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Geochemical Characteristics and Genesis of the Luxi-Xianrenzhang Diabase Dikes in Xiazhuang Uranium Orefield, Northern Guangdong Province

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Acta Geologica Sinica(English Edition) 2005年第4期79卷 497-506页

作者： LING Hongfei shen weizhou DENG Ping JIANG Shaoyong JIANG Yaohui YE Haimin PU Wei TAN Zhengzhong State Key Laboratory of Mineral Deposit Research and Department of Earth Sciences Nanjing University Nanjing Jiangsu 210093 Research Institute No. 290 CNNC Shaoguan Guangdong 512026

The Luxi-Xianrenzhang diabase dikes were emplaced into the eastern part of the Guidong composite granitoids in northern Guangdong Province at the end of the Early Cretaceous. They show tholeiitic features, enrichment in large ion lithophile elements, slight enrichment in light rare earth elements, depletion in Zr and Hf, and basically no depletion in Nb and Ta and no Eu anomaly. They are similar to intraplate basalt in terms of trace element characteristics. They have high εNd（t） values （3.6-4.9）, initial ^87Sr/^86Sr ratios （0.70530-70641） and δ^18O values and Dupal anomaly of Pb isotope compositions. Their Sr-Nd, Pb-Sr, Pb-Nd and Pb-Pb isotopes plot between DMM and EMII, with Pb similar to EMII, Nd relatively close to DMM and Sr in between. This profile suggests that the diabase dikes studied were derived from partial melting of a mantle source that had been subjected to metasomatism by fluids originated from a subduction zone under a tectonic environment of crustal extension and lithosphere thinning in the late Yanshanian.

关键词： geochemistry main and trace elements Nd-Sr-Pb-O isotopes diabase dikes Guangdong

Isotope Geological Studies of Granite-Type Uranium Deposits in South China

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Acta Geologica Sinica(English Edition) 1988年第3期1卷 291-305页

作者： shen weizhou Zhang Zuhuan Zheng Bangtong Department of Geology, Nanjing University, Nanjing, Jiangsu Department of Geology Nanjing University Nanjing Jiangsu

The uranium-bearing granites in South China can be classified into two types. namely, syntectic type andtransformation type. A fairly systematic hydrogen, oxygen. carbon, sulfur isotopic study of uranium depositsrelated to these two types of granites has been carried out by the authors, and the results show that they haveobvious differences in such aspects as ore-forming and rock-forming ages. properties of ore-forming solutionsand source of ore-forming substances. The authors hold that the uranium deposits related to the syntectic typegranitoids are intimately connected with magmatism in time and space, whereas the uranium deposits relatedto the transformation type granites, though spatially linked up with uranium-bearing granites, should actuallyowe their formation to extension in the fault block movement in South China.

关键词： In Isotope Geological Studies of Granite-Type Uranium Deposits in South China

Sr, Nd and O Isotopic Studies on the Genesis of the Huashan Granite Complex

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Acta Geologica Sinica(English Edition) 1990年第1期64卷 41-54页

作者： Zhu Jinchu Li Xiangdong shen weizhou Wang Yinxi Yang Jiedong Department of Earth Sciences, Nanjing University, Nanjing, Jiangsu Department of Materials Analysis, Nanjing University, Nanjing, Jiangsu Jia Zhongpeng Department of Earth Sciences Nanjing University Nanjing Jiangsu China

Systematical Sr, Nd and O isotopic studies were made on the Huashan granite complex in Guangxi. Incombination with the studies of geological, petrological and geochemical data, it is believed that the complexconsists of granites of three stages. with different geneses and different source materials. They are not the prod-ucts of differentiation and evolution of one single consanguineous magma. Granites of the 1st stage are of theIndosinian syntectic type or I type, also derived from a mixed mantle-crustal source. Those of the 2nd stage areof the early Yanshanian syntectic type or I type. also derived from a mixed mantle-crustal source, and those ofthe 3rd stage are of the late Yanshanian transformed type or S type. derived from a crustal source.

