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The absolute gravity measurements from A10 along the 1240 km route in East Antarctica

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Science China Earth Sciences 2022年第12期65卷 2417-2420页

作者： yuande yang Fei LI Key Laboratory of Polar Surveying and Mapping Ministry of Natural Resources/Chinese Antarctic Center of Surveying and MappingWuhan UniversityWuhan 430079China

*** Gravity data provide significant insights on ice mass balance and geological structure studies in Antarctica,which is the largest ice sheet on the earth(Xu,2001;Alley et al.,2005).Since the 1950s,the gravity ties have been introduced to Antarctica from Australia and South America(Sledzinski,2001;Amalvict,2004),which adopted the approach of relative gravity measurements with pendulum or spring *** gravity measurements were later conducted in Antarctica by several countries to provide gravity bases and to derive its dynamic change with the technique advance in gravimeter *** 2009,25 absolute gravity surveys had been carried out at 14 stations in Antarctica(Mäkinen et al.,2007;E et al.,2007,2011;Kazama et al.,2013).

关键词： Antarctica East absolute

基于无人机正射影像的玉龙雪山白水河1号冰川末端冰裂隙提取

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冰川冻土 2024年第1期46卷 335-346页

作者：罗重鑫季青庞小平杨元德艾松涛茶明星王世金车彦军武汉大学中国南极测绘研究中心湖北武汉430079 中国科学院西北生态环境资源研究院冰冻圈科学国家重点实验室云南丽江玉龙雪山冰冻圈与可持续发展国家野外科学观测研究站甘肃兰州730000 安徽师范大学地理与旅游学院安徽芜湖241002 宜春学院江西宜春336000

冰川是冰冻圈的重要部分,对局地乃至全球气候变化响应敏感。冰裂隙作为冰川表面上显著的特征,对于认识冰川的状态、稳定性以及内部应力有着重要的作用。针对冰川冰裂隙高精度快速识别提取问题,本文以玉龙雪山白水河1号冰川为研究对象,... 详细信息

冰川是冰冻圈的重要部分,对局地乃至全球气候变化响应敏感。冰裂隙作为冰川表面上显著的特征,对于认识冰川的状态、稳定性以及内部应力有着重要的作用。针对冰川冰裂隙高精度快速识别提取问题,本文以玉龙雪山白水河1号冰川为研究对象,使用无人机航拍获取的0.12 m分辨率的正射影像,应用U-Net深度学习网络开展白水河1号冰川的冰裂隙的智能提取研究。使用U-Net网络提取冰裂隙的精度高于传统的Canny算子以及SVM算法,总体精度可高达93%,且U-Net网络泛化能力强。提取结果表明,白水河1号冰川冰裂隙主要为横向裂隙,伸展裂隙以及雁行裂隙,呈现随海拔降低,冰裂隙逐渐由横向裂隙变化为伸展裂隙的趋势,通过不同时期提取结果对比,发现冰裂隙数量和平均长度均有增加。基于无人机影像和深度学习方法的冰裂隙智能提取研究,可为监测冰川变化及其与气候变化的关系提供技术支撑。

关键词：冰裂隙无人机影像 U-Net 白水河1号冰川

Progressive fragmentation of granular assemblies within rockslides: Insights from discrete-continuous numerical modeling

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Journal of Mountain Science 2024年第4期21卷 1174-1189页

作者： JIANG Hui ZHOU yuande WANG Jinting DU Xiuli HUANG Hailong Key Laboratory of Urban Security and Disaster Engineering of Ministry of Education Beijing University of TechnologyBeijing 100124China. Key Laboratory of the Hydrosphere Sciences of the Ministry of Water Resources Tsinghua UniversityBeijing 100084China China Three Gorges Construction Management Co. Ltd.Chengdu 610000China

