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Experimental study of ore gabbro liquid immiscibility

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Science china Earth Sciences 2005年第4期48卷 496-505页

作者： SANG Zunan1,2. XIA Bin1, ZHOU Yongsheng3.& JIN Zhenmin4 1. Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, china 2. Wuhan {2., Wuhan 43.072. china 3. Institute of Geology, china Seismological Bureau, Beijing 10002., china 4. Faculty of Earth Sciences, china {2. of geosciences, Wuhan 43.074, china 1. Guangzhou Institute of Geochemistry Chinese Academy of Sciences 510640 Guangzhou China 2. Wuhan university 430072 Wuhan China 3. Institute of Geology China Seismological Bureau 100029 Beijing China 4. Faculty of Earth Sciences China University of Geosciences 430074 Wuhan China

In this paper, the authors present the results of a preliminary experimental study on partial melting of fine-grained gabbro, Panzhihua, Sichuan Province, china. Experiments were conducted under (confining) pressure ranging from 450 to 500 MPa and temperature of 900— 12.0℃. The results show that the initial melt is distributed along grain boundaries and triple junctions. Liquid immiscibility phenomena are noted in the melt with two compositional different melt phases, i.e. matrix and sphere phases. The matrix phase is relatively rich in Si, Al and K, and is depleted in Mg, Fe, Ca, Na and Ti, whereas the sphere phase shows opposite trends. The calculation of the melt free energy indicates that the liquid immiscibility is governed by the rule of thermodynamics, as the liquid immiscibility would result in the decrease in free energy of the melt system. The field relationships suggest that the liquid immiscibility may have played an important role in the generation of ore magma of Panzhihua V-Ti magnetite ore deposit. This study thus provides experimental constraints on the mechanism of the formation of V-Ti magnetite deposite.

关键词： partial melting, experimental study, gabbro, liquid immiscibility, ore formation mechanism.

Discovery of Paleogene marine stratum along the southern side of Yarlung-Zangbo suture zone and its implications in tectonics

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Science china Earth Sciences 2005年第5期48卷 647-661页

作者： LI Guobiao 1 , WAN Xiaoqiao 1 , LIU Wencan 1 , LIANG Dingyi 1 & Hyesu Yun 2.1. china university of {2., Beijing {3., china 2. Chungnam National university, Daejon, 3.5-3.0, Korea 1. china university of {2. 100083 Beijing China 2. Chungnam National university 305-350 Daejon Korea

The Jiachala Formatiom is a new lithostratigraphic unit set up in this paper. This is the first report on the Paleogene marine sequences and microfaunas in Gyangze to the southern side of the Yarlung-Zangbo suture zone. On the basis of fossil abundance, species diversity, dominant species and first and last occurrences of key species, three dinoflagellate assemblages and three polynological assemblages were recognized in the Jiachala Formatiom. They are in ascending order as follows: Apectodinium quinquelatum-Apectodinium hyperacanthum, Cannin- gia chinensis-Palaeoperidinium pyrophorum and Cymatiosphaera reticulosa-Samlandia chla- mydophora dinoflagellate assemblages, and Arliaceoipollenites baculatus-Anacolosidites sub- trudens, Aglaoreidia cyclops-Pinuspollenites microinsigis, and Elaeangnacites asper-Ilexpol- lenites iliacus polynological Assemblages. According to the assemblages, the age of the Jiachala Formation is referred to Paleocene-early Eocene. The preliminary study on the Jiachala Forma- tion shows that this group of Paleogene deposits accumulated in an underfilled peripheral fore- land basin which was in response to the load of the crust thickening resulted from the Asia-India collision. The stratigraphic evidences provided by the evolution of foreland basin indicate that the India-Asia initional collision should occure near the Cretaceous/Paleogene boundary. The de- velopment and evolution of the southern Tibet foreland basin was under the control of the stress field from the subduct-collision between India and Asia and the structure pattern of the basement. The withering of Tethys Sea might occur after early Eocene in the Gyangze basin and should be after Priabonian of late Eocene in southern Tibet.

