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Chinese Physics B 2024年第8期33卷 526-543页

作者：徐兆文白雪马健万壮壮王超群 Laser Institute Qilu University of Technology(Shandong Academy of Sciences)Jinan 250104China

Quantitative relationship between nanosecond pulsed laser parameters and the characteristics of laser-generated ultrasonic waves in polycrystalline materials was *** high energy of the pulsed laser with a large irradiation spot simultaneously generated ultrasonic longitudinal and shear waves at the epicenter under the slight ablation *** optimized denoising technique based on wavelet thresholding and variational mode decomposition was applied to reduce noise in shear waves with a low signal-to-noise *** approach for characterizing grain size was proposed using spectral central frequency ratio(SCFR)based on time-frequency *** results demonstrate that the generation regime of ultrasonic waves is not solely determined by the laser power density;even at high power densities,a high energy with a large spot can generate an ultrasonic waveform dominated by the thermoelastic *** is ascribed to the intensification of the thermoelastic effect with the proportional increase in laser irradiation spot area for a given laser power ***,both longitudinal and shear wave SCFRs are linearly related to grain size in polycrystalline materials;however,the shear wave SCFR is more sensitive to finer-grained *** study holds great significance for evaluating metal material properties using laser ultrasound.

关键词： laser-ultrasonics polycrystalline materials ultrasonic time-frequency characteristics grain size

Geological and Geochemical Characteristics and Genesis of the Shaxi Porphyry Copper (Gold) Deposits, Anhui Province

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Acta Geologica Sinica(English Edition) 1999年第1期73卷 8-18页

作者： xu zhaowen QIU Jiansheng REN Qijiang xu Wenyi NIU Cuiyi FU Bin Department of Earth Sciences Nanjing University Nanjing Jiangsu 210093 Department of Earth and Space Sciences University of Science and Technology of China Hefei Anhui 230026

The Shaxi porphyry copper (gold) deposits are a typical example of porphyry copper deposits associated with diorite in eastern China. Quartz diorite, which hosts the deposits, has a Rb-Sr isochron age of 127.9 ± 1.6 Ma. Geochemically, the rock is rich in alkalis (especially sodium), light rare earth elements (LREE) and large-ion lithophile elements (LILE), and has a relatively low initial strontium isotopic ratio (Isr=0.7058); thus it is the product of differentiation of crust-mantle mixing source magma. The model of alteration and mineralization zoning is similar to the Hollister (1974) diorite model. The ore fluids have a relatively high salinity and contain significant amounts of CO2, Ca2+, Na+ and ***CI?. The homogenization temperatures of fluid inclusions for the main mineralization stage range from 280 to 420°C, the δ18O values of the ore fluids vary from 3.51 to 5.52 %, the δD values are in the range between ?82.4 and ?59.8 %, the δ34S values of sulphides vary from ?0.3 to 2.49 %, and the δ13C values of CO2 in inclusions range between ?2.66 and ?6.53 %. Isotope data indicate that the hydrothermal ore fluids and ore substances of the Shaxi porphyry copper (gold) deposits were mainly derived from magmatic systems.

关键词： geological and geochemical characteristics genesis of the deposit porphyry copper (gold) deposit Shaxi Anhui

Integrated data-model-knowledge representation for natural resource entities

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International Journal of Digital Earth 2022年第1期15卷 653-678页

作者： Yulin Ding zhaowen xu Qing Zhu Hankan Li Yan Luo Ying Bao Lingjun Tang Sen Zeng Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengduPeople's Republic of China Municipal Planning & Land Estate Information Center Shenzhen Municipal Bureau of Planning and Natural ResourcesShenzhenPeople's Republic of China Information Center Department of Natural Resources of Sichuan ProvinceChengduPeople's Republic of China

The unified management and planning of national or provincial natural resources distributed both aboveground and underground have become increasingly *** depictions of natural resource elements and their interactions are key to achieving integrated and systematic management of natural ***,current spatiotemporal data models are based only on data descriptions,attribute records,and other model knowledge of a more general basis,without intuitively describing relationships between these elements and natural *** paper,therefore,proposes an integrated data-model-knowledge representation model to explicitly describe the time,space,and interaction of natural resource entities through an integrated knowledge ***,this study constructs a conceptual model using the aspects of semantics,scale,and data-model-knowledge,thereby explicitly describing the relationships of natural ***,a logical model of natural resource representation is proposed,that is integrated with time,space,attributes,and ***,taking the management of water resources as an example,this paper realizes the meticulous presentation of the levels of detail and rich semantic relations of natural resource *** findings of this study lay the foundation for a more efficient,precise,and lucid perception of the distribution laws and complicated interactional relationships of natural resources,both aboveground and underground.

