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Science Bulletin 2001年第22期46卷 1912-1916页

作者： LIU Jingbo, YE Kai CONG Bolin, Maruyama Shegnori & FAN Hongruiinstitute of geology and geophysics, chinese academy of sciences, Beijing {4., china Department of Earth and Planetary sciences, Tokyo institute of Technology, 2-12-1 Ookayama, Meguro Tokyo, 152, Japan institute of geology and geophysics Chinese Academy of Sciences Beijing China Department of Earth and Planetary sciences Tokyo Institute of Technology Meguro Tokyo Japan

The mineral inclusions in zircon from gneisses in ultra-high pressure (UHP) zone of the Dabie Mountains were identified by using a laser Raman microspectrometer. Coesite occurs as inclusions in zircons from all types of gneiss. Other important minerals, such as jadeite, omphacite, aragonite, barite, and anhydrite were also found as inclusion minerals. These discoveries indicate that ( i) gneissic country rocks had metamorphosed at the same time as the enclosed eclogites; and (ii) SO4.2 -bearing fluids were presentin the UHP metamorphic process, which is manifested by occurrence of barite and anhydrite coexisting with coesite.

关键词： Coesite inclusions in zircon from gneisses identified by laser Raman microspectrometer in ultra-high pressure zone of Dabie Mountains,china high

Boron isotopic fractionation in laboratory inorganic carbonate precipitation:Evidence for the incorpora-tion of B(OH)_3 into carbonate

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Science china Earth sciences 2008年第12期51卷 1776-1785页

作者： XIAO YingKai1,2, LI HuaLing1,3, LIU WeiGuo4. WANG XiuFang1 & JIANG ShaoYong5 1 Qinghai institute of Salt Lakes, chinese academy of sciences, Xining 810008, china 2 State Key Laboratory of Environmental Geochemistry, institute of Geochemistry, chinese academy of sciences, Guiyang 550002, china 3 Nanjing institute of geology and Mineral Resources, Nanjing 210016, china 4.State Key Laboratory of Loess and Quaternary geology, institute of Earth Environment, chinese academy of sciences, Xi’an 710075, china 5 State Key Laboratory for Mineral Deposits Research, Department of Earth sciences, Nanjing University, Nanjing 210093, china 1. Qinghai institute of Salt Lakes Chinese Academy of Sciences Xining 810008 China 2. State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China 3. Nanjing institute of geology and Mineral Resources 210016 Nanjing China 4. State Key Laboratory of Loess and Quaternary geology Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 5. State Key Laboratory for Mineral Deposits Research Department of Earth Sciences Nanjing University Nanjing 210093 China

A laboratory inorganic carbonate precipitation experiment at high pH of 8.96 to 9.34.was conducted, and the boron isotopic fractionations of the precipitated carbonate were measured. The data show that boron isotopic fractionation factors (αcarb-3) between carbonate and B(OH)3 in seawater range 0.937 and 0.965, with an average value of 0.953. Our results together with those reported by Sanyal and collabo-rators show that the αcarb-3 values between carbonate and B(OH)3 in solution are not constant but are negatively correlated with the pH of seawater. The measured boron isotopic compositions of carbonate precipitation (δ11Bcarb) do not exactly lie on the best-fit theoretical δ 11B4.pH curves and neither do they exactly parallel any theoretical δ 11B4.pH curves. Therefore, it is reasonable to argue that a changeable proportion of B(OH)3 with pH of seawater should also be incorporated into carbonate except for the dominant incorporation of B(OH)4. in carbonate . Hence, in the reconstruction of the paleo-pH of sea-water from boron isotopes in marine biogenic carbonates, the use of theoretical boron isotopic frac-tionation factor (α4.3) between B(OH)4. and B(OH)3 is not suitable. Instead, an empirical equation should be established.

关键词： boron isotopic fractionation biogenic carbonate B(OH)3 incorporation

A REVISION ON SIGNIFICANCE AND USING RANGE OF THE LAW OF SUPERPOSITION

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Scientia Geologica Sinica 2001年第2期 129-132页

作者： Zhang Shouxin institute of geology and geophysics, chinese academy of sciences, Beijing,{4., china

The law of superposition is not universal. Its use in stratigraphy has met challenges and puzzles in the past several hundred years. It is a truth only suitable to any local single section of lithostratigraphy, but it is unsuitable for a large region. The author makes four revisions for its significance and use range. Finally, the principle of diachronism suitable to large regions is proposed.