关键词： Paleogene marine strata, Jiachala Formation, microfossils, underfilled peripheral foreland basin, initional collision, Gyangze.

Online uniform machine covering with the known largest size

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Progress in Natural Science:Materials International 2007年第11期17卷 1271-1278页

作者： Cao Shunjuan1,2.and Tan Zhiyi1,3.1. Department of Mathematics, Zhejiang university, Hangzhou 3.002., china 2. Department of Mathematics, Zhejiang Forestry university, Hangzhou 3.13.0, china 3. State Key Laboratory of CAD & CG, Zhejiang university, Hangzhou 3.002., china) Department of Mathematics Zhejiang University Hangzhou 310027 China Department of Mathematics Zhejiang Forestry University Hangzhou 311300 China State Key Laboratory of CAD & CG Zhejiang University Hangzhou 310027 China

This paper investigates the semi-online scheduling problem with the known largest size on two uniform machines. The objective is to maximize the minimum machine completion time. Both lower bounds and algorithms are given. Algorithms are optimal for the majority values of s≥1, where s is the speed ratio of the two machines. The largest gap between the competitive ratio and the lower bound is about 0.064. Moreover, the overall competitive ratio 2.matches the overall lower bound.

关键词： scheduling and covering uniform machine design and analysis of algorithm online competitive ratio

Paleomagnetic dating of the Cenjiawan Paleolithic site in the Nihewan Basin, northern china

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Science china Earth Sciences 2006年第3期49卷 295-303页

作者： WANG Hongqiang1,2. DENG Chenglong1, ZHU Rixiang1 & XIE Fei3.1. Paleomagnetism and Geochronology Laboratory (SKL-LE), Institute of Geology and Geophysics, Chinese Academy of Sci- ences, Beijing 10002., china 2. School of the Earth Sciences and Resources, china university of {3., Beijing 100083, china 3. Hebei Province Institute of Cultural Relics, Shijiazhuang 050000, china 1. Paleomagnetism and Geochronology Laboratory (SKL-LE) Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 2. School of the Earth Sciences and Resources China University of Geosciences Beijing 100083 China 3. Hebei Province Institute of Cultural Relics Shijiazhuang 050000 China

Rock magnetic and magnetostratigraphic investigations on a lacustrine sequence in the Nihewan Basin, northern china, which bears the Cenjiawan Paleolithic site, indicate that the dominant magnetic mineral and remanence carrier contained in the sediments is magnetite. While hematite co-exists with magnetite in some portions of the Cenjiawan sequence, where characteristic remanent magnetizations are carried by both magnetite and hematite. Measurements of anisotropy of magnetic susceptibility confirm that the Cenjiawan sequence has preserved the original sedimentary features and is suitable for magnetostratigraphic study. Paleomagnetic results indicate that the Cenjiawan Paleolithic site is formed just posterior to the Punaruu normal event, which is dated at about 1.1 Ma. Combined with the paleomagnetic results of the Donggutuo, Xiaochangliang and Majuangou sections, it is concluded that early humans were occupying the Nihewan Basin around 1.6, 1.3.and 1.1 Ma. This integrated result is significant to understanding the ability of migration and adaptation to the envi- ronment of early humans.

关键词： Nihewan Basin, Early Pleistocene, Cenjiawan, Paleolithic site, paleomagnetism.

Ev Surge Illuminates Pathto Sustainable Mobility

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中印对话（英文版） 2024年第1期38卷 56-58页

作者： china-lndia Dialogue 不详

china's Booming NEVs zhang Yifan occupation:PhD student at the school of Philosophy,Renmin university of{2. Birth Place:Panzhihua,Sichuan Current Residence:Lijiang,Yunnan Rapid advancements in technological innovation and energy transformation within the automotive industry in recent years have far exceeded *** market share of new energy vehicles(NEVs)in the automotive sector continues to grow,with globally recognized brands like Tesla and domestically acclaimed brands such as Xiaomi frequently capturing the public's attention.

