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Source Enrichment Control on the Scale of Magmatic-Hydrothermal W-Sn Mineralization:Insights from Triassic and Jurassic Magma Reservoirs in the Continental Crust,Xitian,South China
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作者 GUO Chunli Simon AWILDE +2 位作者 Coralie SIEGEL CHEN Zhenyu WU Shichong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第1期132-149,共18页
There are two factors,source composition and magmatic differentiation,potentially controlling W-Sn mineralization.Which one is more important is widely debated and may need to be determined for each individual deposit... There are two factors,source composition and magmatic differentiation,potentially controlling W-Sn mineralization.Which one is more important is widely debated and may need to be determined for each individual deposit.The Xitian granite batholith located in South China is a natural laboratory for investigating the above problem.It consists essentially of two separate components,formed in the Triassic at ca.226 Ma and Jurassic at ca.152 Ma,respectively.The Triassic and Jurassic rocks are both composed of porphyritic and fine-grained phases.The latter resulted from highlydifferentiated porphyritic ones but they have similar textural characteristics and mineral assemblages,indicating that they reached a similar degree of crystal fractionation.Although both fine-grained phases are highly differentiated with elevated rare metal contents,economic W–Sn mineralization is rare in the Triassic granitoids and this can be attributed to less fertile source materials than their Jurassic counterparts,with a slightly more enriched isotopic signature and whole-rockεNd(226 Ma)of−10.4 to−9.2(2σ=0.2)compared withεNd(152 Ma)of−9.2 to−8.2(2σ=0.2)for the Jurassic rocks.The initial W-Sn enrichment was derived from the metasedimentary rocks and strongly enhanced by reworking of the continental crust,culminating in the Jurassic. 展开更多
关键词 W-sn mineralization magma reservoir geometry crystal fractionation Xitian Triassic-Jurassic granitic batholith Nanling range south China
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Fine quantitative characterization of high-H2S gas reservoirs under the influence of liquid sulfur deposition and adsorption
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作者 LI Tong MA Yongsheng +3 位作者 ZENG Daqian LI Qian ZHAO Guang SUN Ning 《Petroleum Exploration and Development》 SCIE 2024年第2期416-429,共14页
In order to clarify the influence of liquid sulfur deposition and adsorption to high-H2S gas reservoirs,three types of natural cores with typical carbonate pore structures were selected for high-temperature and high-p... In order to clarify the influence of liquid sulfur deposition and adsorption to high-H2S gas reservoirs,three types of natural cores with typical carbonate pore structures were selected for high-temperature and high-pressure core displacement experiments.Fine quantitative characterization of the cores in three steady states(original,after sulfur injection,and after gas flooding)was carried out using the nuclear magnetic resonance(NMR)transverse relaxation time spectrum and imaging,X-ray computer tomography(CT)of full-diameter cores,basic physical property testing,and field emission scanning electron microscopy imaging.The loss of pore volume caused by sulfur deposition and adsorption mainly comes from the medium and large pores with sizes bigger than 1000μm.Liquid sulfur has a stronger adsorption and deposition ability in smaller pore spaces,and causes greater damage to reservoirs with poor original pore structures.The pore structure of the three types of carbonate reservoirs shows multiple fractal characteristics.The worse the pore structure,the greater the change of internal pore distribution caused by liquid sulfur deposition and adsorption,and the stronger the heterogeneity.Liquid sulfur deposition and adsorption change the pore size distribution,pore connectivity,and heterogeneity of the rock,which further changes the physical properties of the reservoir.After sulfur injection and gas flooding,the permeability of TypeⅠreservoirs with good physical properties decreased by 16%,and that of TypesⅡandⅢreservoirs with poor physical properties decreased by 90%or more,suggesting an extremely high damage.This indicates that the worse the initial physical properties,the greater the damage of liquid sulfur deposition and adsorption.Liquid sulfur is adsorbed and deposited in different types of pore space in the forms of flocculence,cobweb,or retinitis,causing different changes in the pore structure and physical property of the reservoir. 展开更多