关键词： Natural resources data-model-knowledge interactional relationships

Characteristics and metallogenesis of epithermal gold (copper)deposits in the middle-south parts of Tancheng-Lujiang deep fault zone and its vicinity, eastern China

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Chinese Science Bulletin 1999年第S2期44卷 63-65页

作者： QIU Jiansheng and xu zhaowen Department of Earth Sciences, Nanjing University, Nanjing 210093, China Department of Earth Sciences Nanjing University Nanjing 210093 China

EPITHERMAL gold (copper) deposits distributed in the middle-south parts of Tancheng-Lujiang deep faultzone and its vicinity have close relation to Mesozoic shoshonitic magmatism. According to their metallogenic features and ore-forming conditions, these deposits can be divided into three types; tellurium-goldtype Au deposit, quartz-adularia type Au deposit and quartz-manganoansiderite type Au-Cu deposit. Therepresentative deposits of them are Guilaizhuang, Dongxi and Tiantoushan. In this note, the general features of the three typical epithermal gold (copper) deposits are outlined and the relationship between mineralization and types of volcanic basins is discussed preliminarily.

关键词： epithermal gold(copper) deposits metallogenesis eastern China.

Characteristics of Volcanic Rocks in the Shoshonite Province, Eastern China, and Their Metallogenesis

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Acta Geologica Sinica(English Edition) 1996年第3期70卷 246-259页

作者： Wang Dezi, Ren Qijiang, Qiu Jiansheng, Chen Kerong,xu zhaowen and Zeng Jiahu Department of Earth Sciences, Nanjing University, Nanjing, Jiangsu Department of Earth Sciences Nanjing University Nanjing Jiangsu

The shoshonite province in eastern China is characterized by extensive distribution (ca. 80000 km2) of Late Jurassic-Early Cretaceous (165-100 Ma) shoshonite series with subordinate high-K calc-alkali series. It was formed in a dominantly tensile stress field. In comparison with their analogues in island arcs and active continental margins in other countries, the volcanic rocks in the shoshonite province have their specific characteristics in petrology, mineralogy and geochemistry as well as related mineralization association, which are the comprehensive reflection of the special composition and structure of the mantle and crust of the province and the special Mesozoic regional tectonic setting.

关键词： shoshonite province regional tectonic setting isotopic composition mineralogical-petrological-geochemical characteristics eastern China

The Formation and Evolution of the Lujiang-Zongyang Volcano-Structural Depression in Anhui and Its Relation to Mineralization

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Acta Geologica Sinica(English Edition) 1993年第4期67卷 411-427页

作者： Ren Qijiang, Wang Dezi, xu zhaowen, Dong Huogen, Pan Longquan, Yang Rongyong, Fang Changquan and Hu Jin’an Department of Earth Sciences, Nanjing University, Nanjing, Jiangsu Fei Zhenbi Department of Earth Sciences Nanjing University Nanjing Jiangsu

The Lujiang-Zongyang volcano-structural depression resulted from the combined action of tectonism and volcanism. Its evolution progressed through five stages from 190 to 105 Ma B.P., during which nine types of metal and pyrite deposits were formed. These deposits show obvious regularities in the temporal-spatial distribution and have certain genetic relation, forming a minerogenetic series related to shoshonite within or around the volcano-structural depression on the basement that sank for a long period of time. This paper suggests a four-dimensional model of the formation and evolution of a typical volcano-structural depression and its related mineralizalion in a transition belt from the active margins to the inner part of a plate under alternating shear-compressive and shear-extensional stress conditions, but predominantly shear-extensional stress conditions.

关键词： Lujiang-Zongyang Anhui Province volcano-structural depression stress field mineralization four-dimensional model

Riverine sulfate sources and behaviors in arid environment,Northwest China:Constraints from sulfur and oxygen isotopes

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Journal of Environmental Sciences 2024年第3期137卷 716-731页

作者： Yifu xu Wenjing Liu Bing xu Zhifang xu Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China

The fate of riverine sulfate ion (SO_(4)^(2-)) and its environmental effects in arid environment are difficult to evaluate due to its complicated sources and strongly coupled behaviors with water cycle which is significantly modified by *** understand the sulfur cycle in aquatic systems in arid environment,the chemical and sulfur and oxygen isotopic compositions (δ^(34)S_(SO4)and δ^(18)O_(SO4)) of major rivers around the Badain Jaran Desert,northwestern China,were *** rivers had averaged SO_(4)^(2-)content at 1336μmol/L,over 10times higher than the global *** δ^(34)S_(SO4)and δ^(18)O_(SO4)values ranged from-5.3‰to+11.8‰and+1.6‰to+12.8‰,*** end-member analysis and the inverse model showed that riverine sulfate was mainly derived from evaporites dissolution (0-87%),sulfide oxidation (13%-100%) and precipitation (0-33%),indicating heterogeneity in sulfur sources and behaviors along the river drainage with the lithology variations and climate *** isotopic tools combining with hydro-chemistry compositions could be applied to reveal sulfur cycle in arid *** on the calculation,sulfide oxidation plays the primary role in the headwater and upstream in the Qilian-Mountains area,where sulfide is widely *** the proportion of evaporites dissolution contributing to riverine sulfate is much higher in downstream in a drier ***,less precipitation and higher temperature can lead to more intensive evaporation,affecting the process of sulfide oxidation and enhancing the rates of evaporites dissolution and sulfate precipitation in the basin.