关键词： Nd and O Isotopic Studies on the Genesis of the Huashan Granite Complex Sr

Nd, Sr and O Isotopic Study on Spilite-Keratophyre in Xiqiu,,Zhejiang Province, China

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Acta Geologica Sinica(English Edition) 1992年第2期66卷 165-176页

作者： shen weizhou Zhang Bangtong Ling Hongfei Lai Mingyian Yang Jiedong Tao Xiancong Department of Earth Sciences, Nanjing University, Nanjing, Jiangsu Modern Analysis Centre, Nanjing University, Nanjing, Jiangsu Department of Earth Sciences Nanjing University Nanjing Jiangsu China

Nd, Sr and O isotopic study on the spilite-keratophyre sequence in Xiqiu shows that its ∈_(Nd) values are inthe range of 4.02-5.26, and its ∈_(Sr) values, +1.4-2.6. According to the points of these data in the ∈_(Nd)-T,∈_(Sr)-T and ∈_(Nd)-∈_(Sr) diagrams, the spilite-keratophyre is interpreted as being slightly contaminated by crustalmaterials. Its δ^(18)O values are 3.9-5.0‰. The depletion of ^(18)O in the rocks resulted from the influence ofseawater hydrothermal alteration during or soon after the rock formation. Based on the isotopic characteristicsand available geochemical data, it is believed that the spilite-keratophyre was formed in the well-developedisland-arc environment during the Late Proterozoic subduction of the palaeo-Pacific plate beneath thesoutheastern margin of the Yangtze massif.

关键词： Sr and O Isotopic Study on Spilite-Keratophyre in Xiqiu China Zhejiang Province Nd

The Characteristics and Genetic Mechanism of Igneous Topazites in South China

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Acta Geologica Sinica(English Edition) 1996年第1期70卷 33-45,109页

作者： Liu Changshi, shen weizhou and Wang DeziDepartment of Earth Sciences, Nanjing U niversity, Nanjing, Jiang su Fei Zhenbi Department of Earth Sciences Nanjing U niversity Nanjing Jiangsu

Igneous topazites found recently in South China are closely associated with F-rich granites in time and space. They have a typical igneous porphyritic texture. The phenocrysts are topaz and quartz, while the groundmass consists mainly of prismatic or acicular topaz microlites and anhedral quartz. Compared with granites, topazites are rich in SiO2 (65.06%-81.12% ) and Al2O3 (13.01%-18.09%) but poor in MgO and Na2O and strongly peraluminous with A/NKC = 3.204-37.313. Geochemically, the rocks are evidently depleted in Sr and Ba, but enriched in Sn, W, Nb and F. The concentrations of Sn and partial W in the topazites are 1-2 orders of magnitude higher than the average of acid rocks. The F-riched granites related to the topazites in the area usually have much higher ISr (0.7103-0.7460) and δ18OQ‰ (9.5-14.24), but lower INdCT) (-4.8- 9.4). It suggests that the topazite is similar to S-type granites in genesis. Hydroxylated silicate melt inclusions, consisting of several grains of quartz and aqueous fluids, have been found in the quartz phenocrysts. The entrapment temperature of these inclusions is about 520℃.

关键词： topazite inclusion immiscibility

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电磁兼容辐射安全裕度测量的不确定度分析

通信电源技术 2023年第12期40卷 186-188页

作者：杨越沈韦舟武汉中原电子集团有限公司湖北武汉430205

深入分析了GJB1389A系统电磁兼容中辐射安全裕度项目的测试过程,以及各种不确定因素对测试结果的影响。在此基础上,构建了相应的不确定度评定数学模型,并对测量结果进行评定,以保证辐射安全裕度测量结果的有效性。

关键词：电磁兼容辐射安全裕度不确定度评定

Strongly peraluminous granites of Mesozoic in Eastern Nanling Range, southern China: Petrogenesis and implications for tectonics

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Science China Earth Sciences 2005年第2期48卷 165-174页

作者： SUN Tao, ZHOU Xinmin, CHEN Peirong, LI Huimin, ZHOU Hongying, WANG Zhicheng & shen weizhou Department of Earth Sciences, Nanjing University, Nanjing 210093, China Tianjin Institute of Geology and Mineral Resources, China Geological Survey, Tianjin 300170, China Department of Earth Sciences Nanjing University Nanjing China Tianjin Institute of Geology and Mineral Resources China Geological Survey Tianjin China

