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Origin of the Newly Discovered Zhunuo Porphyry Cu-Mo-Au Deposit in the Western Part of the Gangdese Porphyry Copper Belt in the Southern Tibetan Plateau,SW China

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Acta Geologica Sinica(English Edition) 2017年第1期91卷 109-134页

作者： HUANG Yong LI Guangming DING Jun DAI Jie YAN Guoqiang DONG Suiliang HUANG Hanxiao Chengdu center China Geological Survey tianjin center China Geological Survey

The newly discovered Zhunuo porphyry Cu-Mo-Au deposit is located in the western part of the Gangdese porphyry copper belt in southern Tibet, SW China. The granitoid plutons in the Zhunuo region are composed of quartz diorite porphyry, diorite porphyry, granodiorite porphyry, biotite monzogranite and quartz porphyry. The quartz diorite porphyry yielded zircon U-Pb ages of 51.9±0.7 Ma（Eocene） using LA-ICP-MS, whereas the diorite porphyry, granodiorite porphyry, biotite monzogranite and quartz porphyry yielded ages ranging from 16.2±0.2 to 14.0±0.2 Ma（Miocene）. CuMo-Au mineralization is mainly hosted in the Miocene granodiorite porphyry. Samples from all granitoid plutons have geochemical compositions consistent with high-K calc-alkaline series magmatism. The samples display highly fractionated light rare-earth element（REE） distributions and heavy REE distributions with weakly negative Eu anomalies on chondrite-normalized REE patterns. The trace element distributions exhibit positive anomalies for large-ion lithophile elements（Rb, K, U, Th and Pb） and negative anomalies for high-field-strength elements（Nb and Ti） relative to primitive mantlenormalized values. The Eocene quartz diorite porphyry yielded εNd（t） values ranging from-3.6 to-5.2,（-（87）Sr/-（86）Sr）i values in the range 0.7046–0.7063 and initial radiogenic Pb isotopic compositions with ranges of 18.599–18.657 -（206）Pb/-（204）Pb, 15.642–15.673 -（207）Pb/-（204）Pb and 38.956–39.199 -（208）Pb/-（204）Pb. In contrast, the Miocene granitoid plutons yielded ε（Nd）（t） values ranging from-6.1 to-7.3 and（87Sr/86Sr）i values in the range 0.7071–0.7078 with similar Pb isotopic compositions to the Eocene quart diorite. The Sr-Nd-Pb isotopic compositions of the rocks are consistent with formation from magma containing a component of remelted ancient crust. Zircon grains from the Eocene quartz diorite have ε（Hf）（t） values ranging from-5.2 to ＋0.9 and two-stage Hf model ages ranging from 1.07 to 1.46 Ga, while zircon grains from the M

关键词： Zircon U-Pb dating Sr-Nd-Pb-Hf isotope Zhunuo porphyry Cu-Mo-Au deposit Gangdese porphyry copper belt

Human-induced changes in recent sedimentation rates in Bohai Bay, China： Implications for coastal development

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Science China Earth Sciences 2018年第10期61卷 1510-1522页

作者： Fu WANG Lizhu TIAN Xingyu JIANG William MARSHALL Hong WANG tianjin center China Geological Survey (CGS) Tianjin 300170 China Key Laboratory of Muddy Coast Geo-Environment China Geological Survey Tianjin 300170 China Plymouth University Plymouth Devon PL4 8AA United Kingdom

In many countries, coastal planners strive to balance the demands between civil, commercial strategy and environmental conversation interests for future development, particularly given the sea level rise in the 21 st century. Achieving a sustainable balance is often a dilemma, especially in low-lying coastal areas where dams in inland river basin are trapping significant amounts of fluvial sediments. We recently investigated the shore of Bohai Bay in northern China where there has been a severe increase in sea level following a program of large-scale coastal reclamation and infrastructure development over the last five decades. To investigate this trend, we obtained sediment cores from near-shore in Bohai Bay, which were dated by ^(137)Cs and ^(210)Pb radionuclides to determine the sedimentation rates for the last 50 years. The average sedimentation rates of Bohai Bay exceeded 10 mm yr^(-1) before 1963, which was much higher than the rate of local sea-level rise. However, our results showed an overall decreasing sedimentation rate after 1963, which was not able to compensate for the increasing relative sea-level rise in that period. In addition, our results revealed that erosion occurred after the 1980 s in the shallow sea area of Bohai Bay. We suggest that this situation places the Bohai Bay coast at a greater risk of inundation and erosion within the next few decades than previously thought, especially in the large new reclamation area. This study may be a case study for many other shallow sea areas of the muddy coast if the sea level continues to rise rapidly and the sediment delivered by rivers continues to decrease.

