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Study on lithogeochemistry of Middle Jurassic basalts from southern china represented by the Fankeng basalts from Yongding of Fujian Province

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Science china earth sciences 2006年第10期49卷 1020-1031页

作者： ZHOU Jincheng1,2, JIANG Shaoyong1,2, WANG Xiaolei1,2, YANG Jinghong 1,2 & ZHANG Mengqun 3.1. State Key Laboratory of Mineral Deposit Research, nanjing university, nanjing 210093. china 2. Department of earth {3., nanjing university, nanjing 210093. china 3. Modern Analysis Center, nanjing university, nanjing 210093. china 1. State Key Laboratory of Mineral Deposit Research Nanjing University Nanjing 210093 China 2. Department of earth sciences Nanjing University Nanjing 210093 China 3. Modern Analysis Center Nanjing University Nanjing 210093 China

There exists an E-W trending Middle Jurassic volcanic zone in southern china. The Fankeng basalts in the Yongding basin of Fujian Province are considered to be a typical example. The Fankeng basalts have TiO2 contents in the range of 1.92%-3.21%. They are classified as high-Ti basalts. They also have higher total Fe (averaging FeO* = 11.09%). The Middle Jurassic Fankeng basalts from southwestern Fujian have obvious distinctive lithogeochemical features from early Cre- taceous basalts from southeastern coast of china. They have higher HFSE, such as Th, Nb, Ta, Zr and Ti. Their element ratios related with HFSE, such as Zr/Ba, La/Nb, La/Ta ,Zr/Y, Ti/Y, Ba/Nb, K/Ti and Rb/Zr are similar to those of OIB. The most samples have ε Nd(T) of-0.70-0.24, which are near chondrite. Some samples have higher ε Nd(T) of ***, these basaltic magmas might be derived from depleted asthenospheric mantle. The lithogeochemical characteristics of the Fankeng basalts may be caused by interaction between asthenosphere and lithosphere at the time. The (Early-) Middle Jurassic basalts and gabbros from southeastern Hunan, southern Jiangxi and northern Guangdong provinces show similar geochemical features to those of the Fankeng basalts from the Yongding of Fujian. Occurrence of these OIB-type basalts in the area may be regarded as the petrological mark of upwelling of asthenosphere at the time. Upwelling of asthenosphere has led to tectonic extension and the formation of rifted basin in the area.

关键词： interaction between asthenosphere and lithosphere, lithogeochemistry, basalts, Middle Jurassic, southern china.

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Depth zonation of Arenigian acritarchs in South china

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Chinese Science Bulletin 1997年第3期42卷 248-251页

作者： XU WanhongDepartment of earth sciences, nanjing university,{3. Department of earth sciences Nanjing University Nanjing China

STAPLIN revealed that palaeoenvironment changes seem to control acritarch distribution patterns. However, scientists have been puzzled by the fact that characteristic offshore acritarchs occur with nearshore ones. This note demonstrates depth zonation of Arenigian acritarchs in South china and reveals the variation of water depth in South china during the Arenig Age.

关键词： South china Arenigian acritarch depth zonation.

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EPR studies of Mn^(2+) in the Loess Plateau of central china: Implication for variation of the East Asia summer monsoon

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Chinese Science Bulletin 1998年第1期43卷 72-75页

作者： CHEN Jun\+1, JI Junfeng\+1, SU Yuanxia\+2 and LU Huayu\+3.. Department of earth sciences, nanjing university,{3. 2. Center of Material Analysis, nanjing university,{3. 3. Xi’an Laboratory of Loess and Qu Department of earth sciences Nanjing University Nanjing China Center of Material Analysis Nanjing University Nanjing China Xi’an Laboratory of Loess and Quaternary Geology Chinese Academy of Sciences Xi’an China

Mn 2+ EPR intensity recorded in the Chinese loess_paleosol sequence shows close correlation with magnetic susceptibility and Sr content as well as the oscillation of paleoclimate. Thus Mn 2+ EPR signal can serve as an... 详细信息

关键词： paleomonsoon loess paleosol EPR signal of Mn 2+

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Ultra-microbes are the minerogenetic constructors of oceanic polymetallic nodules