The strongly peraluminous granites (SPGs) of Eastern Nanling Range (ENR) are a characteristic of all bearing highly aluminous minerals, such as muscovite±Al-rich biotite±tourmaline±garnet, and lack of cordierite. In respect of petrography, geochemistry, Nd isotope, and single grain zircon U-Pb dating, the representative granite bodies of them are studied. The research shows that these granites were emplaced in two stages, namely 228－225 Ma BP and J2－3 159－156 Ma BP, belonging to Indosinian and early Yanshanian periods, respectively, and they have low εNd(t) values (-10.6－-11.1), high A/CNK, Rb/Sr ratios and tDM values (1887－1817 Ma), and REE's tetrad effect (TE1, 3=1.13－1.34). In comparison with related geology, petrology and chronology of granites in adjacent regions, it is suggested that Indosinian SPGs of ENR formed in the circumstance of post-collisional extension 20 Ma after the major collision of Indosinian Movement (258－243 Ma BP) in Indo-China Peninsula, and early Yanshanian SPGs formed in the background of back-arc extension setting controlled by paleo-Pacific tectonic domain, and J1, the interval of two stages, is the interim from Tethyan to Pacific tectonic domains in South China. These SPGs have similar geological and geochemical characteristics, because they all crystallized from the magma of partial melting of early Proterozoic metasedimentary rocks when the thickened crust (≤50 km) became thinning, decompression, and transmitting of water.

关键词： Nanling Range, strongly peraluminous granite, petrogenesis of granite, South China.

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RE102电场辐射发射测量不确定度评定

电子质量 2023年第7期 62-65页

作者：杨越沈韦舟周勇武汉中原电子集团有限公司武汉430205

较为深入地分析了影响GJB 151B—2013中RE102电场辐射发射项目测量结果的各种不确定度因素,构建了其不确定度评定的数学模型,并以现在主流的测试设备为参照,进行了测量结果的合成标准不确定度的计算。评定结果为实验室测试能力的提升和... 详细信息

较为深入地分析了影响GJB 151B—2013中RE102电场辐射发射项目测量结果的各种不确定度因素,构建了其不确定度评定的数学模型,并以现在主流的测试设备为参照,进行了测量结果的合成标准不确定度的计算。评定结果为实验室测试能力的提升和测量结果的准确度提供了有益的支撑。

关键词：电磁兼容测试 RE102 测量不确定度不确定度评定

大民屯凹陷沙河街组四段、三段层序特征及其与油气成藏条件之间的关系

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地球学报 2006年第1期27卷 57-62页

作者：孙素青沈渭洲南京大学地球科学系

根据层序地层学理论,将大民屯凹陷古近系划分为两个层序:层序Ⅰ相当于沙四段和沙三段,层序Ⅱ相当于沙一段和东营组。层序Ⅰ发育湖侵和高位两个体系域,高位体系域又分上、下两部分。依据对构造、物源、气候和湖平面变化等层序控制因素的... 详细信息

根据层序地层学理论,将大民屯凹陷古近系划分为两个层序:层序Ⅰ相当于沙四段和沙三段,层序Ⅱ相当于沙一段和东营组。层序Ⅰ发育湖侵和高位两个体系域,高位体系域又分上、下两部分。依据对构造、物源、气候和湖平面变化等层序控制因素的分析结果,总结了不同体系域与生、储、盖层之间的关系:生油层主要发育在湖侵体系域当中,也是古生界潜山油藏的区域盖层;储集层主要发育在下部高位体系域,为曲流河—三角洲—滨浅湖、半深湖沉积和冲积扇—扇三角洲—滨浅湖沉积;上部高位体系域底部发育另一区域性盖层。上述有利的生、储、盖组合在该区油气聚集过程中起了重要作用,潜山和下部高位域储集体是深化勘探的潜在目标区。

关键词：大民屯凹陷层序地层体系域生、储、盖组合