关键词 high-H2s gas reservoir liquid sulfur adsorption and deposition pore structure physical property reservoir characterization
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Effects of physical parameter range on dimensionless variable sensitivity in water flooding reservoirs 被引量:8
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作者 Yu Hu Bai Jia Chun Li Ji Fu Zhou 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2006年第5期385-391,共7页
The similarity criterion for water flooding reservoir flows is concerned with in the present paper. When finding out all the dimensionless variables governing this kind of flow, their physical meanings are subsequentl... The similarity criterion for water flooding reservoir flows is concerned with in the present paper. When finding out all the dimensionless variables governing this kind of flow, their physical meanings are subsequently elucidated. Then, a numerical approach of sensitivity analysis is adopted to quantify their corresponding dominance degree among the similarity parameters. In this way, we may finally identify major scaling law in different parameter range and demonstrate the respective effects of viscosity, permeability and injection rate. 展开更多
关键词 Physical parameter range Dimensionless variable sensitivity analysis Water flooding reservoir Two-phase flow in porous media
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Reservoir Quality Assessment of the Upper Permian Chhidru Formation, Salt and Surghar Ranges, Pakistan
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作者 Muhammad ZAHIR Muhammad AWAIS +5 位作者 Mukhtiar GHANI Mohibullah MOHIBULLAH Osman SALAD HERSI Irfan U.JAN Sajjad AHMAD Hamid IQBAL 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2021年第6期2120-2137,共18页
The Late Permian succession of the Upper Indus Basin in northeastern Pakistan is represented by the carbonatedominated Zaluch Group, which consists of the Amb, Wargal and Chhidru formations, which accumulated on the s... The Late Permian succession of the Upper Indus Basin in northeastern Pakistan is represented by the carbonatedominated Zaluch Group, which consists of the Amb, Wargal and Chhidru formations, which accumulated on the southwestern shelf of the Paleo-Tethys Ocean, north of the hydrocarbon-producing Permian strata of the Arabian Peninsula. The reservoir properties of the mixed clastic-carbonate Chhidru Formation(CFm) are evaluated based on petrography, using scanning electron microscopy(SEM), energy dispersive x-ray spectroscopy(EDX) and x-ray diffraction(XRD) techniques. The diagenetic features are recognized, ranging from marine(isopachous fibrous calcite, micrite), through meteoric(blocky calcite-I, neomorphism and dissolution) to burial(poikilotopic cement, blocky calcite-II-III, fractures, fracture-filling, and stylolites). Major porosity types include fracture and moldic, while inter-and intra-particle porosities also exist. Observed visual porosity ranges from 1.5%–7.14% with an average of 5.15%. The sandstone facies(CMF-4) has the highest average porosity of 10.7%, whereas the siliciclastic grainstone microfacies(CMF-3) shows an average porosity of 5.3%. The siliciclastic mudstone microfacies(CMF-1) and siliciclastic wacke-packestone microfacies(CMF-2) show the lowest porosities of 4.8% and 5.0%, respectively. Diagenetic processes like cementation, neomorphism, stylolitization and compaction have reduced the primary porosities;however, processes of dissolution and fracturing have produced secondary porosity. On average, the CFm in the Nammal Gorge, Salt Range shows promise and at Gula Khel Gorge, Trans-Indus, the lowest porosity. 展开更多
关键词 sedimentary petrography DIAGENEsIs hydrocarbon reservoir CHANGHsINGIAN Chhidru Formation salt range surghar range Pakistan
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基于量子衍生涡流算法和T⁃S模糊推理模型的储层岩性识别
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作者 赵娅 管玉 +1 位作者 李盼池 王伟 《石油地球物理勘探》 EI CSCD 北大核心 2024年第1期23-30,共8页
