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P-T-t Path of Mafic Granulite Metamorphism in Northern Tibet and Its Geodynamical Implications

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Acta Geologica Sinica(English Edition) 2004年第1期78卷 155-165页

作者： HUDaogong WUZhenhan jiangwan YEPeisheng InstituteofGeomechanics ChineseAcademyofGeologicalSciencesBeijing100081

Mafic granulites have been found as structural lenses within the huge thrust system outcropping about 10 km west of Nam Co of the northern Lhasa Terrane, Tibetan Plateau. Petrological evidence from these rocks indicates four distinct metamorphic assemblages. The early metamorphic assemblage (M1) is preserved only in the granulites and represented by plagioclase+hornblende inclusions within the cores of garnet porphyroblasts. The peak assemblage (M2) consists of garnet+clinopyroxene+hornblende+plagioclase in the mafic granulites. The peak metamorphism was followed by near-isothermal decompression (M3), which resulted in the development of hornblende+plagioclase symplectites surrounding embayed garnet porphyroblasts, and decompression-cooling (M4) is represented by minerals of hornblende+plagioclase recrystallized during mylonization. The peak (M2) P-T conditions of garnet+ clinopyroxene+plagioclase+hornblende were estimated at 769-905℃ and 0.86-1.02 GPa based on the geothermometers and geobarometers. The P-T conditions of plagioclase+hornblende symplectites (M3) were estimated at 720-800℃ and 0.55-0.68 GPa, and recrystallized hornblende+plagioclase (M4) at 594-708℃ and 0.26-0.47 GPa. It is impossible to estimate the P-T conditions of the early metamorphic assemblage (M1) because of the absence of modal minerals. The combination of petrographic textures, metamorphic reaction history, thermobarometric data and corresponding isotopic ages defines a clockwise near-isothermal decompression metamorphic path, suggesting that the mafic granulites had undergone initial crustal thickening, subsequent exhumation, and cooling and retrogression. This tectonothermal path is considered to record two major phases of collision which resulted in both the assemblage of Gondwanaland during the Pan-African orogeny at 531 Ma and the collision of the Qiangtang and Lhasa Terranes at 174 Ma, respectively.

关键词： continental collision mafic granulite P-T-t path Gondwanaland Qiangtang and Lhasa Terranes Tibet

Quaternary Geology and Faulting in the Damxung-Yangbajain Basin

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Acta Geologica Sinica(English Edition) 2004年第1期78卷 273-282页

作者： WUZhonghai ZHAOXitao WUZhenhan jiangwan HUDaogong zhouChunjing InstituteofGeomechanics ChineseAcademyofGeologicalSciencesBeijing100081 InstituteofGeologyandGeophysics ChineseAcademyofSciencesBeijing100029

The detailed geological mapping, conducted in the Damxung-Yangbajain basin, shows that there are many types of deposits formed since the Pliocene. The oldest sediments are formed during the Pliocene. The most prominent sediments are three sets of moraines and fluvioglacial deposits. The ESR, U-series and OSL dates indicate they are formed about 700-500 ka B.P., 250-125 ka B.P. and 75-12 ka B.P. respectively and indicate that there are three glacial periods since the mid-Pleistocene in the Nyainqentanglha Range. Along the southeast side of the Nyainqentanglha Range, the main southeast dipping fault zone which bounds the Damxung-Yangbajain Graben on its western edge was mapped. The fault zone consists of three secondary fault zones and their initiation ages that the fault zones became active gradually decrease southeastward. Prominent faulting occurred in about 700-500 ka B.P., 350-220 ka B.P., -140 ka B.P. and 70-50 ka B.P. since the mid-Pleistocene. The height of fault scarps which offset the sediments formed since the mid-Pleistocene suggest that the vertical slip rates change between 0.4 -2 mm/a and the cumulative average vertical movement at rates of 1.1±0.3 mm/a during the Quaternary period and the Holocene vertical throw rate is 1.4±0.6 mm/a along the fault zones on the western side of the Damxung-Yangbajain Graben.

关键词： Qinghai-Tibet plateau Nyainqentanglha north-south trending graben active fault glaciation

SHRIMP U-Pb zircon dating on Nyainqentanglha granite in central Lhasa block

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Chinese Science Bulletin 2004年第1期49卷 76-82页

作者： LIUQisheng WUZhenhan HUDaogong YEPeisheng jiangwan WANGYanbin ZHANGHancheng InstituteofGeomechanics InstituteofGeologyChineseAcademyofGeologicalSciencesBeijing100081China BeijingSHRIMPCenter InstituteofGeologyChineseAcademyofGeologicalSciencesBeijing100037China ChinaUniversityofGeosciences Beijing100083China

The Nyainqentanglha granite, a batholith with an area of 1500 km^2 in the central Lhasa block, comprises mainly medium-fine-grained biotite monzonitic granite and medium-coarse-grained biotite monzonitic granite. Their contact relationship suggests that the medlum-fine-grained biotite monzonitic granite was crystallized earlier than the medium-coarse-grained monzonitic granite. A SHRIMP U-Pb dating on zircons from representative samples of the batholith shows that the crystallization age of the medium-fine-grained biotite monzonitic granite is 18.3 Ma and that of the medium-coarse-grained monzonitic granite is 11.01 Ma. The emplacement and crystallization of the Nyainqentanglha granite, the youngest granite batholith ever known inside the Lhasa block, have a close relationship with the collisional orogeny, crustal thickening, plateau uplifting,E-W crustal extension and have a dynamic genetic relationship with the crustal partial melting.

