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Sun Yat-sen and Yangtze River Development:A Review on the General Plan of National Construction
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作者 Pi Mingxiu Li Caige 《China City Planning Review》 CSCD 2017年第1期73-78,共6页
General Plan of National Construction Author:Sun Yat-sen Year:2014 Publisher:SDX Joint Publishing Company ISBN:9787108040749(486 pages,in Chinese)In the studies on Sun Yat-sen,~①it is very natural that the focus has ... General Plan of National Construction Author:Sun Yat-sen Year:2014 Publisher:SDX Joint Publishing Company ISBN:9787108040749(486 pages,in Chinese)In the studies on Sun Yat-sen,~①it is very natural that the focus has always been put on Sun Yat-sen’s revolutionary thoughts 展开更多
关键词 Sun Yat-sen and Yangtze river development:A Review on the General Plan of National Construction
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Evaluation of Coordinated Development of Urbanization and Ecological Environment in the Efficient Ecological Economic Zone of the Yellow River Delta
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作者 Gu Ruili Wang Linlin 《Meteorological and Environmental Research》 CAS 2018年第3期47-51,共5页
Based on the statistical data of urbanization development level and ecological environment in the Yellow River Delta during 2009-2014,a comprehensive index system for the coordinated development of urbanization and ec... Based on the statistical data of urbanization development level and ecological environment in the Yellow River Delta during 2009-2014,a comprehensive index system for the coordinated development of urbanization and ecological environment was established to evaluate the coordinated development level. The results showed that the coordinated development level of urbanization and ecological environment in the Yellow River Delta was generally high during 2009-2014. The development level of urbanization was higher than that of ecological environment on the whole,that is,the development of ecological environment lagged behind. The development of urbanization in the region was relatively slow during 2009-2011 but rapid during 2012-2014. The development level of ecological environment was relatively stable and always increased. 展开更多
关键词 Urbanization Ecological environment COORDINATED development The Yellow river Delta
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Landslide Developmental Characteristics and Response to Climate Change since the Last Glacial in the Upper Reaches of the Yellow River, NE Tibetan Plateau 被引量:18
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作者 YIN Zhiqiang QIN Xiaoguang +2 位作者 YIN Yueping ZHAO Wuji WEI Gang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第2期635-646,共12页
