检索结果-南通市图书馆

Early-Middle Permian Reef Frameworks and Reef-building Models in the Eastern Kunlun Mountains

Acta Geologica Sinica(English Edition) 2001年第2期75卷 115-125页

作者： TIAN Shugang institute of Geology, chinese academy of {3. Sciences,{4.and FAN Jiasong institute of Geology and Geophysics, chinese academy of Sciences, beijing 100029 institute of Geology Chinese Academy of Geological Sciences Beijing 100037 institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 [?]3.ian Shugang Born in September 1951 graduated from beijing University in 1977 and received his MS. and Ph. D. degrees at china University of Geosciences (beijing) in 1985 and 1988 respectively working now in the institute of Geology Chinese Academy of Geological Sciences. He has long been engaged mainly in studies of biostratigraphy palaeoecology sequence-stratigraphy and reefs. Tel: 010–68328223 E-Mail: sgtian2001@***

Reef frameworks and building models of the Early-Middle Permian in the eastern Kunlun Mountains have been verified through studies of reef-building communities, palaeoecology and carbonate facies. The eastern Kunlun reefs are built mainly by 6 reef-building communities, which include 11 major categories of frame-building organisms and 6 categories of reef-associated organisms. Eight types of reef-frames have been distinguished and eleven kinds of rocks identified to belong to 6 reef facies. Three sorts of reefs classified by previous researchers, namely mudmounds, knoll reefs and walled reefs, are well developed in the study area. Such reef-facies association and reef distribution show that there are 4.models of reef growth and development, i.e. the tidal-bank knoll-reef model, the plateau-margin wall-reef model, the composite wall-reef model and the deep-water mudmound model. The reefs are mainly constructed by calcareous sponge and calcareous algae, which are similar to all Permian reefs in other area

关键词： reef model Early-Middle Permian eastern Kunlun reefs

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

Grain-size features of a Miocene loess-soil sequence at Qinan: Implications on its origin

引用

Science china Earth Sciences 2006年第7期49卷 731-738页

作者： QIAO Yansong1,3. GUO Zhengtang2,1, HAO Qingzhen1, YIN Qiuzhen1, YUAN Baoyin1 & LIU Tungsheng1 1. institute of Geology and Geophysics, chinese academy of Sciences, {3. 100029, china 2. institute of Earth Environment, chinese academy of Sciences, Xi’an 710075, china 3. institute of Geomechanics, chinese academy of {14. Sciences, {3. 100081, china 1. institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 3. institute of Geomechanics Chinese Academy of Geological Sciences Beijing 100081 China 2. institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China

In this study, grain-size of 507 bulk samples from the QA-I Mioceneloess-soil sequence at Qinan were analyzed, and the grain-size features are compared with those oftypical Quaternary loess and soil samples, representative lacustrine and fluvial samples. Theresults indicate that the grain-size distribution pattern of the Miocene loess is essentiallysimilar to that of Quaternary loess, but greatly differs from the lacustrine and fluvial *** layers are regularly coarser than soil layers, indicating cyclical climate changes. Mediangrain-size along the 253.1 m sequence varies from 6 to 13.μm and the > 63.μm fraction representsonly 5.3. in maximum, 0.9% in average. Long-term grain-size variations are consistent with the loessaccumulation rate at Qinan and with the eolian mass accumulation rate in the North Pacific. Thesefeatures firmly indicate an eolian origin of the studied sequence, and also reveal a coeval changesbetween the long-term changes of eolian grain-size and continental aridity in the dust sourceregions.

关键词： Qinan, Miocene loess-soil sequence, grain-size, eolian origin.

