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“地质云”模式下大地电磁数据共享研究 被引量:3
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作者 冯斌 梁萌 +3 位作者 吴文鹂 张学利 杜炳锐 马娜 《物探与化探》 CAS 北大核心 2020年第4期796-802,共7页
采用"地质云"模式,开展了大地电磁数据共享研究,用以解决大地电磁数据的管理与共享问题。从架构设计、分类与管理、功能规划、在线处理等方面进行了探讨,重点介绍了大地电磁在线处理流程设计。最后以尼玛盆地工区电磁数据为... 采用"地质云"模式,开展了大地电磁数据共享研究,用以解决大地电磁数据的管理与共享问题。从架构设计、分类与管理、功能规划、在线处理等方面进行了探讨,重点介绍了大地电磁在线处理流程设计。最后以尼玛盆地工区电磁数据为应用实例搭建了原型系统。与传统数据共享系统相比,系统在遵循"地质云"标准的同时提出了一种新型电磁数据在线处理流程,为大地电磁专题服务在"地质云"共享提供了探索实践。 展开更多
关键词 大地电磁 共享服务 “地质云” 尼玛盆地
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基于空间数据库增量的地质图更新技术体系的构建思考 被引量:1
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作者 何学洲 陈秀法 +6 位作者 李玉龙 李仰春 高爱红 张伟波 王杨刚 张振芳 崔敏利 《中国矿业》 2023年第5期75-81,共7页
地质图作为地质调查各项工作最终表达的载体之一,因其具有认知能力强、内容表达丰富、应用便捷等特点而被广泛使用。为满足新发展阶段生态保护、工程建设、农业土地等新兴领域对地质图日渐旺盛的应用需求,适应大数据、云计算、移动互联... 地质图作为地质调查各项工作最终表达的载体之一,因其具有认知能力强、内容表达丰富、应用便捷等特点而被广泛使用。为满足新发展阶段生态保护、工程建设、农业土地等新兴领域对地质图日渐旺盛的应用需求,适应大数据、云计算、移动互联网等信息技术的发展,建立地质图编制新技术、新流程和新工艺十分必要。基于此,提出了现代建设“图库一体”的地质图增量更新技术体系的总体架构:一是基于地质数据增量更新的设计理念实现地质图的按需更新、快速更新;二是结合地质大数据技术和智能编图软件方法,加强综合地质数据整合汇聚和地质信息综合提取的能力;三是利用制图表达拓展智能编图技术方法,增强地质图的图面表达效果;四是通过“图库一体”技术实现原始地质数据与地质图成果的一体化存储与同步更新。通过构建地质图更新技术体系,对于及时快速提供地质图件,提高地质图生产效率,降低地质图生产成本具有重要的现实意义。 展开更多
关键词 地质 图库一体 增量更新 “地质云”平台 智能编图
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Formation, distribution, and nature of Picea mongolica in China 被引量:5
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作者 邹春静 韩士杰 +1 位作者 徐文铎 苏宝玲 《Journal of Forestry Research》 SCIE CAS CSCD 2001年第3期187-191,210,共5页
Picea mongolica is an endemic and endangered species in China. Ecosystem made of Picea mongolica is a special sandy forest ecosystem in China. It is found at ecotone between forest and steppe, or agricultural district... Picea mongolica is an endemic and endangered species in China. Ecosystem made of Picea mongolica is a special sandy forest ecosystem in China. It is found at ecotone between forest and steppe, or agricultural district and pastoral area. Based on investigation, this paper discussed the formation and distribution of Picea mongolica and studied its nature according to ecotone theory. It is clarified that Picea mongolica belongs to Picea meyeri series. That is to say, it became a local race through long-term adaptation to the local climate, then formed allopatric semi-species, and finally turned into a taxonomical species. Picea mongolica forest is a super zonal climax community developing in ecotone between forest zone and steppe zone. 展开更多
关键词 Picea mongolica Formation Distribution NATURE Sandy forest ECOTONE
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Micromorphology of landslide soil Case study on the Jibazi landslide in Yunyang in the Three Gorges Region, China 被引量:7
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作者 HE Yurong CUI Peng LIAO Chaolin ZHANG Baohua ZHAO Yu 《Journal of Mountain Science》 SCIE CSCD 2006年第2期147-157,共11页
Abstract: Landslide is one of natural catastrophes affecting national economy and people's livelihood. There are many reports on the forming mechanism and control of landslide, but the studies on micromorphology of ... Abstract: Landslide is one of natural catastrophes affecting national economy and people's livelihood. There are many reports on the forming mechanism and control of landslide, but the studies on micromorphology of landslide soil are few. There are many potential landslides in the Three Gorges Region in China. In this paper, the micromorphologic features of the Jibazi landslide soil in Yunyang in the Three Gorges Region of the Yangtze River were studied using routine methods, that is, soil micromorphology, X-ray diffraetometer and scanning electron microscope. The main conclusions are as follow: (1) The basic micromorphologic characteristics of the landslide soil are that the fine soil particles are commonly cohesive matrix, finer and lower content of skeleton grains, the microstructures are mainly types of phenocrystal gelatinization, densely chap and fissure structure. As a result, these micromorphologic features affect the