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U-Pb dating of zircon from the bed parallel anatectic granitic intrusion in the Baoban group in Hainan Island and the tectonic implication

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Science china Earth sciences 2005年第12期48卷 2092-2103页

作者： DING Shijiang1, HU Jianmin2, SONG Biao3,4, CHEN Mulun1, XIE Shengzhou1 & FAN Yuan1 1. Geological Surveying institute of Hainan, haikou 570206, china 2. institute of Geomechanics, chinese academy of Geological sciences, Beijing 100081, china 3. Beijing Center of SHRIMP, Beijing 100037, china 4. institute of Geology, chinese academy of Geological sciences, Beijing 100037, china 1. Geological Surveying institute of Hainan 570206 Haikou China 2. institute of Geomechanics Chinese Academy of Geological Sciences 100081 Beijing China 3. Beijing Center of SHRIMP 100037 Beijing China 4. institute of Geology Chinese Academy of Geological Sciences 100037 Beijing China

The petrological and geochemical features of the bed parallel granitic intrusion in the Pre-Cambrian Baoban group in Hainan Island attest to the anatexis origin of the granites. U-Pb dating analyses of zircons from the anatectic granite and the biotite two-feldspar gneiss in the Baoban group, using SHRIMP II in the Beijing Ion-probe Center, acquire 206Pb/238U ages of 368±3.5 Ma (of granite, 95% confidence level, MSDW=1.23) and 362.9±6.1 Ma (of gneiss, 95% confidence level, MSDW = 2.04) respectively. The two late Devonian ages indicate consistently a tectonic- thermal event experienced in Hainan Island, and are the first discovered record of the Devonian geological process in the district. This event possibly resulted from the deep ther-mal-dynamic process when the Gondwana continent began to break up in the Devonian period.

关键词： Hainan Island, Devonian period, anatectic granite, zircon SHRIMP U-Pb dating.

Can soil organic carbon sequestration and the carbon management index be improved by changing the film mulching methods in the semiarid region?

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Journal of Integrative Agriculture 2024年第5期23卷 1541-1556页

作者： Jialin Yang Liangqi Ren nanhai Zhang Enke Liu Shikun Sun Xiaolong Ren Zhikuan Jia Ting Wei Peng Zhang College of Agronomy Northwest A&F UniversityYangling 712100China Key laboratory of Crop Physi-Ecology and Tillage Science in Northwestern Loess Plateau Ministry of Agriculture and Rural AfairsNorthwest A&FUniversityYangling 712100China institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural SciencesBeijing 100081China College of Water Resources and Architectural Engineering Northwest A&F UniversityYangling 712100China

Plastic film mulching has been widely used to increase maize yield in the semiarid area of ***, whether long-term plastic film mulching is conducive to agricultural sustainability in this region remains controversial.A field experiment was initiated in 2013 with five different film mulching methods:(i) control method, flat planting without mulching (CK),(ii) flat planting with half film mulching (P),(iii) film mulching on ridges and planting in narrow furrows(S),(iv) full film mulching on double ridges (D), and (v) film mulching on ridges and planting in wide furrows (R).The effects on soil organic carbon (SOC) content, storage, and fractions, and on the carbon management index (CMI)were evaluated after nine consecutive years of plastic film *** results showed that long-term plastic film mulching generally maintained the initial SOC *** with no mulching, plastic film mulching increased the average crop yield, biomass yield, and root biomass by 48.38, 35.06, and 37.32%, respectively, which led to the improvement of SOC ***, plastic film mulching significantly improved CMI, and increased the SOC content by 13.59%, SOC storage by 7.47%and easily oxidizable organic carbon (EOC) by 13.78%on average,but it reduced the other labile *** sequestration and CMI were improved by refining the plastic film mulching *** S treatment had the best effect among the four mulching methods, so it can be used as a reasonable film mulching method for sustainable agricultural development in the semiarid area.