Rock fragmentation plays a critical role in rock avalanches,yet conventional approaches such as classical granular flow models or the bonded particle model have limitations in accurately characterizing the progressive disintegration and kinematics of multi-deformable rock blocks during *** present study proposes a discrete-continuous numerical model,based on a cohesive zone model,to explicitly incorporate the progressive fragmentation and intricate interparticle interactions inherent in *** rock granular assemblies are released along an inclined plane and flow onto a horizontal *** numerical scenarios are established to incorporate variations in slope angle,initial height,friction coefficient,and particle *** evolutions of fragmentation,kinematic,runout and depositional characteristics are quantitatively analyzed and compared with experimental and field data.A positive linear relationship between the equivalent friction coefficient and the apparent friction coefficient is *** general,the granular mass predominantly exhibits characteristics of a dense granular flow,with the Savage number exhibiting a decreasing trend as the volume of mass *** process of particle breakage gradually occurs in a bottom-up manner,leading to a significant increase in the angular velocities of the rock blocks with increasing *** simulation results reproduce the field observations of inverse grading and source stratigraphy preservation in the *** propose a disintegration index that incorporates factors such as drop height,rock mass volume,and rock *** findings demonstrate a consistent linear relationship between this index and the fragmentation degree in all tested scenarios.

关键词： Rock fragmentation Rockslide Numerical modelling Discrete-continuous modelling Runout Cohesive zone model

Improving Gravity Anomalies Over China Marginal Sea from Retracked Geosat and ERS-1 Data

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Geo-Spatial Information Science 2010年第2期13卷 144-149页

作者： WANG Haihong yang yuande HWANG Chenway CHU Yonghai MA Xinying School of Geodesy and Geomatics Wuhan University 129 Luoyu Road Wuhan 430079 China Key Laboratory of Surveying and Mapping Technology on Island and Reef State Bureau of Surveying and Mapping 579 Qiangangwan Road Qingdao 266510 China Department of Civil Engineering Chiaotung University Hsingchu 30050 China Geodetic Data Processing Center State Bureau of Suneying and Mapping 334 East Youyi Road Xi'an 710054 China

The quality of altimeter data and ocean tide model is critical to the recovery of coastal gravity anomalies. In this contribution, three retracking methods (threshold, improved threshold and Beta-5) are investigated with the aim of improving the altimeter data over a shallow water area. Comparison indicates that the improved threshold is the best retracking method over China Sea. Two ocean tide models, NAO99b and CSR4.0, are analyzed. Results show that different tide models used in the processing of altimeter data may result in differences more than 10 mGal in recovered coastal gravity anomalies. Also, NAO99b is more suitable than CSR4.0 over the shallow water area of China Sea. Finally, gravity anomalies over China Sea are calculated from retracked Geosat/GM and ERS-1/GM data by least squares collocation. Comparison with shipborne gravimetry data demonstrates that gravity anomalies from retracked data are significantly superior to those from non-retracked data. Our results have the same order as the other two altimeter-derived gravity models: Sandwell&Smith(V16) and DNSC08.

关键词：卫星测高法波形重新追踪严肃异例潮模型中国边缘的海

Sea ice concentration over the Antarctic Ocean from satellite pulse altimetry

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Science China Earth Sciences 2011年第1期54卷 113-118页

作者： yang yuande E DongChen WANG ,HaiHong CHAO DingBo HWANG CheinWay LI Fei AI SongTao Chinese Antarctic Center of Surveying and Mapping Wuhan University Wuhan 430079 China School of Geodesy and Geomatics Wuhan University Wuhan 430079 China Key Laboratory of Surveying and Mapping Technology on Island and Reef State Bureau of Surveying and Mapping Qingdao 266510 China Department of Civil Engineering 'National' Chiao Tung University Hsinchu Taiwan China

Sea ice concentration (SIC) is an important parameter in characterizing sea ice. Limited by the environment and the spatial extent of observation, it is difficult for field work to meet the needs of a large-scale SIC study. However, with its many advantages, such as the ability to make large-scale, high-resolution and long-duration observations, the altimeter can be used to determine SIC on a large scale. Using the correspondence between the satellite pulse altimeter waveform and reflector property, waveform classification is employed. Moreover, this paper develops an algorithm to obtain the SIC from altimeter waveforms. In an actual computation, Pyrz Bay in the Antarctic is taken as an experimental region, and one-year and seasonal SICs are derived from ERS-1/GM waveforms over this study area. Furthermore, altimetric SICs are compared with those of SSMR SSM/I. The results show that the spatial distribution and the regions of maximum SIC determined employing these two methods are consistent. This demonstrates that altimeter data can be used to monitor sea ice.

