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基于PS-InSAR的珠江口典型填海造地区地面沉降时空特征研究
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作者 曾敏 皮鹏程 +5 位作者 赵信文 陈松 彭红霞 侯清芹 孙慧敏 薛紫萱 《华南地质》 CAS 2023年第1期116-126,共11页
近年来,珠三角地区经济发展迅速,人类活动加剧,软土自固结作用诱发的地面沉降范围与程度逐渐扩大,严重制约城市建设,危害居民人身财产安全。本文以珠江口典型填海区为例,基于2015年12月至2016年12月的24幅Sentinel-1A SAR数据影像,应用P... 近年来,珠三角地区经济发展迅速,人类活动加剧,软土自固结作用诱发的地面沉降范围与程度逐渐扩大,严重制约城市建设,危害居民人身财产安全。本文以珠江口典型填海区为例,基于2015年12月至2016年12月的24幅Sentinel-1A SAR数据影像,应用PS-InSAR监测地面沉降状态,通过设置可靠PS点,计算沉降速率,提取地面沉降时序特征。结果表明,该时间段内研究区的地面沉降较为严重,整体年均沉降速率为-7.65 mm/a,其中鸡抱沙-孖沙垦区南部、万顷沙地区以及南朗横门三地尤为严重,相继出现四个典型沉降区,最大沉降量达117.48 mm;并通过实地监测数据验证其精度具备高可靠性,该研究可为珠江口城市建设合理规划、地面沉降防治工作提供科学依据。 展开更多
关键词 填海造地区 PS-INSAR 地面沉降 时序特征 珠江口
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浅析填海造地区软基处理方案
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作者 柯河山 《江西建材》 2020年第12期207-208,210,共3页
文中结合工程实例,详细研究了软基处理的浮筒式水泥搅拌方案,并和传统的施工方法进行比对分析。
关键词 浮筒式水泥搅拌桩 特殊路基 造地区 问题
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大别造山带北麓地区自石炭纪以来构造演化研究
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作者 邵明辰 王笔梁 《吉林地质》 2012年第1期17-20,26,共5页
大别造山带北麓地区位于大别造山带外侧缘,其构造演化过程严格受大别造山过程的控制。大别造山带北麓地区构造热史的恢复对于整个大别造山带造山过程的研究具有重要意义。造山带外缘复杂的构造演化过程,造成了其埋藏史恢复的复杂性。在... 大别造山带北麓地区位于大别造山带外侧缘,其构造演化过程严格受大别造山过程的控制。大别造山带北麓地区构造热史的恢复对于整个大别造山带造山过程的研究具有重要意义。造山带外缘复杂的构造演化过程,造成了其埋藏史恢复的复杂性。在综合分析该地区石炭系上覆地层分布、侵入岩中矿物结晶压力以及构造运动发展阶段等多方面资料的基础上,以全新的思路恢复了大别造山带北麓地区石炭系埋藏史,分析认为,自石炭纪以来,大别造山带北麓地区共经历了三次沉降和三次隆升的演化过程。 展开更多
关键词 大别山带北麓地区 埋藏史 演化 三次沉降和三次隆升
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分形理论在剖面缩短量研究中的应用 被引量:3
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作者 施泽进 曾庆 《中国海上油气(地质)》 CAS 1995年第3期191-197,共7页
总缩短量的确定对岩层变形的定量研究有着重要意义。复杂构造地区的层面在二维平面内可看作为一条曲线,从而可运用分形几何学的方法由分数维来定量描述。利用自相似分形和自仿射分形的概念,建立了计算缩短量的数学模型,以川东大池干... 总缩短量的确定对岩层变形的定量研究有着重要意义。复杂构造地区的层面在二维平面内可看作为一条曲线,从而可运用分形几何学的方法由分数维来定量描述。利用自相似分形和自仿射分形的概念,建立了计算缩短量的数学模型,以川东大池干构造的85-D362剖面为例,进行了缩短量和剖面应变计算,分形分析结果表明,Tc顶层曲面的分维值为1.0897,缩短量在11km,表现现47.844%的应变。要正确地平衡地质剖面,必须对小尺度范围的应变进行分析。 展开更多
关键词 分形理论 剖面缩短量 研究 应用 岩层变形 推覆山带地区 分数维 应变
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Introduction of Pinus radiata for afforestation:a review with reference to Aba, China
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作者 毕慧泉 Jack Simpson +4 位作者 李荣伟 颜红 吴宗兴 蔡诗民 Robert Eldridge 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第4期311-322,共12页
Pinus radiata D. Don, native to a Californian coastal environment, has been introduced to many parts of the world as an exotic species for afforestation. It is now a major plantation species in the Southern Hemisphere... Pinus radiata D. Don, native to a Californian coastal environment, has been introduced to many parts of the world as an exotic species for afforestation. It is now a major plantation species in the Southern Hemisphere. In 1990, it was introduced to the heavily degraded, dry Min river valley area in Aba prefecture of Sichuan Province, P. R. China. Survival and growth of young trees planted at several sites appear to be reasonable. This review is to serve as an introduction to the large body of literature on P. radiata for forest scientists in China. It covers the following aspects: P. radiata in its native environment and in ex situ plantations, provenance and genetic variations, environmental limitations and climate niche, diseases and pests, lessons from unsuccessful introductions, and the use of P. radiata for ecological restoration. The early growth of P. radiata planted in the dry river valley area is briefly described. Potential problems associated with the introduction of P. radiata in Aba and future research needs are also identified. 展开更多
关键词 Pinus radiata Species introduction Ecological restoration Dry river valley.