discharging of soil water, favor the movement of landslide body and provide an internal basis of materials for the formation of landslide. (2) The concept on the forming material of landslide was proposed, and types of optical beamed clay aggregates, Fe-Mn isolates and glassy material were found in landslide-belt soil, which were remarkably different from the natural soil formation, and had some scientific significance in analyzing the forming mechanism of landslide and distinguishing me landslide-belt soil. (3) Some special micromorphologic and sub-micromorphologic characteristics, such as fingerprint microstructure, clay beamed bedding microstructure, oppressive microstructure, moulage microstructure and extending hole microstncture, could bring useful micromorphologic evidences for the observation and forecasting of landslide. The results mentioned above will bring helpful micromorphologic evidences for distinguishing slide soil, analyzing the formation mechanism of landslide, and monitoring and forecasting the occurrence of landslide. 展开更多
关键词 LANDSLIDE Microstructure forming material of landslide Three Gorges Region China
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Geological significance of nickeliferous minerals in the Fule Pb–Zn deposit, Yunnan Province, China 被引量:6
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作者 Zhenli Li Lin Ye +1 位作者 Yusi Hu Zhilong Huang 《Acta Geochimica》 EI CAS CSCD 2018年第5期684-690,共7页
Abstract The Fule Pb-Zn deposit is located in the Sichuan-Yunnan-Guizhou Province, and it is an important and giant low temperature metallogenic domain in China. In our research area, the Pb-Zn deposits are mainly hos... Abstract The Fule Pb-Zn deposit is located in the Sichuan-Yunnan-Guizhou Province, and it is an important and giant low temperature metallogenic domain in China. In our research area, the Pb-Zn deposits are mainly hosted in the Permian Yangxin Formation and are composed of dolostone and limestone. The distance between the ore bodies and the Permian Emeishan basalt ranged from 50 to 160 m. In this study, the nickel rich minerals, including vaesite, polydymite and millerite, were reported for the first time in the Fule deposit. These minerals occurred as xenomorphic mineral aggregate and were sporadically distributed in the sphalerite-galena-calcite vein, which is the main ore type in the deposit. Our study indicated that the paragenetic sequence of minerals in the Fule deposit is the following order: polydymite → vaesite → mil- lerite → sphalerite → galena → tetrahedrite (tennantite). The geological occurrence characteristics of those nicke- liferous minerals suggested that the Permian Emeishan basalt is a possible barrier layer of Pb-Zn ore-forming fluid, and it is an important source for the Ni and part of the Cu in the deposit. The Sichuan-Yunnan-Guizhou Pb-Zn mineralization province is a world-class production base of Pb and Zn, in which the Permian Emeishan basalt and Pb- Zn deposits have uniformly spatial distribution, but the relationship of mineralization between them is still under debate. This report provides new evidence for understanding the relationship between Pb-Zn mineral- ization and Permian Emeishan basalt in the Sichuan- Yunnan-Guizhou Pb-Zn mineralization province. 展开更多
关键词 Nickeliferous Permian Emeishan basalt Fule Pb-Zn deposit MVT deposit Barrier layer
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Phylogeography and Characteristics of Phosphorus Efficiency of Secondary Core Collection for Rice Landraces in Yunnan Province 被引量:3
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作者 ZENG Ya-wen DU Juan +5 位作者 PU Xiao-ying YANG Shu-ming YANG Tao WEI Ming-liang ZHANG Hao ZHOU Guo-hua 《Agricultural Science & Technology》 CAS 2011年第4期592-596,共5页
