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Geochemistry of the Late Paleozoic cherts in the Youjiang Basin:Implications for the basin evolution

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Journal of Palaeogeography 2013年第4期2卷 402-421页

作者： Huang Hu du Yuansheng Yang jianghai Huang Hongwei Tao Ping Huang Zhiqiang Yu Wenchao Guo Hua State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences (Wuhan) General Academy of Geological Survey of Guangxi Guizhou Academy of Geological Survey

We analyzed the major and rare earth element compositions of siliceous deposits from the Upper Devonian Liujiang Formation,Lower Carboniferous Luzhai Formation,Lower-Middle Permian Sidazhai Formation and Tapi Formation,which are widely distributed as bedded cherts in the interplatform basinal successions of the Youjiang *** Liujiang Formation and Luzhai Formation cherts generally have high Al/(Al+Fe+Mn) values(0.38-0.94) and are non-hydrothermal *** cherts are generally characterized by moderately negative Ce anomalies and high Y/Ho values relatived to PAAS,indicating that the Youjiang Basin might have evolved into an open rift basin during the Late Devonian-Early *** Sidazhai Formation cherts from Ziyun generally have high Al/(Al+Fe+Mn) values(0.60-0.78),suggesting negligible contribution from a hydrothermal *** Sidazhai Formation cherts from Hechi and the Tapi Formation cherts from Malipo generally have low Al/(Al+Fe+Mn) values(0.09-0.41),indicating an intense hydrothermal *** to the Sidazhai Formation cherts,the Tapi Formation cherts have higher Ce/Ce*values(0.68±0.19) and lower Y/Ho values(41.83±13.27),which may be affected by the terrigenous input from the Vietnam *** Sidazhai Formation cherts from Ziyun and Hechi exhibit negative Ce anomalies(0.43±0.12,0.33±0.17,respectively) with high Y/Ho values(57.44±16.20,46.02±4.27,respectively),resembling the geochemical characteristics of open-ocean basin *** cherts were deposited on a passive continental margin adjacent to the Babu branch ocean,which may have contributed to *** spatial studies on geochemical characteristics of the Late Paleozoic cherts can unravel the evolution of the Youjiang Basin.

关键词： Late Paleozoic chert Liujiang Formation Luzhai Formation Sidazhai Formation Tapi Formation basin evolution Youjiang Basin Yangtze Block Vietnam Block

Interlinking the Hotspot Track in the Arctic and its Implications for Paleo-plate Reconstrution

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Acta Geologica Sinica(English Edition) 2017年第3期91卷 822-831页

作者： LIU Zhonglan LI jianghai LIU Chiheng LI Weibo ZHANG Hongwei The Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of EducationSchool of Earth and Space SciencesPeking University Lamont Doherty Earth Observatory Columbia University Institute of Oil & Gas Peking University

The Siberian-Icelandic hotspot track is the only preserved continental hotspot track. Although the track and its associated age progression between 160 Ma and 60 Ma are not yet well understood, this section of the track is closely linked to the tectonic evolution of Amerasian Basin, the Alpha-Mendeleev Ridge and Baffin Bay. Using paleomagnetic data, volcanic structures and marine geophysical data, the paleogeography of Arctic plates （Eurasian plate, North American Plate, Greenland Plate and Alaska Microplate） was reconstructed and the Siberian-Icelandic hotspot track was interlinked between 160 Ma and 60 Ma. Our results suggested that the Alpha-Mendeleev Ridge could be a part of the hotspot track that formed between 160 Ma and 120 Ma. during this period, the hotspot controlled the tectonic evolution of Baffin Bay and the distribution of mafic rock in Greenland. Throughout the Mesozoic Era, the aforementioned Arctic plates experienced clockwise rotation and migrated northeast towards the North Pacific. The vertical influence from the ancient Icelandic mantle plume broke this balance, slowing down some plates and resulting in the opening of several ocean basins. This process controlled the tectonic evolution of the Arctic.