The upper reaches of the Yellow River in northeastern Tibetan Plateau are geohazards areas.The evolution of the Yellow River,chronology of some landslides,and spatiotemporal distribution characteristics of super large... The upper reaches of the Yellow River in northeastern Tibetan Plateau are geohazards areas.The evolution of the Yellow River,chronology of some landslides,and spatiotemporal distribution characteristics of super large scale and giant landslides within the region are summarized using paleoclimate evidence,and the relationship between the intensive landslide period and climatic changes since the Last Glacial period is analyzed.It is concluded that (1) Super large scale and giant landslides are distributed widely within the region,particularly in the Qunke-Jianzha basin.(2) The chronological sequence of landslides is established by dating the slip zones of landslides and analyzing the relations between landslides and their overlying or underlying loess formations.Five landslide development periods are determined:53-49 ka BP,33-24 ka BP,10-8 ka BP,5-3.5 ka BP,and the present.(3) These correspond closely to warm and wet periods during the last 100,000 years,i.e.,two weak paleosol development stages of Malan loess deposited during the last Glacial period in the Chinese loess Plateau,L1-4 and L1-2 that belong to the marine oxygen isotope stage 3,the last deglaeial period,the Holocene Optimum,and the modern global warming period.(4) Landslide triggers may be closely linked to warm and wet periods related to rapid climatic transitions. 展开更多
关键词 LANDSLIDE developmental characteristics climate change upper reaches of the Yellow river response
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Building the Three Gorges Project for the Chinese Nation—An Interview with General Manager Lu Youmei, China Yangtze River Three Gorges Project Development Corporation
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《China's Foreign Trade》 1994年第2期25-25,共1页
The Yangtze River has nurtured the fertile land on both its banks and hundreds of millions of Chinese people. but its raging waters have also wreaked havoc on the people living in its reaches. Since the founding of Ne... The Yangtze River has nurtured the fertile land on both its banks and hundreds of millions of Chinese people. but its raging waters have also wreaked havoc on the people living in its reaches. Since the founding of New China, large-scale surveys, planning, scientific research and feasibility studies have been carried out in an effort to harness the 展开更多
关键词 Project China Yangtze river Three Gorges Project development Corporation An Interview with General Manager Lu Youmei Building the Three Gorges Project for the Chinese Nation
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PORT DEVELOPMENT IN YANGTZE RIVER DELTA
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作者 Ren Mei-e(State Pilot Laboratory of Coast and Island Exploitation, Nanjing University, Nanjing)CAS Member 《Bulletin of the Chinese Academy of Sciences》 1996年第4期321-327,共7页