关键词： plastic film mulching soil organic carbon labile organic carbon fractions semiarid area

Novel alleles among soybean Bowman-Birk proteinase inhibitor gene families

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Science china(Life sciences) 2008年第8期51卷 687-692页

作者： WANG YuePing1,2, CHEN XiongTing2 & QIU LiJuan1 1 National Key Facility for Crop Gene Resources and Genetic Improvement, Key laboratory of Crop Germplasm & Biotechnology(MOA)/institute of Crop Science, chinese academy of Agricultural sciences, Beijing 10008, china 2 institute of Tropical Biotechnology, chinese academy of Tropical Agricultural sciences, haikou 571101, china 1. National Key Facility for Crop Gene Resources and Genetic Improvement Key Laboratory of Crop Germplasm & Biotechnology (MOA)/Institute of Crop Science Chinese Academy of Agricultural Sciences Beijing 10008 China 2. institute of Tropical Biotechnology Chinese Academy of Tropical Agricultural Sciences Haikou 571101 China

Trypsin inhibitors have been found in various animals, plants and *** were two types of trypsin inhibitors in soybean including Bowman-Birk protease inhibitors(BBI) and Kunitz in-hibitors(KTI).The different BBI genes from wild soybean(***) and cultivated soybean(***) formed a multigene *** constructed a cDNA library of cultivar 'SuiNong 14' seed at the R7 growth stage using the SMART *** contigs or singletons were highly homologous to soy-bean protease *** of 5, 35, 8 and 9 were highly homologous to BBI family members BBI-A1, BBI-A2, BBI-C and BBI-D, *** analyses showed there were novel allelic varia-tions among the 4 BBI members in SuiNong *** on the comparison of soybean seed cDNA li-braries from different developmental stages, it was apparent that the expression of trypsin inhibitors increased during seed development in *** analysis of BBI gene sequences among dicotyledonous and monocotyledonous plants demonstrated that these genes shared a common pro-genitor.

关键词： soybean trypsin inhibitor Bowman-Birk proteinase inhibitor Kunitz trypsin inhibitor allelic variation

A hybrid scheme for geoacoustic inversion

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chinese Journal of acoustics 2010年第2期29卷 162-170页

作者： ZHANG Xuelei LI Zhenglin HUANG Xiaodi National laboratory of acoustics Institute of Acoustics Chinese Academy of Sciences Beijing 100190 Graduate University of chinese academy of sciences Beijing 100190 Research institute of TV and Electro-acoustics Beijing 100015 haikou laboratory of acoustics Institute of Acoustics Chinese Academy of Sciences Haikou 570105

A hybrid inversion scheme of geoacoustic parameters, which combines dispersion characteristics of normal modes with transmission loss, has been proposed based on the facts that different parameters have different effects on sound field. First, considering the dispersion characteristics of normal modes were sensitive to the density and the sound speed of seabottom, and not sensitive to the seabottom attenuation coefficient, the group time delays of different modes and different frequencies were acquired through adaptive optimal kernel time-frequency representation, then the group time delays were taken as the cost function, and using a global optimal algorithm, the seabottom density and the profile of seabottom sound speed were deduced. Successively, the validity of inversion results was evaluated by the a posteriori probability. Last, the attenuation coefficient of sediment is inverted using the transmission loss data recorded from the ship radiation noise. The validity of the total inversion results has been evaluated by making use of the matched field processing source localization.

关键词： mode A hybrid scheme for geoacoustic inversion VGS

Adaptive nonlinear prediction of ocean reverberation

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chinese Journal of acoustics 2009年第3期28卷 252-261页

作者： GAN Weiming LI Fenghua National laboratory of acoustics Institute of Acoustics Chinese Academy of Sciences Beijing 100190 haikou Lab Institute of Acoustics Chinese Academy of Sciences Haikou 570105

An adaptive nonlinear prediction algorithm is proposed to predict ocean reverberation based on the phase space reconstruction of nonlinear dynamic system. The prediction algorithm is tested by experimental reverberation data measured in two areas, and the one-step forward prediction results are in good agreement with the experimental data. If the errors between the predicted and experimental data are chosen as the variable to detect the target in the reverberation series, the reverberation is suppressed and the signal-to-reverberation ratio is improved.