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Chinese Science Bulletin 1997年第8期42卷 617-624页

作者： CHEN Jianlin, ZHANG Fusheng and BIAN Lizeng1 Second Institute of Oceanography, State Oceanic Administration, Hangzhou 3.0012, china 2 Center for Materials Analysis, nanjing university, nanjing 210093. china 3. Department of {3. sciences, nanjing university, nanjing 210093. china Second Institute of Oceanography State Oceanic Administration Hangzhou China Centu for Materials Analysis Nanjing University Nanjing China Department of earth sciences Nanjing University Nanjing China

Polymetallic nodules (mangnese nodules) are a typical kind of manganese oncolites The distribution of smooth sur-face and knobbly manganese nodules is closely related to the geological background of the mine field. A systematic study on their inner laminae structure and features suggests that they are the products of millions of years reproduction and accumulation of the recently found Miniactinomyces chinensis and Spirisophaerospora pacijica .

关键词： oceanic manganese nodule stromatolite ultra-microbe biolite.

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Domain structures and copper vacancies in natural low-djurleite (Cu_(1.93.S)

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Chinese Science Bulletin 2001年第6期46卷 502-504页

作者： SUN Tao & XUE JiyueDepartment of earth sciences. nanjing university.{3. Department of earth sciences Nanjing University Nanjing China

Based on HRTEM studies, the domain structure and the copper vacancy model of Dongxiang low-djurleite are discussed. The HRTEM images show: ( i ) The domain structures are the intergrowth between djurleit (dj) and digenite (dg) on nm scale. Although there is a transition area which appears as hexagonal-chalcocite-like structure between them, they still follow orientation relationship of (100)dj//(111)dg. (ii) 1.56%-3.12% vacancies of Cu are present in low-djurleite. There are 1-2 Cu vacancies aver-agely in every b0/2 of the unit cell. This ratio is coincident to the composition of djurleite (Cu1.93.1.97S)

关键词： djurleite HRTEM images domain structure copper vacancies Dongxiang in Jiangxi Province.

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The role of aerial algae in the formation of the landscape of the Yunnan Stone Forest,Yunnan Province, china

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Science china earth sciences 2004年第9期47卷 846-864页

作者： TIAN Youping1,3. ZHANG Jie2, SONG Linhua1 & BAO Haosheng2 1. Institute of Geographic sciences and Natural Resources Research, Chinese Academy of sciences, Beijing 100101, china 2. Department of Geography,{3., nanjing 210093. china 3. School of earth sciences and Resources, china university of Geosciences, Beijing 100083. china Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Department of Geography Nanjing University Nanjing 210093 China School of earth sciences and Resources China University of Geosciences Beijing 100083 China

Aerial algae on the surface of carbonate rocks at the Stone Forest, Shilin County, Yunnan Province, china, and their bioerosion were investigated in the field and studied in the laboratory in detail. Through the observation, identification and statistics of more than one hun- dred algal samples and rock samples with the optical microscopes (stereomicroscope, biological microscope) and the scanning electronic microscope (SEM), the relationships between erosional forms on the surface of the Stone Forest and algae and/or algal communities and the genetic mechanism for the formation of erosional forms were analyzed. It is suggested that aerial algae play an active role in bioerosive processes that may affect the formation of karst erosional forms. These effects include both direct and indirect ones. The direct effect is the initiative control (algal shape-controlling role) of algae on the formation of karst forms of various scales, mostly mi- cro-scale (3.) and minor-scale (10-3.10-1m) erosional forms. The algal shape-controlling roles can be divided into the algal individual shape-controlling role and the algal community shape-controlling role. The former mostly controls the formation of micro-scale erosional forms, while the latter mostly controls the formation of micro-scale and smaller minor-scale erosional forms. The indirect effect refers to the promoting role of algae in the formation of karst forms, which may affect the formation of karst forms of all types and scales. The bioerosion of algae accelerates the weathering process of the whole Stone Forest karst landforms.

关键词： aerial algae, bioerosion, the Stone Forest, Yunnan Province, china.