[Objective] The paper was to explore the causes of phosphorus(P)efficiency of rice in Yunnan Province,and to provide strategy for ecological and environmental protection.[Method]Using 703 accessions of secondary core ... [Objective] The paper was to explore the causes of phosphorus(P)efficiency of rice in Yunnan Province,and to provide strategy for ecological and environmental protection.[Method]Using 703 accessions of secondary core collections from 16 prefectures of five regions in Yunnan Province,two treatments of low available P(6.26mg/kg)versus normal P(available P 40mg/kg),and invalid P(available P 0.02 mg/kg)versus normal P(available P 70 mg/kg)were set,and zonal characteristics of phosphorus efficiency and the activation characteristics of invalid P of rice landraces were investigated.[Result] Phosphorus efficiency and the activation characteristics of invalid P in soils from rice landraces of Yunnan Province had the similar identification indexes,viz.the relative indexes of four traits(tillering ability or effective panicle,root weight,biomass,and straw weight)could be the screening indexes of gene type of secondary core collection with phosphorus efficiency,which also reflected the zonal characteristics of phosphorus efficiency and the activation characteristics of invalid P in soils of 16 prefectures among five regions.On the contrary,the relative panicle length,node length under panicle,leaf length,leaf width and plant height could only be the assistant indexes of identification for phosphorus efficiency.There were similar zonal characteristics between phosphorus efficiency and the activation characteristics of invalid P in soils of rice landraces in Yunnan Province.[Conclusion] The study had great importance to the conservation and utilization of biological diversity,which would make contribution to second green revolution of "less input,multiple output,promote health,and protect the environment". 展开更多
关键词 Phosphorus efficiency PHYLOGEOGRAPHY CHARACTERISTICS Secondary core collection Rice landraces
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Geology and fluid inclusion characteristics of Qilishan gold deposit in Zhaoyuan of Shandong,China
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作者 SONG Zilong DING Qingfeng ZHANG Yuan 《Global Geology》 2013年第4期177-183,共7页
The Qilishan gold deposit is located in the southern Zhaolai gold ore belt in the northwestern Jiaodong region.A total of seven gold ore bodies have been found in the mining area.Linglong gneissic biotite granite and ... The Qilishan gold deposit is located in the southern Zhaolai gold ore belt in the northwestern Jiaodong region.A total of seven gold ore bodies have been found in the mining area.Linglong gneissic biotite granite and the NE trending Lingbei fracture control the output and distribution of the gold deposit.The ore bodies with veined or irregular shape occur in the structural alteration zone.The ore bodies of different sizes are NE trending and SE dipping.The constituent minerals of the ores mainly include pyrite,chalcopyrite,native gold,electrum,argentite,matildite,hematite,quartz and calcite.The ores are characterized by metasomatic dissolution structure,as well as veined and brecciated structures.The ore-forming process is divided into four stages,namely quartz-,pyrite-,polymetallic-and carbonate stages.Study on fluid inclusion shows that the deposit is composed of gas-liquid two-phase inclusions (Ⅰ) and three-phase inclusions containing CO2 (Ⅱ),and that the former dominates.The homogenization temperature is 259.6℃-373.7℃ ; the salinity of three-phase inclusions containing CO2is 5.77%-9.84% (NaCl) ; the salinity of gas-liquid two-phase inclusions is 6.58%-8.54% (NaCl) ; and the estimated ore-forming pressure is 55.2-82.2 MPa.According to the nonlinear relationship between the depth and pressure of the fluid in the fracture zone,the ore-forming depth of the Qilishan gold deposit is calculated as 5.95-7.14 km.It is preliminarily determined that the deposit is a mesophilic and hypothermal gold deposit. 展开更多
关键词 fluid inclusion deposit characteristics hypothermal gold deposit Qilishan gold deposit
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Building a Comprehensive Well-off Society in Yunnan's Minority Areas A Study of the Prediction on the Differences in Life Quality Indexes