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Reforestation Programs in Southwest China:Reported Success,Observed Failure, and the Reasons Why 被引量:12
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作者 Christine Jane Trac Stevan Harrell +1 位作者 Thomas M. Hinckley Amanda C. Henck 《Journal of Mountain Science》 SCIE CSCD 2007年第4期275-292,共18页
Ever since the disastrous floods of 1998, the Chinese government has used the Natural Forest Protection and Sloping Land Conversion Programs to promote afforestation and reforestation as means to reduce runoff, contro... Ever since the disastrous floods of 1998, the Chinese government has used the Natural Forest Protection and Sloping Land Conversion Programs to promote afforestation and reforestation as means to reduce runoff, control erosion, and stabilize local livelihoods. These two ambitious programs have been reported as large-scale successes, contributing to an overall increase in China’s forest cover and to the stated goals of environmental stabilization. A small-scale field study at the project level of the implementation of these two programs in Baiwu Township, Yanyuan County, Sichuan, casts doubt upon the accuracy and reliability of these claims of success; ground observations revealed utter failure in some sites and only marginal success in others. Reasons for this discrepancy are posited as involving ecological, economic, and bureaucratic factors. Further research is suggested to determine whether these discrepancies are merely local aberrations or represent larger-scale failures in reforestation programs. 展开更多
关键词 FORESTS AFFORESTATION REFORESTATION grain-to-green natural forest protection plan China SICHUAN Liangshan
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Effect of Afforestation on Soil Properties and Mycorrhizal Formation 被引量:1
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作者 P. KAHLE C. BAUM B. BOELCKE 《Pedosphere》 SCIE CAS CSCD 2005年第6期754-760,共7页
A study was conducted on Cambisols in Northern Germany to analyze the effect of fast growing trees (Salix and Populus spp.) used in agroforestry on soil chemical and physical properties and also on endo- and ectomyc... A study was conducted on Cambisols in Northern Germany to analyze the effect of fast growing trees (Salix and Populus spp.) used in agroforestry on soil chemical and physical properties and also on endo- and ectomycorrhizal colonization of the fine roots. Representative plots of three trials, Giilzow (GUL), Vipperow (VIP) and Rostock (ROS), were used to measure the topsoil inventories at the very beginning and after six (GUL), seven (VIP) and ten (ROS) years of afforestation with fast growing trees. The effect on soil organic carbon, plant available nutrients, reaction, bulk density, porosity and water conditions was analyzed, Arable soils without tree coppice were used as controls. Additionally, the endoand ectomycorrhizal colonization of two Salix and two Populus clones were investigated at one site (GUL) in 2002. The amounts of organic carbon in the topsoil increased significantly (P 〈 0.01) presumably induced by leaf and root litter and also by the lack of tillage. The soil bulk density significantly decreased and the porosity of the soil increased significantly (both P 〈 0.01). The proportion of medium pores in the soil also rose significantly (P 〈 0.05 and 0.01). Generally, afforestation of arable soils improved soil water retention. Ectomycorrhizas dominated the mycorrhizal formation of the Salix and Populus clones, with the accumulation of organic matter in the topsoil suspected of supporting the ectomycorrhizal formation. Thus, agroforestry with Salix and Populus spp. conspicuously affected chemical and additionally physical properties of the top layer of Cambisols within a period of six years. 展开更多
关键词 AGROFORESTRY fast growing tree MYCORRHIZA soil organic matter soil water retention
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Neogene coupling between Kuqa Basin and Southern Tien Shan Orogen, Northwestern China 被引量:3
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作者 何光玉 陈汉林 《Journal of Zhejiang University Science》 EI CSCD 2004年第8期970-975,共6页
Based on the sedimentary and subsiding features of Kuqa foreland basin, this paper presents the following characteristics of Neogene coupling relationship between Kuqa Basin and Southern Tien Shan Orogen, Northwester... Based on the sedimentary and subsiding features of Kuqa foreland basin, this paper presents the following characteristics of Neogene coupling relationship between Kuqa Basin and Southern Tien Shan Orogen, Northwestern China: (1) The Southern Tien Shan Orogen underwent Neogene uplifting of 4 km in height and the Kuqa Basin underwent Neogene subsidence of 4?6 km in depth accordingly beginning in 25 Ma; (2) The Southern Tien Shan Orogen moved continuously toward the Kuqa Basin, with largest structural shortening rate of greater than 53.7%, and the north boundary of the Kuqa Basin retreated continuously southward accordingly since the Miocene; (3) There are two subsidence centers with high subsiding rates and large subsiding extent, located in the eastern and western Kuqa Basin respectively, with the subsiding maximizing in the deposition period of Kuqa Formation. 展开更多