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Sorption behavior of U(VI), ^(23.)U(VI) and ^(23.)U(VI) onto fracture-filling clays in Beishan granite, Gansu: Application to selecting the site of high-level radwaste repository in china

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Science china earth sciences 2005年第10期48卷 1649-1655页

作者： MIN Maozhong1,2, LUO Xingzhang3. WANG Ju4, JIN Yuanxin4 & WANG Rucheng1 1. Department of earth sciences, State Key Laboratory of Mineral Deposit Research, nanjing university,{3. 2. Center of Materials Analysis, nanjing university,{3. 3. Department of Environmental Science and Engineering, nanjing university,{3. 4. Beijing Geology Institute, Nuclear Industry, Beijing 100029, china Department of earth sciences State Key Laboratory of Mineral Deposit Research Nanjing University Nanjing China Center of Materials Analysis nanjing university nanjing china Department of Environmental Science and Engineering nanjing university nanjing china Beijing Geology Institute Nuclear Industry Beijing china

The first results of sorption experiments of U(VI), 23.U(VI) and 23.U(VI) onto original (unpurified) fracture-filling clays from No.1 monzonitic granite intrusion, Beishan area, Gansu Province, china are reported. The monzonitic granite intrusion is a potential location for a high-level radwaste (HLW) repository in china. The present experimental results show that the maximum U(VI) sorption reached 92% at near-neutral pH and the distribution coefficient (Kd) was 1226 mL/g. A high sorption capacity of the fracture-filling clays in host rock on radioactive ele-ments is necessary for HLW deep geological disposal repository. No preferential sorption of 23.U onto the clays was found. Finally, the sorption of U(VI) onto the clays was also modeled using a surface complexation model.

关键词： HLW geological disposal repository, granite, uranium, radionuclide, clay, sorption.

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Preparation and Characterization of Nanocomposite MgFe_2O_4/SiO_2

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Journal of Wuhan university of Technology(Materials Science) 2009年第3期24卷 354-358页

作者：徐莉 College of Science Nanjing Forestry University

Nanocomposites MgFe2O4/SiO2 were successfully synthesized by the sol-gel method in the presence of N, N-dimethylformamide （DMF）. The formation of pure MgFe2O4 was confirmed by powder X-ray diffraction （XRD） and electron diffraction. The structural evolution of MgFe2O4 nanocrystals was followed by powder X-ray diffraction and IR absorption spectroscopy. The formation of spinel structure of MgFe2O4 started at 800 ℃, and completed at 900 ℃, The transmission electron microscopy （TEM） measurements suggest that the particle sizes increase with the increasing annealing temperature, and the mean particle sizes of the spherical samples annealed at 800 ℃, 900 ℃ and 1 050 ℃ are ca. 3.nm, 8 nm and 11 nm, respectively. Magnetization measurements at room temperature and 78 K indicate supemaramagnetic nature of these MgFe2O4 nanocrvstals.

关键词： nanocomposite sol-gel magnesium ferrite magnetic property

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Origin of the Red earth sequence on the northeastern Tibetan Plateau and its implications for regional aridity since the middle Miocene

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Science china earth sciences 2006年第5期49卷 505-517页

作者： WANG Xianyan1,7, LU Huayu1,2, JI Junfeg3. WANG Xiaoyong1,7, ZHAO Jingbo4, HUANG Baochun5 & LI Zhen6 1. SKLLQG, Institute of earth Environment, Chinese Academy of sciences, Xi’an 710075, china 2. Department of Urban and Resources sciences, nanjing university, nanjing 210093. china 3. Department of earth sciences, nanjing university, nanjing 210093. china 4. Department of Geography, Shaanxi Normal university, Xi’an 710062, china 5. Institute of Geology and Geophysics, Chinese Academy of sciences, Beijing 100029, china 6 Department of Geography, Qinghai Normal university, Xining 810008, china 7. Graduate School of the Chinese Academy of sciences, Beijing 10003., china 1. SKLLQG Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 7. Graduate School of the Chinese Academy of sciences Beijing 100039 China 2. Department of Urban and Resources sciences Nanjing University Nanjing 210093 China 3. Department of earth sciences Nanjing University Nanjing 210093 China 4. Department of Geography Shaanxi Normal University Xi’an 710062 China 5. Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 6. Department of Geography Qinghai Normal University Xining 810008 China