鉴于梯度下降法易陷入局部极值、普通群智能优化算法易早熟收敛,提出一种基于量子衍生涡流算法(Quantum Vortex Search Algorithm,QVSA)和T⁃S模糊推理模型的岩性识别方法,QVSA具有操作简单、收敛速度快、寻优能力强等优点,有助于T⁃S模... 鉴于梯度下降法易陷入局部极值、普通群智能优化算法易早熟收敛,提出一种基于量子衍生涡流算法(Quantum Vortex Search Algorithm,QVSA)和T⁃S模糊推理模型的岩性识别方法,QVSA具有操作简单、收敛速度快、寻优能力强等优点,有助于T⁃S模糊推理模型获得最优参数配置,从而实现储层岩性的准确识别。首先利用具有全局搜索能力的QVSA优化T⁃S模糊推理模型的各种参数;然后利用主成分分析方法降低获取的地震属性维度;再利用优化的T⁃S模糊推理模型识别储层岩性。实验结果表明,利用反映储层特征的8个地震属性识别储层岩性时,所提方法的识别正确率达到92%,比普通BP网络方法高5.1%,同时查准率、查全率、F1分数等指标也较BP网络方法提升明显。 展开更多
关键词 储层岩性识别 量子衍生涡流算法 T⁃s 模糊推理模型 模糊集 地震属性
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基于XGBoost算法的v_(P)/v_(S)预测及其在储层检测中的应用
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作者 田仁飞 李山 +1 位作者 刘涛 景洋 《石油地球物理勘探》 EI CSCD 北大核心 2024年第4期653-663,共11页
鄂尔多斯盆地碳酸盐岩地层蕴含着丰富的油气资源。在勘探实践中发现,大牛地气田马家沟组断层发育、断距小,类型多样且成因复杂,给勘探、开发带来了较多挑战。为了应对这些挑战,提高储层预测的精度变得至关重要。在分析大牛地气田敏感弹... 鄂尔多斯盆地碳酸盐岩地层蕴含着丰富的油气资源。在勘探实践中发现,大牛地气田马家沟组断层发育、断距小,类型多样且成因复杂,给勘探、开发带来了较多挑战。为了应对这些挑战,提高储层预测的精度变得至关重要。在分析大牛地气田敏感弹性参数的基础上,建立地震属性与储层纵横波速度比(v_(P)/v_(S))的关系,提出一种基于XGBoost算法的地震多属性v_(P)/v_(S)预测方法。为了进一步提升XGBoost算法的预测精度和泛化能力,采用贝叶斯算法对XGBoost算法的超参数进行优化,从而找到最佳的超参数组合,以确保模型在训练集和测试集上的性能均能得到提升。将XGBoost算法应用于Marmousi 2模型进行横波速度预测,预测值与实际值相关系数超过0.88,而均方误差、平均绝对百分比误差分别低于6.55×10^(-7)和4%,验证了该方法的准确性和可靠性。在鄂尔多斯盆地大牛地气田,应用该方法获得的v_(P)/v_(S)成功识别出含气储层,结果与实际钻井数据一致。理论模型和实际数据应用结果表明,XGBoost作为一种强大的机器学习算法预测精度较高,为直接由叠后地震属性预测v_(P)/v_(S)提供了一种有效的途径。 展开更多
关键词 横波速度 碳酸盐岩储层 地震属性 XGBoost算法 纵横波速度比(v_(P)/v_(s))
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Effect of different inter-satellite range on measurement precision of Earth’s gravitational field from GRACE 被引量:3
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作者 Zheng Wei Hsu Houtse +2 位作者 Zhong Min Yun Meijuan Zhou Xuhua 《Geodesy and Geodynamics》 2012年第1期44-51,共8页
The precision of Earth's gravitational field from GRACE up to degree and order 120 was studied for different inter-satellite ranges using the improved energy conservation principle. Our simulated result shows that: ... The precision of Earth's gravitational field from GRACE up to degree and order 120 was studied for different inter-satellite ranges using the improved energy conservation principle. Our simulated result shows that: For long wavelength (L≤20) at degree 20, the cumulative geoid-height error gradually decreased with increasing range, from 0. 052 cm for 110 km to 1. 156 times and 1. 209 times as large for 220 km and 330 kin, respectively. For medium-wavelength ( 100 ≤ L ≤ 120) at degree 120, the cumulative geoid-height error de- creased from 13. 052 cm for 110 km, to 1. 327 times and 1. 970 times as large for the ranges of 220 km and 330 km, respectively; By adopting an optimal range of 220 ± 50 km, we can suppress considerably the loss of precision in the measurement of the Earth' s long-wavelength and medium-wavelength gravitational field. 展开更多
关键词 GRACE inter-satellite range colored noise Earth' s gravitational field energy conservation principle
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Range anomaly suppression based on neighborhood pixels detection in ladar range images 被引量:2
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作者 Mingbo Zhao Jun He +1 位作者 Zaiqi Lu Qiang Fu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2013年第1期68-75,共8页
Research on the range anomaly suppression algorithm in laser radar (ladar) range images is significant in the application and development of ladar. But most of existing algorithms cannot protect the edge and linear ... Research on the range anomaly suppression algorithm in laser radar (ladar) range images is significant in the application and development of ladar. But most of existing algorithms cannot protect the edge and linear target well while suppressing the range anomaly. Aiming at this problem, the differences among the edge, linear target, and range anomaly are analyzed and a novel algo- rithm based on neighborhood pixels detection is proposed. Firstly, the range differences between current pixel and its neighborhood pixels are calculated. Then, the number of neighborhood pixels is detected by the range difference threshold. Finally, whether the current pixel is a range anomaly is distinguished by the neighbor- hood pixel number threshold. Experimental results show that the new algorithm not only has a better range anomaly suppression performance and higher efficiency, but also protects the edge and linear target preferably compared with other algorithms. 展开更多
关键词 image processing range anomaly suppression neigh-borhood p xe s detection linear target laser radar (ladar).
