低轨道人造卫星(CHAMP、GRACE、GOCE)与高精度地球重力场——卫星重力大地测量的最新发展及其对地球科学的重大影响   总被引：33，自引：26，他引：7  

孙文科 《大地测量与地球动力学》2002,22(1):92-100

评述了卫星重力大地测量的最新发展及其对地球科学的重大影响。为了更好地理解地球内部物理构造与海洋动力学，以及大陆，冰川和海洋的相互作用，改善现有地球重力场模型（包括精度和空间解析度）是非常重要的。IUGG等国际组织对此已经强调了很多年。最近，由德国的GFZ（GeoForschungsZentrum)，美国的NASA（National Aeronautics and Space Adminitration)以及欧洲宇航局ESA（European Space Agency)开发研制了最先进的地球监测技术－SST（Satellite-to-Sateilite Tracking)。其主要特点是利用现有的GPS连续追踪新发射低轨道卫星，并由低轨道卫星对地球重力场作精密观测。已经发射和即将发射的卫星有3颗：GHAMP（Challenging Mini-Satellite Payload for Geophysical Research an Application)已经于2000年发射；GRACE（Gravity Recovery and Climate Experimert)定于2002年发射；GOCE（Gravity Field and Steady-state Ocean Cirulation Explorer)计划2004年发射，它们可以统称为重力卫星。载有SST技术的人造卫星的主要目的是获得具有前所未有的高精度和高空间解析度的全球重力场和大地水准面模型，加强人们对地球内部构造的理解并为海洋和气象研究提供更好地参考。上述3个重力卫星工作在有明显区别的不同波谱内，它们有不同的科学应用，仅有一小部分重合。所以，就应用而言它们是完全互补的。它们在地球科学中的应用将是广泛的，特别对于固体地球物理学，海洋学以及大地测量学等领域，它们将会带来革命性的变化，其意义不亚于GPS。  相似文献   

THE POSITION AND ROLES OF PORTS AND RAILWAYS IN THE EURASIA LAND BRIDGE TRANSPORTATION IN NORTHEAST CHINA     

叶宝明  李文杰 《中国地理科学(英文版)》1992,2(3):235-244

This paper systematically analyzes and proves the favorable factors of utilizing the ports and the railways in Northeast China for the Asia-Europe land bridge transportation. It will be more beneficial to Dalian Port and HaDa (Harbin-Dalian) and Binzhou (Harbin-Manzhouli) railways in Northeast China to the Siberia railway in Russia than 1) to other ports and the corresponding railways in China, 2) to the Nakhodka Port in Russia and the corresponding railways and 3) to the Chongjin Port in North Korea and the corresponding railways. This paper also puts forward the reform measures to adopt the ports and the railways in the northeast region in China for the land bridge transportation and the problems in transportation policies and management systems.  相似文献   

莱州湾南岸潍河下游地区咸水入侵灾害成因及特征   总被引：8，自引：1，他引：7  

刘恩峰  张祖陆  沈吉  宋俊峰 《地球科学与环境学报》2004,26(3):78-82,87

通过对莱州湾南岸咸水入侵较严重地潍河下游地区晚更新世以来沉积特征及现代自然环境条件变化的分析，探讨了沉积相对咸水入侵产生及空间范围特征的环境机理。晚更新世以来的三次海平面升降变化造成了潍河下游地区海陆沉积环境交替，形成了巨厚的海陆交互相沉积层。海进时期，大面积的滨海平原被淹没，在近海平原洼地滞留的海水经过蒸发、浓缩变为卤水，成为咸水入侵的物源；海退后陆源碎屑在滨海地区沉积形成了巨厚的古河道砂层。20世纪70年代末期以来，随着对地下淡水的过度开采，淡咸水水头压力差减小．卤水通过古河道砂层快速南侵。通过对潍河下游地区100余个地质钻孔水化学连续监测资料分析，阐明了咸水入侵的特征，有针对性地提出了咸水入侵的防治措施。  相似文献   

Revisiting Sustainable Development of Dry Valleys in Hengduan Mountains Region   总被引：5，自引：1，他引：4  

TANGYa XIEJiasui SUNHui 《山地科学学报》2004,1(1):38-45

Dry valleys are a striking geographic landscape in Hengduan Mountains Region and are characterized by low rainfall, desert type of vegetation and fragile environment. Past efforts and resources have been concentrated mainly on rehabilitation of degraded ecosystem and fragile environment, particularly reforestation, while socio-economic development has been largely overlooked. Despite successes in pocket areas, the overall trend of unsustainability and environmental deterioration are continuing. It is important to understand that uplift of the Tibetan Plateau is the root cause of development of dry valleys, and development and formation of dry valleys is a natural process. Human intervention has played a secondary role in development of dry valleys and degradation of dry valleys though human intervention in many cases has speeded up environmental degradation of the dry valleys. It is important to understand that dry valleys are climatic enclaves and an integrated approach that combines rehabilitation of degraded ecosystems and socio-economic development should be adopted if the overall goal of sustainable development of dry valleys is to be achieved. Promotion of niche-based cash crops, rural energy including hydropower, solar energy, biogas and fuelwood plantation is recommended as the priority activities.  相似文献   