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作者 Yunhong GONG Lijiao WANG 《International Journal of Technology Management》 2015年第10期100-105,共6页
Based on the gray theory and GM (1, 1) model, the life quality indexes in next few years are predicted using the statistical data of the life quality indexes of Yunnan' s 8 minority areas in recent years and also c... Based on the gray theory and GM (1, 1) model, the life quality indexes in next few years are predicted using the statistical data of the life quality indexes of Yunnan' s 8 minority areas in recent years and also compared with the standard value (2020) of building the national well-off society, and the differences between them are measured and calculated. Thus, effective reference information is provided for the decision-making of government. 展开更多
关键词 Yunnan' s Minority Areas Life Quality Indexes GM(1 1) Prediction Model
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Ore genesis of Badi copper deposit, northwest Yunnan Province, China: evidence from geology, fluid inclusions, and sulfur, hydrogen and oxygen isotopes
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作者 Hejun Yin Jianguo Huang Tao Ren 《Acta Geochimica》 EI CAS CSCD 2018年第4期559-570,共12页
The Badi copper deposit is located in Shangjiang town, Shangri-La County, Yunnan Province. Tectonically, it belongs to the Sanjiang Block. Vapor-liquid two-phase fluid inclusions, CO2-bearing fluid inclusions, and dau... The Badi copper deposit is located in Shangjiang town, Shangri-La County, Yunnan Province. Tectonically, it belongs to the Sanjiang Block. Vapor-liquid two-phase fluid inclusions, CO2-bearing fluid inclusions, and daugh- ter-beating inclusions were identified in sulfide-rich quartz veins. Microthermometric and Raman spectroscopy studies revealed their types of ore-forming fluids: (1) low-tem- perature, low-salinity fluid; (2) medium-temperature, low salinity CO2-bearing; and (3) high-temperature, Fe-rich, high sulfur fugacity. The δ^18O values of chalcopyrite- bearing quartz ranged from 4.96‰ to 5.86%0, with an average of 5.40%0. The δD values of ore-forming fluid in equilibrium with the sulfide-bearing quartz were from - 87‰ to - 107‰, with an average of - 97.86%0. These isotopic features indicate that the ore-forming fluid is a mixing fluid between magmatic fluid and meteoric water. The δ^34S values of chalcopyrite ranged from 13.3‰ to 15.5‰, with an average of 14.3‰. Sulfur isotope values suggest that the sulfur in the deposit most likely derived from seawater. Various fluid inclusions coexisted in the samples; similar homogenization temperature to different phases suggests that the Badi fluid inclusions might have been captured under a boiling system. Fluid boiling caused by fault activity could be the main reason for the mineral precipitation in the Badi deposit. 展开更多
关键词 Badi copper deposit Fluid inclusion Sulfurisotope Hydrogen and oxygen isotope Ore genesis
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Revised Ti-in-biotite geothermometer for ilmeniteor rutile-bearing crustal metapelites 被引量:22
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作者 吴春明 陈泓旭 《Science Bulletin》 SCIE EI CAS CSCD 2015年第1期116-121,共6页
In the present study, the Ti-in-biotite geother- mometer was revised using more than 300 natural rutile- or ilmenite-bearing metapelites collected worldwide. The formulation was empirically calibrated as ln[T(℃)]= ... In the present study, the Ti-in-biotite geother- mometer was revised using more than 300 natural rutile- or ilmenite-bearing metapelites collected worldwide. The formulation was empirically calibrated as ln[T(℃)]= 6.313 +0.22 41n(XTi ) -0.2881n(XFe ) -0. 4491n(XMg) + 0.15P (GPa), with Xj=j/(Fe+Mg+Al^Ⅵ+Ti) in biotite, assuming ferric iron content of 11.6 mol% of the total iron in biotite. This thermometer is consistent with the well-calibrated garnet-biotite thermometer within error of i50 ℃ for most of the calibrant samples and can successfully distin- guish systematic temperature changes of different meta- morphic zones in both prograde and inverted metamorphic terranes as well as thermal contact aureoles. Thus, the thermometer truthfully reflects real geologic conditions and can be applied to TiO2-saturated metapelites metamor- phosed at the crustal level within the calibration ranges (450-840 ℃, 0.1-1.9 GPa, XTi = 0.02-0.14 in biotite). 展开更多
