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The growth of the screw dislocation of nacreous layer on Pteria penguin

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Science China Earth Sciences 2011年第7期54卷 951-958页

作者： QI LiJian HUANG YiLan zhou zuyi zhou ZhengYu State Key Laboratory of Marine Geology Tongji University Shanghai 200092 China Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China

In response to various environmental factors in offshore South China Sea,a group of microstructures of the screw dislocation are assembled in multiphase screw dislocations on the surface of the nacreous layer of Pteria penguin from the coastal waters of Hainan Island,*** results of the transmission and scanning electronic microscope testing show that organic matter periodically secreted by epithelial histology of mantle of Pteria penguin pre-forms the original screw dislocation growth tem-plate in the form of film,along with its function to select,identify,and adhere to the amorphous calcium carbonate particles as the fine organic venations diffused in the epitaxial screw growth *** the inducement and screw modulation of the or-ganic film and venations,the amorphous calcium carbonate particles gradually evolve into the pseudohexagonal *** microsheet with long-range order and screw dislocation structure by location-selecting tropism and screw dislocation *** micron-scale aragonite microsheets join in the cluster's interactive movement and screw dislocation self-assembly of the organic film,stacking forward along the axis C spirally and forming the nacreous layer with screw dislocation structure.

关键词： Pteria penguin nacreous layer organic film aragonite micro sheet screw dislocation

Zircon U-Pb Dating on Granitoids from the Northern South China Sea and its Geotectonic Relevance

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Acta Geologica Sinica(English Edition) 2011年第6期85卷 1359-1372页

作者： SHI Hesheng XU Changhai zhou zuyi MA Changqian tate Key Laboratory of Marine Geology longji University Shanghai 200092 China CNOOC China Limited-Shenzhen Shenzhen 518067 China State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan 430074 China

Zircon U-Pb ages of 163.8-100.4 Ma and 146.6-134.5 Ma are obtained for the granitoids from the Pearl River mouth basin, and from southern Guangdong Province, respectively. These new dating data accord well with the crystallization ages of Yanshanian granitoids broadly in the Nanling. The active continental margin of South China, as revealed by a combination of zircon U-Pb data, underwent a key granitoid-dominated magmatism in 165-100 Ma. Its evolution varied temporally, and spatially, registering under control of the paleo-Pacific slab subduction. The granitoids that occurred in 165-150 Ma broadly from the South China Sea to the Nanling are preferably related to two settings from volcanic-arc to back-arc extension, respectively. The activities of Cretaceous granitoids migrated from the southeastern Guangdong （148-130 Ma） to the Pearl River Mouth basin （127-112 Ma）, corresponding to the model of a retreating subduction. The subduction-related granitoid magmatism in South China continued until 108-97 Ma. A tectonic transformation from slab-subduction to extension should occur at -100 Ma.

关键词： granitoid zircon U-Pb dating active continental margin South China

Stress field modeling of northwestern South China Sea since 5.3 Ma and its tectonic significance

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Acta Oceanologica Sinica 2013年第12期32卷 31-39页

作者： YANG Fengli zhou zuyi ZHANG Na LIU Ning NI Bin School of Ocean and Earth Science Tongji University

Tectonically,the northwestern South China Sea(SCS)is located at the junction between three micro-plates,i.e.,the Indochina,South China and Zhongsha-Xisha micro-plates,and involves three basins,i.e.,the Yinggehai Basin,the Qiongdongnan Basin and Xisha Trough in the east,and the Zhongjiannan Basin in the *** the Pliocene(5.3 Ma),the Yinggehai Basin has experienced repeated accelerating subsidence,high thermal fluid,and widely developing mud-rich overpressure chambers,abundant mud diapers and crust-mantle mixed *** a large central canyon was developed in the Qiongdongnan Basin,new rift occurred in the Xisha *** characteristics demonstrate a single tectonic unit for the northwestern SCS,for which we have undertaken stress field modeling to understand its plate deformations and sedimentary *** results demonstrate that an extension tectonic event occurred after 5.3 Ma in the Yinggehai-Qiongdongnan-Xisha trough area,which is characterized by thinner crust(3 500 m).A new rift system subsequently was developed in this area;this event was mainly driven by the combined effects of different movement velocity and direction of the three micro-plates,and the far-field effect of the continental collision between the Indian Plate and the Tibetan Plateau,and subduction of the Pacific Plate underneath the Eurasian Plate.