关键词： Sustainable occupation globally

Conceptual design,data model and key techniques of“3. Assistant”

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中国有色金属学会会刊：英文版 2011年第S3期21卷 692-698页

作者： LI Qing-yuan1, ZHANG Xuan2. JIN Yang2. ZHOU Hui3. WANG Qian-jin3.WEI Zhan-yin1 1. Key Laboratory of Geo-Informatics, Chinese Academy of Surveying and Mapping, Beijing 10083., china 2. School of Geo-Science and Surveying Engineering, china university of Mining and Technology, Beijing {3., china 3. School of Geomatics, Liaoning Technical university, Fuxin 12.0}00, china [a] Key Laboratory of Geo-Informatics Chinese Academy of Surveying and Mapping Beijing 100830 China [b] School of Geo-Science and Surveying Engineering China University of Mining and Technology Beijing 100083 China [c] School of Geomatics Liaoning Technical University Fuxin 123000 China

Conceptual design, data model and key techniques of "Geo-engineer 3. assistant", an underground 3. GIS oriented to geology and mine application, were discussed. In particular, the importance of high-order smoothing triangular pieces to surface's fine expression in geological modeling was emphasized. The contour mode is the most favorite mode of the three modes about surface expression: DEM, TIN and contour. Topology in underground 3. modeling with CAGD was compared. From the view of boundary and coboundary, which is soul of IS 19107 (Geographic information spatial schema), 3. underground topology was re-examined.

关键词： 3. assistant true 3. GIS fine expression of surface contour mode 3. topology

South china's Gondwana connection in the Paleozoic:Paleomagnetic evidence

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Progress in Natural Science:Materials International 2004年第1期14卷 86-91页

作者： ZHANG Shihong*(School of Earth Sciences and Resources, china university of {2., Beijing {3., china) china Univ Geosci Sch Earth Sci & Resources Beijing 100083 Peoples R China

The reconstruction in which the South china Block (SCB) lies along the Great India Australia region of Gondwana margin is tested by using existing Paleozoic paleomagnetic data. Under the proposed reconstruction, all six high quality paleopoles from the SCB between the Early Cambrian and late Early Devonian (～400 Ma) are in good agreement with coeval paleopoles from Gondwana. Thereafter, the apparent polar wander paths for the SCB and Gondwana diverge markedly. This indicates that the SCB had been part of Gondwana and the connection was intact from at least Early Cambrian until late Early Devonian, but they began to separate by late Middle Devonian (～3.5 Ma).

关键词： South china block Gondwana paleomagnetism reconstruction

Restoration of eroded stratal thickness in key periods of tectonic change in a multi-stage superimposed Tarim Basin in china

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Journal of Palaeogeography 2012年第2期1卷 149-171页

作者： Liu Hao1, Wang Yingmin2.1. School of Marine Sciences, china university of {2. (Beijing), Beijing {3., china 2. School of {2., china university of Petroleum (Beijing), Beijing 102.49, china School of Marine Sciences China University of Geosciences (Beijing) Beijing 100083 China School of geosciences China University of Petroleum (Beijing) Beijing 102249 China