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频率矫正广义S变换及在储层含油气性预测中的应用
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作者 刘乃豪 魏圣焘 +5 位作者 张泽洲 杨阳 王治国 刘镕菖 路漫 高静怀 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2024年第7期2820-2829,共10页
随着我国油气勘探程度的不断加深,陆相页岩油气等非常规油气逐渐成为我国勘探开发的重点,陆相页岩非均质性强、储层薄且纵横向变化剧烈等典型特征导致含油气性预测精度差,影响后续井位部署和生产等.时频变换方法是储层含油气性预测最有... 随着我国油气勘探程度的不断加深,陆相页岩油气等非常规油气逐渐成为我国勘探开发的重点,陆相页岩非均质性强、储层薄且纵横向变化剧烈等典型特征导致含油气性预测精度差,影响后续井位部署和生产等.时频变换方法是储层含油气性预测最有效的工具.为了提高储层含油气性预测的精度,本文提出了一种频率矫正广义S变换(Frequency-Corrected Generalized S-Transform, FCGST),该变换既具有S变换多尺度多分辨率的特性,又可以通过自适应选取窗函数参数以控制窗函数的带宽和主频等,这一特性可以适用于不同工区地震数据的处理与解释.与传统的S变换和广义S变换不同,该变换修正了传统S变换和广义S变换中的尺度因子,改善了S变换和广义S变换等传统方法中时频谱主频向高频方向偏移的问题,有利于精确描述复杂储层含油气性.合成数据算例表明,频率矫正广义S变换提升了地震信号局部时频特征的表征能力;将频率矫正广义S变换应用于鄂尔多斯盆地某工区储层含油气性预测中,实钻结果数据进一步验证了该时频分析方法在储层含油气性解释中的有效性和潜力. 展开更多
关键词 时频分析 广义s变换 频率矫正广义s变换 储层含油气性预测
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简易烈度计记录的噪声水平评价:以泸定M_(S)6.8级地震为例
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作者 郭文轩 任叶飞 +4 位作者 姚鑫鑫 岸田忠大 江鹏 王宏伟 温瑞智 《振动与冲击》 EI CSCD 北大核心 2024年第18期313-320,共8页
在我国地震预警和烈度速报系统中,烈度计被广泛使用。烈度计的频谱特征主要是通过检定实验室进行标定,但在破坏性地震中,烈度计响应特点缺少必要的研究分析。该文以2022年四川泸定M_(S)6.8级地震为例,对比分析了烈度计记录和强震仪记录... 在我国地震预警和烈度速报系统中,烈度计被广泛使用。烈度计的频谱特征主要是通过检定实验室进行标定,但在破坏性地震中,烈度计响应特点缺少必要的研究分析。该文以2022年四川泸定M_(S)6.8级地震为例,对比分析了烈度计记录和强震仪记录在噪声水平、信噪比(signal-to-noise ratio,SNR)、高通滤波截止频率(f_(HP))取值以及有效周期范围(T_(max))方面的特点,综合评价了烈度计记录的频谱特征,分析了噪声影响。得到以下结论:在整个频域范围内,烈度计记录的SNR要比强震仪记录平均意义上低一个数量级,可以估计烈度计动态范围较强震仪大致低20 dB;烈度计记录的最佳f_(HP)取值相较于强震仪记录存在更大的不确定性,尤其是在竖直方向上;烈度计记录的最佳f_(HP)取值更大,反应谱T_(max)较传统强震仪记录在水平方向小1~2 s,在竖直方向小3 s左右。该研究结果有助于合理应用烈度计记录,服务地震学和地震工程学相关研究。 展开更多
关键词 烈度计记录 信噪比(sNR) 高通滤波截止频率 有效周期范围 泸定6.8级地震
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Application of “Swanson’s Middle Range Caring Theory” in Sweden after miscarriage 被引量:2
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作者 Caroline Jansson Annsofie Adolfsson 《International Journal of Clinical Medicine》 2011年第2期102-109,共8页
Objective: The aim of this study was to apply Swanson’s Middle Range Caring Theory to the follow-up visit with a midwife for Swedish women who have suffered early miscarriage or received care for late missed miscarri... Objective: The aim of this study was to apply Swanson’s Middle Range Caring Theory to the follow-up visit with a midwife for Swedish women who have suffered early miscarriage or received care for late missed miscarriage in preg-nancy week 18-20. Methods: Twenty-five tape recorded interviews with women four weeks after their early miscarriages and thirteen tape recorded semi-structured interviews with midwives and nurses who had the experience of caring for women who have been diagnosed with a missed miscarriage during a routine ultrasound scan. The interviews were transcribed verbatim and interpreted deductively from the text using the theory. Results: Each woman described her personal experience of miscarriage in the relative terms of a human experience. The midwives and nurses described their experiences with women who received care for missed miscarriage. The interviews included information about the treatment provided by the caregivers during the period afterward of the diagnosis. The caregiver attitude was formed from Swanson’s caring categories: “Maintaining belief”, “knowing”, “being with”, “doing for”, “enabling”. Conclusions: Swanson’s Middle Range Caring Theory as applied to the caregiver includes being emotionally present, giving support with respect for the woman’s dignity, being competent, meeting each woman’s own individual needs. Given the proper care after a miscarriage every woman has the power within herself to improve their wellbeing. 展开更多
关键词 swanson’s MIDDLE range CARING THEORY MIsCARRIAGE MIssED MIsCARRIAGE Qualitative Method
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基于BIM+B/S的水库工程数字化展示平台的构建
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作者 杨玲 李靖 +1 位作者 王飞 樊兴东 《水利信息化》 2024年第2期69-73,共5页
