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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 china, Hefei 23.026, china 2. The Key Laboratory of Continental Dynamics of the Ministry of Education, Northwest University, Xi’an 710069, china 3. Faculty of Earth Sciences, china University of Geosciences, Wuhan 43.074, china School of Earth and Space Sciences University of Science and Technology of China Hefei China The Key Laboratory of Continental Dynamics of the Ministry of Education Northwest University Xi’an China Faculty of Earth Sciences China University of Geosciences 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 123.127 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.

Re-Os(ICP-MS)dating of the massive sulfide ores from the Jinchuan Ni-Cu-PGE deposit

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Science china Earth Sciences 2005年第10期48卷 1672-1677页

作者： YANG Gang1,2, DU Andao1, LU Jiren3. QU Wenjun1 & CHEN Jiangfeng2 1. National Research center of Geoanalysis, Beijing 10003., china 2. Laboratory for Earth Material Cycling, School of Earth and Space Sciences, University of Science and Technology of china, Hefei 23.026, china 3. Institute of Mineral Resource, Chinese Academy of Geological Sciences, Beijing 10003., china National Research center of Geoanalysis University of Science and Technology of china Chinese Academy of Geological Sciences

Massive sulfide ore from the Jinchuan Ni-Cu-PGE deposit was dated by Re-Os technique using Carius Tube digestion, Os distillation, Re extraction by acetone and ICP-MS measurement. An isochron giving an age of 83. ± 3. Ma, initial 187Os/188Os ratio of 0.279 ± 0.018 (MSWD = 1.7) and γOs = 13. ± 15 is obtained. The Re-Os age obtained agrees, within analytical uncertainties, with previous shrimp zircon U-Pb age of 827 ± 8 Ma (n=5, MSWD = 4.3.. The result suggests that the deposit was formed at Neoproterozoic and that the formation of the Jinchuan Ni-Cu-PGE sulfide deposit may be closely related to the plume activity, which were attributed to the breakup of the Rodinia supercontinent. The high γOs of the massive ores sug-gests that crustal material was involved in the formation of the Jinchuan deposit, however, the quantity of the added crustal material is less than 10%.

关键词： Jinchuan Ni-Cu-PGE deposit, Re-Os dating, ICP-MS.

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 {3., Beijing 10003., china 4. Institute of Geology, Chinese Academy of Geological Sciences, Beijing 10003., china Geological Surveying Institute of Hainan Haikou China Institute of Geomechanics Chinese Academy of Geological Sciences Beijing China Beijing center of shrimp Beijing China Institute of Geology Chinese Academy of Geological Sciences 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/23.U ages of 3.8±3.5 Ma (of granite, 95% confidence level, MSDW=1.23. and 3.2.9±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.

shrimp U-Pb dating and Hf isotopic analyses of Middle Ordovician meta-cumulate gabbro in central Qiangtang, northern Tibetan Plateau

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Science china Earth Sciences 2010年第5期53卷 657-664页

作者： ZHAI QingGuo1 WANG Jun1, LI Cai2 & SU Li3.1 Institute of Geology, Chinese Academy of Geological Sciences, Beijing 10003., china 2 College of Earth Sciences, Jilin University, Changchun 13.061, china 3.The Geological Laboratory {3. and State Key Laboratory of Geological Processes and Mineral Resources, china University of Geo- sciences, Beijing 100083. china Institute of Geology Chinese Academy of Geological Sciences Beijing China College of Earth Sciences Jilin University Changchun China The Geological Laboratory center and State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing China

Metabasites consisting of metamorphic ultra-mafic rocks, cumulate gabbro, gabbro (diabase), basalt, and plagiogranite are exposed at the Taoxinghu area in central Qiangtang, northern Tibetan Plateau. Zircon shrimp U-Pb dating for the cumulate gabbro yields a weighted mean age of 467±4 Ma, which is the oldest and most reliable magmatic age in this area. Zircon 176Hf/177Hf ratios range from 0.282615 to 0.282657, with εHf(t) values of 5.02±0.28, indicating that the cumulate gabbro was mainly derived from the depleted mantle. In addition, geochemical data of metabasites suggest that they have similar characteristics to those in the mid-ocean ridge basalts (MORB). The Taoxinghu metabasites may represent the fragment of Early Paleozoic ophiolite in the "Central Uplift" of the Qiangtang, northern Tibetan Plateau.

