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Geochronology and geochemistry of Cretaceous-Eocene granites,Tengchong Block(SW China):Petrogenesis and implications for Mesozoic-Cenozoic tectonic evolution of Eastern Tethys

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Geoscience Frontiers 2022年第2期13卷 214-236页

作者： Yongqing Chen Guangjie Li luxue Qin yingxiang lu Chengxing Jiang School of Earth Sciences and Resources China University of Geosciences(Beijing)Beijing 100083China Yunnan Geological Survey Kunming 650051China

The Early Cretaceous-Early Eocene granitoids in the Tengchong Block record the evolutionary history of the Mesozoic-Cenozoic tectono-magmatic evolution of Eastern Tethys.(a)The Early Cretaceous granitoids with relatively low(^(87)Sr/^(86)Sr)iratios of 0.7090-0.7169 andε_(Nd)(t)values of-9.8 to-7.8 display metaluminous,calc-alkaline dominated by I-type granite affinity and hybrid mantle-crust geochemical *** may have been derived from melting of the subducted Meso-Tethyan BangongNujiang oceanic crust with terrigenous sediments in an arc-continent collisional setting.(b)The Late Cretaceous-Paleocene granitoids with relatively high(^(87)Sr/^(86)Sr)iratios of 0.7109-0.7627,andε_(Nd)(t)values of-12.1 to-7.9 exhibit metaluminous to peraluminous,calc-alkaline dominated by S-type granite affinity and hybrid Lower-Upper crust geochemical signatures,which may be originated from partial melting of the Meso-Proterozoic continental crust in the collision setting between the Tengchong Block and Baoshan Block.(c)The Early Eocene granitoids have metaluminous,calc-alkaline I-type and S-type granites dual affinity,with relatively high(^(87)Sr/^(86)Sr)iratios of 0.711-0.736,ε_(Nd)(t)values of-9.4 to-4.7,showing crust-mantle mixing geochemical *** may have been originated from partial melting of the late Meso-Proterozoic upper crustal components mixed with some upper mantle material during the ascent process of mantle magma caused by the subduction of the Neo-Tethyan Putao-Myitkyian oceanic crust,and collision between the Western Burma Block and the Tengchong *** is these multi-stage subductions and collisions that caused the spatial and temporal distribution of the granitic rocks in the Tengchong Block.

关键词： Zircon U-Pb geochronology Sr-Nd-Pb isotopes Granites in the Tengchong Block Tectono-magmatic evolution Eastern Tethys tectonic domain SW China

Zircon SHRIMP U-Pb geochronology,geochemistry and petrogenesis of the upper Eocene Shuangmaidi peraluminous granite in Baoshan Block,Western Yunnan Terrain,southwestern China

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Science China Earth Sciences 2011年第7期54卷 982-997页

作者： HUANG JingNing CHEN YongQing ZHAI XiaoMing lu yingxiang XIE YongFu CHENG ZhiZhong School of Earth Science andMineral Resources China University ofGeosciences Beijing 100083 China College of Lake County 19351 W. Washington St Grayslake IL 60030 USA Yunnan Geological Survey Kunming 650051 China Baoshan Branch Company Yunnan Company of Mineral Resources Baoshan 678000 China Institute of Exploration Geophysics and Geochemistry Chinese Academy of Geological Sciences Langfang 065000 China The Geological Museum of China Beijing 100034 China