The Yangtze river delta has the largest port group in China.On the coast are sea ports,Yangkou Shanghai Beilun,aligned on a north-south axis which,together with ports along the Lower Yangtze river,form a T-shaped port... The Yangtze river delta has the largest port group in China.On the coast are sea ports,Yangkou Shanghai Beilun,aligned on a north-south axis which,together with ports along the Lower Yangtze river,form a T-shaped port association.This is unique in the country.For rational port localization and development,it is suggested that Shanghai should retain its undisputed position as an international and domestic hub port of China.Beilun and Yangkou,with their deep-water berths,should be transshipment ports of imported bulky goods (ore,crude oiletc.) and inter-continental international containers for Shanghai and the Yangtze valley above Nanjing,while ports on the lower Yangtze river will 展开更多
关键词 PORT development IN YANGTZE river DELTA DEEP TEU
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Water sustainable development in the Shiyang river basin of northwest China
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《Global Geology》 1998年第1期1-1,共1页
关键词 Water sustainable development in the Shiyang river basin of northwest China
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Rural Domestic Sewage Treatment Model: Case Study Based on Dongying Section of the Yellow River Basin
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作者 Shan Zhang Yu Wang Xiujuan Wang 《Journal of Environmental Protection》 CAS 2023年第3期172-184,共13页
The 20<sup>th</sup> National Congress of the Communist Party of China proposed to promote the improvement of urban and rural living environment and build livable and workable villages and beautiful village... The 20<sup>th</sup> National Congress of the Communist Party of China proposed to promote the improvement of urban and rural living environment and build livable and workable villages and beautiful villages. The development and challenges of rural domestic sewage treatment coexist. Based on the field investigation of 15 administrative villages in 3 districts and counties of Dongying City, there is a big gap between the development status of rural domestic sewage treatment and expectations. Investigate rural domestic sewage treatment cases in-depth, and condense four modes of primitive, developmental, mature and advanced in a variety of different rural domestic sewage treatment models for discussion, among which, the village sewage treatment work under the mature mode has achieved remarkable results, and is at the forefront of the current rural domestic sewage treatment. Through the multi-case analysis method, the practical dilemma of sewage treatment in different models of villages is summarized, and the feasible improvement path is explored, which contributes to the ecological protection and high-quality development of Dongying and the Yellow River Basin. 展开更多