The Red earth deposit around Xining, northeastern Tibetan Plateau, has beenstudied in terms of soil micro-structure, grain-size distribution, major- and trace-elementchemistry and magne-tostratigraphy. Field investigations indicate that the Red earth sequenceconsists of 25 visually definable yellow-brown and weakly-developed soils interbedded with reddishstrongly-developed soils, and has a similar structure to the aeolian Red Clay deposit on the ChineseLoess Plateau. Grain-size analysis shows that the Red earth deposit is very fine-grained with anegligible sand fraction ( > 63.μm). Thin-section observations under light microscopy show that thedeposit has a clayey texture and the coarse fraction ( > 10 μm) mainly consists of quartz,feldspar and micas. Pyroxene and hornblende were also observed. This mineralogical composition ofthe coarse fraction is similar to that of the Quaternary loess. In addition, all of the mineralgrains are semi angular semi-angular and are generally finer than 63.μm. There is a good agreementbetween the major and minor trace element chemistry of loess-soil units and the Red earth *** REE distributions of the loess-soil and the Red earth deposit are similar in shape, withenriched LREE and fairly flat HREE profiles and a clear negative Eu anomaly. The geochemicalcharacteristics of the Red earth deposit are also identical to those of upper continental crust,thus indicating a wind-blown origin. Magnetostratigraphic investigation shows that onset of the Redearth deposition predates 11.4 Ma BP (13.6 Ma at a nearby site). The distribution of the reportedMiocene aeolian loess at Qin''an of the Loess Plateau is still unknown. Our results indicate thatthis aeolian deposit had extended to the northeastern Tibetan Plateau by at least the middleMiocene. The similarity of the element geochemistry between the Red earth deposit and the overlyingloess shows that they may have similar sources and dynamic transport system, and may indicate thatthe

关键词： Red earth deposit, Northeastern Tibetan Plateau, aeolian deposit, aridity of Asia, the middle Miocene.

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Study on the thermal stability and electrical properties of the high-k dielectrics (ZrO_2) _x(SiO_2)_(1-x)

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Science china(Technological sciences) 2009年第8期52卷 2222-2226页

作者： Lü ShiCheng1,2, YIN Jiang1,2, XIA YiDong2,3. GAO LiGang2,3.& LIU ZhiGuo2,3.1 Department of Physics, nanjing university, nanjing 210093. china 2 National Laboratory of Solid Sate Microstructures, nanjing university, nanjing 210093. china 3.Department of Materials Science and Engineering, nanjing university, nanjing 210093. china 1. Department of Physics Nanjing University Nanjing 210093 China 2. National Laboratory of Solid Sate Microstructures Nanjing University Nanjing 210093 China 3. Department of Materials Science and Engineering Nanjing University Nanjing 210093 China

(ZrO2)x(SiO2)1-x (Zr-Si-O) films with different compositions were deposited on p-Si(100) substrates by using pulsed laser deposition technique. X-ray photoelectron spectra (XPS) showed that these films remained amorphous after annealing at 800℃ with RTA process in N2 for 60 s. The XPS spectra indi- cated that Zr-Si-O films with x=0.5 suffered no obvious phase separation after annealing at 800℃, and no interface layer was formed between Zr-Si-O film and Si substrate. While Zr-Si-O films with x >0.5 suffered phase separation to precipitate ZrO2 after annealing under the same condition, and SiO2 was formed at the interface. To get a good interface between Zr-Si-O films and Si substrate, Zr-Si-O films with bi-layer structure (ZrO2)0.7(SiO2)0.3.(ZrO2)0.5(SiO2)0.5/Si was deposited. The electrical properties showed that the bi-layer Zr-Si-O film is of the lowest equivalent oxide thickness and good interface with Si substrate.

关键词： high-k dielectric film pulsed laser deposition pseudo ternary alloy

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