关键词： data

Simulating a typhoon storm surge in the East Sea of china using a coupled model

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Progress in Natural Science:Materials International 2009年第1期19卷 65-71页

作者： Baoshu Yin a,Zhenhua Xua,b,Yong Huanga,b,Xiang Linc a institute of Oceanology,chinese academy of sciences,7# nanhai Road,Qingdao 266071,china b Graduate School of chinese academy of sciences,Beijing 100039,china c Traffic and Ocean Engineering College,Hohai University,Nanjing 210098,china [a]institute of Oceanology Chinese Academy of Sciences 7# Nanhai Road Qingdao 266071 China [b]Graduate School of Chinese Academy of Sciences Beijing 100039 China [c]Traffic and Ocean Engineering College Hohai University Nanjing 210098 China

A coupled numerical model with a 20 20 resolution grid has been developed and used to simulate five typical typhoon storm surges(5612,7413,7910,8114,and 9711) in the East Sea of *** main driving forces have been considered in this coupled model:wave radiation stress,combined wave-current bottom shear stress and wave-state-dependent surface wind *** model has then been compared with in situ measurements of the storm *** effect of different driving force components on the total storm surge has also been *** study has found that the coupled model with high resolution is capable of simulating the five typical typhoons better than the uncoupled models,and that the wave-dependent surface wind stress plays an important role in typhoon storm surge-wave coupling in this area and can increase the storm set-up by 1 *** study of the five typhoon cases has shown that the general coupling effects could increase storm set-up by 20-32%.Thus,it is suggested that to predict typhoon storm surges in the East Sea of china,a storm surge-wave coupled model be adopted.

关键词： East Sea of china Coupled model Typhoon storm surges Wave effects

The effects of the internal waves on temporal correlation of matched-field processing in shallow water

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chinese Journal of acoustics 2010年第1期29卷 23-32页

作者： JI Guihua LI Zhenglin DAI Qiongxin National laboratory of acoustics Institute of Acoustics Chinese Academy of Sciences Beijing 100190 haikou Lab Institute of Acoustics Chinese Academy of Sciences Haikou 570105 Graduate University of chinese academy of sciences Beijing 100190

Effects of linear and solitary internal waves on the temporal correlation of matched- field processing （MFP） in shallow water are numerically investigated for acoustic sources with different frequencies and depths based on oceanographic data from an experiment. It is shown that the temporal correlation of MFP decreases as the amplitude of solitary internal waves or the average energy density of linear internal waves increases. For acoustic source with lower frequency or located below the thermocline, the temporal correlation of MFP is less affected by internal waves, and the temporal correlation length of MFP is longer. Moreover, the effects of the range from solitary internal waves to acoustic source on the temporal correlation of MFP are relatively small.

关键词： The effects of the internal waves on temporal correlation of matched-field processing in shallow water MFP

Serpentinization of peridotites from the southern Mariana forearc

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Progress in Natural Science:Materials International 2009年第10期19卷 1287-1295页

作者： Xiaomei Wang a,b,Zhigang Zenga,Junbing Chenc a Key laboratory of Marine Geology and Environment,institute of Oceanology,chinese academy of sciences,7 nanhai Road,Qingdao 266071,china b Graduate School of chinese academy of sciences,19 Yuquan Road,Beijing 100049,china c Geological Brigade of Hydrogeology and Engineering Geology,Zhejiang Geological Prospecting Bureau,206 Baoshan Road,Ningbo 315012,china [a]Key laboratory of Marine Geology and Environment Institute of Oceanology Chinese Academy of Sciences 7 Nanhai Road Qingdao 266071 China [b]Graduate School of chinese academy of sciences 19 Yuquan Road Beijing 100049 China [c]Geological Brigade of Hydrogeology and Engineering Geology Zhejiang Geological Prospecting Bureau 206 Baoshan Road Ningbo 315012 China