The Baoshan Block is tectonically located in the middle segment of the Sibumasu plate. Granitic magmatism within the Baoshan Block has been considered weakly active due mainly to very limited exposures during the Himalaya orogenic episode. The geochronological study on the buried Shuangmaidi granite has confirmed the existence of the Cenozoic granitoids in the Baoshan Block. The present study indicates that：（1） It is medium- to coarse-grained two mica phyric granite, characterized by high SiO2 （73.55%-77.16%） and low CaO （0.34%-1.38%） contents, with a total alkalis （K2O＋Na2O） of 5.22%-8.03%, K2O/Na2O ratios of 0.24-1.79, and total rare earth elements （ZREE） of the granite between 85 and 125 ppb. All samples are enriched in light REE and exhibit medium negative Eu anomalies; and they show pronounced negative anomalies in Ba, Sr, Ti, and Nb but significant positive anomalies in K, Rb, U, Th, and Pb on mantle-normalized trace element patterns, indicating typi-cally peraluminous to strongly peraluminous S-type granite. （2） The zircon SHRIMP U-Pb ages of the granite are 36.27±0.48 Ma for the samples from ZK7-1 and 35.78±0.49 Ma for those from ZK0-1, respectively. The similar zircon ages from these two drill cores may suggest that the granite samples come from the same buried pluton. （3） 206pb/204pb values of the granite vary from 20.115 to 25.359, 207pb/204pb from 15.776 to 16.160, and 208pb/204pb from 39.236 to 41.285, showing the characteristics of radio- active lead anomaly of the upper crust. The （87Sr/86Sr）i values calculated on the average age of the two-mica orthoclase granite （36 Ma） range from 0.72524 to 0.77503 and eNd（t） values vary from -10.9 to -11.7. These data, along with the depleted-mantle Nd modal ages of 1.73-1.80 Ga, imply that the granites might have formed from partial melting of the Precambrian crystal basements. （4） On the Hf-Rb-Ta diagram, almost all the samples fall within the field of post-collision tectonic setting. The CaO/Na2O and A1203/TiO

关键词： Upper Eocene peraluminous granite elements and Sr-Nd-Pb isotopic geochemistry Himalayan post-collision orogenic setting Baoshan Block southwestern China

Zircon U-Pb Ages of the Granodioritic Porphyry in the Laba Molybdenum Deposit,Yunnan,SW China and Its Geological Implication

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Acta Geologica Sinica(English Edition) 2014年第4期88卷 1183-1194页

作者： YU Haijun LI Wenchang YIN Guanghou lu yingxiang CAO Xiaomin HUANG Dingzhu DONG Tao ZHANG Youming Yunnan Geological Survey Bureau

The Geza island-arc is a well-known mineralization concentration area, part of the Sanjiang Domain at the east margin of the Tibetan Plateau. In recent years, several Late Yanshanian granitic intrusions and associated deposits have been found in this region, the largest one of which in the Shangri-La region is the Laba molybdenum deposit. Previous studies suggested that the timing of the Laba mineralization is 85 ±2 Ma. However, the ages of the granodioritic porphyry remain unknown. In this study, LA-ICP-MS U-Pb dating of zircons from three samples of the molybdenite-bearing granodioritic porphyry has been conducted with resulting dates of 85.00±0.23 Ma （MSWD = 0.58）, 85.28 ± 0.28 Ma （MSWD = 1.12）, and 84.83 ± 0.26 Ma （MSWD = 0.79）, respectively, indicating that these granodioritie porphyries formed in the Late Yanshanian around -85 Ma. Combined with the geological features of the mineralization, the Laba deposit is spatially, temporally, and probably genetically associated with the granodioritic porphyries. In addition, the ages of the Laba deposits are consistent with the other Late Yanshanian intrusions and mineralization, suggesting that the mineralization was probably generated under an intra-plate extensional environment during the Late Cretaceous.

关键词： geochronology mineralogy U-Pb dating of zircons Geza island-arc Cretaceous,molybdenum Yunnan province Tibetan plateau

Exhumation of the Late Cretaceous Ore-forming Porphyries in Zhongdian Area,Northwestern Yunnan:Evidence from Fission Track Analysis

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Acta Geologica Sinica(English Edition) 2021年第5期95卷 1786-1787页

作者： LIU Xuelong YANG Zhiming lu yingxiang ZHANG Na DONG Leilei JIAO Qianqian CHEN Jianhang YANG Fucheng Kunming University of Science and Technology Kunming 650093China Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China Yunnan Geological Survey Kunming 650051China China University of Geosciences Beijing 100083China

Objective The Zhongdian area,Yunnan Province,is located in the southern of the Yidun Island arc belt in the TethysHimalayan metallogenic area,and is one of the important copper polymetallic mineral resource bases in *** on the previous studies(Liu et al.,2014),this paper discusses the Late Cretaceous tectono-thermal events in Zhongdian,to reconstruct the framework of their evolution and to restore the uplift history of representative ore-forming porphyries.