关键词： Sulfur and oxygen isotopes Source apportionment Inverse model Arid environment Inland rivers Northwestern China

铜陵狮子山矿田大团山铜(钼)矿床流体包裹体研究

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高校地质学报 2016年第3期22卷 413-422页

作者：杨小男徐兆文王云健中国地质博物馆北京100034 内生金属矿床成矿机制研究国家重点实验室南京大学地球科学与工程学院南京210023

大团山铜（钼）矿床是安徽铜陵狮子山矿田内较为典型的岩浆热液叠加型铜钼矿床,其成因与早白垩世大团山石英二长闪长岩有密切关系.系统采集硫化物阶段的矿化石英脉并经岩相学显微观察发现,石英中捕获有大量的流体包裹体,主要分为三种类... 详细信息

大团山铜（钼）矿床是安徽铜陵狮子山矿田内较为典型的岩浆热液叠加型铜钼矿床,其成因与早白垩世大团山石英二长闪长岩有密切关系.系统采集硫化物阶段的矿化石英脉并经岩相学显微观察发现,石英中捕获有大量的流体包裹体,主要分为三种类型,即富气相（Ⅰ型）、富液相（Ⅱ型）的两相水溶液包裹体和含子晶的三相水溶液包裹体（Ⅲ型）.显微测温研究表明,流体包裹体的均一温度统计峰值分别出现在375-405°C和285-315°C之间,流体盐度的统计峰值出现在5.0wt.%-10.0 wt.%NaCleq.之间.激光拉曼探针分析表明,流体包裹体的气相成分以水蒸汽为主,含有少量CO2和CH4.流体氢、氧同位素组成呈岩浆流体特征.研究表明,大团山铜（钼）矿床的成矿流体主要来源于岩浆流体,在成矿过程中经历了相态变化,沸腾的流体体系受到了不均匀捕获.结合前人研究成果,狮子山矿田内早白垩世叠加改造型流体表现出同源特征,在物理化学演化方面具有一定规律性,流体的多次沸腾作用很可能对成矿元素的分配、迁移与沉淀起到了重要作用.

关键词：流体包裹体显微测温激光拉曼氢、氧同位素大团山铜(钼)矿床狮子山矿田

西大别白垩纪两阶段花岗岩成岩及钼成矿作用的讨论

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地球科学 2018年第12期43卷 4638-4650页

作者：陈伟毛景文徐兆文曲晓明于旸中国地质科学院矿产资源研究所自然资源部成矿作用和资源评价重点实验室北京100037 南京大学地球科学与工程学院江苏南京210093 自然资源部经济研究院河北廊坊065200

系统总结西大别白垩纪赋钼花岗岩的岩石成因,并结合这些岩体的岩石地球化学特征对西大别钼矿床形成条件进行探讨,对认识西大别钼成矿带的地球化学动力学背景具有重要意义.在白垩纪时期,西大别含钼花岗岩成岩作用与东大别地区相似,可分... 详细信息

系统总结西大别白垩纪赋钼花岗岩的岩石成因,并结合这些岩体的岩石地球化学特征对西大别钼矿床形成条件进行探讨,对认识西大别钼成矿带的地球化学动力学背景具有重要意义.在白垩纪时期,西大别含钼花岗岩成岩作用与东大别地区相似,可分为早、晚两个阶段.早阶段岩体(早于132Ma)形成于加厚地壳环境,晚阶段岩体(晚于130Ma)形成于非加厚地壳环境.这种岩石成因上的差别是导致该地区钼矿成矿条件差异的根本原因.结合钼元素的地球化学属性和中央造山带的演化特征,认为晚古生代时期位于造山带南侧的古秦岭洋可能为地壳中Mo元素在表生风化过程中提供有利的沉积环境,并且在三叠纪时期伴随扬子板块一起俯冲到华北板块之下,富钼沉积物与扬子地壳一起部分熔融形成富钼的岩浆,最终形成西大别白垩纪时期大规模的含钼成岩作用.

关键词：西大别造山带加厚下地壳钼成矿作用白垩纪花岗岩岩石学

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再生塔出口二氧化碳含量低的原因分析及对策

四川化工 2013年第6期16卷 26-28页

作者：许召文河南煤业化工集团中原大化公司河南濮阳457004

阐述苯菲尔法再生塔运行现状,分析二氧化碳纯度达不到设计值的原因,提出相应的解决措施。

关键词：苯菲尔法再生塔二氧化塔纯度过滤