长江三峡大宁河流域3000年来的环境演变与人类活动   总被引：7，自引：6，他引：7  

张芸  朱诚  于世永 《地理科学》2001,21(3):267-271

长江三峡大宁河流域张家湾东周-汉代古遗址的孢粉学和沉积学等分析结果表明3000年来该区环境演变与人类活动的互动影响，连续的孢粉和粒度记录证实，该区古人类活动初期处于暖湿的气候，东周-汉代时期转变为温凉略干的温带气候，东周-汉代后，该区经历了一次规模较大的大宁河洪水泛滥期，导致汉代文化层中断。此后不久，由于人类活动剧烈，自然植被严重破坏，水土流失比较严重，山洪灾害频繁，导致汉代之后该区没有连续的文化层堆积，而由于人类活动剧烈，自然植被严重破坏，水土流失比较严重，山洪灾害频繁，导致汉代之后该区没有连续的文化层堆积，而由于短暂洪水暴发引起大面积坡面片流，导致坡积物的大量堆积，汉代之后该区频繁的兴涝灾害和山洪灾害体现了人地关系的复杂性。  相似文献   

中国高放废物处置库选址中灵敏地质特征的初步确认   总被引：5，自引：0，他引：5  

陈伟明  王驹  若杉圭一郎 《铀矿地质》2001,17(2):65-69,96

本文首先根据中国、瑞士和日本3国高放废物处置概念的相似性，建立中国第一处置库系统性能评价模型；然后通过对9个地质变量在8个事件中的灵敏度分析，初步确认出3个灵敏地质物征。此项研究对中国目前高放废物处置库选址工作有一定的指导意义。  相似文献   

芜湖市航运局综合楼地基处理失误诱发地面塌陷的治理     

孙凤贤 《安徽地质》2001,11(3):230-234

论述航运局综合楼地基所在处的地形地貌、水文地质、工程地质条件；分析地基基础盲目施工诱发造成建筑场地工程地质灾害和危及周国民居安全的原因，提出防治措施，合理施工，治理塌陷，并取得较好效益。  相似文献   

Investigation of a landslide in the new site of Badong County by integrated geophysical survey     

LIU Song  ZHANG Shuangxi  Li Jiangfeng 《中国科学D辑(英文版)》2001,44(5):426-436

An integrated geophysical survey which combines vertical seismic profile method, shallow reflection seismic method, electric sounding, soil temperature measurement and radioactive gas measurement was used to investigate Zhaoshuling landslide in the new site of Badong County and to assess the stability of the landslide. By rational use of these methods together with borehole geological profile and other geological information, the spatial distribution of the landslide body, the formations and structures within and without the landslide body were determined and the stability of the landslide was also assessed, thus making great contribution to the successful and rational investigation and assessment of the landslide.  相似文献   

GRASS数据结构分析     

夏伟玲 《测绘信息与工程》1996,(3)

详细分析了ＧＲＡＳＳ的三种数据结构，为设计ＧＲＡＳＳ与其它系统数据格式转换接口提供了基础。  相似文献   

建设中国遥感卫星辐射校正场的构想     

张广顺  张玉香 《气象》1996,22(9):15-18

该文论述了中国遥感卫星辐射校正场筹建的必要性，辐射校正的基本原理和我国的辐射校正场建设的构想。  相似文献   

The effect of low-velocity sediments on the mislocation vectors of the GRF array   总被引：1，自引：0，他引：1  

F. Krüger  M. Weber 《Geophysical Journal International》1992,108(1):387-393

  相似文献   

Mineralogical and geochemical behavior of mill tailing material produced from lead-zinc skarn mineralization,Hanover, Grant County,New Mexico,USA   总被引：3，自引：0，他引：3  

I. F. Walder  W. X. Chavez Jr. 《Environmental Geology》1995,26(1):1-18

Mineral extraction and processing, especially metal mining, produces crushed and milled waste; such material, exposed to weathering, poses the potential threat of environmental contamination. In this study, mill tailings from inactive Pb-Zn mines in New Mexico, southwest USA, have been examined for their potential environmental impacts by means of detailed mineralogical and geochemical characterization. The principal ore minerals remaining in the tailings material are sphalerite, chalcopyrite, and very minor galena, smithsonite, and cerrusite, accompanied by the gangue minerals pyrite, pyrrhotite, magnetite, hematite, garnet, pyroxene, quartz, and calcite. White precipitate occurring on tailings surfaces is composed of gypsum and hydrated magnesium sulfates. Pyrite is mostly unaltered or shows only micron-scale rims of oxidation (goethite/hematite) in some surface samples. This iron oxide rim on pyrite is the only indication of weathering-derived minerals found by microscopy. There are variations in element concentrations with depth that reflect primary variations through time as the tailings ponds were filled. Cadmium and Zn concentrations increase with depth and Ag and Pb are low for the uppermost core samples, while Cu, Ni, and Co concentrations are generally high for the uppermost core samples. These elemental distributions indicate that little or no leaching has taken place since emplacement of the tailings because no accumulation or enrichment of these metals is observed in Hanover tailings, even in reducing portions of tailings piles. Element concentrations of surface samples surrounding the tailings reflect underlying mineralized zones rather than tailings-derived soil contamination. We observed no successive decreasing metal concentrations in prevalent wind directions away from the tailings. Stream sediment samples from Hanover Creek have somewhat elevated Zn, Cd, and Pb concentrations in areas that receive sediments from erosion of the tailings. However, input from tributaries downstream of the ponds appears to be principal source of heavy metals in Hanover Creek. The results of this study indicate that there is low risk for groundwater heavy-metal contamination from Hanover tailings. Tailings material do not show significant geochemical oxidation/alteration or metal leaching with depth. Our studies indicate that neutralizing minerals present in the tailings are sufficient to keep the tailings material chemically stable. Geochemically, however, tailings materials are being eroded and may pose a threat to Hanover Creek via siltation.  相似文献   

在某污染的工业废物填埋场环境水文 地质评价中的同位素水文学研究     

王志明  肖丰  邓金贵  李森 《铀矿地质》1993,(6)

本文论述了某污染的工业废物填埋场场址的地质、水文地质条件,应用水化学方法、环境同位素技术(地下水中氚及氢、氧稳定同位素)和同位素单孔示踪技术等同位素水文学领域中的新方法对区内地下水的活动条件以及填埋场场址区分布的第四系孔隙潜水和第三纪红层孔隙-裂隙水的成因进行了分析,测量并确定了填埋场下部地下水的流速及流向。研究结果表明场区地下水的运动与地表水无直接水力联系。污染的工业废物填埋后不会通过地下水的迁移造成对地表水的污染,进而证实填埋场的地质、水文地质条件对处置污染的工业废物是安全可靠的。  相似文献   

Effects of Deicing-Salts on Heavy Metal Mobility Zum Einfluß von Streusalzen auf die Beweglichkeit von Schwermetallen     

B. Bauske  D. Goetz 《洁净——土壤、空气、水》1993,21(1):38-42

Heavy metal input into roadside soils and effects of deicing salts are often discussed as separate environmental problems. However, a relationship between salt input and heavy metal mobility has already been detected in laboratory tests. During a 2-year field study, the soil solution of a roadside soil was continuously sampled. The results of soil solution analysis not only showed a strong rise in deicing-salt related sodium, calcium and chloride concentrations, but also high zinc and cadmium values in winter and spring. Additional laboratory tests confirmed the mobilizing effects of salt solution which contained NaCl and CaCl₂. Cation exchange and the formation of chlorocomplexes are discussed as the responsible mechanisms.  相似文献