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

An improved method for evaluating the seasonal variability of total suspended sediment flux field in the Yellow and East china Seas

引用

International Journal of Sediment Research 2011年第1期26卷 1-14页

The suspended sediment flux field in the Yellow and East china Seas(YECS) displays its seasonal variability.A new method is introduced in this paper to obtain the flux field via retrieval of ocean color remote sensing data,statistical analysis of historical suspended sediment concentration data,and numerical simulation of three-dimensional(3.) flow *** components of the sediment flux field include(i) surface suspended sediment concentration inverted from ocean color remote sensing data;(ii) vertical distribution of suspended sediment concentration obtained by statistical analysis of historical observation data;and(iii) 3. flow field modeled by a numerical *** the improved method,the 3. suspended sediment flux field in the YECS has been *** comparison with the suspended sediment flux field solely based on the numerical simulation of a suspended sediment transport model,the suspended sediment flux field obtained by the improved method is found to be more *** 3. suspended sediment flux field from ocean colour remote sensing and in situ observation are more closer to the ***,by quantitatively analyzing the newly obtained suspended sediment flux field,the quantity of sediment erosion and deposition within the different regions can be *** sediment exchange between the Yellow Sea and the East china Sea can be *** mechanism of suspended sediment transport in the YECS can be better *** particular,it is suggested that the long-term transport of suspended sediment is controlled mainly by the circulation pattern,especially the current in winter.

关键词： Suspended sediment flux field Seasonal variability Yellow and East china Seas Regression equation Numerical simulation

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

Northernmost paleo-tethyan oceanic basin in Tibet:Geo-chronological evidence from ^(4.)Ar/^(3.)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, {3. 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 4.Ar/3.Ar 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 (3.5.3.7.9 Ma) with an isochorn age (3.6.6±7.1 Ma) has been obtained, representing the eruption time of oceanic crust Considering related {4. 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 4.Ar -3.Ar 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

Development of Zr/ZrO_2 high temperature and high pressure sensors for in-situ measuring chemical parameters of deep-sea water

引用

Science china(Technological Sciences) 2009年第8期52卷 2466-2473页

作者： ZHANG XueTong, ZHANG RongHua, HU ShuMin & WANG Yong Open Research Laboratory of Geochemical Kinetics, institute of Mineral resources, chinese {3. of {4. Sciences, beijing 100037, china Open Research Laboratory of Geochemical Kinetics Institute of Mineral Resources Chinese Academy of Geological Sciences Beijing 100037 China

In order to in situ measure chemical parameters of deep-sea water and hydrothermal fluids at midocean ridge(MOR), it is necessary to use high temperature and high pressure chemical *** new sensors is essential to measure in-situ pH and other chemical parameters(dissolved H2, dissolved H2S) of deep-sea water and hydrothermal fluids in a wide temperature range(2℃―4.0℃) at MOR *** YSZ(Yttria Stabilized Zirconia, 9%Y2O3. ceramic-based(HgO/Hg) chemical sensors possess excellent electrochemical properties at high temperatures, which have been used to measure chemical parameters of hydrothermal fluids above 200℃.A novel Zr/ZrO2 oxidation/reduction electrode was constructed by oxidation of Zr wire in Na2CO3.*** Zr/ZrO2 electrode has good chemical stability while measuring pH of high-temperature aqueous solutions, combined with a Ag/AgCl reference *** of the Zr/ZrO2 sensor in association with a Ag/AgCl reference electrode vary linearly with pH over a wide pH range, as tested by various NaCl-HCl-H2O solutions(NaOH-NaCl-H2O for basic solutions), at temperatures in the range of 20℃―200℃.Thus, the Zr/ZrO2 sensors can be utilized in monitoring the fluids over the temperature range of 2℃―200℃.The Zr/ZrO2 electrode combined with Ag/AgCl, Ag/Ag2S, and Au electrodes has been used to measure pH and other chemical parameters(dissolved H2, dissolved H2S) of aqueous fluids from low to high temperatures and high pressures in the laboratory and to monitor those parameters of deep-sea water in South china Sea.

