检索结果-南通市图书馆

Isotopic compositions of small shelly fossil Anabarites from Lower Cambrian in Yangtze Platform of South china: Implications for palaeocean temperature

引用

Progress in Natural Science:Materials International 2007年第10期17卷 1185-1191页

作者： Chen Yongquan1,2, Jiang Shaoyong1, Ling Hongfei1, Yang Jinghong1 and Wan Defan3(1. State Key Laboatory for Mineral Deposits Research and Center for Marine Geochemistry Research, Department of Earth sciences, Nanjing University, Nanjing 210093, china 2. Tarim Oilfield Company Exploration & Development Research institute, Ku’erle 841000, china 3. institute of Mineral Resources, Chinese Academy of geological sciences, Beijing 100037, china) State Key Laboatory for Mineral Deposits Research and Center for Marine Geochemistry Research Department of Earth Sciences Nanjing University Nanjing 210093 China arim Oilfield Company Exploration & Development Research institute Ku’erle 841000 China institute of Mineral Resources Chinese Academy of Geological Sciences Beijing 100037 China

Anabarites belong to small shelly fossils (SSF), which occur widely in the Lower Cambrian strata of Yangtze Platform in South china. They are phosphate shell in composition and represent the earliest stage of the Cambrian bioradiation of Bilateria, the so-called "Cambrian Explosion". In this study, we attempted to separate Anabarites fossils from Lower Cambrian dolostones, and we obtained samples of both the fossils (SSF) and the granular phosphates (GP). Isotopic analyses were performed on samples of SSF, GP, and matrix dolostone (DH-23). The results showed that the δ30Si values of the quartz filling in fossils celoms, and the siliceous materials in granular phosphates are -0.6‰ and -0.7‰, which is different from normal sedimentary siliceous rocks from the Lower Cambrian strata (0—0.7‰) as reported by Li et al., but is consistent with the data for siliceous rocks and cherts of submarine hydrothermal origin. It is likely that a later hydrothermal replacement could have taken place in the SSF-bearing sedimentary rocks. The oxygen isotope values of the phosphate of SSF and GP are 16.8‰ and 17.0‰, respectively. These are significantly higher than the Neoproterozoic phosphate ores (10.9‰—13.9‰) as reported by Ling et al., hence, late diagenesis and hydrothermal replacement may not have caused a significant change in the oxygen isotope compositions of the small shelly fossils, and the calculated temperatures (25.4—26.3℃) for palaeo-seawater using a SSF phosphate oxygen isotope thermometer are therefore considered here as the upper limit of seawater temperature in the Early Cambrian ocean of the Yangtze Platform.

关键词： Anabarites oxygen isotope silicon isotope paleo-temperature.

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Medusoid Fossils from the Sinian Xingmincun Formation of Southern Liaoning province

引用

Acta Geologica Sinica(English Edition) 1989年第1期63卷 11-22,103-104页

作者： Hong Zuomin, Huang Zhenfu, Yang Xinde, Lan Jing, Xian Bingcai, Yang Yajun, Regional geological Survey Party, Bureau of Geology and Mineral Resources of Liaoning province, Jinzhou, Liaoning and Liu Xiaoliang Shenyang institute of Geology and Resources, Chinese Academy of geological sciences, Shenyang, Liaoning Fang Xinzhong BUR GEOL & MINERAL RESOURCES LIAONING province REG GEOL SURVEY PARTY JINZHOU PEOPLES R CHINA CHINESE ACAD GEOL SCI SHENYANG INST GEOL & RESOURCES SHENYANG PEOPLES R CHINA

Abundant medusoid soft-bodied metazoan fossils have been found in the Sinian Xingmincun Formation(with an isotopic age of 650 Ma) at Qipanmo, Qidingshan and Yangtun of the Dalian-Jinzhou area, southern Liaoning province; in addition, a number of macroscopic algal fossils have been discovered for the first time in the Getun Formation overlying the Xingmincun Formation. Medusoid fossils include 3 genera and 6 species(all of which are new). Judging from their biological characters, these medusoid fossils are considered to have an intimate affinity with the Ediacara fauna in the terminal Precambrian of Australia, as their characters are close to each other. The authors suggest that these medusoids and the Edicara fauna might be the products of the same period. The discovery of the medusoid fauna in the Xingmincun Formation marks an important event in the evolution of the terminal Precambrian organisms in china, and it is of major practical significance in the study of the Sinian System of china and the correlation of the Sinian strata of northern and southern china.