沂水崔家峪玻璃用石英砂岩矿地质特征          下载免费PDF全文

李祥忠  程晓萍  杨学生  解庆岭 《山东国土资源》2004,20(2):34-40

沂水崔家峪玻璃用石英砂岩矿床赋存于早寒武世李官组砂岩段中．呈近水平的层状产出。因其岩石坚硬．矿体呈环山的平台状分布。矿体厚度大，矿石品级高，特级品矿石二氧化硅平均含量98．47％，铁杂质平均含量0．043％(选矿后，铁杂质含量可降至0．02％以下)，为一优质玻璃硅质原料矿床。矿石为细一中粒石英砂岩，粒度以中粒为主，矿石由碎屑颗粒和胶结物组成，碎屑成分含量为97％～98％．其中绝大部分是石英颗粒．具典型的砂屑结掏。该矿床属滨海陆源沉积矿床。  相似文献   

济宁市嘉祥县石灰岩矿山地质环境评价与治理   总被引：1，自引：0，他引：1       下载免费PDF全文

贾德旺  吕宝平  贺汉庭  王学森  范纯信 《山东国土资源》2006,22(5):54-57

在对嘉祥县石灰岩矿进行地质灾害危险性评估、矿山环境地质问题评价的基础上,建立了一套评价体系,其中地质灾害危险性评估分为2个评价指标,矿山环境地质问题评价分为2种要素3个指标,同时将矿山恢复治理难易程度也作为一个评价因子。评价过程中对各指标危害性大、中、小程度均单独赋值,然后将各指标的分值进行叠加,确定出矿山环境地质问题的等级,将概划出的13个评价单元分为极差、差、一般3个区。提出了强化矿山管理、植树造林、科学避让、修建拦水坝等保护与治理措施及建议。  相似文献   

Precipitation patterns in flood season over China associated with the El Niño/Southern Osciliation     

Budong Qian 《中国地理科学(英文版)》1997,7(3):220-228

The precipitation patterns in flood season over China associated with the El Niño/Southern Oscillation (ENSO) are investigated, especially in the eastern China, using the rather long period rainfall data in this century. The results show that there were remarkable differences between the precipitation patterns in flood seasons of ENSO warm phase (El Niño year) and cold phase (La Niña year), as well as between the patterns in El Niño years and their following years. The most parts of China received below normal rainfall in flood season of the onset years of El Niño events, but the coastal area of Southeast China received above normal amounts. Comparatively, the most parts of China received above normal rainfall in flood season of the following years of El Niño events, but the eastern part of the reaches among the Huanghe (Yellow) River, the Huaihe River and the Haihe River, and the Northeast China received less. During ENSO cold phase, the reaches of the Changjiang (Yangtze) River and the North China received more amounts than normal rainfall in flood season of the onset years of La Niña events, and the other regions of China received less. In the following years of La Niña events, the coastal area of the Southeast China, the most part of the Northeast China and the regions between the Huanghe River and the Huaihe River received more precipitation during flood seasons, but the other parts received below normal precipitation.  相似文献   

Porphyroblast inclusion-trail orientation data: eppure non son girate*!     

T. H. BELL  S. E. JOHNSON  B. DAVIS  A. FORDE  N. HAYWARD  C. WILKINS 《Journal of Metamorphic Geology》1992,10(3):295-307

Extensive examination of large numbers of spatially orientated thin sections of orientated samples from orogens of all ages around the world has demonstrated that porphyroblasts do not rotate relative to geographical coordinates during highly non-coaxial ductile deformation of the matrix subsequent to their growth. This has been demonstrated for all tectonic environments so far investigated. The work also has provided new insights and data on metamorphic, structural and tectonic processes including: (1) the intimate control of deformation partitioning on metamorphic reactions; (2) solutions to the lack of correlation between lineations that indicate the direction of movement within thrusts and shear zones, and relative plate motion; and (3) a possible technique for determining the direction of relative plate motion that caused orogenesis in ancient orogens.  相似文献   

山区公路软基病害研究   总被引：2，自引：0，他引：2  

刘雪岭  苏生瑞  周新民 《地球科学与环境学报》2005,27(1):65-69

随着高等级公路建设规模的扩大，山区公路所面临的路基病害特别是软土路基病害问题也逐渐增多。结合对陕南勉(县)一宁(强)高速公路工程实例分析，对山区软土成因及其特性进行了初步分析，认为山区软土属以坡洪积、湖积和冲积为主的软土，也有少量是由坡残积物堆积而形成。山区软土的特殊性表现在成分的复杂性、分布的不均匀性、隐蔽性和物理力学性质的特殊性。根据其特性以及中国山区公路软基普遍存在的病害问题，总结了山区公路软基的主要病害类型为剪切拉裂破坏、浸水沉陷破坏、剥蚀坍塌破坏、推挤滑动破坏。还提出了相应的软基处理方法及建议。  相似文献   

THE CORPORATE INTERVIEW AS A RESEARCH METHOD IN ECONOMIC GEOGRAPHY*     

Erica Schoenberger 《The Professional geographer》1991,43(2):180-189

The open-ended corporate interview as a qualitative research method is proposed as a valuable component of an evidentiary strategy in economic geography. It is argued to be more sensitive than other survey methods to historical, institutional, and strategic complexity. The corporate interview method is particularly appropriate in periods of economic and social change that challenge traditional analytical categories and theoretical principles. Some problems inherent to the method, and strategies for minimizing their impact on the research project, are described.  相似文献