关键词： Zr/ZrO2 sensor melt oxidation method high temperature and high pressure chemical parameters investigation in the deep ocean

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

Ages and Compositions of the Precambrian High-grade Basement of the Qilian Terrane and Its Adjacent Areas

引用

Acta Geologica Sinica(English Edition) 2001年第4期75卷 375-384页

作者： WAN Yusheng, XU Zhiqin, YANG Jingsui and ZHANG Jianxin institute of Geology, chinese academy of {3. Sciences,{4. institute of Geology Chinese Academy of Geological Sciences Beijing 100037 [?]2Wan Yusheng Born in 1958 graduated from china University of Geosciences in 1981 received the Ph.D. degree in 1993 now senior geologist at the institute of Geology Chinese Academy of Geological Sciences engaged in the study of geochemistry. Tel: 010–683.84.1 e-mail: wanysh@***

Based on geological, chronological, geochemical and Nd isotopic studies of the high-grade basement of the Qilian terrane, the authors have drawn the following main conclusions: (1) the high-grade basement of the Qilian terrane consists mainly of meta-argillo-arenaceous rocks and granites and its bulk part was formed in the period of 0.8–1.0 Ga (the Jinningian period); (2) most of the meta-argillo-arenaceous rocks and granitic rocks have strong negative Eu and Ba anomalies (Eu/Eu*= 0.4.–0.71 and Ba/Ba*=0.16–0.64., with fDM and ENd (1.0 Ga) ranging from 1.87 to 2.26 Ga and from ?8.54.to ?4.06 respectively, showing relatively high maturity; and (3. the Jinningian granitic rocks are a typical product of continent-continent collision, being probably related to the formation of the supercontinent Rodinia. These studies, combined with the study of high-grade basement rocks near the Qilian terrane, suggest that before the Jinningian period, the Qilian-Qaidam northern-margin terrane and Dunhuang-Alxa terrane were separated from each other, belonging to different plate systems of the North china craton and Yangtze platform respectively. The Qilian orogenic belt was the same as or similar to the Qiling orogenic belt in terms of the geological evolution history at least before the Jinningian period.

关键词： Qilian terrane chronology Nd isotope geochemistry Precambrian basement

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

Petrogenesis and dating of the Kangding complex,Sichuan Province

引用

Science china Earth Sciences 2005年第5期48卷 622-634页

作者： CHEN Yuelong 1 , LUO Zhaohua 1 , ZHAO Junxiang, LI Zhihong, ZHANG Hongfei & SONG Biao 3.1. Faculty of Earth Sciences and Natural resources, china University of Geosciences, beijing 100083. china 2. Faculty of Earth Sciences, china University of Geosciences, Wuhan 4.0}074. china 3. beijing SHRIMP Center, institute of Geology, chinese academy of {14. Sciences, beijing 100037, china 1. Faculty of Earth Sciences and Natural resources China University of Geosciences 100083 Beijing China 2. Faculty of Earth Sciences China University of Geosciences 430074 Wuhan China 3. beijing SHRIMP Center Institute of Geology Chinese Academy of Geological Sciences 100037 Beijing China

An analysis of major and trace element geochemistry and SHRIMP U-Pb zircon dating of mafic, intermediate, and felsic rocks from the Mianning metamorphic complex of Si- chuan Province was conducted. One of our conclusions is that a majority of the zircons crystal- lized between 721 and 773.Ma in a magmatic regime. The complexes contain early to late Pa- leo-proterozoic relict zircons from ancient continental crust. The oldest age, 24.8 Ma, may rep- resent the basement of the Yangtze block. Overgrowth zircon rims and palingenetic zircons have been observed and dated, and are believed to have formed after crystallization, during Paleozoic and Mesozoic metamorphic-anatexis. We also conclude that depletion of Nb, Ta, HREE, in a spider-diagram normalized to primitive mantle and calc-alkaline association, implies that they formed in island-arc or under-plating settings.

关键词： Kangding complex, zircons, SHRIMP, tectonic setting.

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 Study of Mesoproterozoic Iron Cosmic Micro-spherules from 1.8 Ga and 1.6 Ga Old Strata in the Ming Tombs District,beijing

引用

Acta Geologica Sinica(English Edition) 2007年第4期81卷 649-657页

作者： SONG Tianrui HE Zhengjun WAN Yusheng and LIU Yanxue institute of Geology,chinese academy of {3. Sciences,{4. 100037 institute of Geology Chinese Academy of Geological Sciences Beijing 100037