关键词 Ti content BIOTITE Calibration -Geothermometer Application Error
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Metamorphic, deformation, fluids and geological significance of low-temperature retrograde mylonites of Diancangshan metamorphic massif along Ailaoshan-Red River strike-slip fault zone, Yunnan, China 被引量:4
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作者 Xuemei CHENG Shuyun CAO +4 位作者 Junyu LI Zunpu YU Yanlong DONG Meixia LV Junlai LIU 《Science China Earth Sciences》 SCIE EI CAS CSCD 2018年第8期1023-1041,共19页
Diancangshan metamorphic massif is one of the four metamorphic massifs developed along the Ailaoshan-Red River strike-slip fault zone, Yunnan, China. It has experienced multi-stage metamorphism and deformation, especi... Diancangshan metamorphic massif is one of the four metamorphic massifs developed along the Ailaoshan-Red River strike-slip fault zone, Yunnan, China. It has experienced multi-stage metamorphism and deformation, especially since the late Oligocene it widely suffered high-temperature ductile shear deformation and exhumation of the metamorphic rocks from the deep crust to the shallow surface. Based on the previous research and geological field work, this paper presents a detailed study on deformation and metamorphism, and exhumation of deep metamorphic rocks within the Diancangshan metamorphic massif,especially focusing on the low-temperature overprinted retrogression metamorphism and deformation of mylonitic rocks. With the combinated experimental techniques of optical microscope, electron backscatter diffraction attachmented on field-emission scanning electron microscopy and cathodoluminescence, our contribution reports the microstructure, lattice preferred orientations of the deformed minerals, and the changes of mineral composition phases of the superposition low-temperature retrograde mylonites. All these results indicate that:(1) Diancangshan deep metamorphic rock has experienced early high-temperature leftlateral shear deformation and late extension with rapid exhumation, the low-temperature retrogression metamorphism and deformation overprinted the high-temperature metamorphism, and the high-temperature microstructure and texture are in part or entirely altered by subsequent low-temperature shearing;(2) the superposition of low-temperature deformation-metamorphism occurs at the ductile-brittle transition; and(3) the fluid is quite active during the syn-tectonic shearing overprinted lowtemperature deformation and metamorphism. The dynamic recrystallization and/or fractures to micro-fractures result in the strongly fine-grained of the main minerals, and present strain localization in micro-domians, such as micro-shear zones in the mylonites. It is often accompanied by the decrease of rock strength and finally influences the rheology of the whole rock during further deformation and exhumation of the Diancangshan massif. 展开更多
关键词 Low-temperature mylonites Brittle-ductile transition Microstructure Fluid Exhumation Rheological weakening
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Temperatures of dolomitizing fluids in the Feixianguan Formation from the Northeastern Sichuan Basin 被引量:4
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作者 HU ZuoWei HUANG SiJing +3 位作者 LI ZhiMing QING HaiRuo FAN Ming LAN YeFang 《Science China Earth Sciences》 SCIE EI CAS 2012年第10期1627-1640,共14页