关键词： Qiangtang cumulate gabbro shrimp dating Hf isotope

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虾仁热物性的计算及冻结时间的数值模拟

食品与机械 2018年第2期34卷 106-110页

作者：唐婉谢晶王金锋周洪剑上海海洋大学上海201306 上海水产品加工与贮藏工程技术研究中心上海201306 上海冷链装备性能与节能评价专业技术服务平台上海201306 上海201306 上海宝丰机械制造有限公司上海201306

在虾仁热物性参数计算和等效比热容处理潜热的基础上,采用有限差元法对不规则虾仁建模,分别预测虾仁对称截面距冰箱冷冻层底部15,50,100mm处的冻结时间,在该基础上,对冰箱冻结虾仁进行实验验证。通过数值模拟与实验验证结果的对比发现,... 详细信息

在虾仁热物性参数计算和等效比热容处理潜热的基础上,采用有限差元法对不规则虾仁建模,分别预测虾仁对称截面距冰箱冷冻层底部15,50,100mm处的冻结时间,在该基础上,对冰箱冻结虾仁进行实验验证。通过数值模拟与实验验证结果的对比发现,模拟冻结时间与实验冻结时间曲线相关系数为0.996,虾仁切面中心测点的最大误差值为1.85K,说明该数值模拟方法可以有效预测食品冻结过程中温度分布,对虾仁的冷冻加工、品质控制以及设备的优化具有重要意义。

关键词：数值模拟冻结时间食品冻结温度场

shrimp Zircon U-Pb Ages and Geochemical Characteristics of the Neoproterozoic Granitoids in the Huangling Anticline and Its Tectonic Setting

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Journal of Earth Science 2012年第5期23卷 659-675页

作者：魏运许彭松柏蒋幸福彭中勤彭练红李志宏周鹏曾雄伟 Wuhan Institute of Geology and Minerals Resources Wuhan Center of Geological Survey Faculty of Earth Sciences China University of Geosciences Three Gorges Research center for Geo-hazard Ministry of EducationChina University of Geosciences State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences

shrimp zircon U-Pb dating of the Neoproterozoic Maoping （茅坪） series （Sandouping （三斗坪） rock suite） granites exposed in the southern part of the Huangling （黄陵） anticline shows that the formation time of Sandouping biotite-hornblende tonalite intrusion, Jinpansi （金盘寺） hornblende-biotite tonalite intrusion, and Longtanping （龙潭坪） monzogranite are 863.9, 842±10, and 844±10 Ma, respectively. Their geochemical features include A/CNK=0.98-1.06, from metaluminous to weakly peraluminous, δ=1.3.-1.53. Sm/Nd=0.17-0.24, and RbN/YbN=1.1-3.62. These indicate that the granite rocks are supersaturated SiO2 calc-alkaline granitoids. The characteristic of Sr-Nd isotopic composition is that the values of εNd（t） and εsr（t） are -12.4 to -11.0 and 20.2-3..2, respectively. It also suggests that the material source of the granite rocks mainly originated from the crust, and they formed in a volcanic arc tectonic environment. These facts suggest that the occurrence of Neoproterozoic granitoids in the southern part of the Huangling anticline should be related to an arc environment along an active continental margin caused by southward subduction of oceanic crust beneath the northern Yangtze craton, and the formation age is not later than 863.Ma.

关键词： Huangling anticline Yangtze plate Neoproterozoic granitoid shrimp zircon U-Pbdating geochemistry tectonic setting.

Status and Prospect of Crop Rotation of Procambarus Clarkii and Mid-season Rice in china

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Status and Prospect of Crop Rotation of Procambarus Clarkii ...