关键词： Medusoid Fossils from the Sinian Xingmincun Formation of Southern Liaoning 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

Late Carboniferous-Early Permian Volcanic Event Deposits and Stratigraphic Correlation in Shandong province and Its Adjacent Regions

引用

Acta Geologica Sinica(English Edition) 1996年第4期70卷 380-394,453页

作者： Zhong Rong, institute of Geomechanics, Chinese Academy of geological sciences, BeijingSun Shanping and Fu Zeming china University of Geosciences, Beijing Xu Niansheng, Xu Heling and Zhong Rong

Deposits of 10 volcanic events of 6 stages have been discovered by the authors after detailed field and lab studies of the Benxi and Taiyuan Formations in Shandong province and its adjacent regions. They show certain temporal-spatial distribution characteristics. Volcanic fragments were probably derived from two different volcanic sources north and south of the North china Platform, while the magma of the two volcanic sources was probably derived from the lower crust. A new stratigraphic correlation scheme is put forward for the Benxi and Taiyuan Formations in this region on the basis of previous biostratigraphic work with the regionally widespread volcanic event layers as the marker bed for the isochronous stratigraphic correlation on a super-regional scale and in conjunction with the maximum transgressive event layers.

关键词： volcanic event deposits Late Carboniferous-Early Permian Benxi and Taiyuan Formations stratigraphic correlation volcanic source Shandong province and its adjacent regions

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

A sort of iron-manganese nodule developing in drowned platform margin

引用

Chinese Science Bulletin 1999年第S2期44卷 34-35页

作者： JIANG Yuehua, YE Zhizheng and YUE Wenzhe Nanjing institute of Geology and Mineral Resources, Chinese Academy of geological sciences, Nanjing 210016, china Nanjing institute of Geology and Mineral Resources Chinese Academy of Geological Sciences Nanjing 210016 China

A sort of purplish red iron-manganese nodules was found in the Middle Ordovician Guniutan-Miaopu period limestone, Anhui province. About their formational environment, there are two different viewpoints:Yue thought they were deep-water pelagic deposit and Huang et al. believed they were formed inshallow water tide. We think that these nodules were formed in drowned platform margin belonging to atransitional type between shallow-water and deep-water iron-manganese nodules, and different from shoalwater iron-manganese oolites and pelagic iron-manganese nodules in feature and origin. 1 Palaeogeographic setting of iron-manganese nodules

关键词： iron-manganese nodule drowned platform platform margin.

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

REE Geochemistry in the Weathered Crust of Granites, Longnan Area,Jiangxi province

引用

Acta Geologica Sinica(English Edition) 1990年第2期64卷 193-209,237页

作者： Wu Chengyu Huang Dianhao Guo Zhongxun institute of Mineral Deposits, Chinese Academy of geological sciences, Beijing geological Survey Party of South Jiangxi, Jiangxi Bureau of Geology and Mineral Resources, Ganzhou, Jiangxi JIANGXI BUR GEOL & MINERAL RESOURCES GEOL SURVEY PARTY S JIANGXIGANZHOUPEOPLES R CHINA

Warm and humid climate and gentle hilly topography have provided favourable conditions for the devel-opment of the weathering crust of the granite intrusions in the Longnan area, Jiangxi province. REE is mostlyconcentrated in an adsorption state in clay in the wholly weathered zone. The rare-earth minerals enriched inthe parent rocks provided the source material for the REE enrichment. Exchangeable REE accounts for48-86%. Extraction experiments and stable isotopic study of clay minerals suggest that the downward infiltra-tion of meteoric water and increasing gradient of pH values have played an important role in the enrichment ofREE during the progressive weathering. Slight fractionation of individual REE can not change their distribu-tion patterns in the profiles. which are inherited from the parent rocks.

