检索结果-南通市图书馆

Late Glacial and Holocene vegetation history and paleoclimate of the Tengger Desert,northwestern China

Chinese Science bulletin 2003年第14期48卷 1457-1463页

作者： MAYuzhen ZHANGHucai H.-J.Pachui b.wtinnemann LIJijun FENGZhaodong NationalLaboratoryofWesternChina'sEnvironmentalSystems CollegeofEarth&EnvironmentSciencesLanzhouUniversityLan-zhou730000China Geolab. InstituteofGeographicalSciencesFreeUniversityofBerlinMalteserStr.74-10012249Berlin.Germany DepartmentofEarthandEnvironmentalStudies MontclairstateUni-versityNJ07043USA

Sediments spanning the last 30000 yr bP wereobtained from two sections in the southern part of the Teng-ger Desert, northwestern China (3810′46″N, 10245′53″E). The pollen assemblage suggested a Picea forest domination under a wetter and cooler environment from 27580 to 23510 yr bP. During the following period from 23510 to 21880 yr bP a Cyperaceae meadow occurred under a wet and coldclimate. Wetter and cooler conditions returned and a Piceaforest re-occupied this region between 21880 and 20910 yrbP. From 20910 to 15590 yr bP a steppe under a dryenvironment dominated the region. The first temperatureincrease started at ca.15590 yr bP. The pollen assemblagecovering the period between 15590 and 10890 yr bP can be divided into six minor zones, suggesting that the vegetation compositions changed rapidly under unstable *** 10710 and 10370 yr bP the climate became cold and dry again. The climatic conditions became warmer and more humid between 10260 and 9140 yr bP. From 8450 to 7950 yr bP a steppe landscape under a dry climate occupied this region. between 7950 and 7290 yr bP climate seemed more humid. The following period from 7290 to 5670 yr bP wasgenerally warm. The period between 5670 and 3510 yr bPwas characterized by dramatic climatic *** cold intervals appeared around 7760 and 7380,6490—6290, 5670—5010, 4470—3510 yr bP. Twopronounced dry events occurred in 6290—5670 and 5010—4470 yr bP with a marked wet spell from 3510 to 3000 yr bP.

关键词：中国西北地区腾葛尔沙漠古气候全新世晚冰期古植被孢粉学

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

EVIDENCE OF NEOTECTONIC IMPACT ON A LARGE SEDIMENTARY bASIN bETWEEN TIbETAN PLATEAU AND GObI ALTAY,NW CHINA

引用

第四纪研究 2009年第4期29卷 687-695页

作者： K. Hartmann b. wtinnemann Hucai Zhang Department of Earth Sciences Freie Universitat Berlin Malteserstrraβe 74 - 100 12249 Berlin Germany State Key Laboratoryof Lake Science and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China

The Ejina( Gaxun Nur) basin-enclosed by the Tibetan Plateau in the south and the Gobi Altay in the north hascontinuously evolved as a strong continental endorheic depositional environment. Medium scale geomorphological mappingby Landsat- and Corona-Images as well as SRTM-topographic data, combined with field-surveys and geophysicalinvestigation provides evidence for tectonic impact on sedimentary processes during the Late *** of SRTM-Data and Landsat-Images reveal a system of up to 20m high inverted channels developed on theinactive eastern part of the large Hei river drainage delta south of the ancient lake Juyanze. The complex evolution of theselandforms requires a relative lowering of the lake basin at least two times since the last 40ka. A 26m high cliff section ofgravel-covered lake sediments within the Juyanze paleolake indicates a strong subsidence of the lake bottom of 10m/1000yrssince 18kab. *** of Ejina river oasis a distinct north-south striking scarp up to 13m high constitutes the eastern margin of theGaxun Nur. Palaeodrainage channels derived from the Gobi Altay. They display a sinistral offset of some decametres alonga set of WE-trending faults. The rhombic shape of the modern dry Gaxun Nur, fossil cliffs,well preserved beach ridges alongthe margins of the palaeolake system as well as gravel covered topsets of lacustrine sediments indicate local displacements ofmorphological features. The displacements of lake sediments at the southern margin of the modern Gaxun Nur basin imply asubsidence of at least 0.81m/1000 yrs since 25kab. P. as a result of a pull-apart development due to the left stepping faultsin a sinistral system.

关键词：西藏高原第四纪地质结构湖泊

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

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

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

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：