关键词 Rural Domestic Sewage Human Settlements Ecological Protection and High-Quality development of the Yellow river Basin
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广西恭城县河谷阶地地貌区岩溶塌陷地质灾害发育特征及形成机理
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作者 覃莹璐 丁凯 +1 位作者 程亚平 范新东 《地下水》 2024年第3期149-152,共4页
河谷阶地地貌区是广西恭城县岩溶塌陷灾害高发区。本次研究以《恭城瑶族自治县1:5万地质灾害详细调查》项目为依托,综合地形地貌、地质构造、地层岩性、气象条件,分析恭城县河谷阶地地貌区岩溶塌陷的分布规律、影响因素及发育特征,并综... 河谷阶地地貌区是广西恭城县岩溶塌陷灾害高发区。本次研究以《恭城瑶族自治县1:5万地质灾害详细调查》项目为依托,综合地形地貌、地质构造、地层岩性、气象条件,分析恭城县河谷阶地地貌区岩溶塌陷的分布规律、影响因素及发育特征,并综合恭城县栗木镇竹凤村某处的塌陷实例,探究河谷阶地地貌区岩溶塌陷成因。研究表明:(1)河谷阶地内42处塌陷均为土洞型塌陷,塌陷坑坑口形状主要有不规则形、圆形两种,个别坑口为方形,坑口长轴方向大致与地下水的流向一致。(2)岩溶塌陷发育诱发因素以自然因素为主,人为因素为辅。从行政区域上看,塌陷发育数量最多的城镇为栗木镇,共有9处塌陷灾害点,占岩溶塌陷灾害总数的22.70%;从规模上看,研究区已发生的岩溶塌陷以小型塌陷为主,只有1处塌陷体积规模大于500 m^(3),规模为100~500 m^(3)的岩溶塌陷有11处,规模为50~100 m^(3)的岩溶塌陷有4处,小于50 m^(3)的塌陷有26处。(3)地形地貌是岩溶塌陷灾害形成的主控因素之一。岩溶塌陷发育受覆盖土层厚度影响,覆盖土层越薄,土洞顶板越薄,越容易发生地面塌陷。其主要分布在D 2t、C 1yt地层中,集中发育于覆盖土层厚度为5~15 m的区域;降雨是诱发区内岩溶塌陷发育的因素之一,但不是决定性因素。研究结果以期为同类地区岩溶塌陷预防和治理提供参考依据。 展开更多
关键词 河谷阶地 岩溶塌陷 发育特征 地质灾害
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珠江三角洲西北部晚第四纪沉积演化研究
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作者 史秋艾 《中国煤炭地质》 2024年第7期25-28,共4页
通过对珠江三角洲西北部的地层、沉积演化过程开展深入研究,结果显示研究区发育有河流相、滨海相、浅海相和河海混杂相等沉积相;晚更新世时期沉积厚度变化较大,地层垂向相变相似;全新世时期,整体沉积厚度相差不大,受沉积环境和地形地貌... 通过对珠江三角洲西北部的地层、沉积演化过程开展深入研究,结果显示研究区发育有河流相、滨海相、浅海相和河海混杂相等沉积相;晚更新世时期沉积厚度变化较大,地层垂向相变相似;全新世时期,整体沉积厚度相差不大,受沉积环境和地形地貌影响,地层垂向沉积表现出同期异相性分布。晚第四纪以来,研究区沉积历史海陆交互相相变频繁,形成了复杂多样的三角洲沉积物。 展开更多
关键词 珠江三角洲 晚第四纪 发育特征 沉积演化
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The coordination of regional interest in developing river basin
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作者 Chen Xiangman 《Ecological Economy》 2006年第1期47-54,共8页
River basin is a special region with the characteristics of entireO, and relation, regionality and dlversity, gradation and network, openness and dissipation etc. It is an important unit that organizes and governs nat... River basin is a special region with the characteristics of entireO, and relation, regionality and dlversity, gradation and network, openness and dissipation etc. It is an important unit that organizes and governs national economy as well as a natural re, on. In river basin, all natural essential factors relate closely each other, and there is remarkable influence between inter-regions. In the process of developing river basin, the multiplex main interest body, the diverse interest demand and the multi-ways of interest realization constitute a complicated interest network, and result in various contradictions and conflicts. Therefore, egective regional interest coordination mechanism should be estabfished to coordinate various regional interest relations. They are the public interest realization mechanism, the fair interest assignment mechanism, the effective interest integration mechanism, the expedited interest expression mechanism and the reasonable interest compensative mechanism. 展开更多