针对水库工程在初步设计阶段仍以二维图纸作为成果交付,缺少对工程整体情况、投资估算等关键信息直观展示的问题,将BIM数字信息建模、BIM数据文件优化处理、B/S前后端分离、跨平台访问等技术应用于新建岔河水库工程,建立岔河水库枢纽BI... 针对水库工程在初步设计阶段仍以二维图纸作为成果交付,缺少对工程整体情况、投资估算等关键信息直观展示的问题,将BIM数字信息建模、BIM数据文件优化处理、B/S前后端分离、跨平台访问等技术应用于新建岔河水库工程,建立岔河水库枢纽BIM模型,创建实现平台功能的数据文件并构建岔河水库枢纽工程数字化展示平台。研究结果表明:构建的岔河水库工程数字化展示平台可以高效、流畅、跨平台地在电脑端和手机端,向参建各方展示待建枢纽工程的基本情况和地理位置,建筑物三维信息模型,单体工程的施工模拟动画,以及枢纽工程投资估算关键信息。研究结果深化BIM技术应用程度,可为其他水利工程信息化提供重要参考和借鉴价值。 展开更多
关键词 BIM B/s 数字化展示平台 水库工程
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Long-term hydrochemical monitoring and geothermometry:understanding groundwater salinization and thermal fluid contamination in Mila’s basin,Northeastern Algeria
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作者 Yasmina Bouroubi-Ouadfel Adnane Souffi Moulla Abdelkader Khiari 《Acta Geochimica》 EI CAS CSCD 2024年第3期459-477,共19页
The regular hydrochemical monitoring of groundwater in the Mila basin over an extended period has provided valuable insights into the origin of dissolved salts and the hydrogeochemical processes controlling water sali... The regular hydrochemical monitoring of groundwater in the Mila basin over an extended period has provided valuable insights into the origin of dissolved salts and the hydrogeochemical processes controlling water salinization.The data reveals that the shallow Karst aquifer shows an increase in TDS of 162 mg L^(-1) while the ther-mal carbonate aquifer that is also used for drinking water supply exhibits an increase of 178 mg L^(-1).Additionally,significant temperature variations are recorded at the sur-face in the shallow aquifers and the waters are carbo-gaseous.Analysis of dissolved major and minor elements has identified several processes influencing the chemical composition namely:dissolution of evaporitic minerals,reduction of sulphates,congruent and incongruent car-bonates’dissolution,dedolomitization and silicates’weathering.The hydrogeochemical and geothermometric results show a mixing of saline thermal water with recharge water of meteoric origin.Two main geothermalfields have been identified,a partially evolved water reservoir and a water reservoir whosefluid interacts with sulphuric acid(H_(2)S)of magmatic origin.These hot waters that are char-acterized by a strong hydrothermal alteration do ascend through faults and fractures and contribute to the contamination of shallower aquifers.Understanding the geothermometry and the hydrogeochemistry of waters is crucial for managing and protecting the quality of groundwater resources in the Mila basin,in order to ensure sustainable water supply for the region.A conceptual model for groundwater circulation and mineralization acquisition has been established to further enhance under-standing in this regard. 展开更多
关键词 Hydrochemical monitoring HYDROGEOCHEMIsTRY sALINIZATION Geothermal reservoir CONTAMINATION Mila’s basin
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Spatiotemporal Distributions of Bacterioplankton Communities in the Qiantang River(Hangzhou Section),China
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作者 XU Jiaojiao ZHAO Li +4 位作者 LUKWAMBE Betina NICHOLAUS Regan ZHU Jinyong YANG Wen ZHENG Zhongming 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第4期1102-1114,共13页
The spatial and temporal distribution of bacterioplankton communities plays a vital role in understanding the ecological dynamics and health of aquatic ecosystems.In this study,we conducted a comprehensive investigati... The spatial and temporal distribution of bacterioplankton communities plays a vital role in understanding the ecological dynamics and health of aquatic ecosystems.In this study,we conducted a comprehensive investigation of the bacterioplankton communities in the Qiantang River(Hangzhou section).Water samples were collected quarterly from seven sites over a one-year period.Physical and chemical parameters,including dissolved oxygen(DO),water temperature(WT),chemical oxygen demand(COD),nitrite(NO_(2)^(-)),active phosphate(PO_(4)^(3-))and other indices were determined.In this study,theαdiversity,βdiversity and abundance differences of bacterial communities were investigated