeWT  ”BX 《地学前缘》2000,(Z1)

CRUSTAL CONFIGURATION OF NW HIMALAYA: EVIDENCES FROM THE ISOSTATIC AND FLEXURAL ANALYSIS OF GRAVITY DATA  相似文献   

临猗ML5.0级地震前后的重力场变化及预报过程   总被引：1，自引：0，他引：1  

李清林  秦建增  黄邦武  张瑞敏  王雷  张建志 《华北地震科学》2000,18(4):13-19

讨论了气压、地形变、降雨和地下水位变化对重力观测资料的影响,论证了观测资料的可靠程度,在此基础之上结合地质构造,地壳深浅构造等资料,讨论了１９９８年７月１１日临猗地震前后重力场的变化;依据临猗地震前重力场的变化,结合该地区的地震活动性,对这次地震作出了预报。  相似文献   

京郊门城镇地面塌陷危险性研究   总被引：4，自引：0，他引：4  

慎乃齐  张杰坤  连建发  赵波  纪玉杰  陈铁军 《现代地质》2000,14(4):479-483

采空地面塌陷是门城镇地区危害性最严重的地质灾害类型。根椐实地勘察资料 ,论述了地面塌陷的分布特征和形成条件 ;选取与塌陷密切相关的 1 1个因素 ,采用二级模糊综合评判法对地面塌陷的危险度进行了分区预测。  相似文献   

中国北部深层构造之我见     

丁燕云  李占奎 《物探与化探》2000,24(1):17-22

根据新编制的1:200万重磁资料分析,中国北部深层存在东、中、西3个构造区,其东界在贺兰山-六盘山-龙门山一线,西界在星星峡-若羌一线。由此可见,东部范围包括华北-东部地区;中部包括蒙甘青地区;西部为塔里木-准噶尔地区。东、西部由中国最古老的2个太古代-早元古代稳定地块组成,而中部是元古代地块区,因受青藏高原的推挤,活动性较大。  相似文献   

Three-dimensional V_P and V_P /V_S models of the upper crust in the Friuli area (northeastern Italy)     

G. F. Gentile  G. Bressan  L. Burlini  & R. De Franco 《Geophysical Journal International》2000,141(2):457-478

3-D images of P velocity and P - to S -velocity ratio have been produced for the upper crust of the Friuli area (northeastern Italy) using local earthquake tomography. The data consist of 2565 P and 930 S arrival times of high quality. The best-fitting V _P and V _P / V _S 1-D models were computed before the 3-D inversion. V _P was measured on two rock samples representative of the investigated upper layers of the Friuli crust. The tomographic V _P model was used for modelling the gravity anomalies, by converting the velocity values into densities along three vertical cross-sections. The computed gravity anomalies were optimized with respect to the observed gravity anomalies. The crust investigated is characterized by sharp lateral and deep V _P and V _P / V _S anomalies that are associated with the complex geological structure. High V _P / V _S values are associated with highly fractured zones related to the main faulting pattern. The relocated seismicity is generally associated with sharp variations in the V _P / V _S anomalies. The V _P images show a high-velocity body below 6 km depth in the central part of the Friuli area, marked also by strong V _P / V _S heterogeneities, and this is interpreted as a tectonic wedge. Comparison with the distribution of earthquakes supports the hypothesis that the tectonic wedge controls most of the seismicity and can be considered to be the main seismogenic zone in the Friuli area.  相似文献   

The reduction of aliasing in gravity anomalies and geoid heights using digital terrain data   总被引：8，自引：0，他引：8  

W. E. Featherstone  & J. F. Kirby 《Geophysical Journal International》2000,141(1):204-212

Observations of gravity can be aliased by virtue of the logistics involved in collecting these data in the field. For instance, gravity measurements are often made in more accessible lowland areas where there are roads and tracks, thus omitting areas of higher relief in between. The gravimetric determination of the geoid requires mean terrain-corrected free-air anomalies; however, anomalies based only on the observations in lowland regions are not necessarily representative of the true mean value over the topography. A five-stage approach is taken that uses a digital elevation model, which provides a more accurate representation of the topography than the gravity observation elevations, to reduce the unrepresentative sampling in the gravity observations. When using this approach with the Australian digital elevation model, the terrain-corrected free-air anomalies generated from the Australian gravity data base change by between 77.075 and −84.335 mgal (−0.193 mgal mean and 2.687 mgal standard deviation). Subsequent gravimetric geoid computations are used to illustrate the effect of aliasing in the Australian gravity data upon the geoid. The difference between 'aliased' and 'non-aliased' gravimetric geoid solutions varies by between 0.732 and −1.816 m (−0.058 m mean and 0.122 m standard deviation). Based on these conceptual arguments and numerical results, it is recommended that supplementary digital elevation information be included during the estimation of mean gravity anomalies prior to the computation of a gravimetric geoid model.  相似文献   

Simplified seismic sidesway collapse analysis of frame buildings   总被引：1，自引：0，他引：1       下载免费PDF全文

Mohammadjavad Hamidia  Andre Filiatrault  Amjad Aref 《地震工程与结构动力学》2014,43(3):429-448

This paper presents the development and assessment of a simplified procedure for estimating the seismic sidesway collapse margin ratio of building structures. The proposed procedure is based on the development of a robust database of seismic peak displacement responses of nonlinear single‐degree‐of‐freedom systems for various seismic intensities and uses nonlinear static (pushover) analysis without the need for nonlinear time history dynamic analysis. The proposed simplified procedure is assessed by comparing its collapse capacity predictions on 72 different building structures with those obtained by nonlinear incremental dynamic analyses. The proposed simplified procedure offers a simple, yet efficient, computational/analytical tool that is capable of predicting collapse capacities with acceptable accuracy for a wide variety of frame building structures. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

综合物探方法在西安东郊地热勘测中的应用   总被引：1，自引：1，他引：0  

石建胜  金宜声 《物探与化探》1999,23(5):339-346

西安东郊灞河谷地处于骊山断隆西南斜坡上.利用MT、地震测深及重力测量结果综合解释了测区新生界的厚度,推断了隐伏断裂的性状及切割深度,选择了拟建地热井的新生界热储,并经钻探验证,取得了良好的地质效果.  相似文献