关键词 river basin development and management Regional interested Regional interest coordination mechanism
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Experimental Analysis on Allometric Growth in Spualiobarbus curriculus Larvae and Juveniles in Zhaoqing Reach of the Pearl River
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作者 Chen Fangcan Li Xinhui +5 位作者 Li Jie Li Yuefei Shuai Fangmin Yang Jiping Wu Zhi Zhu Shuli 《Animal Husbandry and Feed Science》 CAS 2018年第1期1-6,71,共7页
Ecological experiment was conducted in this paper to study the allometric growth in Squaliobarbus curriculus larvae and juveniles from Zhaoqing Reach of the Pearl River. The results showed that after first feeding, th... Ecological experiment was conducted in this paper to study the allometric growth in Squaliobarbus curriculus larvae and juveniles from Zhaoqing Reach of the Pearl River. The results showed that after first feeding, the organs associated to swimming, feeling and feeding of larvae differentiated rapidly, and exhibited allometric growth. The head length, tail length and head height exhibited positive allometric growth, while trunk length exhibited negative allometric growth before reaching the growth inflexion point 20 d after first feeding, and positive allometric growth after the inflection point. Body height exhibited positive allometric growth both before and after the growth inflexion point at 18 d after first feeding. The inflexion points of snout length, eye diameter and post-eye head length occurred 23, 19 and 16 d after first feeding. For swimming organs, the dorsal fin, pelvic fins and anal fin exhibited positive allometric growth both before and after the inflexion point at 18, 19 and 17 d after first feeding; but the tail fin exhibited positive allometric growth before the inflexion point at 14 d after first feeding, and negative allometric growth after the inflexion point. S. curriculus larvae can possess various abilities soon after first feeding to survive at early stage due to the rapid development of swimming, feeling, feeding and other organs, which has important ecological significance to adapt to the complex external environment. 展开更多
关键词 Pearl river Squaliobarbus curriculus Larvae development pattern Allometric growth
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Mathematical Statistics and Spatial Aggregation Characteristics Analysis of Culture, Sports, and Tourism Resources in the Yellow River Basin Based on POI Data
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作者 Ruixiang Liu Xiaofeng Shi 《Open Journal of Applied Sciences》 2022年第5期688-713,共26页