关键词： northwestern South China Sea Pliocene stress field modeling rift system

基于多目标遗传算法的外骨骼人-机并联系统性能优化

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天津理工大学学报 2024年第5期40卷 86-93页

作者：齐文耀杨玉维周祖意天津理工大学天津市先进机电系统设计与智能控制重点实验室天津理工大学机电工程国家级实验教学示范中心

在提出一种具有仿生交变穿戴接触刚度的膝关节外骨骼人-机物理交互(穿戴)系统研究原型的基础上，开展穿戴系统参数优化分析，用于实现其穿戴舒适性与承载有效性的提高。首先，基于Ansys软件平台，搭建系统虚拟样机模型；其次，基于仿真... 详细信息

在提出一种具有仿生交变穿戴接触刚度的膝关节外骨骼人-机物理交互(穿戴)系统研究原型的基础上，开展穿戴系统参数优化分析，用于实现其穿戴舒适性与承载有效性的提高。首先，基于Ansys软件平台，搭建系统虚拟样机模型；其次，基于仿真分析，构造一种计及外骨骼缓冲层结构、材料参数为设计参变量的可穿戴性新型综合评价指标——穿戴舒适度，并获取后续优化初始数据种群；最后，针对穿戴舒适度指标开展多目标遗传优化分析，以寻找外骨骼穿戴系统的设计参数最优值。仿真分析表明，大腿肌群穿戴处最大等效应力(Von-Mises)有效值相对优化前降低44.45%,最大有效变形降低2.86%,有效受力结点数占比提高1.75%。因此，仿真结果可佐证上述人-机并联物理交互系统设计与其性能优化方法的有效性与合理性。

关键词：膝关节外骨骼机器人穿戴舒适度人-机并联多目标遗传算法

The Southward Extension of Cathaysia Block: Evidence from Zircon UPb Dates of Borehole Volcanics in the Northern South China Sea

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Acta Geologica Sinica(English Edition) 2013年第5期87卷 1370-1386页

作者： XU Changhai QUE Xiaoming SHI Hesheng zhou zuyi MA Changqian State Key Laboratory of Marine Geology Tongji University CNOOC China Limited-Shenzhen State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences

Five Paleogene volcanics sampled from the northern South China Sea were analyzed via LA-ICP-MS zircon U-Pb dating, including basalt and andesite from Borehole SCSVI and volcanic agglomerate from Borehole SCSV2, respectively. A total of 162 zircon U-Pb dates for them cover an age range from Neoarchean to Eocene, in which the pre-Paleocene data dominate. The Paleogene dates of 62.5±2.2 Ma and 42.1±2.9 Ma are associated with two igneous episodes prior to opening of South China Sea basin. Those pre-Paleocene zircons are inherited zircons mostly with magmatogenic oscillatory zones, and have REE features of crustal zircon. Zircon U-Pb dates of 2518-2481 Ma, 1933- 1724 Ma, and 1094-1040 Ma from the SCSV1 volcanics, and 2810-2718 Ma, 2458-2421 Ma, and 1850-993.4 Ma from the SCSV2 volcanics reveal part of Precambrian evolution of the northern South China Sea, well comparable with age records dated from the Cathaysia block. The data of 927.0±6.9 Ma and 781±38 Ma dated from the SCSV2 coincide with amalgamation between Yangtze and Cathaysia blocks and breakup of the Rodinia, respectively. The age records of Caledonian orogeny from the Cathaysia block are widely found from our volcanic samples with concordant mean ages of 432.0±5.8 Ma from the SCSV1 and of 437±15 Ma from the SCSV2. The part of the northern South China Sea resembling the Cathaysia underwent Indosinian and Yanshannian tectonothermal events. Their age signatures from the SCSV1 cover 266.5±3.5 Ma, 241.1±6.0 Ma, 184.0±4.2 Ma, 160.9±4.2 Ma and 102.8±2.6 Ma, and from the SCSV2 are 244±15 Ma, 158.1±3.5 Ma, 141±13 Ma and 96.3±2.1 Ma. Our pre-Paleogene U-Pb age spectra of zircons from the borehole volcanics indicate that the northern South China Sea underwent an evolution from formation of Precambrian basement, Caledonian orogeny, and Indosinian orogeny to Yanshannian magmatism. This process can be well comparable with the tectonic evolution of South China, largely supporting the areas of the northern South China Sea as p

