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Ore-forming fluid and mineralization of Caijiaying and Dajing polymetallic ore deposits

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Science china Earth sciences 2004年第2期47卷 97-107页

作者： WANG Lijuan,WANG Jingbin, WANG Yuwang & ZHU Heping1. Key Laboratory of Mineral Resources, institute of geology and {2., {3. Academy of sciences, beijing 10002., china 2. beijing institute of geology for Mineral Resources, beijing 100012. china Correspondence should be addressed to Wang Lijuan (email: wlj@***) Key Laboratory of Mineral Resources Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China beijing institute of {2. for Mineral Resources Beijing China

Fluid inclusions from the Dajing and Caijiaying deposits have nearly the same homogenization temperature. Correlation between temperature and salinity shows that both Sn- and Cu-bearing fluids Sn and Cu were present in the Dajing deposit but only one kind of fluids continuously evolved in the Caijiaying deposit. Study on rare earth elements (REE) in ancient fluid from the inclusions indicates that the fluid of Sn mineralizing stage in Dajing was derived from remelting magma of the continental crust, and the fluid of Cu-Pb-Zn mineralizing stage in the Dajing deposit and the fluid of Cu-Pb-Zn mineralization in the Caijiaying deposit were derived from the mantle. It is concluded that the Cu-Pb-Zn mineralizations in the Dajing and Caijiaying deposits resulted from the identical tectono-thermal event of magma-fluids induced by Mesozoic tectonic transition and extension in the eastern part of North china Craton.

关键词： Caijiaying, Dajing, Mesozoic tectonic transition, ore-forming fluid, REE.

Typical basin-fill sequences and basin migration in Yanshan, North china ——Response to Mesozoic tectonic transition

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Science china Earth sciences 2004年第2期47卷 181-192页

作者： LI Zhong, LIU Shaofeng, ZHANG Jinfang & WANG Qingchen1. institute of geology and {2., {3. Academy of sciences, beijing 10002., china 2. china University of Geosciences, beijing 100083. chinaCorrespondence should be addressed to Li Zhong (email: lizhongd@***) institute of geology and {2. Chinese Academy of Sciences Beijing China china University of Geosciences Beijing China

Basin-fill sequences of Mesozoic typical basins in the Yanshan area, North china may be divided into four phases, reflecting lithosphere tectonic evolution from flexure (T3., flexure with weak rifting (J1+2., tectonic transition (J3., and rifting (K). Except the first phase, the other three phases all start with lava and volcaniclastic rocks, and end with thick coarse clastic rocks and/or conglomerates, showing cyclic basin development rather than simple cyclic rift mechanism and disciplinary basin-stress change from extension to compression in each phase. Prototype basin analysis, based on basin-fill sequences, paleocurrent distribution and depositional systems, shows that single basin-strike and structural-line direction controlling basin development had evidently changed from east-west to northeast in Late Jurassic in the Yanshan area, although basin group still occurred in east-west zonal distribution. Till Early Cretaceous, main structural-line strike controlling basins just turned to northeast by north in the studied area.

关键词： Yanshan, Mesozoic, basin-fill, paleocurrent, tectonic transition.

Control of atmospheric CO_2.concentrations by 2.50: A calculation on the emission rights of different countries

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Science china Earth sciences 2009年第10期52卷 1447-1469页

作者： DING ZhongLi1, DUAN XiaoNan2. GE QuanSheng3.& ZHANG ZhiQiang4 1 institute of {2. and geophysics, {3. Academy of sciences, beijing 10002., china 2.The General Office of {3. Academy of sciences, beijing 100864, china 3.institute of Geographic sciences and Natural Resources Research, {3. Academy of sciences, beijing 100101, china 4 The Lanzhou Branch of the National Science Library, the Scientific Information Center for Resources and Environment, Lanzhou 73.000, china institute of geology and {2. Chinese Academy of Sciences Beijing China The General Office of chinese Academy of sciences Beijing China institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing China The Lanzhou Branch of the National Science Library the Scientific Information Center for Resources and Environment Lanzhou China

This paper is to provide quantitative data on some critical issues in anticipation of the forthcoming international negotiations in Denmark on the control of atmospheric CO2.concentrations. Instead of letting only a small number of countries dominate a few controversial dialogues about emissions reductions, a comprehensive global system must be established based on emissions allowances for different countries, to realize the long-term goal of controlling global atmospheric CO2.concentrations. That a system rooted in "cumulative emissions per capita," the best conception of the "common but differentiated responsibilities" principle affirmed by the Kyoto Protocol according to fundamental standards of fairness and justice, was demonstrated. Based on calculations of various countries' cumulative emissions per capita, estimates of their cumulative emissions from 1900 to 2.05, and their annual emissions allowances into the future (2.06―2.50), a 470 ppmv atmospheric CO2.concentration target was set. According to the following four objective indicators―total emissions allowance from 1900 to 2.50, actual emissions from 1900 to 2.05, emissions levels in 2.05, and the average growth rate of emissions from 1996 to 2.05―all countries and regions whose population was more than 3.0000 in 2.05 were divided into four main groups: countries with emissions deficits, countries and regions needing to reduce their gross emissions, countries and regions needing to reduce their emissions growth rates, and countries that can maintain the current emissions growth rates. Based on this proposal, most G8 countries by 2.05 had already expended their 2.50 emissions allowances. The accu-mulated financial value based on emissions has reached more than 5.5 trillion US dollars (2. dollars per ton of CO2.. Even if these countries could achieve their ambitious emissions reduction targets in the future, their per capita emissions from 2.06 to 2.50 would still be much higher than those of developing coun