关键词： hotspot track large igneous province paleogeography reconstruction Alpha-Mendeleevridge the Arctic

Conodont Biostratigraphic Constraint on the Lower Taiyuan Formation in Southern North China and Its Paleogeographic Implications

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Journal of Earth Science 2022年第6期33卷 1480-1493页

作者： Yuan Wang jianghai Yang Dong-Xun Yuan Jia Liu Rui Ma School of Earth Sciences China University of GeosciencesWuhan430074China State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan430074China School of Resources and Geosciences China University of Mining and TechnologyXuzhou221116China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and PaleoenvironmentChinese Academy of SciencesNanjing210008China

The Late Paleozoic Taiyuan Formation in North China is mainly composed of a mixed shallow-marine carbonate and terrigenous clastic *** basal limestones have been constrained in the late Pennsylvanian to Early *** further constrain the age of the lowest Taiyuan Formation,we obtained two genera and 16 species of conodonts from the bottom limestones of the Taiyuan Formation in two sections in Henan Province,southern North *** fauna includes Idiognathodus hebeiensis,Streptognathodus isolatus,***,***,***,***,***,***,***,***,***,***,***,***,***,and ***.A genus of Streptognathodus dominated conodont assemblage with some Idiognathodus *** indicates a late Gzhelian(latest Pennsylvanian)age for the lowest Taiyuan Formation in southern North *** is consistent with recently published high-precision zircon U-Pb ages from ash *** on conodont biostratigraphy,the basal limestones of the Taiyuan Formation in Henan Province(southern North China)can be correlated with the upper part of Miaogou limestones of the Taiyuan Formation in Shanxi Province(northern North China).This correlation might reflect a significant sea-level rise in North China,possibly corresponding to a deglaciation event at the Permo-Carboniferous transition.

关键词： Taiyuan Formation conodonts Gzhelian southern North China biostratigraphy

Heat Shielding Effects in the Earth＇s Crust

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Journal of Earth Science 2017年第1期28卷 161-167页

作者： Yixian Xu Lupei Zhu Qinyan Wang Yinhe Luo jianghai Xia School of Earth Sciences Zhejiang University Hangzhou 310027 China State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan 430074 China Hubei Subsurface Multi-Scale lmaging Key Laboratory Institute of Geophysics and Geomatics China University of Geosciences Wuhan 430074 China Department of Earth and Atmospherie Sciences Saint Louis University St. Louis MO 63103 USA School of Earth Sciences China University of Geosciences Wuhan 430074 China

Knowledge of heat flow and associated variations of temperature with depth is crucial for understanding how the Earth functions. Here, we demonstrate possible heat shielding effects that result from the occurrence of mafic intrusions/layers（granulitic rocks） within a dominantly granitic middle crust and/or ultramafic intrusions/layers（peridotitic rocks） within a dominantly granulitic lower crust; heat shielding is a familiar phenomenon in heat engineering and thermal metamaterials. Simple one-dimensional calculations suggest that heat shielding due to the intercalation of granitic, granulitic and peridotitic rocks will increase Moho temperatures substantially. This study may lead to a rethinking of numerous proposed lower crustal processes.

关键词： geotherm crustal laminated structure heat shielding heat conductivity peridotitic in-trusions North Tibet magnetotelluric data.

Seismic Reflection Characteristics of Naturally-Induced Subsidence Affecting Transportation

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Journal of China University of Geosciences 2009年第3期20卷 496-512页

作者： Richard D Miller jianghai Xia Don W Steeples Kansas Geological Survey The University of Kansas Lawrence KS 66047 USA Department of Geology The University of Kansas Lawrence KS 66047 USA

High-resolution seismic reflections have been used effectively to investigate sinkholes formed from the dissolution of a bedded salt unit found throughout most of Central Kansas. Surface subsidence can have devastating effects on transportation structures. Roads, rails, bridges, and pipelines can even be dramatically affected by minor ground instability. Areas susceptible to surface subsidence can put public safety at risk. Subsurface expressions significantly larger than surface depressions are consistently observed on seismic images recorded over sinkholes in Kansas. Until subsidence reaches the ground surface, failure appears to be controlled by compressional forces evidenced by faults with reverse orientation. Once a surface depression forms or dissolution of the salt slows or stops, subsidence structures are consistent with a tensional stress environment with prevalent normal faults. Detecting areas of rapid subsidence potential, prior to surface failure, is the ultimate goal of any geotechnical survey where the ground surface is susceptible to settling. Seismic reflection images have helped correlate active subsidence to dormant paleofeatures, project horizontal growth of active sinkholes based on subsurface structures, and appraise the risk of catastrophic failure.

关键词： shallow seismic reflection imaging subsidence sinkhole.