As a priority of China’s regional development strategy in recent years, promoting the ecological protection and high-quality development of the Yellow River Basin is one of the important tasks to boost the country’s... As a priority of China’s regional development strategy in recent years, promoting the ecological protection and high-quality development of the Yellow River Basin is one of the important tasks to boost the country’s economy and also the key to the development strategy in the central region at this stage. High-quality development of the Yellow River Basin based on the perspective of culture, sports, and tourism integration is significant for the regional ecological protection and economic revitalization. In order to measure the development of culture, sports, and tourism resources in the basin, the study applied the CRITIC model in Mathematical Statistics, the fuzzy comprehensive evaluation model, and the entropy weight TOPSIS analysis model. The results indicated that the development of the three resources in the basin varies from region to region, among which Shaanxi, Shandong, and Henan provinces have developed outstandingly while western provinces in China haven’t. In addition, this study identified the spatial geographic extent and analyzed the POI (points of interest) of culture, sports, tourism, and mixed resource based on the data analysis to explore the spatial distribution characteristics and trend of changes in the Yellow River Basin. The study also made suggestions for the development of culture, sports, and tourism resources in the basin from different perspectives based on the developed theoretical model, aiming to promote high-quality development of the area. 展开更多
关键词 Integration of Sports and Tourism Sports Tourism High-Quality development of the Yellow river Basin
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藏东红层地区断裂对泥石流物源的控制作用——以西藏贡觉县哇曲中游流域为例
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作者 高波 张佳佳 +2 位作者 陈龙 田尤 刘建康 《中国地质灾害与防治学报》 CSCD 2023年第5期20-31,共12页
哇曲为金沙江二级支流,位于藏东昌都红层地区贡觉县,流域中游为高山峡谷区,是县域内典型的降雨型泥石流集中发育区。该区泥石流在发育密度、规模、活动性等特征上均高于全县平均水平,且泥石流的发育表现出了与断裂的强烈相关性。基于现... 哇曲为金沙江二级支流,位于藏东昌都红层地区贡觉县,流域中游为高山峡谷区,是县域内典型的降雨型泥石流集中发育区。该区泥石流在发育密度、规模、活动性等特征上均高于全县平均水平,且泥石流的发育表现出了与断裂的强烈相关性。基于现场调查,结合无人机航空摄影对哇曲流域泥石流发育特征和主要影响因素进行了探讨分析,得到以下结论:(1)哇曲中游集中发育19条小—中型降雨型泥石流,发育密度0.84条/km,远高于全县0.009条/km^(2)的平均水平;左岸泥石流在发育密度、流域面积、主沟长度、堆积体积等特征上均高于(大于)右岸,左右岸泥石流呈明显差异分布。(2)哇曲中游右岸泥石流物源以风化碎屑类物源为主,呈全沟域分布;左岸泥石流以崩滑物源和风化碎屑为主,集中分区在沟谷中上游,总量较右岸大,其中断层破碎带内物源量占比大,成为左岸泥石流的主要物源。(3)断裂是影响哇曲中游泥石流集中发育且呈现差异分布的最主要因素,主要体现在对物源条件的控制上。(4)断裂以改变岩体结构、控制地层分布、改变微地貌和地下水条件等方式控制泥石流物源条件,导致两岸泥石流物源形成速率和物源量明显不同,成为泥石流差异分布的根本原因。 展开更多
关键词 断裂 降雨型泥石流 差异分布 发育特征 哇曲
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金沙江上游圭利滑坡发育特征及运动过程分析 被引量:2
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作者 徐璐 常鸣 +2 位作者 武彬彬 刘沛源 周超 《防灾减灾工程学报》 CSCD 北大核心 2023年第4期845-853,共9页
金沙江上游构造破碎、岩体结构复杂,区内大型-巨型滑坡发育,历史上发生过多次滑坡堵江事件。圭利滑坡位于西藏江达县金沙江西岸,滑坡变形严重,大小拉裂缝、垮塌几乎覆盖整个滑坡,变形程度有不断增加的趋势,失稳后将对金沙江下游造成巨... 金沙江上游构造破碎、岩体结构复杂,区内大型-巨型滑坡发育,历史上发生过多次滑坡堵江事件。圭利滑坡位于西藏江达县金沙江西岸,滑坡变形严重,大小拉裂缝、垮塌几乎覆盖整个滑坡,变形程度有不断增加的趋势,失稳后将对金沙江下游造成巨大威胁。在野外调查的基础上,通过对金沙江上游圭利滑坡发育特征的分析,选取Massflow数值计算模型对该滑坡失稳运动过程进行预测分析,获取了滑坡在不同时刻的堆积状态及运动速度。结果表明,滑坡整体运动时长约为40 s,最大滑动速度达到31 m/s,最大堆积厚度为51 m;前缘向两侧扩散的最大距离约为220 m,并全部堵塞金沙江;滑坡各区域的速度曲线反映出滑坡运动过程具有突发性、彻底性、整体性、流态性的特点。 展开更多