关键词： Cretaceous China. bases

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感潮河道桥梁和码头工程群对行洪累积影响

水利水电科技进展 2021年第2期41卷 49-56页

作者：陈珺于明田邓丽华陆迎香河海大学水文水资源与水利工程科学国家重点实验室江苏南京210098 河海大学水利水电学院江苏南京210098 重庆西科水运工程咨询中心重庆400016

以宁波甬江流域感潮河段所建工程群为研究对象,基于Delft3D数学模型开展了典型洪潮条件下桥梁和码头群对河道行洪的累积影响研究,对比分析单类工程群和两类工程群对河道洪水位和流速的影响。结果表明:桥梁和码头群对河道行洪存在累积影... 详细信息

以宁波甬江流域感潮河段所建工程群为研究对象,基于Delft3D数学模型开展了典型洪潮条件下桥梁和码头群对河道行洪的累积影响研究,对比分析单类工程群和两类工程群对河道洪水位和流速的影响。结果表明:桥梁和码头群对河道行洪存在累积影响,位置集中在宁波大学上游的甬江、奉化江和姚江河段;在两类工程群单独作用下均存在水位(流速)增加或减小的区域,桥梁和码头群的联合作用使得水位(流速)变化幅度更大,但不是两类工程群影响幅度的简单叠加;在两类工程群单独作用下水位(流速)变化相反的区域,桥梁和码头群的联合作用下水位(流速)的变化幅度减小。

关键词：感潮河流桥梁和码头群工程群行洪影响累积影响数值模拟

黄河夺淮对淮河中下游影响及防洪治理措施综述

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人民长江 2021年第11期52卷 9-15页

作者：陈珺于明田邓丽华陆迎香河海大学水利水电学院江苏南京210098 重庆西科水运工程咨询中心重庆400016

历史上黄河夺淮对淮河造成了重大影响,导致淮河中下游洪涝灾害频发,目前黄河虽已北归,但其带来的不利影响仍延续至今。阐述了黄河夺淮对淮河水系和洪泽湖演变的影响,回顾了1949年至今中国在淮河治理方面的成就,指出了淮河流域目前存在... 详细信息

历史上黄河夺淮对淮河造成了重大影响,导致淮河中下游洪涝灾害频发,目前黄河虽已北归,但其带来的不利影响仍延续至今。阐述了黄河夺淮对淮河水系和洪泽湖演变的影响,回顾了1949年至今中国在淮河治理方面的成就,指出了淮河流域目前存在的洪涝问题,并对今后应采取的淮河治理措施进行了分析。结果表明:为了治理淮河的洪涝灾害,应当采取扩大中游河槽、开挖引河、河湖分离、建设入海水道二期工程等工程措施,同时应与非工程措施相结合,并综合考虑水资源、航运等影响,开展多目标的综合治理。

关键词：黄河夺淮洪涝灾害治理措施淮河流域

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滇西北格咱火山-岩浆弧斑岩成矿作用

岩石学报 2011年第9期27卷 2541-2552页

作者：李文昌尹光侯余海军卢映祥刘学龙云南省地质调查局昆明650051 中国地质大学北京100083

处于义敦岛弧南端的格咱火山-岩浆弧,印支期以大规模中酸性火山-岩浆岩呈北西向带状展布为特征,本文根据火山-岩浆岩的分布、类型、时代与构造环境、成矿作用等,将该岩浆岩带细分为西部烂泥塘-春都斑岩成矿带和东部亚杂-普朗斑岩成矿带... 详细信息