using 16S rRNA high-throughput sequencing analysis.The spatial and temporal distribution characteristics and main driving factors of the bacterioplankton community structure and diversity were discussed.The results showed that a total of 57 phyla were detected in the bacterioplankton community,among which Proteobacteria and Actinomycetes were the two dominant groups with the highest relative abundance.The results of PCoA based on Bray-Curtis distance showed that the sampling season had a slightly greater effect on the changes in bacterioplankton community structure in the Qiantang River.Mantel and partial Mantel test showed that environmental variables(Mantel r=0.6739,P<0.0001;partial Mantel r=0.507,P=0.0001)were more important than geographical distance(Mantel r=0.5322,P<0.001;partial Mantel r=0.1563,P=0.001).The distance attenuation model showed that there was significant distance attenuation in all four seasons,and the maximum limit of bacterial community diffusion was found in spring.RDA analysis showed that nine environmental factors,including COD,WT and DO,significantly affected community distribution(P<0.05).This study provides valuable insights into the spatial and temporal distribution characteristics of bacterioplankton communities,shedding light on their ecological roles in the Qiantang River.The information obtained can guide future research on the interactions between bacterioplankton and their environment,enabling the development of effective conservation strategies and sustainable management practices for aquatic ecosystems. 展开更多
关键词 Qiantang River bacterioplankton community spatial and temporal distribution 16s rRNA range attenuation
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Origin and evolution of ore-forming fluid for the Gaosongshan gold deposit, Lesser Xing’an Range:Evidence from fluid inclusions,H-O-S-Pb isotopes 被引量:3
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作者 Yang Liu Jinggui Sun +4 位作者 Jilong Han Liang Ren Alei Gu Keqiang Zhao Changshen Wang 《Geoscience Frontiers》 SCIE CAS CSCD 2019年第5期1961-1980,共20页
Epithermal gold deposits are typical precious metal deposits related to volcanic and subvolcanic magmatism.Due to the lack of direct geological and petrographic evidences,the origin of the ore-forming fluid is deduced... Epithermal gold deposits are typical precious metal deposits related to volcanic and subvolcanic magmatism.Due to the lack of direct geological and petrographic evidences,the origin of the ore-forming fluid is deduced from the spatial diagenesis-mineralization relationship,chronological data,physicochemical characteristics of mineral fluid inclusions,mineral or rock elements and isotopic geochemical characteristics.By objectively examining this scientific problem via a geological field survey and petrographic analysis of the Gaosongshan epithermal gold deposit,we recently discovered and verified the following points:(1) Pyrite-bearing spherical quartz aggregates (PSQA) occur in the rhyolitic porphyry;(2) the mineralization is structurally dominated by WNW- and ENE-trending systems and occurs mostly in hydrothermal breccias and pyrite-quartz veins,and the ore types are mainly hematite-crusted quartz,hydrothermal breccia,massive pyrite-quartz,etc.;(3) the alteration types consist of prevalent silicification,sericitization,propylitization and carbonation,with local adularization and illitization.The ore minerals are mainly pyrite,primary hematite,native gold,and electrum,with lesser amounts of chalcopyrite,magnetite,sphalerite,and galena,indicating a characteristic epithermal low-sulfidation deposit.The ore-forming fluid may have been primarily derived from magmatic fluid exsolved from a crystallizing rhyolitic porphyry magma.Further zircon U-Pb geochronology,fluid inclusion,physicochemical and isotopic geochemical analyses revealed that (1) rhyolitic porphyry magmatism occurred at 104.6 ± 1.0 Ma,whereas the crystallization of the PSQA occurred at 100.8 ± 2.1 Ma;(2) the hydrothermal fluid of the pre-ore stage