关键词 Kuqa Basin Southern Tien Shan Coupling between basin and orogen NEOGENE
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Relationships and Evolving Networks of Rural Manufacturing Clusters: A Case Study in Yucheng County, Henan Province of China 被引量:7
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作者 LI Erling LI Xiaojian LIU Zhigao 《Chinese Geographical Science》 SCIE CSCD 2011年第3期364-376,共13页
The evolution of networks in rural industrial clusters,in particular in the context of China has been paid more attention to in the world.Applying the theory and techniques of social network analysis (SNA),this study ... The evolution of networks in rural industrial clusters,in particular in the context of China has been paid more attention to in the world.Applying the theory and techniques of social network analysis (SNA),this study is with particular regard to the business network relationships and their evolutionary dynamics of steel measuring tape manufacturing clustered in Nanzhuang Village,Yucheng County of Henan Province,China,which is important for better understanding the industrial and regional development in less developed rural areas.From data collected by comprehensive questionnaire survey in 2002 and mass interviews with 60 enterprises and assembling families and several government authorities in 2002,2003,2004,2005 and 2008,four types of networks are identified: spin-off,consulting,communication and cooperative.The characteristic of these networks is outlined in detail.Compared with the high-tech clusters of typical developed areas,the networks that have evolved in traditional manufacturing clusters are more affected by emotive linkages.The cluster networks are shown to exhibit a polycentric hierarchical structure.The family relationships are the dominate spin-off channels of enterprises,while the supply and demand relationships and the mobility of the skilled workers are also important paths of network learning,and the cooperation relationships are comparatively stable.Besides the root enterprises,the middle-sized enterprises are comparatively more active than small-sized enterprises,and the intermediary agencies and the service institutions act as bridges of the inter-enterprises cooperation.By analysis of the structure of networks and the interactions between the networks,the four stages of network evolution are also identified.The four stages are dominated by the family networks,the internal division production networks,the local innovation networks and the global supply networks respectively,and they play different roles in cluster development. 展开更多
关键词 evolution dynamics cluster network less developed rural area steel measuring tape manufacturing cluster social network analysis
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Soil animals and nitrogen mineralization under sand-fixation plantations in Zhanggutai region,China 被引量:8
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作者 CHEN Fu-sheng ZENG De-hui +2 位作者 HU Xiao-fei CHEN Guang-sheng YU Zhan-yuan 《Journal of Forestry Research》 SCIE CAS CSCD 2007年第1期73-77,共5页
The effects of soil animals on soil nitrogen (N) mineralization and its availability were studied by investigating soil animal groups and their amounts of macro-faunas sorted by hand, and middle and microfaunas distin... The effects of soil animals on soil nitrogen (N) mineralization and its availability were studied by investigating soil animal groups and their amounts of macro-faunas sorted by hand, and middle and microfaunas distinguished with Tullgren and Baermann methods under three Pinus sylvestris var. mongolica Litv. plantations in Zhanggutai sandy land, China. In addition, soil N mineralization rate was also measured with PVC closed-top tube in situ incubation method. The soil animals collected during growing season belonged to 13 orders, 5 groups, 4 phyla, whose average density was 86 249.17 individuals·m^(-2). There were significant differences in soil animal species, densities, diversities and evenness among three plantations. Permanent grazing resulted in decrease of soil animal species and diversity. The average ammonification, nitrification and mineralization rates were 0.48 g·m^(-2)·a^(-1), 3.68 g·m^(-2)·a^(-1) and 4.16 g·m^(-2)·a^(-1), respectively. The ammonification rate in near-mature forest was higher than that in middle-age forests, while the order of nitrification and net mineralization rates was: middle-age forest without grazing < middle-age forest with grazing < near-mature forest with grazing (P<0.05). Soil N mineralization rate increased with soil animal amounts, but no significant relationship with diversity. The contribution of soil animals to N mineralization was different for different ecosystems due to influences of complex factors including grazing, soil characteristics, the quality and amount of litter on N mineralization. 展开更多