处于义敦岛弧南端的格咱火山-岩浆弧,印支期以大规模中酸性火山-岩浆岩呈北西向带状展布为特征,本文根据火山-岩浆岩的分布、类型、时代与构造环境、成矿作用等,将该岩浆岩带细分为西部烂泥塘-春都斑岩成矿带和东部亚杂-普朗斑岩成矿带,并阐述了西斑岩带岩浆侵位时间较东斑岩带早15～25Myr以及2个成矿带不同的成矿特征,提出该区燕山晚期叠加了1期广泛的钼(钨、铜)成矿作用,以S型花岗岩侵位,南北向叠加于印支期岛弧岩浆岩带上,由北而南从出露至半隐伏、隐伏状,在云南境内圈出休瓦促、热林、红山、铜厂沟等多个花岗(斑)岩体,蚀变花岗(斑)岩内发育石英脉型和蚀变岩型钼矿化,围岩中以热液脉型沿断裂带、不同岩性界面等成矿。以往研究,休瓦促、热林成岩年龄分别为84.4±1.1Ma和81.7±1.1Ma,成矿年龄分别为83±1Ma和81.2±2.3Ma.(李建康等,2007;尹光侯等,2009);本次在红山铜矿深部隐伏岩体中获辉钼矿Re-Os等时线年龄80.2Ma。研究认为,燕山期岩体成矿,仍然表现出岩体由内向外(由深到浅)形成斑岩型钼(铜)矿→接触带夕卡岩型钼(铜)矿→外围角岩钼(铜)矿、热液脉状铜铅锌矿等成矿系列,据此进行缺位预测,为下步找矿指出了方向。

关键词：格咱弧印支期燕山期斑岩成矿作用

中甸弧燕山晚期成矿事件的Re-Os定年及成矿规律研究

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岩石学报 2007年第10期23卷 2415-2422页

作者：李建康李文昌王登红卢映祥尹光侯薛顺荣中国地质科学院矿产资源研究所北京100037 云南省地质调查院昆明650011

中甸弧是义敦岛弧的南延部分,是我国重要的铜铅锌钼多金属成矿区。在该地区,相对于印支期成矿事件,燕山晚期成矿事件的研究程度和重视程度均不够。中甸弧燕山晚期形成的矿床主要为休瓦促钨钼矿床、热林多金属矿点和红山多金属矿床。本... 详细信息

中甸弧是义敦岛弧的南延部分,是我国重要的铜铅锌钼多金属成矿区。在该地区,相对于印支期成矿事件,燕山晚期成矿事件的研究程度和重视程度均不够。中甸弧燕山晚期形成的矿床主要为休瓦促钨钼矿床、热林多金属矿点和红山多金属矿床。本文通过辉钼矿Re-Os定年技术,精确确定休瓦促矿床形成于83±1Ma,热林矿点形成于81.2±2.3Ma。同时通过刘兴旺等(2006)的辉钼矿Re-Os年龄(77±2Ma),并参考黄铁矿Re-Os测试结果(75±18Ma),可推断红山矿床主要形成发生于燕山晚期。根据上述定年结果,中甸弧成矿作用表现出一定的规律性:休瓦促→热林→红山,三矿床(点)具有成矿年代相近、空间等距、矿种由高温组合向低温组合变化、矿化类型相似、成矿母岩体就位深度递增等特点。这是同一构造-岩浆-成矿作用连续演化的结果。依据上述成矿规律,在中甸弧北部具有一定的找矿前景。

关键词： Re-Os 成矿年代成矿规律燕山晚期中甸弧

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序言

地质与勘探 2021年第4期57卷 I0001-I0001页

作者：卢映祥不详

战略性关键矿产是支撑节能环保、新一代信息技术、生物、高端装备制造、新材料、新能源、航空航天、尖端武器等新兴产业发展的重要原材料,既具有重大的经济意义,又对国家经济和安全至关重要,对世界经济和科技的发展具有重要战略意义。... 详细信息

战略性关键矿产是支撑节能环保、新一代信息技术、生物、高端装备制造、新材料、新能源、航空航天、尖端武器等新兴产业发展的重要原材料,既具有重大的经济意义,又对国家经济和安全至关重要,对世界经济和科技的发展具有重要战略意义。云南地处特提斯成矿域与环太平洋成矿域交汇部位,成矿条件优越,素有"有色金属王国"之称,形成了以关键矿产(如稀土、稀有、稀散和稀贵金属)为代表的特色成矿系统。

关键词：环太平洋新兴产业发展航空航天重要战略意义新一代信息技术关键矿产新能源高端装备制造