关键词： REE Geochemistry in the Weathered Crust of Granites Longnan Area,Jiangxi 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

Characteristics and Zonation of the Cenozoic Volcanic Rocks on the Qinghai-Tibet Plateau

引用

Continental Dynamics 1997年第1期 1-11页

作者： YANG Jingsui XU Zhiqin BAI Wenji (institute of Geology, Chinese Academy of geological sciences, Beijing 100037, china) ZHAO Rough (geological Survey of Qinghai province, Xining 810001, china)

The Cenozoic volcanic rocks on the Qinghai-Tibet plateau are recognized as four zones in space and time, i.e., the North Tertiary Zone （NTZ）, the North Quaternary Zone （NQZ）, the South Zone （SZ）, and the East Zone （EZ）, based on this and previous studies. Petrological and geochemical results show that in the four zones intermediate-acid volcanic rocks are prominent, and basic-intermediate and acid are subordinate. The rocks are characterized by high contents of K2O + Na2O （about 8 wt%）, and K2O/Na2O > 1 or close to 1, and mostly belonged to shoshonite-trachyte association and some to ultra-potassic rocks, showing affinity of orogenic genesis. Sr, Nd and Ph isotopic studies suggest that the majority of volcanic rocks were originated from the lower crush and minor, basic rocks from enriched mantle. The volcanic activity started from Paleocene, much earlier than the continent-continent collision and intercontinental subduction at the Himalayan front that started most likely from Miocene. The volcanic activities were mainly constrained by deep-seated faults which cut through the lower crust and into the mantle. That the volcanic rocks are distributed in the interior of the plateau as well as at its margin also suggests that plate subduction and collision is not the merely factor for the genesis of these rocks.

关键词： Cenozoic volcanic rocks shoshonite trachyte Qinghai-Tibet plateau

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

UNSTEADY FLOW OF NON-NEWTONIAN VISCO-ELASTIC FLUID IN DUAL-POROSITY MEDIA WITH THE FRACTIONAL DERIVATIVE

引用

Journal of Hydrodynamics 2009年第5期21卷 705-713页

作者： SHAN Lian-tao TONG Deng-ke XUE Li-li School of Petroleum Engineering China University of Petroleum Dongying 257061 China Research institute of geological sciences Shengli Oilfield Company Sinopec Dongying 257015 School of Mathematics and Computational sciences China University of Petroleum Dongying 257061 China

The fractional order derivative was introduced to the seepage flow research to establish the relaxation models of non-Newtonian viscoelastic fluids in dual porous media. The flow characteristics of non-Newtonian viscoelastic fluids through a dual porous medium were studied by using the Hankel transform, the discrete Laplace transform of sequential fractional derivatives and the generalized Mittag-Leffler function. Exact solutions were obtained for arbitrary fractional order derivative. The long-time and short-time asymptotic solutions for an infinite formation were also resulted. The pressure transient behavior of non-Newtonian viscoelastic fluids flow through an infinite dual porous media was studied by using Stehfest＇s inversion method of the numerical Laplace transform. It shows that the characteristics of the fluid flow are appreciably affected by the order of the fractional derivative.

关键词： fractional calculus non-Newtonian visco-elastic fluids dual porous media exact solution

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

Allelic frequency distributions of 21 non-combined DNA index system STR loci in a Russian ethnic minority group from Inner Mongolia,china

引用

Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2013年第6期14卷 533-540页

作者： Hong-dan WANG Chun-mei SHEN Wen-juan LIU Yu-dang ZHANG Guang YANG Jiang-wei YAN Hai-xia QIN Bo-feng ZHU School of Medicine Xi'an Jiaotong University People's Hospital of zhengzhou University Medical Genetic institute of henan province People's Hospital of Henan Province Blood Center of Shaanxi province Vascular Biology Center Georgia Health Sciences UniversityAugustaGA 30912USA Beijing institute of Genomics Chinese Academy of Science Department of Internal Medicine Morehouse School of MedicineAtlantaGA 30303USA

We studied the allelic frequency distributions and statistical forensic parameters of 21 new short tandem repeat(STR)loci and the amelogenin locus,which are not included in the combined DNA index system(CODIS),in a Russian ethnic minority group from the Inner Mongolia Autonomous Region,china.A total of 114 bloodstain samples from unrelated individuals were extracted and co-amplified with four fluorescence-labeled primers in a multiplex polymerase chain reaction(PCR)*** capillary electrophoresis,the PCR products of the 21 STR loci were separated and genotyped.A total of 161 alleles were observed in the Russian ethnic minority group,and corresponding allelic frequencies ranged from 0.0044 to *** 21 non-CODIS STR loci of the Russian ethnic minority group were characterized by high genetic diversity and therefore may be useful for elucidating the population's genetic background,for individual identification,and for paternity testing in forensic practice.

