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Paleomagnetic Excursions Recorded in the Yanchi Playa in Middle Hexi Corridor, NW China Since the Last Interglacial

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Journal of Mountain Science 2004年第2期1卷 128-142页

作者： YANGTaibao YUYongtao LIJijun ANCongrong LIUJinfeng ZHANGJunyan keylaboratoryofWestern{2.Changes ChineseMinistryofEducationLanzhouUniversityLanzhou730000China DepartmentofGeography SchoolofGeosciencesNanjingNormalUniversityNanjing210097China InstituteofgeologyandGeophysics ChineseAcademyofSciencesBeo＇ing100029China

Paleomagnetic determinations on lithological profiles of two paralleled[( )-2.5(long )]drilling cores covering the past 130 kyr B.P., GT4. and GT60, from the Yanchi Playa in the arid Northwestern China, indicate that a series of pronounced paleomagnetic excursions have been documented. By correlating our results with published regional and worldwide reports, 4.excursion events out of 10 apparent reversal signals (labeled from GT-1 to GT-10) were identified as excursion events coeval with the Mono Lake Event ([(2..4.( )]kyr~[(2..8)( )]kyr), Laschamp Event ([(4..3)( )]kyr^4..5 kyr), Gaotai Event (82.8 kyr~[(72.4.2.( )]kyr) and the Blake Event (12..4.kyr^113.3 kyr), respectively. GT-9 correlates with the above-mentioned Gaotai Event, GT-7 and GT-6 correspond to two stages of the Laschamp Event and GT-5 to the Mono Lake Event. It is noteworthy that the so-called Gaotai Event has not been reported as a pronounced paleomagnetic excursion in the Northwestern China. Every magnetic excursion event corresponds to paleointensity minima, anteceding those established abrupt paleoclimatic change events, such as the Younger Drays and the Heinrich Events (H1-H6)[(. )-2.0( )]Here,[( )-2.0( )]we tentatively[( )-2.0( )]propose that these geomagnetic excursions/reversals can be viewed as precursors to climate abruptness. During the transitional stages when the earths magnetic field shifted between a temporal normal and a negative period, the earths magnetic paleointensity fell correspondingly to a pair of minima. Although more precise chronology and more convincing rock magnetic parameter determinations are essentially required for further interpretation of their intricate coupling mechanism, these results may have revealed, to some extent, that the earths incessantly changing magnetic field exerts an strong influence on the onset of saw-tooth shaped abrupt climate oscillations through certain feedback chains in arid Central Asia or even North Hemispheric high latitude regions.

关键词： Paleomagnetism geomagnetic excursion the Late Pleistocene arid Northwestern China

白垩纪-古近纪古生物地理区的变化与印度和亚洲的碰撞(英文)

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地球学报 2012年第S1期33卷 69-71页

作者： WAN Xiao-qiao,LI Guo-biao,JIANG Tian State key laboratory of {2. and {2. {4.,China University of Geosciences,Beijing 100083,China

Geologic studies of the Late Cretaceous-Paleogene stratigraphic record of southern Tibet reveal distinct episodes of collision and post-collisional *** composition of sediments exposed along the Indus-Yarlung Zangbo s... 详细信息

关键词： India-Asian collision Orbitolinids Bivalve Paleobiogeography

浙江青浜岛现代植物群落和表土植硅体研究及环境意义

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微体古生物学报 2017年第1期34卷 77-83页

作者：刘红叶顾延生唐倩倩程丹丹桂福坤中国地质大学(武汉)环境学院武汉430074 中国地质大学(武汉)生物地质与环境地质国家重点实验室武汉430074 浙江海洋大学海洋科学与技术学院

在植物分类基础上全面调查了浙江舟山青浜岛分布的植物群落类型,获得8个群丛类型,对青浜岛2.种现代植物植硅体进行提取,共鉴定出17种形态类型。帽型、齿型、哑铃型、鞍型和扇型主要见于禾本科植物;蕨类主要产波状棒型和三棱柱型;木本主... 详细信息

