检索结果-南通市图书馆

Mesozoic contraction deformation in the Yanshan and northern taihang mountains and its implications to the destruction of the North China Craton

引用

Science China Earth Sciences 2011年第6期54卷 798-822页

作者： ZHANG ChangHou LI ChengMing DENG HongLing LIU Yang LIU Lei WEI Bo LI HanBin LIU Zi State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China

Mesozoic contraction deformation in the Yanshan and taihang mountains is characterized by basement-involved thrust tectonics,basement-cored buckling anticlines and ductile thrust and nappe *** of these deformations are orientated west-east,west-northwest and northeast to *** contraction deformations began in the Permian,continued through the Triassic and Jurassic and terminated in the Early Cretaceous,and constitute an important part of the destruction of the North China *** is estimated,from balanced cross-section reconstructions,that the north-south shortening of the central part of the Yanshan belt before 135 Ma was around 38%.The initial crust thickness,pre-dating the major contraction deformation in late Paleozoic and early Mesozoic,was estimated to be around 35 km based on paleogeographic *** that the inferred depth of ductile thrusting deformation,20-25 km,was the crust thickness involved in the contraction deformation,and also assuming that the N-S contraction deformation was accommodated by vertical crust thickening,the thickness of the crust after the contraction deformation was expected to be around 47-50 *** was the approximate crust thickness required for the eclogitization of the lower crust for *** gravity potential accumulated by the isostatic uplift of the thickened crust,together with the decrease in crustal strength caused by the coeval magmatisms associated with the contraction deformation,led to the subsequent extensional collapse of the middle and upper crust although the regional stress regime associated with the plate interactions remained *** is inferred that the Mesozoic contraction deformations in the Yanshan and taihang mountains were not only a significant tectonic process contributing to the destruction of the craton in middle and upper crust but also stimulated delamination at a deep level and the extension of the shallow *** other words,both the suspec

关键词： North China Craton Yanshan belt taihang mountain contraction deformation gravitational collapse

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Features and values of geological heritage resources in Shunping County,Hebei Province

引用

Journal of Groundwater Science and Engineering 2020年第4期8卷 349-357页

作者： YANG Jin-song LIU Zhe WANG Xiang-dong ZHAO Hua SONG lei LIU Tai-bei WANG Cheng-min ZHANG Peng Institute of Hydrogeology and Environmental Geology Chinese Academy of Geological SciencesShijiazhuang 050061China Key Laboratory of Quaternary Chronology and Hydro-Environmental Evolution China Geological SurveyShijiazhuang 050061China Institute of Geology China Earthquake AdministrationBeijing 100037China Qiqihar University QiqiharHeilongjiang Province 161006China

Hebei Province is rich in geological heritage resources due to its diverse landforms and unique natural ***,detailed investigation and study of the resources are still limited,and a systematic survey conducted on a small scale has not been fully *** this paper,the resource types and characteristics of the geological heritage in Shunping County are systematically discussed,on the basis of field investigation and scientific *** reference to the existing criteria for geological heritage resources survey,the heritage values and corresponding levels were assessed by using multi-factor quantitative evaluation *** results show that there are 33 geological heritage sites in Shunping County,which fall into 3 categories,10 classes and 17 *** them,2 heritage sites are above the provincial level,14 heritage sites are at the provincial level and 17 ones are below the *** heritage sites are not only natural resources with great tourism potential,but also valuable asset in geological research,human history,ecological conservation,scientific education and some other *** is hence of great significance to conduct the scientific and reasonable appraisal for having a better understanding,good protection and development of the geological heritage resources in Hebei Province.

关键词： Geological heritage Landscape assessment Hebei Province Shunping County taihang mountain

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Pollen assemblages of cultivated vegetation in central and southern Hebei Province

引用

Journal of Geographical Sciences 2011年第3期21卷 549-560页

作者： PANG Ruiming College of Resources and Environment of Hebei Normal University Shijiazhuang 050016 China Key Laboratory of Environmental Change and Ecological Development of Hebei Province Shijiazhuang 050016 China

The study on 82 surface soil pollen samples from different types of cultivated vegetations in central and southern parts of Hebei Province indicates that the pollen assem- blages from farmlands in the plain have not only their own plant types, but also the pollen components from the nearby mountains. Arboreal pollen percentages and concentrations （dominated by Pinus） from farmlands in mountain area are higher than those in the plain, and it reduces gradually with the increasing distance away from the mountains. Taking Pinus pollen in taihang mountains as an example, its content is 20%-30%, 10%-20%, 20%-30% and below 16% respectively for the samples from the area of 0-50, 50-100, 100-150 and more than 150 km away from the east taihang mountains. The increase of Pinus pollen proportion in the central plain is probably related to the fohn effect. The spatial variation of AP from mountains to the plain in Hebei Province may be similar to the forests clearance by human activities in the early historical period. Shrubby pollen proportion is small both in mountains and in the plain, but their major components are different. Elaeagnaceae, Corylus, Ostryopsis and Oleaceae are common in mountain areas, while there are relatively high contents of Rosaceae and Vitaceae in the plain. Herbs content in the plain （about 60%） is 15% higher than that in mountains, among which the Cereals and Cruciferae pollen percentages are 5% and 2% higher respectively. Artemisia pollen percentage in the plain is lower than that in mountains. Since the human activities are weaker in mountains compared with that in the plain, the general trend is that Chenopodiaceae pollen increases from mountains to the plain gradually, reflecting the raising intensity of human activities. The fern spores of Selaginella sinensis in mountains are higher than that in the plain, but it still reaches to about 7% in the plain. The fern spores of Selaginella sinensis are not prone to be spread by wind, indicating that th

关键词： farmlands human activity pollen assemblages taihang mountain plain Hebei Province

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

河北藓类植物的新记录与新分布(英文)

河北藓类植物的新记录与新分布(英文)

引用

作者：李琳王晓蕊李敏赵建成 College of Life Science Hebei Normal University College of Huihua Hebei Normal University

Nine species,Bryoerythriophyllum alpigenum(Vent.) Chen,Hyophila nymaniana(Fleisch.) Menzel, Phascum cuspidatum Hedw.,Dichodontium pellucidum(Hedw.)Schimp.,Ptychomitrium fauriei Besch., Tetraplodon mnioides(Hedw.) B.S.G,Plagiopus oederiana(Sw.) Crum et Anderson,Erythrodontium pallidifolium C.M(u|¨)*** Hylocomium splendens(Hedw.) B.S.G,are reported for the first time from Hebei *** to the specimens,identification features,major references,collected sites,characteristics of the habitat and distribution of every species are *** addition,the pictures of 9 species are drawn.

关键词： Hebei Province Mosses New record taihang mountain Bashang Plateau

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：