关键词： 210^Pb, ^137Cs Sedimentation rate Reclamation Coast tianjin

A Newly Discovered Oil-bearing Mesoproterozoic Erathem within the Niu D1 Well, Liaoxi Depression, Yanliao Faulted Depression Zone, NE China

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Acta Geologica Sinica(English Edition) 2020年第1期94卷 202-203页

作者： SUN Qiushi GAO Xiaoyong ZONG Wenming SUN Shouliang ZHANG Tao XIAO Fei LI Yongfei SHI Lei Shenyang center of geological survey China Geological Survey(CGS)/Northeast China Center for Geoscience InnovationShenyang 110034China

Objective The Yanshan Fold Belt is located within the northern margin of the North China platform and contains welldeveloped and widespread Neoproterozoic and Mesoproterozoic sedimentary units with a total thickness of up to 9000 *** studies identified many oil seedlings as well as asphalt and ancient hydrocarbon reservoirs in Northern Hebei depression and western Liaoning *** research indicates that the Mesoproterozoic and Neoproterozoic sedimentary units are ideally suited for the formation of significant oil and gas *** Niu D1 well was drilled by the China geological survey(cgs)in the Niuyingzi area and intercepted oil immersions and oil-and gas-bearing units within a limestone reservoir in the middle Proterozoic Gaoyuzhuang Formation(Fig.1).This study presents new biomarker compound and carbon isotope data that indicate that the oil within this formation was derived from hydrocarbon source rocks of the Hongshuizhuang Formation,part of the Mesoproterozoic Jixian Series,and the reservoir type is overthrust fault fractured anticline hydrocarbon *** oil reservoir within the Gaoyuzhuang Formation limestone might represent the oldest oil reservoir discovered to date within the Yanliao faulted depression zone.

关键词： NE China A Newly Discovered Oil-bearing Mesoproterozoic Erathem within the Niu D1 Well Yanliao Faulted Depression Zone Liaoxi Depression

Advance in Matrix Effect Study of LA-MC-ICPMS U-Pb Dating on U-Bearing Oxide Minerals

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Acta Geologica Sinica(English Edition) 2018年第4期92卷 1680-1681页

作者： CUI Yurong TU Jiarun GENG Jianzhen YE Lijuan ZHOU Hongying LI Huimin tianjin center China Geological Survey

Objective With the development of analytic technologies, in-situ dating on U-bearing oxide minerals （e.g., cassiterite, rutile and baddeleyite） has been widely used in geological chronological researches and has attracted remarkable attention to explore evolution of the earth and obtain age information of various geological processes. Matrix effect related studies are especially important during in-situ U- Pb dating based on Laser Ablation Multiple Collector Inductively Coupled Plasma Mass Spectrometry （LA-MC- ICPMS）. However, to our knowledge, only few thorough and systematical matrix effect study of U-bearing oxide minerals has been reported. In this study, we systematically analyzed the matrix effect of U-bearing oxide minerals in order to take place the standards which are difficult to prepare with available standards.

关键词： ICPMS ID Pb Advance in Matrix Effect Study of LA-MC-ICPMS U-Pb Dating on U-Bearing Oxide Minerals MC

The Tectonic Implications of the Hongliuhe-Xichangjing Ophiolitic Mélanges Belt in the Central Region of the Beishan Orogen, NW China——Constrained by the U-Pb Ages of Detrital Zircons of the Metasandstones

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Acta Geologica Sinica(English Edition) 2020年第4期94卷 1256-1275页

作者： TIAN Jian XIN Houtian TENG Xuejian DUAN Xiaolong CHENG Xianyu ZHANG Yong REN Bangfang tianjin center China Geological SurveyTianjin 300170China