关键词：卫星测高海冰浓度脉冲南极海域波形分类碳化硅

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南极威德尔海沉积盆地重力异常特征

地球物理学报 2022年第5期65卷 1732-1741页

作者：周磊杨元德郝卫峰李斐晏鹏武汉大学中国南极测绘研究中心武汉430079 湖北师范大学文理学院理工学部湖北黄石435002

本文将卫星重力数据与威德尔海船测重力数据进行对比验证,利用Parker方法获取威德尔海沉积盆地布格重力异常;在此基础上建立沉积盆地模型,计算莫霍面补偿效应和沉积过程的重力效应比值,探索威德尔海沉积盆地重力异常与波长之间的联系;采... 详细信息

本文将卫星重力数据与威德尔海船测重力数据进行对比验证,利用Parker方法获取威德尔海沉积盆地布格重力异常;在此基础上建立沉积盆地模型,计算莫霍面补偿效应和沉积过程的重力效应比值,探索威德尔海沉积盆地重力异常与波长之间的联系;采用Airy-Hesikanen均衡模型计算均衡异常,探讨海陆边界的均衡状态.结果表明:(1)威德尔海沉积盆地布格重力异常值随波长变化呈现不同特征:波长为200~600 km(对应沉积盆地宽度为100~300 km)的布格重力异常主要呈现正值,而波长为80~200 km(对应沉积盆地宽度为40~100 km)的布格重力异常主要为负异常.(2)基于沉积盆地模型分析表明,威德尔海沉积盆地重力异常正值可能并不是由地壳长期底侵作用形成,而是沉积作用与裂隙作用共同导致的结果.(3)威德尔海沉积盆地边界的均衡重力异常表现为高负值,反映了威德尔海盆地沉积过程与冰架排挤系统有关.

关键词： Parker方法布格重力异常沉积盆地威德尔海

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南极冰川地震学研究进展

地球物理学进展 2022年第5期37卷 1875-1884页

作者：俞慧婷陈宇乔杨元德李斐武汉大学中国南极测绘研究中心武汉430079

冰川地震学是冰川学与地震学的交叉学科,其核心内容是运用地震学方法开展冰震、冰川结构及变化等研究.南极冰川类型丰富,拥有大量快速冰流以及大型冰架,其冰盖内部及边缘地区拥有丰富的冰震来源,各类冰震发震频繁,冰震信号频带宽、震级... 详细信息

冰川地震学是冰川学与地震学的交叉学科,其核心内容是运用地震学方法开展冰震、冰川结构及变化等研究.南极冰川类型丰富,拥有大量快速冰流以及大型冰架,其冰盖内部及边缘地区拥有丰富的冰震来源,各类冰震发震频繁,冰震信号频带宽、震级跨度大,在全球冰冻圈中具有代表性.南极冰川结构变化与物质平衡密切相关,冰川地震学研究可以通过监测各类冰川结构变化事件,为南极内部结构变化带来新的认识.本文首先介绍了南极地区冰川地震学研究开展情况,总结出5类具有代表性的南极冰震,并结合南极部分冰流、溢出冰川、冰架以及冰山详细描述其类型及特征.其次,对Rutford冰流、Whillans冰流、Ross冰架以及Thwaites冰川4个典型区域的冰川地震学研究情况进行介绍.最后,针对在南极开展冰川地震学研究面临的机遇和挑战,进行了探讨.

关键词：南极冰震冰川地震学南极冰川

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卫星测高波形重跟踪算法在南极应用的比较

大地测量与地球动力学 2007年第1期27卷 45-49页

作者：鄂栋臣杨元德武汉大学中国南极测绘研究中心

在阈值法的基础上提出了一种新的波形重跟踪算法——改进阈值法;采用Envisat数据计算,从数据利用率及距离改正标准差两方面,根据波形宽度分区对阈值法、OCOG以及Beta-5等3种算法作了比较,证实了改进阈值法在南极区域更为有效。

关键词：卫星测高南极 Envisat 波形重跟踪改进阈值法

Surface Mass Balance over Dome Argus, East Antarctica

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Surface Mass Balance over Dome Argus, East Antarctica