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Post-Orogenic Granites in Pingwu Region, Northwest sichuan: Evidence for North china Block and Yangtze Block Collision during Triassic

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Journal of china University of Geosciences 2009年第2期20卷 250-273页

作者：裴先治李佐臣丁仨平冯建赟李瑞保孙雨张亚峰刘战庆 state key laboratory of Continental Dynamics Northwest University key laboratory of western china’s mineral resources and geological engineering of Ministry of Education Chang’an University key laboratory of western china's mineral resources and geological engineering of the Ministry of Education College of Earth Science and Land ResourcesChang'an University key laboratory of western china’s mineral resources and geological engineering of the Ministry of Education College of Earth Science and Land ResourcesChang’an University

The Nanyili （南一里）, Laohegou （老河沟）, and shaiziyan （筛子岩） granitic intrusions are located in the southern margin of the Bikou （碧口） block in Pingwu （平武） area, Northwest sichuan （四川）. The petrography and geochemical characteristics of the granitic intrusions as well as their source and tectonic settings are reported and discussed in this article. The Laohegou and shaiziyan granites are with high siO2 （69.89 wt.%-73.05 wt.%） and Al2O3 contents, and A/CNK=1.04-1.12. They are typical strongly peraluminous granites, with supersaturation in AI and si. The abundance of ∑REE varies in the range of （33.13-89.12）×10^-6. The rocks show an LREE enrichment pattern and obvious Eu negative anomaly. The trace element geochemistry is characterized evidently by a negative anomaly of Ta, Nb, Ti, etc. and a positive anomaly of Rb, Ba, sr, etc.. Zircons of the Nanyili granite have higher Th/U ratios, and their CL images have internal oscillatory zoning, suggesting that the zircons of the samples are igneous in origin. The LA ICP-Ms zircon U-Pb isotopic concordia diagram yields an age of 223.1±2.6 Ma （MsWD=1.4）, which indicates that the granodiorite intrusions formed in the early Late Triassic. The Nanyili, Laohegou, and shaiziyan granites have the characteristics of post-collisional granites and are regarded as post-orogenic granites. Thus, the granite intrusions are interpreted as syn-collisional granites that resulted from the crustal thickening caused by the collisions between the North china plate and the Yangtze plate during the Indosinian. The granitic intrusions formed in a transitional environment from syn- （compressional environment） to post-collision （extensional environment）.

关键词： strongly peraluminous granite LA ICP-Ms dating geochemistry tectonic setting post-collision Bikou block.

A Preliminary Review of Metallogenic Regularity of Tin Deposits in china

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Acta Geologica sinica(English Edition) 2015年第3期89卷 1021-1035页

作者： CHEN Zhenghui sHENG Jifu LIU Lijun WANG Denghong LIANG Ting WANG Chenghui key laboratory of Metallogeny and mineral Resource Assessment Institute of Mineral ResourcesChinese Academy of Geological Sciences china University of Geosciences key laboratory of western china's mineral resources and geological engineering Ministry of EducationEarth Science and Resources College of Chang'an University

china is rich in tin resources,and contains many types of tin *** the tin deposit types,the cassiterite-sulfide type,skarn type and quartz vein type occupy a large proportion of tin resources and *** the aspect of exploitation and utilization,the most important types are cassiterite-sulfide type and quartz vein *** cassiterite-sulfide type tin deposits are mainly located in Northern Guangxi and Eastern Yunnan,skarn type deposits are mainly distributed in the ore-concentration areas of south Hunan in Middle Nanling,and the quartz vein type tin deposits are mainly distributed in south china,such as western Fujian,Middle Jiangxi,Northern Guangzhou and southern *** most important metallogenic epoch for tin deposits is the Mesozoic *** metallogenic geotectonic background is mainly continental environments after orogeny process,with strong tectonic changes,interlaced deep fracture and frequent *** the most distinctive feature is the well developed Mesozoic granites,which have a close relationship with tin *** on the detailed study of the data from 873 tin deposits in china,this paper summarized the metallogenic regularity of tin deposits,classified 20 important metallogenic series of tin or tin-associated deposits,and inferred that the cassiterite-sulfide type,skarn type,quartz vein type and greisen type are the main prediction types of tin ***-four tin-mineralization belts were divided,among which,19 belts are the most *** addition,a series of maps about tin metallogenic belts and tin metallogenic regularity were compiled,aiming to provide theoretical basis for potential estimation and prediction of tin mineral resources.

关键词： tin deposits type of tin deposits mineralization epoch tin metallogenic belt metallogenicregularity

The LA-ICP-Ms zircons U-Pb ages and geochemistry of the Baihua basic igneous complexes in Tianshui area of West Qinling

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science china Earth sciences 2007年第z2期50卷 264-276页

作者： PEI XianZhi DING saPing ZHANG GuoWei LIU HuiBin LI ZuoChen LI GaoYang LIU ZhanQing MENG Yong key laboratory of western china's mineral resources and geological engineering Ministry of Education Faculty of Earth science and Land resources Chang'an University Xi'an 710054 China Key Laboratory of Western China's Mineral Resources and Geological Engineering Ministry of Education Faculty of Earth science and Land resources Chang'an University Xi'an 710054 China State Key Laboratory of Continental Dynamics Department of Geology Northwest University Xi'an 710069 China Key Laboratory of Western China's Mineral Resources and Geological Engineering Ministry of Education Faculty of Earth science and Land resources Chang'an University Xi'an 710054 China