关键词 金沙江上游 圭利滑坡 Massflow 发育特征 运动过程
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区域卫生健康标准一体化建设现状与长三角的实践
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作者 刘富强 陆轶 +3 位作者 邵晶 胡晓晴 肖萍 范玉兰 《中国卫生资源》 CSCD 北大核心 2023年第6期653-657,共5页
以开展长三角区域卫生健康领域标准化研究为基础,调查和分析我国京津冀地区、粤港澳地区和长三角地区区域协同标准发展现状,标准化工作运行机制和管理模式。结合区域统一地方标准立项和研制实践,提出长三角区域卫生健康标准一体化机制... 以开展长三角区域卫生健康领域标准化研究为基础,调查和分析我国京津冀地区、粤港澳地区和长三角地区区域协同标准发展现状,标准化工作运行机制和管理模式。结合区域统一地方标准立项和研制实践,提出长三角区域卫生健康标准一体化机制建立的初步思考,为建立长三角区域卫生健康标准化合作模式、组织框架、工作任务等提供研究基础。 展开更多
关键词 卫生健康标准health standards 长三角一体化发展integrated development of the Yangtze river Delta 京津冀协同标准Beijing-Tianjin-Hebei Collaborative Standards 粤港澳湾区标准Guangdong-Hong Kong-Macao Bay Area Standards
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城市河道水质恢复技术及发展趋势 被引量:60
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作者 邹丛阳 张维佳 +1 位作者 李欣华 李大鹏 《环境科学与技术》 CAS CSCD 北大核心 2007年第8期99-102,共4页
在分析城市河道水体污染现状和污染源的基础上,介绍了物理、化学、生物生态等城市河道水质恢复技术,分析了不同技术的优缺点及适用性,并预测了城市河道水体恢复技术的发展趋势。
关键词 城市河道水 污染 恢复技术 发展趋势
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基于多元遥感影像数据的黄河上游滑坡发育特征研究 被引量:10
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作者 殷志强 秦小光 +1 位作者 赵无忌 魏刚 《工程地质学报》 CSCD 北大核心 2013年第5期779-787,共9页
黄河上游地区滑坡分布广泛,危害严重,是我国地质灾害的高易发区。文章以不同分辨率的多元遥感数据QuickBird(QB)、GeoEye、ZY-3、ZY-102C、Google earth等为数据源,结合野外现场实地调查和遥感验证等手段,开展了黄河上游地区滑坡发育... 黄河上游地区滑坡分布广泛,危害严重,是我国地质灾害的高易发区。文章以不同分辨率的多元遥感数据QuickBird(QB)、GeoEye、ZY-3、ZY-102C、Google earth等为数据源,结合野外现场实地调查和遥感验证等手段,开展了黄河上游地区滑坡发育的空间形态、展布特征研究,主要取得了以下认识:(1)研究区滑坡遥感影像特征明显,共发现各种类型的滑坡体508处,以群科—尖扎盆地分布数量最多;(2)滑坡的空间宏观展布形态主要有8种,岩土体类型主要有4类,并以泥岩滑坡发育数量最多;(3)滑体堆积体的长、宽主要集中在550~1500m和600~1500m,且长、宽呈两极化方向延展;(4)滑坡体的长度与前后缘的相对高程差和滑体平均坡度呈良好的线性关系。研究成果将为该地区严重的地质灾害防治提供基础地质依据。 展开更多
关键词 遥感影像 黄河上游 滑坡 发育特征
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云台山世界地质公园及周边地区河流阶地发育特征研究 被引量:3
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作者 章秉辰 王永成 +2 位作者 许连峰 张望生 董飞 《科学技术与工程》 北大核心 2015年第3期19-25,35,共8页
云台山世界地质公园位于太行山的南部边缘,源于太行山腹地的一系列河流,切穿太行峰脊,形成众多山高谷深瀑水飞溅的峡谷群,成为南太行山旅游的核心地质遗迹景观。峡谷中河流阶地发育,通过对云台山及周边地区九条典型峡谷中河流阶地发育... 云台山世界地质公园位于太行山的南部边缘,源于太行山腹地的一系列河流,切穿太行峰脊,形成众多山高谷深瀑水飞溅的峡谷群,成为南太行山旅游的核心地质遗迹景观。峡谷中河流阶地发育,通过对云台山及周边地区九条典型峡谷中河流阶地发育特征研究,探讨了河谷的发育历史;以及该地区不同时期的气候变化、新构造运动的性质和幅度,认为六级河流阶地在太行山河谷内普遍发育;但由于第四纪是强烈切割时期,所以这些河流阶地也大部分被剥蚀掉,仅在部分地区还不同程度残留有六级河流阶地的产物。 展开更多
关键词 云台山 峡谷 河流阶地 发育特征 地质公园
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内蒙河套地区黄河阶地与新近纪砾石层的发现及其对黄河发育、中国河流古老性与河湖共存论的意义 被引量:23
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作者 赵希涛 贾丽云 胡道功 《地质学报》 EI CAS CSCD 北大核心 2018年第4期845-886,共42页