关键词： A REVISION ON SIGNIFICANCE AND USING RANGE OF THE LAW OF SUPERPOSITION rock

The age of the plant fossil assemblage in the Liuqu Conglomerate of southern Tibet and its tectonic significance

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Progress in Natural Science:Materials International 2006年第1期16卷 55-64页

作者： FANG Aimin1, YAN Zhen1, LIU Xiaohan2, PAN Yusheng1, LI Jiliang1, YU Liangjun1, HUANG Feixing2 and TAO Junrong3 (1.Laboratory of Lithosphere Tectonic Evolution, institute of geology and geophysics, chinese academy of sciences, Beijing {4., china 2. institute of Tibet Plateau Research, chinese academy of sciences, Beijing 100085, china 3. institute of Botany, chinese A cademy of sciences, Beijing 100093, china) Laboratory of Lithosphere Tectonic Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China institute of Tibet Plateau Research Chinese Academy of Sciences Beijing 100085 China institute of Botany Chinese A-cademy of Sciences Beijing 100093 China

The Liuqu Conglomerate, situated to the south of Yarlung Tsangbo Suture Zone (YTSZ), is a suit of molasse formed in a foreland basin of the Himalayan orogenic belt after the collision between the two plates of the Indian and Eurasion, It is of great significance in constraining the younger limit time of the collision of the two plates and providing stratigraphic evidence to reveal the post-colli sional tectonic evolution and uplifting history of the Tibet plateau. However, the age of this molasse suit and its correlation to other synchronous strata distributed in southern Tibet have been in great disputes for a long time. Especially in recent years, argues on its ages are growing violently with the recognition of the great sedimentary tectonic significances of this molasse. During the field work carried out recently on this molasse suit, a lot of plant fossils were found preserved in fairly good conditions in the upper part of this strata, which is of great help in determining its age. By identification, the assemblage of the plant fossils belongs to a tropic to subtropic flora developed in the southern margin of the Northern Hemisphere supercontinent during the Middle to Later Eocene, which can provide good constraint on its formation age. This paper is to give a brief introduction of the plant assemblage and its age, and to discuss their tectonic significances.

关键词： Liuqu conglomerate plant fossils age Eocene Tectonic implications.

ADSORPTION OF CLINOPTILOLITE TO PHOSPHORIC IONS

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Scientia Geologica Sinica 2000年第2期 221-225页

作者： HAN Cheng (institute of geology and geophysics, chinese academy of sciences, Beijing {4., china)

When an exchange reaction takes place between clinoptilolite and solube phosphate solutions with cation exchange between the zeolite and solution, it occurres also for the zeolite to absorb phosphoric *** of the zeolites to Phosphoric ions may be related to a weak bonding action of Al in the zeolihc anionic framework with Phosphoric ions, besides that it is related to exchangeable Ca2+of the zeolites. Phosphoric ions absorbed by the zeolites can be eluted with some solutions. Adsorption and desorption of clinoptilolite to phosphoric ions have important values in agricultural production

关键词： NH ADSORPTION OF CLINOPTILOLITE TO PHOSPHORIC IONS SO

Sorption behavior of U(VI), ^(234.U(VI) and ^(238)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, Nanjing 210093, china 2. Center of Materials Analysis, Nanjing University, Nanjing 210093, china 3. Department of Environmental Science and Engineering, Nanjing University, Nanjing 210093, china 4. Beijing {4. 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), 234.(VI) and 238U(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 234. 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.

Cosmogenic ^(21)Ne concentrations and exposure ages of summit bedrocks in the Grove Mountains,Antarctica

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Science china Earth sciences 2010年第4期53卷 518-521页

作者： KONG Ping1,2,DING Lin2,LAI QingZhou2 & HUANG FeiXin3 1 Key Laboratory of the Earth’s Deep Interior,institute of geology and geophysics,chinese {4. of sciences,Beijing 100029,china 2 Key Laboratory of Continental Collision and Plateau Uplift,institute of Tibetan Plateau Research,chinese {4. of sciences,Beijing 100085,china 3 institute of Mineral Resources Research,china Metallurgical geology Bureau,Beijing 100025,china 1. Key Laboratory of the Earth’s Deep Interior Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China2. Key Laboratory of Continental Collision and Plateau Uplift Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China3. Institute of Mineral Resources Research China Metallurgical Geology Bureau Beijing 100025 China

Various sources of 21Ne and 22Ne exist in surface rocks:cosmogenic,in situ nucleogenic from internal U and Th,trapped crustal nucleogenic and trapped *** paper reports the first measurement,in china,of cosmogenic 21Ne and 22Ne in surface *** developed a unique sample pre-treatment procedure that effectively removed inclusions inside quartz grains,and thus maximally reduced nucleogenic contributions of 21Ne and ***-heating experiments show that concen-trations of cosmogenic 21Ne and 22Ne in summit bedrock samples R9202 and R9203 from Grove Mountains,Antarctica,are(3.83±0.87)×108 and(5.22±0.51)×108 atoms/g,*** corresponding minimum exposure ages are 2.2±0.5 and 3.0±0.3 *** indicates that the ice sheet in East Antarctica was uncovered the crest of Mount Harding,a typical nunatak in Grove Mountains,since at least mid-Pliocene.