The tectonic attributes of different blocks within orogenic belts are of great significance for the study of accretionary processes and the evolution of Earth. The Hongliuhe-Niujianzi-Baiyunshan-Xichangjing ophiolitic mélange belt(HXOMB) is distributed in the heart of the Beishan Orogen, the Shuangyingshan and Minshui-Hanshan blocks being distributed in the south and north of the HXOMB respectively, and a large number of Early Paleozoic geological units are exposed on the blocks. According to the zircon age populations of the metasandstones in the Baiyunshan area recovered in this paper, when compared with the zircon age populations of the Paleozoic metasandstones reported in the Niujuanzi and Hanshan areas, we found that the metasandstones of the Shuangyingshan Block have age peaks at c. 598 Ma, 742 Ma, 828 Ma, 941 Ma, 990 Ma, 1168 Ma, 1636 Ma, 2497 Ma with non-significant age populations of 1500–1300 Ma, showing a possible affinity with the Tarim Craton;the metasandstones of the Minshui-Hanshan Block have age peaks at c. 606 Ma, 758 Ma, 914 Ma, 1102 Ma, 1194 Ma, 1304 Ma, 1672 Ma with significant age populations of 1500-1300 Ma, showing a possible affinity with the Chinese Central Tianshan Block. Therefore, the HXOMB of the Beishan Orogen is of great significance in plate segmentation, which separates the Tarim Craton in the south and the Chinese Central Tianshan Block in the north. Based on the evolutionary process of the Hongliuhe-Xichangjing ocean in the Beishan Orogen, we believe that break-up and convergence can be recognized as having occurred twice between the Chinese Central Tianshan Block and the Tarim Craton since the Mesoproterozoic in the Beishan area. This was related firstly to the break-up of the Columbia Supercontinent and the convergence of the Rodinia Supercontinent, mainly during the Middle Mesoproterozoic to Early Neoproterozoic, and secondly to the opening and closing of the Hongliuhe-Xichangjing ocean, mainly during the Early Paleozoic.

关键词： U-Pb ages of detrital zircons metasandstones Beishan Orogen Hongliuhe-Xichangjing ophiolitic mélanges belt Tarim Craton Chinese Central Tianshan Block

Mangrove wetlands distribution status identification, changing trend analyzation and carbon storage assessment of China

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China Geology 2024年第1期7卷 1-11页

作者： Chang Li Fu Wang Peng Yang Fei-cui Wang Yun-zhuang Hu Yan-lin Zhao Li-zhu Tian Rui-bin Zhao tianjin center(North China center of Geoscience Innovation) China Geological Survey(CGS)Tianjin 300170China Tangshan Hydrological survey and Research center of Heibei Province Tangshan063000China Key Laboratory of Coast Geo-Environment China Geological SurveyCGSTianjin 300170China tianjin Key Laboratory of Coast geological Processes and Environmental Safety Tianjin 300170China

This research investigates the ecological importance,changes,and status of mangrove wetlands along China’s *** interpretation,geological surveys,and ISO clustering unsupervised classification methods are employed to interpret mangrove distribution from remote sensing images from 2021,utilizing ArcGIS software ***,the carbon storage capacity of mangrove wetlands is quantified using the carbon storage module of InVEST *** show that the mangrove wetlands in China covered an area of 278.85 km2 in 2021,predominantly distributed in Hainan,Guangxi,Guangdong,Fujian,Zhejiang,Taiwan,Hong Kong,and *** total carbon storage is assessed at 2.11×10^(6) t,with specific regional data *** since the 1950s reveal periods of increase,decrease,sharp decrease,and slight-steady increases in mangrove areas in *** important finding is the predominant replacement of natural coastlines adjacent to mangrove wetlands by artificial ones,highlighting the need for creating suitable spaces for mangrove *** study is poised to guide future mangroverelated investigations and conservation strategies.

关键词： Mangrove Wetland Carbon storage Ecological conservation ArcGIS software platform Restoration InVEST model Quantitative analysis Coastal zone of China

Radiocarbon ages of different fractions of peat on coastal lowland of Bohai Bay: marine influence?

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Journal of Oceanology and Limnology 2018年第5期36卷 1562-1569页

作者： SHANG Zhiwen WANG Fu FANG Jing LI Jianfen CHEN Yongsheng JIANG Xingyu TIAN Lizhu WANG Hong tianjin Centre China Geological Survey（CGS）Tianjin 300170China Key Laboratory of Muddy Coast Geoenvironment CGSTianjin 300170China College of Urban and Environment Science Tianjin Normal UniversityTianjin 300387China

Peat in boreholes is the most important ^(14)C dating material used for constructing age framework. 20 bulk peat samples were collected from five boreholes, the ^(14)C ages of two fractions(organic sediment fraction and peat fraction) of the bulk peat samples were investigated by AMS-dating and which fraction is better to help construct an age framework for the boreholes were compared and discussed. The results indicated that the peat fraction give a good dating results sequence in the boreholes, compared with the corresponding organic sediment fraction. And the dating results of organic sediment fraction show 161-6 702 years older than corresponding peat fraction, which was caused by marine influence. Then, we suggest an experience formula as y =0.99 x-466.5 by the correlation analysis for correcting the marine influenced organic sediment ages within the conventional ages between 4 000 to 9 000 yrs BP, and more study should be carried out for the AMS ^(14)C dating of the bulk organic sediments.