The discovery of natural gas reservoirs from the Triassic Feixianguan Formation in the Northeastern Sichuan Basin is an important breakthrough in the field of marine carbonate rocks for Chinese oil and gas exploration... The discovery of natural gas reservoirs from the Triassic Feixianguan Formation in the Northeastern Sichuan Basin is an important breakthrough in the field of marine carbonate rocks for Chinese oil and gas exploration in recent years.Because of the dolomite-hosted reservoirs in the Feixianguan Formation,these dolomites and their formation mechanisms have been a research focus for sedimentary geologists and petroleum geologists.Based on the homogenization temperatures of fluid inclusions,oxygen isotopic composition and their calculated temperatures,and the burial and thermal history of the typical well,it is considered that the majority of dolomites are formed by low-temperature dolomitizing fluids in the Triassic Feixianguan Formation,Northeastern Sichuan Basin.Only a minority of dolomites are formed by high-temperature dolomitizing fluids.The ending depth interval of low-temperature dolomitizing fluids was about 1000-2500 m,of which the correspondingly ending timing interval was approximately from early-middle Middle Triassic to early-middle Late Triassic.The main depth interval of high-temperature dolomitizing fluids was about 3200-4500 m,of which the correspondingly main timing interval was approximately early-middle Middle Jurassic.The low-temperature and high-temperature dolomitizing fluids have different meanings to the formation and evolution of the pore volumes of dolomite reservoirs in the Feixianguan Formation,Northeastern Sichuan Basin. 展开更多
关键词 TRIASSIC Feixianguan Formation DOLOMITE fluid inclusion oxygen isotope Northeastern Sichuan Basin
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The relationship between extension of lower crust and displacement of the shelf break 被引量:3
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作者 ZHANG YunFan SUN Zhen PANG Xiong 《Science China Earth Sciences》 SCIE EI CAS 2014年第3期550-557,共8页
With deep sea petroleum explorations become more and more popular,some geological phenomena have emerged:extension of lower crust and upper crust is inhomogeneous;shelf break has been moved rapidly after crustal stret... With deep sea petroleum explorations become more and more popular,some geological phenomena have emerged:extension of lower crust and upper crust is inhomogeneous;shelf break has been moved rapidly after crustal stretching.These geological phenomena are important to the continental margin evolution.To investigate the thinning of the whole crust and the contribution of the upper crust versus the lower crust to the crustal stretching since the Cenozoic,we calculated the stretching factors of the upper and the lower crust based on the 13 seismic lines in the Baiyun Sag from CNOOC.The results indicated that the whole crustal thickness decreases seaward while the whole crustal stretching factor increases from shelf to slope.Our calculations showed that the lower crustal stretching factor is higher than that of the upper crust in the Baiyun Sag.In the Cenozoic,deformation of the Baiyun Sag is controlled mainly by ductile shearing rather than brittle shearing.Based on the numerical modeling,we can conclude the initial crust in the Baiyun Sag is thermally attenuated.The stretching factor(β)of the lower crust increases from the north to the south of the continental margin,indicating two stretching centers:the Baiyun Sag and the Liwan Sag.The geometry of the shelf break and theβisoline trap have the similar trend in 23.8 and 13.8 Ma,both located in the intense deforming zone of the lower crust,and therefore we conclude the stretching and flowing of the lower crust cause the displacement of the shelf break before and after 23.8 Ma. 展开更多
关键词 Baiyun Sag shelf break stretching factor lower crustal extension
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Wood textures in Jinman copper deposit in western Yunnan and their genetic implications 被引量:1
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作者 刘家军 李朝阳 +5 位作者 张乾 潘家永 刘玉平 刘显凡 刘世荣 杨伟光 《Science China Earth Sciences》 SCIE EI CAS 2001年第6期545-554,共10页