关键词： Borehole volcanics zircon U-Pb dates northern South China Sea Cathaysia

Modelling of low-temperature exhumation rate in Dabie Mountain based on (U-Th)/He and fission-track thermochronological data

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Science China Earth Sciences 2006年第10期49卷 1009-1019页

作者： DING Ruxin zhou zuyi XU Changhai LIU Yuzhu CHENG Hao XU Fei State Key Laboratory of Marine Geology Tongji UniversityShanghai 200092China State Key Laboratory of Marine GeologyTongji UniversityShanghai 200092China State Key Laboratory of Marine GeologyTongji UniversityShanghai 200092China State Key Laboratory of Marine GeologyTongji UniversityShanghai 200092China State Key Laboratory of Marine GeologyTongji UniversityShanghai 200092China State Key Laboratory of Marine GeologyTongji UniversityShanghai 200092China

While the high-temperature exhumation process in the Dabie Mountain has been well documented, the low-temperature exhumation of this area since Cretaceous, especially since Late Cretaceous, is relatively less studied. Low-temperature thermochronology provides one of the important approaches to solve this problem. Based on the data of fission track and (U-Th)/He analysis of apaptites and zircons from the granitoid and metamorphic rocks in the Dabie Mountain, this paper applies Mancktelow’s and Braun’s methods to estimating the exhumation rates and to drawing the regional differential exhumation pattern since Cretaceous, especially since Late Cretaceous by taking into consideration factors such as heat transport, heat advection, topography and heat production, which could influence geothermal field in the shallow crust. Since Cretaceous, the exhumation rate (0.08-0.10 km/Ma) in the region around Tiantangzhai and in the south of Tanlu fault zone is larger than the rate (0.04-0.07 km/Ma) in other areas of the Dabie Mountain. The regional differential exhumation pattern might be related to the push-up effect caused by differential strike-slip movement along NNE-trending faults.

关键词： Dabie Mountain, fission track, (U-Th)/He, modelling, exhumation.

Precollisional tectonics and terrain amalgamation offshore southern Taiwan:Characterizations from reflection seismic and potential field data

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Science China Earth Sciences 2007年第6期50卷 897-908页

作者： LI ChunFeng zhou zuyi LI JiaBiao CHEN HuanJiang GENG JianHua LI Hui State Key Laboratory of Marine Geology Tongji UniversityShanghai 200092China The Second Institute of Oceanography State Oceanic AdministrationHangzhou 310012China

Sponsored by the Chinese National Fundamental Research and Development Program in 2001,Guang-zhou Marine Geological Survey launched out a long geophysical survey from the northeastern part of the South China Sea (SCS),through the Luzon Arc,to the Huatung Basin and the Gagua Ridge. Based on high-resolution seismic data from this survey,combined with gravimetric and magnetic modeling,a systematic effort is made to the study of the regional geodynamics offshore southern Taiwan. By focusing particularly on precollisional tectonic interactions between adjacent geological units and their tectonic affiliations,this study can help reveal early arc-continent collisional processes that formed the Taiwan orogen. The construction of the Manila accretionary prism and its eastward progressive deformation indicate that the subduction of SCS have experienced multiple phases of increased activity. Active precollisional crustal shortening within the Northern Luzon Trough resulted in tilting of sedimentary layers at angles between 6° and 13°. But the shortening induced by tilting accounts for only a tiny part of regional total crustal compression. The eastern flank of the Luzon Arc appears to be more active than the rest,evidenced by active faulting and folding in the intra-arc basins on the eastern flank. Magnetic modeling/inversion shows that the Luzon Arc may have experienced multiple phases of magmatic activities,causing lateral magnetic inhomogeneity. Bouguer gravity anomalies and gravity modeling indicate that the Huatung Basin has anomalously higher crustal and upper mantle densities than those of SCS and the Luzon Arc. In addition,there is a large bathymetric difference between the Huatung Basin and the northeastern part of SCS basin. These observations argue against early hypothesis that the Huatung Basin and the northeastern part of SCS basin may once have belonged to one single oceanic crust,in part or in whole. The Gagua Ridge,as a sliver of uplifted oceanic crust,may be r

