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ON THE PRESENT UPLIFT SPEED OF QING-ZANG PLATEAU

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Chinese Science Bulletin 1991年第21期36卷 1820-1824页

作者：张青松周耀飞陆祥顺徐秋六 Institute of Geography Academia Sinica Beijing 100101 PRC First Geodesic Team of Shaanxi Province National Bureau of Surveying and Mapping Xi'an 710054 PRC

Uplift of Qing-Zang (Qinghai-Xizang (Tibet)) Plateau and its impacts on the natural environment and human activities is one of the most important subjects of global changes. Chinese and foreign geoscientists presented quite a lot of different ideas on the time and amplitude of the uplift of the Qing-Zang Plateau in the past decades of years. E. Norin real-

关键词： uplift rate Qing-Zang Plateau repeated measurement of precise leveling network

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12点调平系统及其应急预案措施

Aerospace China 2023年第3期24卷 31-37页

作者： LIU Yu ZHANG Shuai HE Jianhua ZHU Miaoxin ZENG Yi ZHOU Li Beijing Institute of Space Launch Technology Beijing 100076

With high stability,strong bearing capacity and other characteristics,multi-point leveling systems have been widely used in various *** mobile platform here uses a 12-point leveling system,which is mainly composed of the mechanical transmission system of the supporting arm,a hydraulic drive system and an electrical control *** leveling is realized through the proportional lifting of the arms in four *** order to ensure the smooth conduct of launch missions,emergency plans were made for the leveling system incase of failure of a single arm.

关键词： multi-point leveling system supporting arm emergency operation leveling 12-point

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浅谈三角高程测量方法及精度分析

测绘与空间地理信息 2010年第6期33卷 215-216,220+223页

作者：崔克忠吉林省地理信息工程院吉林长春130051

分析了一般的三角高程测量方法的局限性,在实践中总结了一种便捷的三角高程测量的新方法。同时还论证了用三角高程测量代替三、四等水准测量的理论依据,并采用全站仪任意置站的方法,测量时不必量取仪器高、棱镜高,既减少了三角高程的误... 详细信息

分析了一般的三角高程测量方法的局限性,在实践中总结了一种便捷的三角高程测量的新方法。同时还论证了用三角高程测量代替三、四等水准测量的理论依据,并采用全站仪任意置站的方法,测量时不必量取仪器高、棱镜高,既减少了三角高程的误差来源,又加快了施测速度。

关键词：三角高程测量测量方法精度分析 Accuracy Analysis Trigonometric leveling Method of 四等水准测量误差来源理论依据仪器高新方法全站仪棱镜高局限性总结速度实践

基于MATLAB的GPS水准拟合方法的应用及比较

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测绘与空间地理信息 2010年第6期33卷 137-139,142页

作者：康英平中石油工程设计有限公司青海分公司甘肃敦煌736202

近年来GPS大地水准面精化已经成为测绘领域的热点问题。由于MATLAB的矩阵特点,本文首先对GPS水准的原理及常见的几种拟合方法进行了介绍,然后采用MATLAB语言分析几种拟合方法的特点及适用性,通过实例得出结论与建议。

关键词： MATLAB语言 GPS水准拟合拟合方法 GPS leveling Methods of Comparison Application 大地水准面精化特点热点问题测绘领域适用性矩阵分析

Surface-deformation monitoring in the permafrost regions over the Tibetan Plateau,using Sentinel-1 data

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Research in Cold and Arid Regions 2018年第2期10卷 114-125页

作者： ZhenMing Wu Lin Zhao Lin Liu Rui Zhu ZeShen Gao YongPing Qiao LiMing Tian HuaYun Zhou MeiZhen Xie Cryosphere Research Station on the Qinghai-Tibetan Plateau State Key Laboratory of Cryospheric SciencesNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouGansu 730000China University of Chinese Academy of Sciences Beijing 100049China Earth System Science Programme Faculty of ScienceThe Chinese University of Hong KongShatinHong Kong 999077China Faculty of Geomatics Lanzhou Jiaotong UniversityLanzhouGansu 730070China

Differential Interferometric Synthetic Aperture Radar(D-In SAR) has been widely used to measure surface deformation over the Tibetan Plateau. However, the accuracy and applicability of the D-In SAR method are not well estimated due to the lack of in-situ validation. In this paper, we mapped the seasonal and long-term displacement of Tanggula(TGL) and Liangdaohe(LDH) permafrost regions with a stack of Sentinel-1 acquisitions using the Small Baseline Subset In SAR(SBAS-In SAR) method. In the TGL region, with its dry soils and sparse vegetation, the In SAR-derived surface-deformation trend was consistent with ground-based leveling results; long-term changes of the active layer showed a settlement rate of around 1 to 3 mm/a due to the melting of ground ice, indicating a degrading permafrost in this area. Around half of the deformation was picked up on monitoring, in contrast with in-situ measurements in LDH, implying that the D-In SAR method remarkably underestimated the surface-deformation. This phenomenon may be induced by the large soil-water content, high vegetation coverage, or a combination of these two factors in this region. This study demonstrates that surface deformation could be mapped accurately for a specific region with Sentinel-1 C-band data, such as in the TGL ***, although the D-In SAR technology provides an efficient solution for broad surface-deformation monitoring in permafrost regions, it shows a poor performance in the region with high soil-water content and dense vegetation coverage.