Jinman vein copper deposit in western Yunnan occurs in a salt-bearing red clastic rock formation composed of sandstone, siltstone and shale. Wood texture is considerably developed in the ores. The metallic minerals ma... Jinman vein copper deposit in western Yunnan occurs in a salt-bearing red clastic rock formation composed of sandstone, siltstone and shale. Wood texture is considerably developed in the ores. The metallic minerals making up the wood textures mainly include pyrite, chalcopyrite and bornite. Studies on the samples and examination of their micrographs and electron micrographs have confirmed that they belong to xenoxylon, reflecting that the ore-hosting rock series is the product of sedimentation in the terrestrial environment. Organic geochemistry and sulfur and carbon isotopic composition data indicate that the formation of the deposit is substantially related with underground hot brines and biological processes. 展开更多
关键词 vein copper deposit wood texture biological process western Yunnan China
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Mineralogical feature and geological significance of muscovites from the Longyuanba Indosinian and Yanshannian two-mica granites in the eastern Nanling Range 被引量:4
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作者 TAO JiHua LI WuXian +1 位作者 CAI YuanFeng CEN Tao 《Science China Earth Sciences》 SCIE EI CAS 2014年第6期1150-1157,共8页
Emplacement P-T condition estimations using granites are important for understanding metamorphic and erosional processes of orogenic belt.Granites are widespread in South China and a majority of them are peraluminous.... Emplacement P-T condition estimations using granites are important for understanding metamorphic and erosional processes of orogenic belt.Granites are widespread in South China and a majority of them are peraluminous.Particularly,over 91%of the Indosinian granites exposed in the region are peraluminous in composition.It is extremely hard to determine the pressure of intrusion of these peraluminous granites due to the absence of amphibole,a good mineral barometer commonly identified in metaluminous granites.Muscovite is a common mineral in peraluminous granites,certain kind of it could be used as a mineral barometer to constrain the emplacement pressure of peraluminous granites.In this paper,results of petrographic and geochemical studies of muscovites from the Indosinian and early Yanshanian two-mica granites at the Longyuanba in the eastern Nanling Range are reported.Based on petrographic studies,the primary muscovite can be discriminated from the secondary muscovites.Muscovites from the Indosinian two-mica granites are enriched in Ti,Al,Mg,and Na,and depleted in Fe and Mn.Geochemically,these muscovites were considered as primary,whereas those from the Yanshanian two-mica granites fall into the area of secondary muscovite on discrimination diagrams.Barometer estimations show that pressures calculated for primary muscovites are accurate,but those calculated for secondary muscovites are overestimated.The average pressure of emplacement of the Longyuanba Indosinian two-mica granites is 5.9 kbar,corresponding to^19 km in depth,suggesting that the Indosinian granitic magmas were probably generated by partial melting of a thickened crust root in a compressional tectonic setting. 展开更多
关键词 emplacement depth MUSCOVITE peraluminous granites Longyuanba complex Nanling Range
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Changes in Soil Physicochemical Properties Following Land Use Change from Paddy Fields to Greenhouse and Upland Fields in the Southeastern Basin of Dianchi Lake,Yunnan Province,China 被引量:4
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作者 N.MORITSUKA T.NISHIKAWA +4 位作者 S.YAMAMOTO N.MATSUI H.INOUE LI Kun-Zhi T.INAMURA 《Pedosphere》 SCIE CAS CSCD 2013年第2期169-176,共8页