was an exsolved CO2-bearing H2O-NaCl magmatic fluid that produced inclusions mainly composed of pure vapor (PV),vapor-rich (WV) and liquid-rich (WL) inclusions with a small number of melt-(M) and solid-bearing (S) inclusions;mineralization-stage quartz contains WL and rare PV,WV and pure liquid (PL) inclusions characterized by the H2O-NaCl system with low formation temperatures and low salinities;(3) the characteristics of hydrogen,oxygen,sulfur,and lead isotopes and those of rare earth elements (REEs) provide insight into the affinity between PSQA and orebodies resulting from juvenile crust or enriched mantle.Combined with previous research on the mineralogenetic epoch (99.32 ± 0.01 Ma),we further confirm that the mineralization of the deposit occurred in the late Early Cretaceous,which coincides with the extension of the continental margin induced by subduction of the Pacific Plate beneath the Eurasian Plate.The formation of the ore deposit was proceeded by a series of magmatic and hydrothermal events,including melting of enriched juvenile crust,upwelling,the eruption and emplacement of the rhyolitic magma,the exsolution and accumulation of magmatic hydrothermal fluid,decompression,the cooling and immiscibility/boiling of the fluid,and mixing of the magmatic fluid with meteoric water,in association with water-rock interaction. 展开更多
关键词 Fluid inclusions H-O-s-Pb isotopes Zircon U-Pb dating Gaosongshan gold deposit Lesser Xing'an range Northeast China
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Closed Range Composition Operators on a General Family of Function Spaces
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作者 M.A.Bakhit 《Analysis in Theory and Applications》 CSCD 2016年第3期215-231,共17页
In this paper, necessary and sufficient conditions for a closed range composition operator CФ on the general family of holomorphic function spaces F(p,q,s) and more generally on α-Besov type spaces F(p,αp-2,s) ... In this paper, necessary and sufficient conditions for a closed range composition operator CФ on the general family of holomorphic function spaces F(p,q,s) and more generally on α-Besov type spaces F(p,αp-2,s) are given. We give a Carleson measure characterization on F (p, αp - 2, s) spaces, then we indicate how Carleson measures can be used to characterize boundedness and compactness of CФ on F(p,q,s) and F(p,αp- 2,s) spaces. 展开更多
关键词 Composition operators F(p q s spaces closed range Carleson measure Bloch space Bergman type space
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Multi-target ranging using an optical reservoir computing approach in the laterally coupled semiconductor lasers with self-feedback
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作者 Dong-Zhou Zhong Zhe Xu +5 位作者 Ya-Lan Hu Ke-Ke Zhao Jin-Bo Zhang Peng Hou Wan-An Deng Jiang-Tao Xi 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第7期309-320,共12页
We utilize three parallel reservoir computers using semiconductor lasers with optical feedback and light injection to model radar probe signals with delays.Three radar probe signals are generated by driving lasers con... We utilize three parallel reservoir computers using semiconductor lasers with optical feedback and light injection to model radar probe signals with delays.Three radar probe signals are generated by driving lasers constructed by a threeelement laser array with self-feedback.The response lasers are implemented also by a three-element lase array with both delay-time feedback and optical injection,which are utilized as nonlinear nodes to realize the reservoirs.We show that each delayed radar probe signal can be predicted well and to synchronize with its corresponding trained reservoir,even when parameter mismatches exist between the response laser array and the driving laser array.Based on this,the three synchronous probe signals are utilized for ranging to three targets,respectively,using Hilbert transform.It is demonstrated that the relative errors for ranging can be very small and less than 0.6%.Our findings show that optical reservoir computing provides an effective way for applications of target ranging. 展开更多