通过内蒙河套地区的多次野外调查和多个横穿黄河河谷剖面的测量,热释光(OSL)与电子自旋共振(ESR)年龄样品的采集和测定,以及与黄河上中游其它河段和长江及中国其它河流河段的对比,从而取得了如下几方面的发现与认识:(1)河套地区不仅包... 通过内蒙河套地区的多次野外调查和多个横穿黄河河谷剖面的测量,热释光(OSL)与电子自旋共振(ESR)年龄样品的采集和测定,以及与黄河上中游其它河段和长江及中国其它河流河段的对比,从而取得了如下几方面的发现与认识:(1)河套地区不仅包括了具有多期湖泊发育,堆积了厚达数千米的晚新生代河湖相地层的断陷盆地,而且在其北侧的阴山山脉南麓,特别是南侧的鄂尔多斯高原北缘,还保存着拔河高度可达300m或更高的黄河9级阶地(T1~T9)。其中,T1的拔河高度2~12m,为内叠的堆积阶地,由松散的砂砾层组成,沿黄河及其支流均有分布。T2至T4,拔河高度分别为12~45m,28~80m和60~115m,阶地高度有自下游向上游变小的趋势。这些阶地大多分布在河套盆地之内,往往以河套古湖的湖相沉积为基座,在鄂尔多斯高原北缘,有时以三趾马红土或古近纪地层甚至基岩为基座,在阴山南麓,则以湖相地层、古近纪地层或基岩为基座,往往缺少三趾马红土。河套古湖的湖相沉积往往呈海拔1080~1100m的湖积台地出现,如在托克托东南表现最为明显。在湖积台地之上,有时能见到马兰黄土覆盖,其底部甚至有隐约的古土壤层S1出现。T5至T8,拔河高度分别为75~160m,130~200m,170~260m和250~295m,也有下游高差大、上游相对较小的趋势。组成阶地的砾石层或砂砾石层,有时与含1至多条古土壤的黄土互层,而以三趾马红土或古近纪地层甚至基岩为基座。有时在阶地沉积或三趾马红土之下,保存有河流相的砾石或砂砾石层,部分已被钙质胶结而成为砾岩或砂砾岩,显然是古黄河的沉积物。T9阶地我们只在黑赖沟剖面的两个地点发现,其拔河高度为290~315m,且下伏含有多达22层白色钙质结核层的三趾马红土的基座。(2)ESR与OSL测年结果表明,阶地的时代贯穿了整个第四纪时期。其中,T1形成于全新世中期:T2至T4分别形成于晚更新世晚期、中期和早中期;河套古湖沉积形成于晚更新世早期;T5~T9分别形成于中更新世晚期、中期、早期、早更新世晚期和早期。在黄河T5~T8之下,特别是其基座的三趾马红土之下所发现的古黄河的砾石层、砂砾层或胶结的砂砾层,其所夹砂层的石英热活化法ESR年龄测定结果为中新世或上新世。(3)研究表明,自新近纪以来,黄河不仅一直存在于强烈下沉的河套盆地,而且也徘徊在与其相伴的、长期持续但具有不同隆升幅度的阴山山脉南麓和鄂尔多斯高原北缘之间。这表明,即使在河套断陷的成湖时期,无论是断陷湖还是堰塞湖,黄河不仅可以从一端注入湖泊并从其另一端流出,而且河道也可以在湖泊的一侧或两侧流动。这就是河湖共存。(4)作者在对黄河整个上-中游及部分其它河段考察与研究的基础上还发现,自新近纪早中期以来,黄河就是一条上、下游贯通的古老大河,尽管古黄河的遗迹已受到不同地质构造单元的不同特征的地壳运动的影响而发生了巨大的破坏与变动,使其保存状况和连续性远不如第四纪不同时期的古黄河遗迹。(5)湖泊与河流是可以共存的。黄河并非泄空了某个断陷盆地(如三门古湖、河套古湖、贵德古湖、共和古湖等)才开始出现的,也不是第四纪以来因溯源侵蚀而逐段贯通的。黄河干流所流经的众多断陷盆地,可以多阶段成湖,也可以多次泄空;河道可以像现今梯级开发的水库而与古湖呈串珠状相连,也可以流经其旁与之并列;但黄河始终存在。(6)黄河自中新世早中期形成以来,可以深深地切割隆升地段的高山高原低山丘陵,形成沿途许多巨大的峡谷与多级河流阶地,也可以不断地充填所途经的强烈断陷地段的盆地谷地平原,形成巨厚的晚新生代地层,但黄河则始终存在,甚至在不同时期均能保留其大体呈抛物线状的河流纵剖面。(7)新近纪以来,黄河不仅一直存在于强烈下沉的河套盆地,而且也徘徊在与其相伴但具有不同隆升幅度的阴山山脉南麓和鄂尔多斯高原北缘之间。这表明,它不仅在不同河段可以同时穿越许多个隆升的高原山地和沉降的盆地平原,而且同一河段也可以游荡在隆升的山地或高原及下沉的平原或盆地之间。河套地区就是一个河湖多阶段共存的典型范例。(8)作者综合对黄河、长江等中国大型水系干流河谷发育问题的初步研究结果,提出如下几点想法供今后研究加以重视:(1)黄河与长江等中国其他典型的大型河流应该都是古老的,并且大多至少形成于中新世早中期,这就是中国河流的古老性。但因研究程度限制,目前对这些河流的最初发育情况并不清楚。(2)在河流的长期发育过程中,会由于内外动力的原因(如构造升降运动、断裂活动、地震、冰川作用、崩塌滑坡泥石流灾害等),在某一或某几个河段,会有一段或几段或长或短的时期,有构造湖或堰塞湖发育,但因河流规模巨大,始终能穿过这些湖泊或者在其旁流过,这就是河湖共存论。用湖泊贯通或河流袭夺解释中新世以来就已经存在的黄河、长江和中国其他河流是近期形成的观点,是值得商榷的。而要寻找黄河和中国其他河流的起源,是否由袭夺而来的问题,则至少要在中新世初或之前的古近纪去解决。(3)一条源远流长的大型河流一旦形成,由于其水量充沛,侵蚀与堆积能力很强,一般的内外动力作用都是难以阻挡的:它能穿过强烈活动的构造带并侵蚀切割因构造引起的隆升地段,在高山高原低山丘陵上形成峡谷或多级阶地;也能在长期下沉的盆地谷地平原中,不断地充填堆积,形成巨厚的冲积层,即使在其流经地区会有多段不同性质与幅度的升降运动不断地改变其纵剖面,但每条河流除其源头段的小河或冲沟外,在其绝大多数时段,都会大体保存其抛物线状的形状。受到调查研究程度的限制,目前仍无法完整地勾绘新近纪不同时期古黄河的位置和恢复其演变历史,也因缺少对河套断陷中的晚新生代地层的详细研究及其与断陷之外受到构造变动的古黄河沉积物的对比研究,而无法恢复其确切的升降运动幅度与速率,这些都期待能在今后的研究中加以解决。 展开更多
关键词 河套地区 河流阶地 古砾石层 晚新生代 黄河发育史 河湖共存
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金沙江上游沃达滑坡发育特征与堵江危险性分析 被引量:15
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作者 吴瑞安 马海善 +4 位作者 张俊才 杨志华 李雪 倪嘉伟 钟宁 《水文地质工程地质》 CAS CSCD 北大核心 2021年第5期120-128,共9页
金沙江上游沃达滑坡自1985年开始出现变形,现今地表宏观变形迹象明显,存在进一步失稳滑动和堵江的风险。采用遥感解译、地面调查、工程地质钻探和综合监测等方法,分析了沃达滑坡空间结构和复活变形特征,阐明了滑坡潜在复活失稳模式,并... 金沙江上游沃达滑坡自1985年开始出现变形,现今地表宏观变形迹象明显,存在进一步失稳滑动和堵江的风险。采用遥感解译、地面调查、工程地质钻探和综合监测等方法,分析了沃达滑坡空间结构和复活变形特征,阐明了滑坡潜在复活失稳模式,并采用经验公式计算分析了滑坡堵江危险性。结果表明:沃达滑坡为一特大型滑坡,体积约28.81×10^(6) m^(3),推测其在晚更新世之前发生过大规模滑动;滑坡堆积体目前整体处于蠕滑变形阶段,局部处于加速变形阶段;复活变形范围主要集中在中前部,且呈现向后渐进变形破坏特征,复活区右侧变形比左侧强烈。滑坡存在浅层和深层两级滑面,平均埋深分别约15.0,25.5 m,相应地可能出现两种潜在失稳模式:滑坡强变形区沿浅层滑带滑动失稳时,形成的堵江堰塞坝高度约87.2 m;滑坡整体沿深层滑带滑动失稳时,形成的堵江堰塞坝高度约129.2 m。沃达滑坡存在形成滑坡-堵江-溃决-洪水链式灾害的危险性,建议进一步加强滑坡监测,针对性开展排水、加固等防治工程。 展开更多
关键词 金沙江上游 沃达滑坡 发育特征 复活模式 堵江危险性
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