基于模式识别技术的无线通信网络安全系统设计

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通信电源技术 2024年第12期41卷 43-45页

作者：吴江海桂孝美朱魏峰浙江省邮电工程建设有限公司浙江杭州310000

探索模式识别技术在无线网络安全领域的应用,设计一种多层次、模块化的网络安全系统。该系统通过数据采集、特征提取、模式识别与分析及安全策略优化等环节,实现无线网络安全态势的实时感知和动态防御。仿真实验结果表明,该系统能够有... 详细信息

探索模式识别技术在无线网络安全领域的应用,设计一种多层次、模块化的网络安全系统。该系统通过数据采集、特征提取、模式识别与分析及安全策略优化等环节,实现无线网络安全态势的实时感知和动态防御。仿真实验结果表明,该系统能够有效识别多种类型的网络攻击,具有较高的检测率、较低的误报率以及优秀的健壮性。

关键词：无线通信网络网络安全模式识别

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基于无线通信的智能制造仓储系统设计

通信电源技术 2024年第13期41卷 28-30页

作者：桂孝美张李景吴江海浙江省邮电工程建设有限公司浙江杭州310000

文章针对传统仓储系统存在的效率低和柔性差等问题,提出一种基于无线通信技术的智能制造仓储系统设计方案。该系统综合运用射频识别(Radio Frequency IDentification,RFID)、无线传感器网络(Wireless Sensor Networks,WSN)、5G等技术,... 详细信息

文章针对传统仓储系统存在的效率低和柔性差等问题,提出一种基于无线通信技术的智能制造仓储系统设计方案。该系统综合运用射频识别(Radio Frequency IDentification,RFID)、无线传感器网络(Wireless Sensor Networks,WSN)、5G等技术,并融合多智能体协同调度和知识图谱推理等人工智能算法,实现仓储作业的实时监控、动态优化以及智能决策。仿真实验结果表明,该系统在出入库效率、任务响应速度、异常处理能力等方面性能较好。

关键词：智能制造仓储系统无线通信

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伸缩式绳索落物打捞器的研制与应用

江汉石油职工大学学报 2024年第1期37卷 48-49,55页

作者：程汉生吴继农路江海程忠中石化江汉油田分公司采油气工程技术服务中心湖北潜江433123

针对油田修井作业中绳类工具打捞复杂、效率低的难题,通过分析影响绳索打捞工艺的主要因素并采取相应的对策,研制一种伸缩式绳索落物打捞器及操作方法,对简化施工工序、降低劳动强度、提高复杂绳类落物打捞效率是一次有益尝试。

关键词：绳索落物伸缩打捞机械震击

Radiolarian and Detrital Zircon in the Upper Carboniferous to Permian Bancheng Formation,Qinfang Basin,and the Geological Significance

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Journal of Earth Science 2018年第3期29卷 594-606页

作者： Xue Ke Zongyan Zhang jianghai Yang Huazhou Yao Likuan Zhu Weihong He Institute of Geological Survey China University of GeosciencesWuhan 430074China Wuhan Center of China Geological Survey Wuhan 430205China State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan 430074China School of Earth Sciences China University of GeosciencesWuhan 430074China Zhengzhou Institute of Multipurpose Utilization of Mineral Resources Chinese Academy of Geological SciencesZhengzhou 450006China

The Bancheng Formation exposed along the Shift Reservoir nearby Bancheng Town, Qinfang Basin, southern Guangxi, is mainly composed of thin-bedded chert. The radiolarian assemblages in the studied section suggest it was a pelagic setting and the age of the Bancheng Formation is Late Carboniferous to Early Permian. The detrital zircon U-Pb ages from the section are characterized by a Permian peak at -282 Ma. Detrital zircon provenance analysis suggests that the Permian detrital zircons in the Bancheng Formation were likely from volcanic-magmatic arc rocks related to the subducfton of the Paleo-Tethyan Ocean. The long-lived deposition （from Upper Devonian to Middle Permian, about 125 Ma） of the radiolarian cherts in the Qinfang Basin was comparable with that deposited in Ailaoshan Ocean. The radiolarian assemblages in Qinfang Basin show a Tethyan affinity. Together with the Permian subduction-related arc volcanic rocks and the E-MORB type basalts to the northwest of the study area, our data support the existence of a Permian arc-related basin in the Qinfang area.

关键词： Qinfang Basin Bancheng Formation detrital zircon radiolarian Permian arc-related basin.