关键词 coupled semiconductor lasers lidar ranging optical reservoir computing chaos synchronization
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Curvature range measurements of the arcuate fasciculus using diffusion tensor tractography
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作者 Dong Hoon Lee Cheol Pyo Hong +3 位作者 Yong Hyun Kwon Yoon Tae Hwang Joong Hwi Kim Ji Won Park 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第3期244-250,共7页
Because Broca's area and Wernicke's area in the brain are connected by the arcuate fasciculus, understanding the anatomical location and morphometry of the arcuate fasciculus can help in the treatment of patients wi... Because Broca's area and Wernicke's area in the brain are connected by the arcuate fasciculus, understanding the anatomical location and morphometry of the arcuate fasciculus can help in the treatment of patients with aphasia. We measured the horizontal and vertical curvature ranges of the arcuate fasciculus in both hemispheres in 12 healthy subjects using diffusion tensor tractography. In the right hemisphere, the direct curvature range and indirect curvature range values of the arcuate fasciculus horizontal part were 121.13 ± 5.89 and 25.99 ± 3.01 degrees, respectively, and in the left hemisphere, the values were 121.83 ± 5.33 and 27.40 ± 2.96 degrees, respectively. In the right hemisphere, the direct curvature range and indirect curvature range values of the arcuate fasciculus vertical part were 43.97 ± 7.98 and 30.15 ± 3.82 degrees, respectively, and in the left hemisphere, the values were 39.39 ± 4.42 and 24.08 ± 4.34 degrees, respectively. We believe that the measured curvature ranges are important data for localization and quantitative assessment of specific neuronal pathways in patients presenting with arcuate fasciculus abnormalities. 展开更多
关键词 neural regeneration neuroimaging clinical practice diffusion tensor tractography diffusion tensor imaging arcuate fasciculus direct curvature range indirect curvature range anatomical location quantitative information APHAsIA Broca’s area Wernicke’s area arched fiber grant-supported paper photographs-containing paper NEUROREGENERATION
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小兴安岭东南部伊东林场金矿床成因探讨:来自流体包裹体和H-O-S-Pb同位素的证据
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作者 赵忠海 程斌彬 +4 位作者 尹业长 梁杉杉 乔锴 崔晓梦 李成禄 《大地构造与成矿学》 EI CAS CSCD 北大核心 2024年第5期1000-1016,共17页
伊东林场金矿是近年来在小兴安岭-张广才岭多金属成矿带内新发现的金矿,由于研究程度较低,尚未开展系统的矿床学研究。为限定伊东林场金矿成矿物质及流体来源、矿床成因类型等关键问题,本文开展了详细的野外地质调查、岩相学和矿相学观... 伊东林场金矿是近年来在小兴安岭-张广才岭多金属成矿带内新发现的金矿,由于研究程度较低,尚未开展系统的矿床学研究。为限定伊东林场金矿成矿物质及流体来源、矿床成因类型等关键问题,本文开展了详细的野外地质调查、岩相学和矿相学观察、流体包裹体及H-O-S-Pb同位素等分析。伊东林场金矿矿石矿物主要包括黄铁矿、黄铜矿、闪锌矿、辉银矿、方铅矿等。围岩蚀变类型主要包括硅化、黄铁矿化、绢云母化、碳酸盐化,黏土化,绿泥石化和冰长石化,其中硅化和碳酸盐化与金矿化关系最为密切。成矿过程可划分为石英-方解石-少量黄铁矿阶段(Ⅰ)、石英-方解石-多金属硫化物阶段(Ⅱ)和少量硫化物-碳酸盐阶段(Ⅲ)。流体包裹体以气液两相为主,从成矿早期到晚期各阶段平均成矿温度为311℃→260℃→200℃,逐渐降低;盐度为0.2%~4.5%NaCl_(eq),密度为0.56~0.93 g/cm^(3),为中低温、低盐度、低密度的H_(2)O-NaCl体系,成矿深度小于1 km,形成于浅成环境。H-O同位素组成显示,成矿流体主要为岩浆水与大气降水混合,以大气降水为主,并与围岩发生了明显的水-岩反应;S-Pb同位素组成表明成矿物质主要来源于赋矿火山-次火山岩。通过与区内典型的中生代低硫化型浅成低温热液型金矿床特征进行对比,结合矿床地质特征、成矿流体以及稳定同位素特征,认为伊东林场金矿床为典型的低硫化型浅成低温热液型金矿床。 展开更多
关键词 流体包裹体 H-O-s-Pb同位素 矿床成因 伊东林场金矿 小兴安岭
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鄂北S井区盒8上亚段砂体叠置类型及其对气藏分布的影响
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作者 杜家满 赵永刚 +2 位作者 申荣荣 于明航 阴旭航 《录井工程》 2024年第1期119-126,共8页
为明确鄂北S井区盒8上亚段地层砂体叠置类型及其与气藏分布的关系,通过岩心观察、测井解释等方法对研究区盒8上亚段沉积微相类型、砂体的垂向叠置及侧向接触关系进行深入研究,再结合试气资料探讨不同砂体叠置类型的气藏分布特征。结果表... 为明确鄂北S井区盒8上亚段地层砂体叠置类型及其与气藏分布的关系,通过岩心观察、测井解释等方法对研究区盒8上亚段沉积微相类型、砂体的垂向叠置及侧向接触关系进行深入研究,再结合试气资料探讨不同砂体叠置类型的气藏分布特征。结果表明:鄂北S井区盒8上亚段为曲流河三角洲平原亚相,有利砂体对应的沉积微相类型为边滩与河道充填微相;砂体垂向叠置类型可划分为分离式、叠加式、切叠式、替代式,侧向接触关系可划分为间湾接触、堤岸接触、对接式、侧切式、替代式;鄂北S井区盒8上亚段砂体垂向叠置类型主要为侧向切叠式和替代式,增加了砂体在侧向上的连通性;盒8上亚段砂体侧向接触关系主要为侧切式,提升了砂体侧向上的连通程度,气藏储存关系较好;单一、孤立存在的砂体,其连通性较差,整体的含气性也较差。该研究对寻找低渗透背景下产能高、潜力大的砂体分布区具有重要指导意义。 展开更多
关键词 鄂北s井区 盒8上亚段 砂体垂向叠置 砂体侧向接触 气藏分布
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