关键词：锆石花岗岩拉萨青藏高原

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我国大气电学研究的最新进展

大气科学 2024年第1期48卷 51-75页

作者：郄秀书朱江皖底绍轩骆烁名黄子凡刘冬霞张鸿波袁善锋刘明远孙竹玲徐晨孙春发王东方蒋如斌杨静中国科学院大气物理研究所中层大气和全球环境探测重点实验室(LAGEO) 北京100029 中国科学院大学地球与行星科学学院北京100049

大气电学主要研究地球大气和近地空间发生的电学过程及其机理和影响,其核心研究内容是雷电物理和雷暴电学。自1980年代以来,中国大气电学研究不断取得新的进展,特别是近年来,得益于高时间分辨率雷电探测技术的进步,大气电学研究不仅在... 详细信息

大气电学主要研究地球大气和近地空间发生的电学过程及其机理和影响,其核心研究内容是雷电物理和雷暴电学。自1980年代以来,中国大气电学研究不断取得新的进展,特别是近年来,得益于高时间分辨率雷电探测技术的进步,大气电学研究不仅在雷电物理学和雷暴云电荷结构方面取得了重要成果,也在雷电和雷暴对近地空间的影响、强对流天气的雷电特征、以及雷电资料同化和预警预报等方面取得了重要进展。本文从六个方面对近五年来大气电学的主要研究进展进行回顾,包括高精度雷电探测和定位技术、雷电物理过程和机制、雷暴对中上层大气的影响、雷暴云电荷结构的观测和数值模拟、强对流天气的雷电特征与预报、雷电对气候变化的影响与响应等,最后对大气电学未来发展进行展望。

关键词：大气电学雷暴雷电强对流天气资料同化和预警预报

Progress in the Study of Deep Profiles of Tibet and the Himalayas (INDEPTH)

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Acta Geologica Sinica(English Edition) 2004年第4期78卷 931-939页

作者： ZHAOWenjin ZHAOXun SHIDanian LIUKui jiangwan WUZhenhan XIONGJiayu ZHENGYukun ChineseAcademyofGeologicalSciences Beijing100037

This paper introduces 8 major discoveries and new understandings with regard to the deep structure and tectonics of the Himalayas and Tibetan Plateau obtained in Project INDEPTH, They are mainly as follows. (1) The upper crust, lower crust and mantle lithosphere beneath the blocks of the plateau form a 'sandwich' structure with a relatively rigid-brittle upper crust, a visco-plastic lower crust and a relatively rigid-ductile mantle lithosphere. This structure is completely different from that of monotonous, cold and more rigid oceanic plates. (2) In the process of north-directed collision-compression of the Indian subcontinent, the upper crust was attached to the foreland in the form of a gigantic foreland accretionary wedge. The interior of the accretionary wedge thickened in such tectonic manners as large-scale thrusting, backthrusting and folding, and magmatic masses and partially molten masses participated in the crustal thickening. Between the upper crust and lower crust lies a large detachment (e.g. the Main Himalayan Thrust in southern Tibet, 5-8 km thick) or a very thick shear-schistose zone (e.g. the Main Qiangtang Thrust-MQT in northern Tibet, up to 20 km thick), which causes the decoupling of the upper crust and lower crust and separation of tectonic activities. (3) During the collision-compression, the Indian mantle lithosphere was delaminated into two layers from where the crust thickened most rapidly (beneath the High Himalayas). The upper layer extends to 34.5°N and the lower layer to 33.5°. They have been underthrust to depths of 250-300 km into the asthenosphere. Meanwhile the Asian lithosphere (possibly the Qaidam terrane) has also been subducted southwards. Very thick mantle lithosphere does not exist beneath the plateau. (4) The oceanic lithosphere, in light of its lithology and dynamic behaviour, might be close to those of the continental lithosphere and its front might enter the asthenosphere before the continental lithosphere. (5) A 150-200 km deep low-velocity body below 35°N and a wide lo

关键词： INDEPTH Himalayas Tibetan Plateau crust structure mantle lithosphere structure

模块化危急心电图教学在住院医师规范化培训中的应用

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中国高等医学教育 2024年第2期 94-95页

作者：张芹周峥豪周炳炎曹江黄新苗海军军医大学附属长海医院上海200433 上海市虹口区江湾医院上海200081

针对心电图教学的难点和临床规培医师的思维特点,构建以心内科危急症主诉为核心的模块化心电图图库,并由此开展基于主诉的模块化心电图教学。课程结束,对比采用传统教学的对照组规培学员和采用模块化教学的试验组规培学员教学满意度和... 详细信息