关键词： precollisional tectonics Taiwan orogen Luzon Arc gravity and magnetic modeling Bouguer gravity anomaly Huatung Basin

Rapid exhumation of the Tianshan Mountains since the early Miocene:Evidence from combined apatite fission track and(U-Th)/He thermochronology

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Science China Earth Sciences 2013年第12期56卷 2116-2125页

作者： Lü HongHua CHANG Yuan WANG Wei zhou zuyi School of Resources and Environmental Science East China Normal University State Key Laboratory of Marine Geology Tongji University

Combined apatite fission track （AFT） and （U-Th）/He （AHe） thermochronometries can be of great value for investigating the history of exhumation of orogenic belts. We evaluate the results of such a combined approach through the study on rock sam- ples collected from the Baluntai section in the Tianshan Mountains, northwestern China. Our results show that AFT ages range from -60 to 40 Ma and Atte ages span -40-10 Ma. Based on the strict thermochronological constraints imposed by AHe ages, forward modeling of data derived from AFT analyses provides a well-constrained Cenozoic thermal history. The modeled re- sults reveal a history of relatively slow exhumation during the early Cenozoic times followed by a significantly accelerated exhumation process since the early Miocene with the rate increasing from 〈30 m/Myr to 〉 100 m/Myr, which is consistent with the inference from the exhumation rates calculated based on both AFT and AHe age data by age-closure temperature and mine- ral pair methods. Further accelerated exhumation since the late Miocene is recorded by an AHe age （-11 Ma） from the bottom of the Baluntai section. Together with the previous low-temperature thermochronological data from the other parts of the Tianshan Mountains, the rapid exhumation since the early Miocene is regarded as an important exhumation process likely pre- vailing within the whole range.

关键词： fission track (U-Th)/He exhumation Cenozoic the Tianshan Mountains

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Late Cretaceous-Cenozoic exhumation history of Tiantangzhai region of Dabieshan Orogen: Constraints from (U-Th)/He and fission track analysis

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Chinese Science Bulletin 2003年第11期48卷 1151-1164页

作者： zhou zuyi XU Changhai P. W. Reiners YANG Fengli R. A. Donelick MOE Laboratory of Marine Geology Tongji UniversityMOE Laboratory of Marine Geology Tongji UniversityDepartment of Geology and Geophysics Yale UniversityMOE Laboratory of Marine Geology Tongji UniversityDonelick Analytical Inc. Shanghai 200092 ChinaShanghai 200092 ChinaNew Haven CT 06520-8109 USAShanghai 200092 ChinaViola ID 83872 USA

Integrated fission track and (U-Th)/He analysis is carried out on 6 apatite and 6 zircon samples from a near vertical section in The Tiantangzhai region at the core of the present Dabieshan orogen. The result shows that the region experienced cooling/exhumation during the Late Cretaceous and Early Tertiary period. Age-elevation relationships for different dating systems and different minerals suggest a pulse of rapid exhumation at ～110 Ma before present, preserved in the structurally highest samples. At lower elevations, ages begin to decrease with decreasing elevation, suggesting lower exhumation rates since 90 Ma. Two periods of different exhumation rates are identified since 90 Ma. The average apparent exhumation rate for the period of 43.4-22.5 is 0.062 km/Ma, whereas that for the period of 76.4-47.4 Ma is 0.039 km/Ma.

关键词：大别山造山运动海拔高度第三纪白垩纪造山带