在植物分类基础上全面调查了浙江舟山青浜岛分布的植物群落类型,获得8个群丛类型,对青浜岛2.种现代植物植硅体进行提取,共鉴定出17种形态类型。帽型、齿型、哑铃型、鞍型和扇型主要见于禾本科植物;蕨类主要产波状棒型和三棱柱型;木本主要产纺锤型和多边形板状型,这表明不同分类位置的植物产生不同的植硅体形态及组合。对横跨整个青浜岛东南—西北坡向的8个群丛样方进行表土植硅体提取分析,共获得14.植硅体形态类型,研究结果显示表土植硅体贡献主要来自禾本科、蕨类、阔叶类和裸子类植物。随着岛屿山体海拔的增加(海拔2.—90m),示冷型和示干旱型植硅体增加,青浜岛局部生境(自东南向西北翻过山顶)气候变化表现为温暖湿润—温凉偏干—温暖湿润。表土植硅体组合灵敏地响应了海拔改变而引起的局地植被和环境的变化,是重建第四纪环境变化的可靠代用指标。

关键词：植物群落表土植硅体气候环境青浜岛浙江

environmental Redox Changes of the Ancient Sea in the Yangtze Area during the Ordo-Silurian Transition

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Environmental Redox Changes of the Ancient Sea in the Yangtz...

中国科学院地质与地球物理研究所2.08学术年会

作者： YAN Detian~(1,2.*),CHEN Daizhao~1,WANG Qingchen~1,WANG Jianguo~1 and CHU Yang~1 1 State key laboratory of Lithospheric Evolution,Institute of {2. and Geophysics,Chinese Academy of Sciences,Beijing 10002. {2. laboratory of Tectonics and Petroleum Resources,China University of Geosciences, {4. of education,wuhan 43.074

Extensive organic-matter(OM) rich facies(black shales) occur in the Ordo-Silurian boundary successions in the Yangtze area,South *** investigate the redox changes of the Yangtze Sea during the Ordo-Silurian transition,two OM sections(Wangjiawan in Yichang,Hubei Province,and Sanjiaguan in Zhangjiajie,Hunan Province) straddling the Ordo-Silurian boundary are *** measurements finished in this study include contents of the total organic carbon(TOC), pyrite sulphur,and different species of Fe,including dithionite-extractable Fe(Fe),pyrite Fe(Fe), HCl-extractable Fe(Fe),and total Fe(Fe),in black shales,as well as other redox proxies,such as the S/C ratio,the ratio between highly reactive Fe(Fe= Fe+ Fe) and Fe,and the Fe/(Fe + Fe) ratio, known as the degree of pyritization(DOP).In the Wangjiawan section,the Middle Ashgill sediments have high Fe/Fe ratios(0.2.-0.77;avg.0.4.),high DOP values(0.2.-0.72.avg.0 54.,and a relatively constant sulfur content independent of the organic carbor *** she contrast,the mid-early Hirnantian deposits generally have low Fe/Fe ratios(0.10-0.35;avg.0.2.),low DOP values(0.11- 0.4.;avg.0.2.),and S/C values are clustering on the normal marine value(S/C = 0.36).The late Hirnantian and early Rhuddanian Jeposits,similar to those of the Middle Ashgill deposits,are characterized by high Fe/Ve ratios(0.32.0.4.;avg.0.4.),high DOP values(0.4.-0.68;avg.0.53) and fairly constant sulfur mm *** data suggest the occurrences of marine anoxia on the Yangtze Sea shelf during intervals of the Mid Ashgill,Late Hirnantian and Early Rhuddanian,and ventilated and oxygenated marine conditions during the mid-early Hirnantian *** mid-early Hirnantian ventilated event was concomitant with the global glacial period,likely resulted from the glacio-eustatic sea-level fall and subsequent circulation of cold,dense oxygenated waters upon the shelf seabed. Accordingly,the abrupt change from oxygenated to anoxic marine waters from the late Hirnan

关键词： oceanic anoxia water column stratification Fe-S geochemistry organic carbon Late Ordovician Early Silurian Yangtze Sea South China

Cooling-driven climate change at 12.11 Ma:Multiproxy records from a long fluviolacustrine sequence at Guyuan,Ningxia,China

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Cooling-driven climate change at 12-11 Ma:Multiproxy records...