关键词 Soil animals N mineralization Pinus sylvestris var. mongolica Litv. Zhanggutai sandy land
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FIas the "Flying Geese" Paradigm Occurred in China? 被引量:2
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作者 Qu Yue Cai Fang Zhang Xiaobo 《China Economist》 2013年第6期18-30,共13页
In economic literature, the term 'flying geese" refers to the movement of capital from developed regions to less developed ones. Using national data from abovescale manufacturing enterprises, this paper investigates... In economic literature, the term 'flying geese" refers to the movement of capital from developed regions to less developed ones. Using national data from abovescale manufacturing enterprises, this paper investigates whether the experience of "flying geese" has transpired in China for manufacturing industries. We find that, driven by the effects of agglomeration, prior to the mid-2000s, there had been an increasing concentration of industrial activities in the coastal regions. However, as labor and land costs increased, the manufacturing sector - especially the labor-intensive industries - began to relocate from the coastal to the interior regions. 展开更多
关键词 manufacturing industries flying geese industrial cluster
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On the Tectonic Problems of the Southern East China Sea and Adjacent Regions:Evidence from Gravity and Magnetic Data 被引量:2
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作者 SHANG Luning ZHANG Xunhua +1 位作者 HAN Bo DU Runlin 《Journal of Ocean University of China》 SCIE CAS 2016年第1期93-106,共14页
In this paper, two sets of gravity and magnetic data were used to study the tectonics of the southern East China Sea and Ryukyu trench-arc system: one data set was from the 'Geological-geophysical map series of Chin... In this paper, two sets of gravity and magnetic data were used to study the tectonics of the southern East China Sea and Ryukyu trench-arc system: one data set was from the 'Geological-geophysical map series of China Seas and adjacent areas' database and the other was newly collected by R/VKexue Ⅲ in 2011. Magnetic and gravity data were reorganized and processed using the software MMDP, MGDP and RGIS. In addition to the description of the anomaly patterns in different areas, deep and shallow structure studies were performed by using several kinds of calculation, including a spectrum analysis, upward-continuation of the Bouguer anomaly and horizontal derivatives of the total-field magnetic anomaly. The depth of the Moho and magnetic basement were calculated. Based on the above work, several controversial tectonic problems were discussed. Compared to the shelf area and Ryukyu Arc, the Okinawa Trough has an obviously thinned crust, with the thinnest area having thickness less than 14km in the southern part. The Taiwan-Sinzi belt, which terminates to the south by the NW-SE trending Miyako fault belt, contains the relic volcanic arc formed by the splitting of the paleo Ryukyu volcanic arc as a result of the opening of the Okinawa Trough. As an important tectonic boundary, the strike-slip type Miyako fault belt extends northwestward into the shelf area and consists of several discontinuous segments. A forearc terrace composed of an exotic terrane collided with the Ryukyu Arc following the subduction of the Philippine Sea Plate. Mesozoic strata of varying thicknesses exist beneath the Cenozoic strata in the shelf basin and significantly influence the magnetic pattern of this area. The gravity and magnetic data support the existence of a Great East China Sea, which suggests that the entire southern East China Sea shelf area was a basin in the Mesozoic without alternatively arranged uplifts and depressions, and might have extended southwestward and connected with the northern South China Sea shelf basin. 展开更多
关键词 TECTONICS southern East China Sea Ryukyu trench-arc system gravity anomaly magnetic anomaly
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Relationship of hydrocarbon and source-rock in Nos.3-5 tectonic belts of the Lenghu area,northern Qaidam Basin 被引量:2
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作者 WANG Chao-yong ZHANG Ming +2 位作者 YIN Cheng-ming JIANG Bo BAO Yuan 《Mining Science and Technology》 EI CAS 2009年第6期796-799,共4页