关键词： international negotiations on climate change cumulative emissions per capita emission allowance

Sea level variations in the South china Sea inferred from satellite gravity,altimetry,and oceanographic data

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Science china Earth sciences 2012年第10期55卷 1696-1701页

作者： FENG Wei 1,2.ZHONG Min 1,3.& XU HouZe 1,3.1 State Key Laboratory of Geodesy and Earth’s Dynamics,{2. of Geodesy and geophysics,chinese Academy of {3.,Wuhan 43.077,china 2.Graduate University of chinese Academy of {3.,beijing 100049,china 3.{2. of geophysics,Huazhong University of Science and Technology,Wuhan 43.074,china State Key Laboratory of Geodesy and Earth’s Dynamics Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan China Graduate University of chinese Academy of sciences Beijing China institute of geophysics Huazhong University of Science and Technology Wuhan China

Sea level variations(SLVs) can be divided into two major components:the steric SLV and the mass-induced *** two components of SLV in the South china Sea(SCS) are studied by using satellite altimetry,GRACE(Gravity Recovery and Climate Experiment) satellite gravity,and oceanographic data on annual and inter-annual *** the annual timescale,the geographic distribution of mass-induced SLV's amplitude jointly estimated from altimetry and the ECCO(Estimation of the Circulation and Climate of the Ocean) model agrees very well with that from *** observes obvious seasonal mass-induced SLV in the SCS with annual amplitude of 2.7±0.4 cm,which is consistent with the annual amplitude of 2.7±0.3.cm estimated from the steric-corrected *** the inter-annual timescales,the mean SLV in the SCS shows a large oscillation,which is mainly caused by the steric *** trend of mean SLV inferred from altimetry in the SCS is 5.5±0.7 mm/yr for the period of 1993.2.09,which is significantly higher than the global sea level rise rate of 3.3.0.4 mm/yr in the same *** is no obvious trend signal in the mass-induced SLV detected from GRACE that indicates the water exchange between the SCS and its adjacent seas and land is in balance within the study period.

关键词： altimetry GRACE ECCO the South china Sea sea level variation

Cosmogenic ^(2.)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 {2. and geophysics,{3. Academy of sciences,beijing 10002.,china 2.Key Laboratory of Continental Collision and Plateau Uplift,institute of Tibetan Plateau Research,{3. Academy of sciences,beijing 100085,china 3.institute of Mineral Resources Research,china Metallurgical {2. Bureau,beijing 10002.,china Key Laboratory of the Earth’s Deep Interior Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Key Laboratory of Continental Collision and Plateau Uplift Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China institute of Mineral Resources Research China Metallurgical Geology Bureau Beijing China

Various sources of 2.Ne and 2.Ne 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 2.Ne and 2.Ne in surface *** developed a unique sample pre-treatment procedure that effectively removed inclusions inside quartz grains,and thus maximally reduced nucleogenic contributions of 2.Ne and ***-heating experiments show that concen-trations of cosmogenic 2.Ne and 2.Ne in summit bedrock samples R92.2.and R92.3.from Grove Mountains,Antarctica,are(3.83.0.87)×108 and(5.2.±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： 2.Ne cosmogenic nuclide exposure age Antarctica Grove Mountains

A formal model of fair exchange protocols

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Science in china(Series F) 2005年第4期48卷 499-512页

作者： QING Sihan1,2.3.& LI Gaicheng1,2.3.1. Engineering Research Center for Information Security Technology, {2. of Software, chinese Aca- demy of sciences, {3. 100080, china 2. {3. Zhongke Ansheng Corporation of Information Technology, {3. 100080, china 3. Graduate School of the chinese Academy of sciences, {3. 10003., china Engineering Research Center for Information Security Technology Institute of Software Chinese Academy of Sciences Beijing China beijing Zhongke Ansheng Corporation of Information Technology Beijing China Graduate School of the chinese Academy of sciences Beijing China

Based on the study of existing fair exchange protocols, this paper sets up an accurate formal model by stepwise refinement. In the process of refinement an unreliable channel is employed to simulate an attack behavior. The model provides a novel formal definition of exchanged items, and presents the formal goals for fairness, accountability, etc., reflecting the inherent requirements for fair exchange protocols across-the-board. In order to check, prove, and design fair exchange protocols effectively and efficiently, the model puts forward a novel property of abuse-freeness which applies to all fair exchange protocols, gives a formal definition for trust strand of the third party, and presents general criteria of designing a secure and effective fair exchange protocol. Taking a typical fair exchange protocol as an example, this paper presents the analysis steps of fair exchange protocols appealing to our model. An unknown attack is uncovered. The analysis reveals the process of a complete attack, discovering deeper reasons for causing an attack. Finally, we modify the flawed protocol and the revised protocol ensures the desirable properties.