中国科学院地质与地球物理研究所2.08学术年会

作者： Hanchao Jiang~(a,*),Junliang Ji~b,Ling Gao~c,Zihua Tang~a,Zhongli Ding~a a key laboratory of Cenozoic {2. and Environment,Institute of {2. and Geophysics,Chinese Academy of Sciences,Beijing,10002.,China b key laboratory of {4. and environmental {2.,ministry of education,wuhan,{12.,China c Department of Geological Sciences,Indiana University,1001 East 10th Street,Bloomington,IN 4.4.5-14.5,USA

To explore the evolution of climate through the Miocene,especially during the Middle Miocene climate transition,multiproxy continental records were analyzed by susceptibility(SUS),lightness(L),total inorganic carbon(TIC) and total organic carbon(TOC) content from the 2.00-m-thick fluviolacustrine sediment sequence at Guyuan,Ningxia,China and compared with the redness(a) and the pollen humidity indices from the same *** published Miocene records of sedimentation rate,sediment grain size, biota turnover,and palaeoproductivity from other regions were also compiled and *** show that multiproxies of the Sikouzi section have changed substantially since 12.11 Ma ago,SUS,L and TIC have increased while a,TOC and the pollen humidity index decreased,all implying that the palaeoclimate in the study area has got cooler and drier since that time. This climate change also left imprints in many other regions,probably resulting from global cooling and the development of the East Antarctic Ice Sheet since about 14.*** positive feedback mechanisms are proposed to have effectively modulated and magnified the Mid-Miocene global cooling,including vegetation change,greenhouse gas(atmospheric CO and water vapor) *** led to the strengthing of ocean and atmospheric circulation,significant lowering of sea level and increasing aridification over the globe, especially in middle-high *** 12.11 Ma ago,a continuously cooler and drier climate may have caused the substantial intensification of physical weathering and exhumation on the earth’s surface,the increased sediment accumulation rates on the land and in the sea,and the inception of productivity increase in the ***,when and where these mechanisms operated and how they were tied to each other remain ambiguous,deserving further investigation.

关键词： Mid-Miocene cooling Climate change Multiproxy continental records Sikouzi Ningxia

Chemical and Strontium Isotopic Compositions of the Hanjiang Basin Rivers in China:Anthropogenic Impacts and Chemical Weathering

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Chemical and Strontium Isotopic Compositions of the Hanjiang...

中国科学院地质与地球物理研究所第11届（2.11年度）学术年会

作者： Zhifang Xu Chao Shi Yang Tang Hongyin Han key laboratory of Engineering Geomechanics,Institute of {2. and Geophysics, Chinese Academy of Sciences,10002. Beijing,China Graduate University of Chinese Academy of Sciences,10004. Beijing,China Institute of Geochemistry,Chinese Academy of Sciences,550002.Guiyang,Guizhou,China key laboratory of Biologic {2. and {4. {2. under ministry of education, China University of Geosciences,43.074 wuhan,China

The Hanjiang River,the largest tributaries of the Changjiang(Yangtze) River, is the water source area of the Middle Route of China’s South-to-North Water Transfer *** chemical and strontium isotopic compositions of the river waters are determined with the main purpose of understanding the contribution of chemical weathering processes and anthropogenic inputs on river solutes,as well as the associated CO consumption in the carbonate-dominated *** major ion compositions of the Hanjiang River waters are characterized by the dominance of Ca and HCO,followed by Mg and *** increase in TDS and major anions(Cl,NO,and SO) concentrations from upstream to downstream is ascribed to both extensive influences from agriculture and domestic activities over the Hanjiang *** chemical and Sr isotopic analyses indicate that three major weathering sources(dolomite,limestone,and silicates) contribute to the total dissolved *** contributions of the different end-members to the dissolved load are calculated with the mass balance *** calculated results show that the dissolved load is dominated by carbonates weathering,the contribution of which accounts for about 79.4.for the Hanjiang *** silicate weathering and anthropogenic contributions are approximately 12.3 and 6.87%,*** total TDS fluxes from chemical weathering calculated for the water source area(the upper Hanjiang basin) and the whole Hanjiang basin are approximately 3.8×10 and 6.1×10 ton/year,respectively. The total chemical weathering(carbonate and silicate) rate for the Hanjiang basin is approximately 38.5 ton/km/year or 18.6 mm/k year,which is higher than global mean *** fluxes of CO consumption by carbonate and silicate weathering are estimated to be 56.4.10 and 12.9×10 mol/year,respectively.

关键词： Hanjiang River South-to-North water transfer project Sr isotopic ratio Chemical weathering CO2.consumption

Research Advances on the Loess-Bedrock Landslide in China

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Research Advances on the Loess-Bedrock Landslide in China

2.12.Asia Pacific Conference on environmental Science and Technology(APEST 2.12.