Based on analyses of the components of crude oil hydrocarbons and carbon isotopes,the content of normal alkane decreased from 49.00% to 20.10% when moving from the No.3 to No.5 tectonic belt of the Lenghu area of the ... Based on analyses of the components of crude oil hydrocarbons and carbon isotopes,the content of normal alkane decreased from 49.00% to 20.10% when moving from the No.3 to No.5 tectonic belt of the Lenghu area of the Qaidam Basin,while cycloalkanes increased from 30.00% to 52.20% and aromatic and branch chain alkanes increased gradually as well. The maturity of sterane in crude oil is higher than that of its source-rock,which shows that the hydrocarbons were generated from a deep source-rock of high maturity around the tectonic belts of the Lenghu area. The analysis of the characteristics of carbon isotopes also shows that these isotopes of hydrocarbon compounds in the No.4 and No.5 tectonic belt are apparently heavier than those in the No.3 belt. The results of our research show that the hydrocarbons in the No.3 tectonic belt are mainly from a relatively rich sapropelic substance,while the hydrocarbons in the No.4 and No.5 tectonic belt originated mainly from organic matter of a relatively rich humic type substance. 展开更多
关键词 Qaidam Basin JURASSIC carbon isotope SAPROPEL HUMUS
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Petrology, geochemistry and geodynamics of basic granulite from the Altay area, North Xinjiang, China 被引量:3
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作者 厉子龙 陈汉林 +2 位作者 杨树锋 董传万 肖文交 《Journal of Zhejiang University Science》 EI CSCD 2004年第8期979-984,共6页
The basic granulite of the Altay orogenic belt occurs as tectonic lens in the Devonian medium- to lower-grade metamorphic beds through fault contact. The Altay granulite (AG) is an amphibole plagioclase two-pyroxene ... The basic granulite of the Altay orogenic belt occurs as tectonic lens in the Devonian medium- to lower-grade metamorphic beds through fault contact. The Altay granulite (AG) is an amphibole plagioclase two-pyroxene granulite and is mainly composed of two pyroxenes, plagioclase, amphibole and biotite. Its melano-minerals are rich in Mg/(Mg+Fe2+), and its amphibole and biotite are rich in TiO2. The AG is rich in Mg/(Mg+Fe2+), Al2O3 and depletion of U, Th and Rb contents. The AG has moderate ∑REE and LREE-enriched with weak positive Eu anomaly. The AG shows island-arc pattern with negative Nb, P and Ti anomalies, reflecting that formation of the AG may be associated with subduction. Geochemical and mineral composition data reflect that the protolith of the AG is calc-alkaline basalt and formed by granulite facies metamorphism having peak P-T conditions of 750 °C?780 °C and 0.6?0.7 Gpa. The AG formation underwent two stages was suggested. In the early stage of oceanic crustal subduction, calc-alkaline basalt with island-arc environment underwent granulite facies metamorphism to form the AG in deep crust, and in the late stage, the AG was thrust into the upper crust. 展开更多
关键词 Basic granulite Petrology and geochemistry GEODYNAMICS Altay orogenic belt North Xinjiang
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Types and Causes of Debris Flow Damage to Drainage Channels in the Wenchuan Earthquake Area 被引量:10
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作者 CHEN Jian-gang CHEN Xiao-qing +2 位作者 WANG Tao ZOU Yu-hua ZHONG Wei 《Journal of Mountain Science》 SCIE CSCD 2014年第6期1406-1419,共14页
Debris flows are among the most common geological disasters in China,and have been particularly frequent in Sichuan Province since the Wenchuan earthquake on 12 May 2008.The construction of debris flow drainage channe... Debris flows are among the most common geological disasters in China,and have been particularly frequent in Sichuan Province since the Wenchuan earthquake on 12 May 2008.The construction of debris flow drainage channels is a countermeasure used to distribute debris flow fans,and these channels play a critical role in the mitigation and prevention of damage resulting from debris flows.Under field conditions,the useful life of drainage channels can be greatly shortened as a result of strong abrasions to the drainage structure caused by the debris flow.Field investigations have shown that the types of damage to drainage channels include(a) erosion caused by hyper-concentrated silt flow,(b) impact fractures and foundation scour at the groundsills of the drainage channel,(c) destruction of the drainage channel outlet,and(d) destruction of the drainage channel caused by debris flow abrasion.In addition,based on the destruction of the drainage channel during the debris flow drainage process,a new type of drainage channel with energy dissipation components was proposed and applied in a steep,narrow gully for debris flow mitigation.Moreover,design and engineering repair recommendations for drainage channels are provided as a reference for repairing the damage to the channel.The results can provide an important reference for the effective repair and optimal design of drainage channels. 展开更多
关键词 Debris flow Drainage channel Damage type Wenchuan earthquake Geological disaster
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Seismic Ground Motion Zoning Maps of the Pangxi Region
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作者 Lei Jiancheng, Zhang Yaoguo, Zhou Rongjun, Pu Xiaohong and Huang ZuzhiSeismological Bureau of Sichuan Province, Chengdu 610041, China 《Earthquake Research in China》 2002年第4期315-331,共17页