Detrital Zircons Transported from North china to Yangtze in the Middle Paleozoic:Implications for Tectonic Evolution in Central china

2010 3.d International Conference on Future BioMedical Information Engineering (FBIE 2010)

作者： Luojun Gong1 2 3.4 Xinya Shu2 and Congyi Zhang2 1College of Fisheries Huazhong Agricultural University Shizishan Road 1# Wuchang District Wuhan china 2Hubei Provincial Fisheries Research Institute Wuhan china Bangxi Xiong1 Lansong Yang3.Qianhong Gu1and JieChen1 3.ubei Provincial Fishery Technical Extension center Pengliuyang Road 23.# Wuchang District Wuhan china 4 Wuhan Water & Sky Biology-Environmental Engineering co. ltd Luoshi South Road 519# Hongshan District Wuhan china

The paper gives an introduction to transformation of Procambarus Clarkii from being killed before to being applied and developed now, and the historical background of development of crop rotation technology of Procambarus Clarkii and mid-season rice in china. It focuses on crop rotation technology of Procambarus Clarkii and mid-season rice in china, involving environmental conditions of paddy field, engineering construction, placing mode of parent shrimps, placing mode of young shrimps, aquaculture management of adult shrimps, fishing and disease control. Besides, the paper discusses the present status and prospect of crop rotation of Procambarus Clarkii and mid-season rice in china, and the main contents include: first, the market demand is large, thus crop rotation of Procambarus Clarkii and mid-season rice will continue growing fast;second, the total yield increases each year, and sales price maintains steady and decreases gradually;third, the production cost is continuously raised each year, and the comparative benefit is reduced gradually;fourth, to improve the quality of shrimp species and guarantee supply of fingerlings;fifth, to develop high-quality baits and research bait casting technique;sixth, to pay great attention to diseases and improve aquaculture environment;seventh, to strengthen scientific research and develop aquaculture mode.

关键词： Procambarus Clarkii Crop Rotation Status and Prospect Mid-season Rice

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Detrital Zircons Transported from North China to Yangtze in ...

长江下游水生动物群落生物多样性变动趋势初探

中国矿物岩石地球化学学会第十届学术年会

作者： SHE Zhen-bing,MA Chang-qian ,WAN Yu-shengState Key Laboratory of Geological Processes and Mineral Resource, and Faculty of Earth sciences, china University of Geosciences, Wuhan 43.074,china Beijing shrimp {3., Beijing 10003.,china

＜正＞ The Qilian-Qinling-Dabie Orogen, the so-called Central china Orogenic Belt, presents the largest exposure of ultra-high pressure/ high pressure metamorphic rocks in the world. Being the most important geological boundary in china, it separates the North china Block （NCB） from the South china Block （SCB）. However, the timing of the amalgamation of the North and South

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水生生物学报 2002年第6期26卷 654-661页

作者：施炜纲王博王利民中国水产科学研究院淡水渔业研究中心无锡214081 中国科学院水生生物研究所

对 1 990— 1 999年间长江下游江段生物多样性的变动趋势进行了研究 ,并就群落稳定性与多样性的关系进行了探讨。结果表明 :物种多样性指数量大值为 1 .1 1 1 2 ;最小值为 0 .0 3. 7。反映物种均匀度、丰盛度的指数都有不同程度的下降 ... 详细信息

对 1 990— 1 999年间长江下游江段生物多样性的变动趋势进行了研究 ,并就群落稳定性与多样性的关系进行了探讨。结果表明 :物种多样性指数量大值为 1 .1 1 1 2 ;最小值为 0 .0 3. 7。反映物种均匀度、丰盛度的指数都有不同程度的下降 ,而反映优势度的指数却有一定程度的上升 ,优势度指数最大值为 1 ;最小值为 0 .3.0 4 6,优势种前 6位分别为杂虾、青虾、餐条、吻、蛇、黄颡。表明长江下游江段的生物多样性正在逐步丧失。经济鱼类数量趋减 ,小型野杂鱼类数量趋增。

关键词：长江下游水生动物群落生物多样性变动趋势