A detailed petrologic and mineralogic study was carried out on serpentinized peridotites dredged from the southern landward slopes of the Mariana Trench,in order to reveal the serpentinization process of these unusual rocks and to identify the sole presence of the mineral *** constituent minerals of these southern Mariana forearc peridotites are olivine,amphibole and spinel,as well as serpentine,chlorite and *** with serpentinite seamounts,the serpentinized peridotites from the southern Mariana forearc are characterized by the absence of magnetite and brucite,and the common presence of talc;besides,the serpentine mineral variety is simplex,only *** mineral chemistry and mineral phase relationships,we conclude that(1) the absence of magnetite in the serpentinized peridotites is due to incomplete serpentinization,other than magnetite,the iron end-member in olivine forms Ferich brucite and Fe-rich serpentine;(2) brucite is not stable with high silica activity,reacting with later SiO2-rich fluid and then forming lizardite,leading to a lack of brucite in these serpentinized peridotites;(3) the occurrence of talc is the result of later SiO2-rich fluid reactions with lizardite;and(4) the reason for the sole occurrence of lizardite is that the temperature condition of our study are awas nothig henough for the formation of antigorite(whichisstable at >500 °C).Despite the broad overlap of lizardite and chrysotile in growth temperature,differences in the modes of occurrence of lizardite and chrysotile,such as the scarcity of H2O,low porosity and permeability,as well as the actual situation of initial serpentinization in the study area,result in the absolute prevalence of lizardite over chrysotile in the area.

关键词： Peridotite Serpentinization Mineral chemistry Lizardite Mariana

Evidence for metasomatic mantle carbonatitic magma extrusion in Mesoproterozoic ore-hosting dolomite rocks in the middle Kunyang rift, central Yunnan, china

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Progress in Natural Science:Materials International 2008年第8期18卷 965-974页

作者： Yongbei Zhanga,b,c, Hua Bia,*, Longshi Yua, Shihua Sunc, Jiaxiang Qiub, Chengyan Xub, Hao Wang b, Renjing Wang b a The Department of Resources, Environment and Tourism, Hainan Normal University, No. 432, Yinpo Road, Longshepo, haikou 57000, china b Key laboratory of Mineral Resources, institute of Geology and Geophysics, chinese academy of sciences, Beijing 100029, china c Faculty of Earth sciences, china University of Geosciences, Wuhan 470074, china The Department of Resources Environment and Tourism Hainan Normal University No. 432 Yinpo Road Longshepo Haikou 57000 China Key laboratory of Mineral Resources Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Faculty of Earth sciences China University of Geosciences Wuhan 470074 China

The Kunyang rift lying on the western margin of the Yangtze platform is a rare Precambrian Fe-Cu mineralization zone. WudingLufeng basin that is an important part of the zone is located on the west edge in the middle of the rift. The most important ore-hosting rocks are Mesoproterozoic dolomite rocks in the basin controlled by a ring fracture system, which is a fundamental structure of the basin. Plenty of silicate minerals and acicular apatite, feldspar phenocrysts and small vesicular, flown line and flown plane structures, melt inclusion and high temperature fluid inclusion found in most ore-hosting dolomites suggest that this kind of rocks could not be sedimentary dolomite, marble or hydrothermal carbonate rocks. The Zr/Hf and Nb/Ta values of the rocks are identical with those of associated mantle-derived rocks, and vary widely. For the monomineral dolomite, d18OSMOW‰ = +5.99 to +18.4 and d13CPDB‰ = à3.01 to +0.94, which fall within the range for all carbonatitic volcanic rocks of the world. As for the accessory minerals, the values of d18OSMOW‰ of magnetite (=+3.47 to +5.99‰) are close to that of the mantle (34S‰ values of sul?des (à5.09 to +5.78, averaging +1.50) are close to that of meteorite. For all the ore-bearing dolomite rocks, eNd = +0.19 to +2.27, and the calculated ISr = 0.699143, while for the associated mantle-derived rocks, eNd = +3.18 to +3.72. All the data suggest that the mineral assemblage is not only igneous but also of metasomatic mantle origin. And the presence of acicular apatite indicates that the rocks were formed by magma rapidly cooling. And the phenocryst texture and vesicular, flown and ropy and pyroclastic structures suggest that the igneous rocks were extrusive. Therefore, the ore-bearing dolomite rocks are carbonatitic volcanic rocks. This conclusion implies that most iron and copper ore deposits hosted in the dolomite rocks should be of the carbonatite type.

关键词： Central Yunnan Kunyang rift Precambrian Mineralization Carbonatitite Volcanic rocks Petrogenesis Iron and copper ore deposit