The seismotectonic environment and seismic activity in Southwest China region were studied based on new data and new results obtained during the Eighth and Ninth Five-Year Plans, the seismic areas and zones and potent... The seismotectonic environment and seismic activity in Southwest China region were studied based on new data and new results obtained during the Eighth and Ninth Five-Year Plans, the seismic areas and zones and potential seismic source zones were determined, and the relation between seismic activity parameters and ground motion attenuation was determined. Finally the seismic ground motion zoning maps of the Pangxi region was compiled by using the multi-parameter and multi-scheme method. 展开更多
关键词 Pangxi region Seismic ground motion Zoning maps Multiple parameter Multiple scheme
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Large-Scale Dextral Strike-Slip Movement and Associated Tectonic Deformation Along the Red-River Fault Zone
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作者 Xiang Hongfa Han Zhujun +2 位作者 Guo Shunmin Zhang Wanxia Chen Lichun 《Earthquake Research in China》 2005年第2期125-138,共14页
Field investigation has revealed that the large-scale dextral strike-slip movement and the associated tectonic deformation along the Red River fault zone have the following features: geometrically, the Red River fault... Field investigation has revealed that the large-scale dextral strike-slip movement and the associated tectonic deformation along the Red River fault zone have the following features: geometrically, the Red River fault zone can be divided into three deformation regions, namely, the north, central and south regions. The north region lies on the eastern side of the Northwest Yunnan extensional taphrogenic belt, which is characterized by the 3 sets of rift-depression basins striking NNW, NNE and near N-S since the Pliocene time, and on its western side is the Lanping-Yunlong compressive deformation belt of the Paleogene to Neogene; the deformation in the central region is characterized by dextral strike-slip or shearing. The east Yunnan Miocene compressive deformation belt lies on the eastern side of the fault in the south, and the Tengtiaohe tensile fault depression belt is located on its west. In terms of tectonic geomorphology, the aforementioned deformation is represented by basin-range tectonics in the north, linear faulted valley-basins in the central part and compressive (or tensional) basins in the south. Among them, the great variance in elevation of the planation surfaces on both sides of the Cangshan-Erhai fault suggests prominent normal faulting along the Red River fault since the Pliocene. From the viewpoint of spatial-temporal evolution, the main active portion of the fault was the southern segment in the Paleogene-Miocene-Pliocene, which is represented by “tearing” from south to north. The main active portion of the fault has migrated to the northern segment since the Pliocene, especially in the late Quaternary, which is characterized by extensional slip from north to southeast. The size of the deformation region and the magnitude of deformation show that the eastern plate of the Red River fault has been an active plate of the relative movement of blocks. 展开更多
关键词 Extensive-strike slip-compressive deformation Tectonic geomorphology MIOCENE Red River fault zone Southwest China
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Road-Spine versus Road-Tube: Roads as Space Generators
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作者 Alfonso Annunziata 《Journal of Civil Engineering and Architecture》 2016年第8期901-911,共11页
Arteries devoted to sustain streams of users, resources and debris, are a foremost factor and pre-condition of the development of urban areas and of the transformation of landscapes. Roadscapes reflect outcomes relate... Arteries devoted to sustain streams of users, resources and debris, are a foremost factor and pre-condition of the development of urban areas and of the transformation of landscapes. Roadscapes reflect outcomes related to super urbanization tendencies. Often conceived as isolated tubes, roads cut and obscure form, structure, biotic and abiotic factors of sites, urban fabrics and spaces. A broad vision of landscape is a basis for reconceiving roads. The concept of road-spine emerges: the road is conceived as the basis of a bundle of routes, nodes, surfaces, poles and tiles, devised to frame and shape a mosaic of open spaces, crops, farms, stores, basins and service areas. The road-spine entails the idea of a permeable infrastructure devised to integrate diverse functions: from serving various forms of motion, by ordering an isotropic grid of routes, to framing a porous urbanscape; from disposing surfaces meant to preserve biocenosis and biotopes, to favoring osmosis amid land uses. It also prefigures a distribution of land uses dependent on site vocations, and a mosaic of scenarios open to encounter, evasion, rest, amusement, participation, and to spontaneous practices of space. 展开更多
关键词 Infrastructure LANDSCAPE open space edge road.