关键词： events local causal relation local temporal relation global relation exchanged item security goals.

Representation of microscale ocean wavenumber spectrum correct to the second order

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Science china Earth sciences 2005年第4期48卷 549-554页

作者： YUAN Yeli2.& HUA Feng1,2.3.1. institute of Oceanology, {2. Academy of sciences, Qingdao 2.6071,{3. 2. Key Laboratory of Marine Science and Numerical Modeling, State Oceanic Administration, Qingdao 2.6061,{3. 3. Graduate School of the {2. Academy of sciences, beijing 10003.,{3. Key Laboratory of Marine Science and Numerical Modeling State Oceanic Administration Qingdao China institute of Oceanology Chinese Academy of Sciences Qingdao China Graduate School of the chinese Academy of sciences Beijing China

In this paper, the analytical representations of four wave source functions in high-frequency spectrum range are given on the basis of ocean wave theory and dimensional analysis, and the perturbation method is used to solve the governing equations of ocean wave high-frequency spectrum on the basis of the temporally stationary and locally homogeneous scale relations of microscale wave. The microscale ocean wavenumber spectrum correct to the second order has an explicit structure, its first order part represents the equilibrium between dif- ferent source functions, and its second order part represents the contribution of microscale wave propagation.

关键词： temporally stationary and locally homogeneous, source function in high-frequency spectrum range, microscale ocean wavenumber spectrum.

High-temperature phases of pyrophyllite and their evolutionary characteristics

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chinese Science Bulletin 1997年第2期42卷 140-144页

作者： WANG Ling and ZHANG Zhenyu1. Changsha institute of Geotectonics, chinese Academy of {2., Changsha 410013.{3. 2. institute of geology, chinese Academy of {2., beijing 10002.,{3. Changsha institute of Ceotectonics Chinese Academy of Sciences Changsha China institute of geology Chinese Academy of Sciences Beijing China

WITH the increase of heating temperature, phase of pyrophyllite will undergo a series of transformations. Former scholars have done some work in this respect; the temperature spans,however, were normally not more than 1150℃ and no relatively comprehensive results have been reported. Thus, the features of the phases from indoor temperature to melting point (1710℃±) for pyrophyllite and the entire evolutionary process of the phases are uncertain.

关键词： pyrophyllite high-temperature phase phase tranformation pyrophyllite anhydrite mullite cristobalite.

Distribution characteristics of magnetic susceptibility of the surface sediments in the southern Yellow Sea

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chinese Science Bulletin 2003年第B6期48卷 37-41页

作者： GE Shulan~(1,2.3., SHI Xuefa~1 & HAN Yibing~1 1. Key Laboratory of Marine Sedimentology and Environmental geology, First {2. of Oceanography, State Oceanic Administration. Qingdao 2.6061. china 2. {2. of geology and geophysics, chinese Academy of sciences, beijing 10002.. china 3. Graduate School. chinese Academy of sciences, beijing 10003.. china Key Laboratory of Marine Sedimentology and Environmental geology First Institute of Oceanography State Oceanic Administration Qingdao China institute of geology and {2. Chinese Academy of Sciences Beijing China Graduate School Chinese Academy of Sciences Beijing China

The characteristic distributions of magnetic susceptibility (MS) are analyzed on the basis of susceptibility of 172.surface sediment samples in the southern Yellow Sea (SYS). The preliminary results are as follows: first, the distributions clearly correspond to different modern sediment assemblages in the continental sea, which indicates different sediment origins. With the 3. μCGS isoline being taken as demarcation line, the study area can then be divided into section H (high MS value area) and section L (low MS value area). Section H is mainly adjacent to land with two main sources of the Changjiang River and the Huanghe *** L is mainly an eddy sediment area, where Yellow Sea Cold Water is entrenched all the year round. The distribution pattern of MS could tell apart strong or weak hydrodynamic conditions and has a close relation to the circulation system in this area. At the areas of the SYS Circumfluent and northern East china Sea (NECS) Circumfluent (weak hydrodynamic), the MS has low values, while in the areas of Coastal Current (strong hydrodynamic), the values are *** the same time, the oxidizing areas tend to take on higher MS, while the reducing areas have lower one. It seems safe to say that the MS in the continental sea reflects more of the sediment origin and sedimentary environment, which is different from that of loess, lake and surface soil as a climate proxy.

关键词：中国黄海表面沉积物磁化率等值线长江黄河旋涡沉积区循环系统