关键词： Short tandem repeat(STR) Russian population Genetic polymorphisms

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

Northernmost paleo-tethyan oceanic basin in Tibet:Geo-chronological evidence from ^(40)Ar/^(39)Ar age dating of Dur'ngoi ophiolite

引用

Chinese Science Bulletin 2001年第14期46卷 1203-1205页

作者： CHEN Liang, SUN Yong, PEI Xianzhi, GAO Ming, FENG Tao, ZHANG Zhongqing & CHEN Wen1. Laboratory of Continental Dynamics, Northwest University, Xi’an 710069, china 2. Department of Geology, Northwest University, Xi’an, 710069, china 3. institute of Geology, Chinese Academy of geological sciences, Beijing, 100037, china Laboratory of Continental Dynamics Northwest University Xi’an China Department of Geology Northwest University Xi’an China institute of Geology Chinese Academy of Geological Sciences Beijing China

Whole rock 40Ar/39Ar age dating has been conducted on a basalt sample from Dur’ngoi ophiolite, Qinghai province, which was reported to be the northernmost pa-leo-tethyan oceanic basin in Tibet. A high temperature pla-teau age (345.3±7.9 Ma) with an isochorn age (336.6±7.1 Ma) has been obtained, representing the eruption time of oceanic crust Considering related geological settings, the new age provides constraints on the northernmost pa-leo-tethyan suture zone in Tibet and the tectonic evolution of Paleo-tethys in Northeast Tibet and adjacent areas.

关键词： Dur’ngoi ophlolite 40Ar -39Ar age Paleo-tethys.

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

Study on the changes of water cycle and its impacts in the source region of the Yellow River

引用

Science china(Technological sciences) 2004年第z1期47卷 142-151页

作者： ZHANG Shifeng1, JIA Shaofeng1, LIU Changming1, CAO Wenbing2, HAO Fanghua3, LIU Jiuyu4 & YAN Huayun5 1. institute of Geographic sciences and Natural Resources Research, Chinese Academy of sciences, Beijing 100101, china 2. china University of Geosciences, Beijing 100083, china 3. Beijing Normal University, Beijing 100875, china 4. Bureau of Hydrology of Yellow River Conservancy Commission, zhengzhou 450003, china 5. Bureau of Hydrology and Water Resource Investigation of Qinghai province, Xining 810001, china 1. institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China2. China University of Geosciences 100083 Beijing China3. Beijing Normal University 100875 Beijing China4. Bureau of Hydrology of Yellow River Conservancy Commission 450003 Zhengzhou China5. Bureau of Hydrology and Water Resource Investigation of Qinghai Province 810001 Xining China

The water cycle in the source region of the Yellow River underwent great changes in the 1990s. The major features of the changes are as follows: the gauged runoff declined significantly while the precipitation increased slightly, and the runoff process was more concentrated on the flood season. Water balance analyses indicate that the pondage was kept in the status of negative equilibrium, causing eco-environmental problems. The runoff decrement is due to evaporation increment in this region. Studies show that the runoff process in this region is closely related to that of the other hydrological stations in the upper reaches. When the runoff declines in the source regions, the amount of water also declines in the whole upper reaches of the Yellow River, affecting the balance between water demand and supply. Meanwhile changes will take place in the water cycle of the river course system when the eco-environment deteriorates. The trend of water cycle change in the source region is that the runoff will keep declining with the increment of evaporation caused by temperature rise in the northwest of china in the 21st century. But the hydraulic engineering in the source region will help to mitigate the deterioration of local eco-environment system, though the impacts to the lower reaches of this project may not be the case.

关键词： source region of the Yellow River, water cycle, evaporation, negative equilibrium.

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

在线全文

在线全文

在线全文

在线全文

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

在线全文

在线全文

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：