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Process of Salinisation of a Lagoon and a Coastal Aquifer in Annaba Area (East Algerian)
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作者 Mekkakia Mokhtaria Larbi Djabri +4 位作者 Chemseddine Fehdi Fethi Baali Azzedine Hani Antonio Pulido Bosch Saad Bouhsina 《Journal of Agricultural Science and Technology(A)》 2013年第12期973-981,共9页
The study area is located in a Mediterranean region, so the effects of the climate variations are very important. The authors contribution to this subject is based on the compilation of many results obtained from diss... The study area is located in a Mediterranean region, so the effects of the climate variations are very important. The authors contribution to this subject is based on the compilation of many results obtained from dissertations and theses that are carried out under their supervision. The main tool used, in addition to other methods, is the water hydrochemistry as it is proved very useful in obtaining good results and helpful in getting objective interpretations regarding the presence and absence of salinity. Several factors are undertaken to show the presence of salts in waters in the plain, the lithology of the geological formations shows that they are composed of alluvium sediments where the permeability is quite high, and this enables hydraulic communication between the fresh water of the aquifer and saline water of the sea. The study of climate shows a decrease of precipitation which favors an important decrease of recharge rate to the aquifer, and hence a decrease of water resource. The strontium which is a good indicator for the origin of salinity shows a variation that indicates a variation in the distribution of the salinity, and therefore diverse origins of salinity all over the studied area. This can infer the presence of marine invasion in the down-stream part of the aquifer, whereas elsewhere salinity is caused by the presence of evaporitic formation, mainly by the argillaceous matrix in the bottom of the lake. in the up-stream part of the aquifer. In the lake, salinity is explained 展开更多
关键词 LAKE river sea marine invasion AQUIFER TRANSMISSIVITY evaporitic.
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Research on the Seismotectonic Zones and Seismicity State in the Southern Xinjiang Region
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作者 Qu Yanjun Wang Qiong Nie Xiaohong 《Earthquake Research in China》 2012年第2期222-233,共12页
Based on the studies of earthquake activity, tectonic movement, crustal shortening rate, fault activity, local stress field and historical characteristics of strong earthquake activities in Xinjiang, we divide the sou... Based on the studies of earthquake activity, tectonic movement, crustal shortening rate, fault activity, local stress field and historical characteristics of strong earthquake activities in Xinjiang, we divide the south part of Xinjiang into 4 seismotectonic zones, namely, the eastern segment of south Tianshan seismic belt, the Kalpin block, the Kashi-Wuqia junction zone, and the west Kunlun Mountains seismic belt. Using earthquake catalogues from Xinjiang since 1900, and on the basis of integrity analysis of earthquake records in different magnitude ranges, the seismicity state of different seismotectonic zones is analyzed quantificationaUy by calculating the mean value of annual strain energy release, annual rate of earthquakes with different lower limits of magnitude, b-value, and the parameter m of accelerating strain release model. The characteristic indexes of seismicity state for each of the seismic tectonic zones are then determined, which provide a quantitative basis for earthquake tendency analysis and judgment. 展开更多
关键词 Southern Xinjiang Seismotectonic zone Seismicity state
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