针对心电图教学的难点和临床规培医师的思维特点,构建以心内科危急症主诉为核心的模块化心电图图库,并由此开展基于主诉的模块化心电图教学。课程结束,对比采用传统教学的对照组规培学员和采用模块化教学的试验组规培学员教学满意度和考核成绩,结果表明,试验组教学满意度高于对照组,差异具有统计学意义(P<0.05);试验组考核成绩高于对照组,差异具有统计学意义(P<0.05)。基于主诉的模块化心电图教学体系有利于提升心电图教学质量,有助于增强教学效果。

关键词：模块化心电图教学住院医师规范化培训问卷调查

同方期刊数据库博看期刊评论

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348例骨伤科疾病患者舌象观察与分析

上海中医药杂志 2008年第3期42卷 41-43页

作者：周勤上海市江湾医院上海200434

目的观察中医骨伤科疾病舌象表现,分析其与病证之关系,探讨舌诊应用之价值。方法统计施杞教授门诊348例病例,按舌象之舌质、舌苔、舌体及舌下静脉等类别观察,分析其与患者性别、年龄、病程、病位之间的关系。结果舌象与临床证候、患者... 详细信息

目的观察中医骨伤科疾病舌象表现,分析其与病证之关系,探讨舌诊应用之价值。方法统计施杞教授门诊348例病例,按舌象之舌质、舌苔、舌体及舌下静脉等类别观察,分析其与患者性别、年龄、病程、病位之间的关系。结果舌象与临床证候、患者个体有密切关系。结论舌诊是中医骨伤科辨证施治的重要手段和依据。

关键词：施杞舌诊骨伤科疾病

粤港澳大湾区地热异常空间分布特征的GIS分析

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深圳大学学报（理工版） 2023年第5期40卷 588-598,I0004-I0008页

作者：徐讲湾黄少鹏魏正安李勇义深圳大学土木与交通工程学院深地科学与绿色能源研究院广东深圳518060

粤港澳大湾区地热资源丰富,研究地热异常空间分布特征可为大湾区地热资源潜力评价和勘探开发决策提供科学支撑.基于地理信息系统技术构建了粤港澳大湾区大地热流、花岗岩分布、断裂、布格重力异常、航磁异常和居里面深度等空间数据层,... 详细信息

粤港澳大湾区地热资源丰富,研究地热异常空间分布特征可为大湾区地热资源潜力评价和勘探开发决策提供科学支撑.基于地理信息系统技术构建了粤港澳大湾区大地热流、花岗岩分布、断裂、布格重力异常、航磁异常和居里面深度等空间数据层,综合分析地热异常与地质和地球物理场特征的空间关联关系,揭示研究区地热异常的空间分布特征.分析结果表明,研究区内大地热流值大于75 mW/m^(2)、燕山期花岗岩边界或内部、与主断裂距离小于3 km、布格重力异常梯度大于1.6 mGal/km、航磁异常值为-5~5 nT及居里面深度小于15 km等区域,与地热异常区的空间关联密切;强地热异常的出现与居里面深度、燕山期花岗岩和主断裂关系最为密切.基于数据层分类,采用证据权重模型和加权信息量模型两种矿产资源预测方法对上述多元信息进行复合分析.研究表明,研究区内燕山期花岗岩分布广泛且岩石热导率较高的低山或丘陵区地区易出现强地热异常,具有这一特征的江门西部、肇庆中部、广州东北部、惠州东北部以及深圳等地的是粤港澳大湾区地热资源高潜力区.

关键词：地热学地理信息系统地热异常空间叠加分析空间关联证据权重模型加权信息量模型

AN EPIDEMIOLOGICAL SURVEY OF CHOLELITHIASIS IN SHANGHAI

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Journal of Shanghai Second Medical University(Foreign Language Edition) 2003年第1期15卷 62-64,70页

作者：叶忻韩天权王保钢肖志坤 Department of Surgery Jiangwan Hospital Shanghai 200434 China Department of Surgery Ruijin Hospital SSMU Shanghai 200025 China Department of Ultrasonic Diagnosis Jiangwan Hospital Shanghai 200434 China Department of Public Health Jiangwan Hospital Shanghai 200434 China

Objective:To obtain a general overview of gallstone disease in Shanghai.Methods 3415 citizens aged>20 in the community of Shanghai were randomly selected to undergo a clinical epidemiological study and an ultrasound examination to screen for cholielithiasis.Results:Overall prevalence rate of gallstones was 6.5% (8.6% in women and 5.1% in men).Among the 3415 persons investigated,65 had already undergone cholecystectomy.The perecentage of aymptomatic gallistone was 70.5%.Prevalence of gallstone diseases(gallstones plus cholecystectomy) increased with age significantly.Conclusion:Compared to the research in Shang hai ten years ago,especially for the persons older than 50 years.the gallstone disease has become more frequent.The proportion of asymptomatic gallstones and the awareness is increasing.

关键词：上海胆石症流行病学调查超声显像年龄