Paddy fields in the southeastern basin of Dianchi Lake have rapidly changed to greenhouses since 1999. A total of 61 surface soil samples, including 43 greenhouse soils, 12 upland soils, and 6 paddy soils, were collec... Paddy fields in the southeastern basin of Dianchi Lake have rapidly changed to greenhouses since 1999. A total of 61 surface soil samples, including 43 greenhouse soils, 12 upland soils, and 6 paddy soils, were collected from a flat lowland area mainly used for agricultural production fields in the southeastern basin of Dianchi Lake. Analyses of the soil samples indicated that the greenhouse soils were characterized by a lower organic matter content, lower pH, and higher soluble nutrients than the paddy soils in the area. The lower organic matter content of the greenhouse soils was ascribed to environmental or management factors rather than the clay content of the soil. Accumulation of soluble nutrients, especially inorganic N, was due to over-application of fertilizers, which also caused soil acidification. The average amount of readily available N, P, and K accumulated in the greenhouse soils was estimated to be equal to or higher than the annual input of these nutrients as a fertilizer, indicating that a reduction in fertilizer application was possible and recommended. In contrast, a very low available Si content was observed in the paddy soils, suggesting the need for Si application for rice production. 展开更多
关键词 available Si greenhouse soils inorganic N phosphorus SALINIZATION
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Diversity of Mesozoic tin-bearing granites in the Nanling and adjacent regions,South China:Distinctive mineralogical patterns 被引量:15
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作者 WANG RuCheng XIE Lei +2 位作者 LU JianJun ZHU JinChu CHEN Jun 《Science China Earth Sciences》 SCIE EI CAS CSCD 2017年第11期1909-1919,共11页
The Nanling and adjacent regions of South China host a series of tin deposits related to Mesozoic granites with diverse petrological characteristics. The rocks are amphibole-bearing biotite granites, or (topaz-) alb... The Nanling and adjacent regions of South China host a series of tin deposits related to Mesozoic granites with diverse petrological characteristics. The rocks are amphibole-bearing biotite granites, or (topaz-) albite-lepidolite (zinnwaldite) granites, and geochemically correspond to mealuminous and peraluminous types, respectively. Mineralogical studies demonstrate highly distinctive and critical patterns for each type of granites. In mealuminous tin granites amphibole, biotite and perthite are the typical rock-forming mineral association; titanite and magnetite are typical accessory minerals, indicating highjO2 magmatic conditions; cassiterite, biotite and titanite are the principal Sn-bearing minerals; and pure cassiterite has low trace-element contents. However, in peraluminous tin granites zirmwaldite-lepidolite, K-feldspar and albite are typical rock-forming minerals; topaz is a common accessory phase, indicative of high peraluminity of this type of granites; cassiterite is present as a uniquely important tin mineral, typically rich in Nb and Ta. Mineralogical distinction between the two types of tin granites is largely controlled by redox state, volatile content and differentiation of magmatic melts. In oxidized metaluminous granitic melts, Sn4+ is readily concentrated in Ti-bearing rock-forming and accessory minerals. Such Sn-bearing minerals are typical of oxidized tin granites, and are enriched in granites at the late fractionation stage. In relatively reduced peraluminous granitic melts, Sn2+ is not readily incorporated into rock-forming and accessory minerals, except for cassiterite at fractionation stage of granite magma, which serves as an indicator of tin mineralization associated with this type of granites. The nature of magma and the geochemical behavior of tin in the two types of granites thus result in the formation of different types of tin deposits. Metaluminous granites host disseminated tin mineralization, and are locally related to deposits of the chlorite quartz-vein, greisen, and skarn types. Greisen, skarn, and quartz-vein tin deposits can occur related to peraluminous granites, but disseminated mineralization of cassiterite is more typical. 展开更多
关键词 Metaluminous tin granites Peraluminous granites Mineral assemblages Mineralogical indication of mineralization Nanling and adjacent regions
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