关键词： deformation permafrost SBAS-InSAR leveling Sentinel-1 Tibetan Plateau

Unification of national surveying vertical datum

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中国有色金属学会会刊：英文版 2005年第S1期15卷 9-12页

作者： YIN Xiao-dong~(1, 2), HU Jia-sheng~1, ZHANG Li-hua~2, LI Shu-jun~2 (1. School of Telecommunication, Dalian University of Technology, Dalian 116024, China 2. Department of Ocean Surveying, Dalian Naval Academy, Dalian 116018, China)

The vertical datum of China is composed of leveling datum for heights and chart datum for depths. The determination of national leveling datum and its disadvantages were discussed firstly. The local mean sea level and chart datum with its guarantee rate of navigation safety were studied secondly. The models of unification of national surveying vertical datum, such as optimization model of mean sea level, adoption of New Chinese quasi-geoid of 2000(CQG2000) and time-invariant global geoid were suggested finally.

关键词： vertical datum leveling datum chart datum geoid quasi-geoid

Ground Subsidence Following Groundwater Drawdown by Excavating of 500 m Deep Investigation Shafts in Granite Body in Mizunami, Central Japan in 2004-2012

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Engineering（科研） 2015年第7期7卷 424-433页

作者： Fumiaki Kimata Yasuhiro Asai Ryo Honda Toshiyuki Tanaka Hiroshi Ishii Rikio Miyajima Tono Research Institute of Earthquake Science Association for the Development of Earthquake Prediction Gifu Japan

Two 500 m deep investigation shafts were excavating in the granite body in Mizunami, central Japan by JAEA (Japan Nuclear Cycle Development Institute) in 2004-2012. Groundwater with volume of 700 m3 was generally pumping a day to prevent the shafts from submerging in 2012 following the excavating. As a result of pumping the groundwater, the ground water level lowered to 60 m in the borehole with the distance of 200 m from the excavating shafts in 2012. leveling network extending 2 km × 2 km around the shafts was established to detect the vertical deformation around the shafts in 2004, and precise leveling was done every year. An 18 mm ground subsidence was detected in the benchmark close to the shafts for 8 years in 2004-2012, and time series of subsidence at benchmark was consistent with the groundwater drawdown. The groundwater drawdown and ground subsidence were caused by the pumping ground water in excavating shafts.

关键词： Ground Subsidences Groundwater Drawdown 500 m Deep Excavation Shaft Precise leveling Groundwater Drainage

Preparatory mechanism of Ms8.0 Wenchuan earthquake evidenced by crust-deformation data

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Geodesy and Geodynamics 2011年第2期2卷 23-28页

作者： Bo Wanju Yang Guohua Zhan Wei Zhang Fengshuang Wan Wenni Zhang Licheng First Crust Monitoring and Application Center Tiaajin 300180 China

Some crustal-deformation data related to the Ms8.0 Wenchuan in 2008, was described and a model that is capable of explaining the observed deformation features is presented. The data include ： pre-earthquake uplift in an area south of the epicenter obtained by repeated-leveling measurements ; pre-earthquake horizontal deformation by GPS observation during two periods in Sichuan-Yunnan area;vertical deformation along a short cross-fault leveling line in the epicenter area; and co-seismic near-field vertical and horizontal crustal-move- ment data by GPS. The model is basically ＂elastic-rebound＂, but involves a zone between two local faults that was squeezed out at the time of earthquake. ：

关键词： Wenchuan Ms8.0 earthquake earthquake generation mechanism deformation leveling GPS

The Application of GNSS to Fault Deformation Studies

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Earthquake Research in China 2014年第4期28卷 510-519页

作者： Bo Wanju Feng Shengtao Su Jianfeng Zhou Haitao Du Xuesong Wan Wenni Liu Tianhai The First Crustal Deformation Monitoring and Application Center CEA National Earthquake Response Support Service

Great earthquakes often occur along or near active fault belts. Thus,monitoring and research on fault deformation are quite important. Methods such as short-leveling,shortbaseline and integrated monitoring profile across fault belts have been used to monitor fault activities for many years. GNSS observations are mainly used to obtain the horizontal velocity field in large areas and to study the activities and deformation of major *** technology has been used to monitor and study the deformation of faults from a different aspects. In this paper,some applications and new explorations of GNSS are discussed. They are:( 1) Research and monitoring of strike-slip activities of faults with GNSS.( 2) Research and monitoring of vertical activities of faults with GNSS.( 3)Investigating the laws of deformation of blocks on the sides of fault zone and setting up strain models to deduce the activities and deformation of faults with respective models and compare the deduced results with the actual measurements across fault. It is concluded that a larger discrepancy between the deduced and the observed deformation indicates a stronger interaction between the blocks,which can be important for predicting the location of a strong earthquake and assessing seismic hazard,as well as the seismicity trend.

关键词： GNSS Fault deformation Baseline leveling Seismicity Crust block