With an area of 56×104km2. the Tarim Basin is the largest inland basin in china and is also generally acknowledged as one of the most important areas for potential oil and gas exploration. On the basis of data from 2. regional seismic profiles and 40 drilling wells, 15 important first-order and second-order regional unconformities were *** all the main unconformities are superimposed unconfomities. Since the Cambrian, 5 key periods of tectonic change have occurred during the evolution of the Tarim Basin. The total eroded stratal thickness of the above-mentioned unconformities was calculated by using the method of virtual extrapolation of seismic reflection. The results indicate that the total eroded stratal thickness of different periods is quite different in different locations of the basin. Taking the Upper-Middle Ordovician as an example, its thickness restoration of eroded strata was calculated into individual stages i.e. its thickness restoration of eroded strata was calculated to different tectonic periods. Otherwise, as for the specific period of tectonic change, the underlying strata were, respectively eroded and thus the thickness restoration of eroded strata was calculated into individual intervals. Taking the Early Hercynian period as an example, the eroded stratal thickness was calculated into individual intervals to calculate the ratio of intervals of various ages occupying the total eroded thickness. The results show that for the same stratum, its degree of erosion is quite different in different periods and at different locations, due to the varying influence of tectonic movement. The unconformities of some key periods of tectonic change have different controls on the degree of erosion and the eroded range of the individual period of the underlying strata which are the typical characteristics of multi-stage superimposition of unconformities in the Tarim Basin.

关键词： Tarim Basin extrapolation of virtual surface key period of tectonic change superimposed unconformity restoration of eroded stratal thickness

Sm-Nd and zircon SHRIMP U-Pb dating of Huilanshan mafic granulite in the Dabie Mountains and its zircon trace element geochemistry

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Science china Earth Sciences 2005年第12期48卷 2081-2091页

作者： HOU Zhenhui1, LI Shuguang1, CHEN Nengsong2. LI Qiuli1 & LIU Xiaoming3.1. School of Earth and Space Sciences, university of Science and Technology of{2., Hefei 2.0}02.,{2. 2. The Key Laboratory of Continental Dynamics of the Ministry of Education, Northwest university, Xi’an 710069,{2. 3. Faculty of Earth Sciences,{2. university of geosciences, Wuhan 43.074,{2. 1. School of Earth and Space Sciences University of Science and Technology of China 230026 Hefei China 2. The Key Laboratory of Continental Dynamics of the Ministry of Education Northwest University 710069 Xi’an China 3. Faculty of Earth Sciences China University of Geosciences 430074 Wuhan China

The mafic granulites from Huilanshan are outcropped on the center of the Luotian dome in the northern Dabie Mountains. The Sm-Nd isochron defined by granulite-facies meta-morphic minerals (garnet + clinopyroxene + hypersthene) yields an age of 13. ± 18 Ma indicating the early Cretaceous granulite-facies metamorphism. The cathodoluminescence (CL) images of zircons from the granulite show clearly core-mantle-rim structures. The zircon cores are charac-terized by typical oscillatory zoning and highly HREE enriched patterns, which suggests their magma origin. Some zircon cores among them with little Pb loss give SHRIMP U-Pb ages rang-ing from 753.to 780 Ma, which suggests that the protolith of Huilanshan granulite is Neopro-terozoic mafic rocks. The zircon mantles usually cut across the oscillatory zone of the zircon cores have 3.10 times lower REE, Th, U, Y, Nb and Ta contents than the igneous zircon cores but have high common Pb contents. These characteristics suggest that they were formed by hydrothermal alteration of the igneous zircons. The part of zircon mantles with little Pb loss give a similar SHRIMP U-Pb age (716―780 Ma) to the igneous zircon cores, which implies that the hydrothermal events occurred closely to the magmatic emplacement. In view of the strong early Cretaceous magmatism in the Luotian dome, consequently, the Huilanshan mafic granulite was formed by heating of the Neoproterozoic mafic rocks in mid-low crust, which caused the granu-lite-facies metamorphism underneath the Dabie Mountains. The similarity between the granulite metamorphic age (13. ± 18 Ma) defined by Sm-Nd isochron and K-Ar age of 12.0}12. Ma given by amphible from the gneiss in Luotian dome suggests a rapid uplifting of the Luotian dome, which may result in further exhumation of the ultrahigh pressure metamorphic rocks in the Dabie Mountains.

关键词： Dabie orogen, granulite, zircon U-Pb ages, Sm-Nd age.