Numerous iron cosmic micro-spherules have been discovered from Mesoproterozoic strata including the Changzhougou Formation （1.8 Ga） and the Dahongyu Formation （1.6 Ga） of the Ming Tombs district, beijing. There are 1 to 3. grains of cosmic spherules per 2 kg of a sandstone sample taken from the bottom of a coarse sandstone bed of the Changzhougou Formation and 56 grains per 3.69 kg of a rock sample from silicified carbonate rocks of the Dahongyu Formation. The surface textures of cosmic spherules analyzed by means of the secondary electron imagery are identical with those reported from references either domestic or abroad. So far the geo-ages of 1.8 Ga and 1.6 Ga of cosmic spherules from the Changzhougou and Dahongyu formations might be older than those reported in the world. Table 1 gives the electron probe analysis data of cosmic spherules for 3. spherule grains and 4. testing points as follows （%）： FeO, 80-95; Cr2O3. 0-9.56; NiO, 0-0.78; CoO, 0-0.4.; indicating that the Cr2O3.content is higher and FeO content lower in the Changzhougou Formation than in the Dahongyu Formation. The helium isotopic data of cosmic spherules as well as their host rocks vary greatly between the Changzhougou and the Dahongyu formations as shown in Table 2. The data of cosmic spherules of the Changzhougou Formation vs the Dahongyu Formation are 57.5/1.23.in ^3.e/^4.e （10^-8）; and 55.54.809.60 in ^4.e （10^-6cm^3.TP/g）; those of coarse sandstone of the Changzhougou Formation vs silicified carbonate of the Dahongyu Formation are 3.3./2.59 in ^3.e/^4.e （10^-8） and 4.56/2.3. in ^3.e （10^-6cm^3.TP/g）. The ratio of analytic data of helium isotopes are different for cosmic spherules and their host rocks; for example, the ^3.e/^4.e （10^-8） values are 16.96 and 0.4., and the ^4.e （10^-6 cm^3.TP/g） are 12.18 and 3.5.98 for the Changzhougou and Dahongyu formations respectively. It was reported that the world＇s oldest micrometeorites had been found in the Meso-Proterozoic Satakunta Formation, Finland

关键词： Proterozoic cosmic spherule helium isotopes extraterrestrial material carbonaceous chondrite

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 New SHRIMP Age of the Xiamaling Formation in the North china Plate and Its geological Significance

引用

Acta Geologica Sinica(English Edition) 2007年第6期81卷 1103-1109页

作者： GAO Linzhi~(1,*)ZHANG Chuanheng~2 SHI Xiaoying~2 ZHOU Hongrui~2 WANG Ziqiang~2 SONG Biao~(1,3. 1 institute of Geology,chinese academy of {3. Sciences,beijing 100037,china 2 china University of Geosciences(beijing),beijing 100083.china 3.beijing SHRIMP Central,100037 beijing,china institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China

Setting up the hypostratotype of late Precambrian is the main aim of the research on the Meso-and Neoproterozoic in North *** chronostratigraphic position is the key in this study. However,many key horizons have not been calibrated with the high-quality isotopic *** the reported new U-Pb age with the Sensitive High-Resolution Ion Microprobe（SHRIMPⅡ）,a zircon U- Pb age was obtained of the ash bed in the Xiamaling Formation in North china Plate,yielding a weighted mean;Pb/;U age of 13.8±12 *** is the first SHRIMP U-Pb age from the Xiamaling Formation in the North china Plate,and represents the depositing time of the middle part of the Xiamaling *** zircon age plays an important role to understanding geological evolution of the North china Plate during Meso-and Neoproterozoic.

关键词： SHRIMP U-Pb Dating Mesoproterozoic Xiamaling Formation North china Plate

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

Identification of Potential Mineral Fields with Directional Wavelet Transform:Application to Mineral Exploration

引用

地学前缘 2009年第S1期16卷 171-172页

作者： Dianhua Cao,Anjian Wang institute of Mineral resources,chinese {3. of {4. Sciences,beijing 100037,china.

For the sustainable supply of mineral resources, blind deposits are becoming the emphasis of exploration after long-period exploitation of exposed *** collection and analysis of gravity or magnetic data represents one of the cheapest ways of large-scale geophysical *** the identification of potential mineral fields,we can get the map of worms or skeletonizations showing

关键词： potential field directional wavelet transform multidirectional and multiscale edges detection mineral exploration

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：