关键词： coastal lowland of Bohai Bay peat fraction organic sediment fraction AMS ^14C dating marine influence

Assessment of geological Security and Integrated Assessment Geo-environmental Suitability in Worst-hit Areas in Wenchuan Quake

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Acta Geologica Sinica(English Edition) 2009年第4期83卷 816-825页

作者： LI Wenpeng WEN Dongguang ZHOU Aiguo SUN Xiaoming MENG Hui SHI Jusong CHEN Zongyu ZHANG Liqin FENG Xiaoming LIU Changli ZHOU Jianwei China Institute of Geo-Environmental Monitoring Beijing 100081 China geological survey Beijing 100037 Institute of Geomechanics China Academy of Geological Science Beijing 100081 tianjin geological survey center of cgs Tianjin 300170 Geomechanics Institute of Chinese geological Academy Beijing 100086 Nanjing geological survey center of cgs Nanjing 210016 The Institute of Hydrogeology and Environmental Geology CAGS Shi Jiazhuang 050061

The Wenchuan earthquake in 2008 and geo-hazards triggered by the earthquake caused large injuries and deaths as well as destructive damage for infrastructures like construction, traffic and electricity. It is urgent to select relatively secure areas for townships and cities constructed in high mountainous regions with high magnitude earthquakes. This paper presents the basic thoughts, evaluation indices and evaluation methods of geological security evaluation, water and land resources security demonstration and integrated assessments of geo-environmental suitability for reconstruction in alp and ravine with high magnitude earthquakes, which are applied in the worst-hit areas （12 counties）. The integrated assessment shows that：（1） located in the Longmenshan fault zone, the evaluated area is of poor regional crust stability, in which the unstable and second unstable areas account for 79% of the total; （2） the geo-hazards susceptibility is high in the evaluation area. The spots of geo-hazards triggered by earthquake are mainly distributed along the active fault zone with higher distribution in the moderate and high mountains area, in which the areas of high and moderate susceptibility zoning accounts for 40.1% of the total; （3） geological security is poor in the evaluated area, in which the area of the unsuitable construction occupies 73.1%, whereas in the suitable construction area, the areas of geological security, second security and insecurity zoning account for 8.3 %, 9.3% and 9.3 % of the evaluated area respectively; （4） geo-environmentai suitability is poor in the evaluated area, in which the areas of suitability and basic suitability zoning account for 3.5% and 7.3% of the whole evaluation area.

关键词： Wenchuan earthquake geological security carrying capacity of water and land resources geo-environmental suitability

Genesis of sandstone-type uranium deposits along the northern margin of the Ordos Basin,China

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Geoscience Frontiers 2020年第1期11卷 215-227页

作者： Ruoshi Jin Xueming Teng Xiaoguang Li Qinghong Si Wei Wang tianjin center China Geological SurveyTianjin 300170China Key Laboratory of Uranium Geology China Geological SurveyTianjin 300170China

Sandstone-type U mineral resources are among the important sources for nuclear *** U deposits in the Ordos Basin in China form part of the northern segment of the sandstone-hosted Central Asian Uranium *** types of mineralizations are recognized in this basin:"phreatic permeable type"and"interlayer permeable type",both exhibiting features equivalent to roll-front ***"interlayer permeable type"is widely accepted as the dominant mineralization type for sandstone-type uranium deposits within large-scale basins,also designated as the"interlayer oxidation zone type",based on the horizontal color zoning model representing changing redox *** we synthesize data from several drill holes within the Ordos Basin,which suggest that major Mesozoic tectonic movements controlled the evolution of the sedimentary system in the *** tectonic movements contributed to the formation of three angular unconformities and four parallel unconformities as inferred from the stratigraphic *** addition,other features such as vertical color zoning,paleo-channel controlled tabular or lentoid ore bodies(without roll-type)and a group interlayer horizontal zoning of altered minerals are also *** stratigraphic analysis indicates that the Ordos Basin generally witnessed four cycles of water level variations during *** the variations,three high water level and three low water level events were *** characteristics imply that the Ordos Basin went through multiple arid to humid climatic evolutions during *** the newly documented features with some novel concepts on the hydrodynamic mechanism for supergene ore-forming fluids,we propose a metallogenic model which invokes the importance of tectonic movements and water level fluctuations to explain the genesis of uranium deposits along the northern margin of the Ordos Basin.

关键词： Sequence stratigraphic analysis Hydrodynamic mechanisms Metallogenic model Tectonic history Ordos Basin