关键词： 21Ne cosmogenic nuclide exposure age Antarctica Grove Mountains

Provincialism of the late Middle through middle Late Cambrian paraconodonts and protoconodonts

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chinese Science Bulletin 2001年第5期46卷 433-438页

作者： DONG XipingDepartment of geology, Peking University, Beijing 100871, china Laboratory of Paleobiology & Stratigraphy, Nanjing institute of geology and Palaeontology,{4., Nanjing 210008, china Department of geology Peking University Beijing China Laboratory of Paleobiology & Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China

Quantitative paleoprovincialism is studied, using a coefficient of similarity (CS) formula. The results indicate that the provincialism of the late Middle through middle Late Cambrian paraconodonts and protoconodonts did exist. The provincialism of Ordovician conodonts can be traced back to late Middle Cambrian. The North china Province and South china Province can be recognized in late Middle Cambrian, whereas the North china Province, South china Province and Balitca Province can be recognized respectively in early Late Cambrian and middle Late Cambrian. The possibility that the larger units of provincialism, i.e. Faunal Regions existed in the areas mentioned above is discussed. It is inferred that the Midcontinent Faunal Region and the Atlantic Faunal Region had existed in early Late Cambrian and middle Late Cambrian. The North china Province was the secondary unit of provincialism in the Midcontinent Faunal Region, while the Baltica Province was that in the Atlantic Faunal Region. The South china

关键词： paraconodonts and protoconodonts provincialism late Middle Cambrian through middle Late Cambrian.

Genesis of excess argon in phengite and significance of ^(4.)Ar-^(39)Ar age spectra for omphacite:A case study on UHP eclogite of South Dabie Terrain,china

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chinese Science Bulletin 2000年第15期45卷 1345-1351页

作者： WANG Songshan, GE Ningjie, SANG Haiqing & QIU Ji1. institute of geology and geophysics, chinese academy of sciences, Beijing {4., china 2. Department of Earth and Space Science, University of Science and Technology of china, Hefei 230026, china Correspondence should be addressed to Wang Songshan institute of geology and geophysics Chinese Academy of Sciences Beijing China Department of Earth and Space Science University of Science and Technology of China Hefei China

The Ar-Ar dating of phengite and omphacite in ultrahigh-pressure (UHP) eclogite of Bixiling and Hengchong in the South Dabie Terrain shows that the content range of excess argon is as high as (0.4.1.3)×10 8 mol· g 1. The genesis of the excess argon is discussed. The Ar-Ar age spectra of omphacite could not support the opinion that the UHP metamorphism occurred in Caledon epoch and pre-Caledon epoch.

关键词： South Dabie Terrain ultrahigh-pressure metamorphics phengite omphacite excess argon.

Hydrogen isotopic characteristics and their genetic relationships for individual n-alkanes in plants and sediments from Zoigê marsh sedimentary environment

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Science china Earth sciences 2010年第9期53卷 1329-1334页

作者： DUAN Yi1, ZHENG ChaoYang2 & WU BaoXiang1 1 Key Laboratory of Petroleum Resources Research, institute of geology and geophysics, chinese academy of sciences, Lanzhou 730000,{4. 2 Department of geology, Northwest University, Xi’an 710069,{4. 1. Key Laboratory of Petroleum Resources Research Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou 730000 China2. Department of Geology Northwest University Xi’an 710069 China

To understand internal relations of their hydrogen isotopic compositions in typical marsh environment, we, using GC-IRMS analytical technique, measured the hydrogen isotopes of individual n-alkanes in the herbaceous plant, woody plant leaf, and sediments from Zoigê marsh in china. The results show significant differences in the hydrogen isotopic compositions of n-alkanes among the different kinds of plants and the different species in the same kind. δD values of n-alkanes in the herbaceous plants (from -254. to -184.) are lighter than those in woody plant leaf ( from -195‰ to -14.‰ ), and the hydrogen isotopic compositions of n-alkanes in K. tibetica P. are lighter than P. pratensis L. The mean δD values of n-alkanes in the sediments from Zoigê marsh reflect that they were derived from herbaceous plants, which is consistent with the peat samples being composed mainly of herbaceous plant remnants. The significant differences in hydrogen isotopic compositions of n-alkanes among the sedimentary samples are caused possibly by environment factors and the difference in input quantity of different herbaceous plants. A certain negative correlation exists between the δ13C and δD values of n-alkanes in the samples, and plant types can be distinguished using the cross plot of δD vs. δ13C values of n-alkanes in the plants. These data and recognitions provide scientific basis for hydrogen isotopic applied research of individual n-alkanes.

关键词： marsh environment plants sediments individual lipids hydrogen isotopes genetic relationship