作者： Chengyi Fan1 a Shouyun Liang1 b and Xiangxian Ma2.c 1 key laboratory of Mechanics on Disaster and Environment in Western China the {2. of {4. of China and Department of Geological Engineering College of Civil Engineering and Mechanics Lanzhou University Lanzhou 730000 P.R.China 2.key laboratory of Petroleum Resources Research Institute of geology and Geophysics Chinese Academy of Sciences Lanzhou 730000 P.R.China

Loess landslide is one of the serious geological disasters in and around the loess plateau in northwest of *** the major type of loess landslide in this area,loess-bedrock landslide widely distributes,frequently occurs,and causes serious casualties and property *** the formation mechanism and protection countermeasures arousing increasingly,the scientists have paid close attention and got a series of research *** is very important of systematic summary and thorough analysis of the loess-bedrock landslide for reducing disasters caused by loess *** acquired achievements of the loess-bedrock landslide have been summarized on classification,formation mechanism,influencing factors and hazard range,and some main fields are put forward for further researching:（1） to explore the control action and boundary effect of paleo-weathering crust upon the top of bedrock for the loess-bedrock landslide;（2. to research the influence of the orientation and the top fluctuant configuration of bedrock and the slope structure on loess landslide;（3） to study the relationship between the landslide formation and the slope profile structure,the physical,hydrological and mechanical properties of the rock-soil mass;（4. to research the critical value of locked segment in the loess-bedrock cutting layer landslide;（5） to analyze the main influencing factors and forecast the hazard range of different types of the loess-bedrock landslide.

关键词： Loess-bedrock landslide Landslide classification Formation mechanism Hazard range Research advances.

Contribution of Safety to Economic Growth:A case study of China Mining Industry

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Contribution of Safety to Economic Growth:A case study of Ch...

2.11 Chinese Control and Decision Conference（CCDC）

作者： TAN Haixia1,WANG Hongtu1,WANG Zaiqing2.CHEN Lin3,REN Huanlin4.1.key Lab for Exploitation of China Southwestern Resources & environmental Disaster Control Engineering,{2. of {4.,Chongqing University,Chongqing 4.0030,China2.Institute of Chongqing geology and Mineral Resources,Chongqing 4.0030,China3.Exploration Institute of geology and Mineral Resources,Yunnan Bureau of geology and Mineral Resources,Kunming 650051,China4.College of History and Sociology,Huaibei Normal University,Huaibei 2.5000,China

Safety input is a way of safeguarding mining,as well as one of main reasons for the increased growth rates of Total Factor Productivity （TFP）.To figure out the contribution of the safety input to mining economic growth,a new production safety index system with six principal items describing China mining safety was *** study found that China mining production safety level was improved continuously,a more than 17-fold increase from 1991 to *** co-integration theory and dynamic construction model,a mining economic growth model was established based on the new production safety index *** empirical results prove that labor input and capital input are still major factors of promoting mining economic growth,and the production safety not only contributed the short-term GDP growth of mining industry but also helped present 8.8% of contribution rate to the long-term elasticity coefficient.

关键词： Mining industry production safety index economic growth model contribution rate of safety input to economy growth

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舟山北部海域海底淡水资源研究现状

海洋地质前沿 2012年第8期28卷 43-48页

作者：韩月张志忠何兵寿中国海洋大学海底科学与探测技术教育部重点实验室青岛266100 青岛海洋地质研究所青岛266071 国土资源部海洋油气资源与环境地质重点实验室青岛266071

近海海底第四纪淡水资源主要赋存在相对比较封闭的古河道砂体地层环境中,埋藏古河道分布是海底淡水资源的研究重点。介绍了我国舟山北部海域海底淡水资源初步研究成果,在综合前人研究成果的基础上,指出了海底淡水资源调查研究中存在的问... 详细信息

近海海底第四纪淡水资源主要赋存在相对比较封闭的古河道砂体地层环境中,埋藏古河道分布是海底淡水资源的研究重点。介绍了我国舟山北部海域海底淡水资源初步研究成果,在综合前人研究成果的基础上,指出了海底淡水资源调查研究中存在的问题,对未来工作提出了展望。

关键词：近海海域海底淡水资源赋存条件埋藏古河道