Baihua meta-igneous complex consists mainly of pyroxenite-gabbro(diorite)-diorite-quartz diorite. They form a complete comagmatic evolutionary series. The geochemical characteristics of basic-interme- diate basic igneous rocks indicate that they belong to a tholeiite suite. The REE distribution pattern is nearly flat type and LREE is slightly enriched type, and their primitive mantle-normalized and MORB-normalized trace element spider diagrams are generally similar; the LIL elements (LILE) Cs, Ba, sr, Th and U are enriched, but Rb, K and the HFsEs Nb, P, Zr, sm, Ti and Y are relatively depleted. All these show comagmatic evolution and origin characteristics. The tectonics environment discrimination of trace element reveals that these igneous complexes formed in an island-arc setting. The LA-ICP-Ms single-zircons U-Pb age of Baihua basic igneous complex is 434.6±1.5 Ma (MsWD = 1.3), which proves that the formation time of the island-arc type magmatite in the northern zone of West Qinling is Late Ordovician or Early silurian, also reveals that the timing of subduction of paleo-ocean basin represented by the Guanzizhen ophiolite and resulting island-arc-type magmatic activities is probably Middle-Late Ordovician to Early silurian.

关键词： basic igneous complex, island-arc setting, LA-ICP-Ms, zircons U-Pb isotopic ages, Tianshui area, West Qinling

U–Pb Zircon Geochronology and Geochemistry of the Neoproterozoic Liujiaping Group Volcanics in the Northwest Margin of the Yangtze Block:Implications For the Breakup of the Rodinia supercontinent

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Acta Geologica sinica(English Edition) 2015年第4期89卷 1213-1225页

作者： LI Zuochen PEI Xianzhi LI Ruibao PEI Lei LIU Chengjun CHEN Youxin XU Tong YANG Jie WEI Bo key laboratory of western china's mineral resources and geological engineering Ministry of EducationFaculty of Earth Science and ResourcesChang'an University Faculty of Earth science and mineral resources China University of Geosciences

Investigation of the petrogenesis and the origin of zircons from the volcanic rocks of the Liujiaping Group of the back-Longmenshan tectonic belt in the northwest margin of the Yangtze Block is conducted by analysis of U-Pb geochronology and geochemistry. Results show that selected zircons are characterized by internal oscillatory zonings and high Th/U ratios （0.43-1.18）, indicating an igneous origin. Geochronological results of LA-ICP-Ms U-Pb dating of the Liujiaping Group zircons yield an age of 809 - 11 Ma （MsWD = 2.2）, implying that the volcanic rocks were formed in the Late Neoproterozoic. Geochemical analysis shows that the rocks are calc-alkaline, supersaturated in AI, and metaluminous to weakly peraluminous. Rare-earth elements are present at high concentrations （96.04-265.48 ppm） and show a rightward incline and a moderately negative Eu anomaly, similar to that of continental rift rhyolite. Trace element geochemistry is characterized by evident negative anomalies of Nb, Ta, P, Th, Ti, inter alia, and strong negative anomalies of K, Rb, sr, et al. We conclude that the Liujiaping Group volcanic rocks resulted from typical continental crust source petrogenesis and were formed in a continental margin setting, which had no relation to subduction, and thus, were the products of partial melting of the lower crust due to crustal thickening caused by active continental margin subduetion and arc-continent collision orogeny in the northwestern Yangtze Block and were triggered by the breakup of the Rodinia supercontinent during the Neoproterozoic.

关键词： geochemistry zircon LA-ICP-Ms U-Pb age late Precambrian tectonics shaanxiprovince

Petrogenesis of the Xuanwoling mafic–ultramafic intrusion in the northeastern Tarim Block(Northwest china)

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Chinese Journal Of Geochemistry 2015年第1期34卷 69-84页

作者： Zhao-De Xia Chang-Yi Jiang Ming-Zhe Xia school of Earth science and resources Chang’an University Jiang key laboratory of western china’s mineral resources and geological engineering of Ministry of Education Chang’an University

Beishan Terrane, located in the northeast of the Tarim Block, in northwest china, has developed a 500-km long and 100-km wide belt of Permian mafic–ultramafic intrusions One of these mafic–ultramafic intrusions, the Xuanwoling Intrusion, is composed of dunite, troctolite, olivine gabbros and gabbros, with cumulate texture and rhythmic layering The crystallization sequence is olivine ? spinel ? plagio clase ? pyroxene, indicating that the crystallization pressure is lower than 0.5–0.8 GPa and that the intrusion has undergone variable degrees of crustal contamination, increasing from dunite to gabbros. The olivines found in the Xuanwoling Intrusion have high Fo values(up to 90), suggesting a primary magma with a high composition of mg. It is likely that this high-mg magma was produced at extremely high temperatures(1,330–1,350 °C), and as a result, Nd–sr isotopic compositions similar to oceanic island basalts are found in the Xuanwoling Intrusion, which we propose arose from the mantle plume.

关键词：中国西北地区超镁铁质东北部塔里木盆地侵入 Nd-sr同位素成因纯橄榄岩

Advances in ethnopharmacology,phytochemistry and pharmacology of Erigerontis Herba and its Chinese medicine prescriptions

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Traditional Medicine Research 2025年第1期10卷 44-61页

作者： Yang Zhou Yuan-Yan Huang Ding-Yue shang Ying Chen Meng Tian Cheng-Yu Jin Xin Lu Bing-Chun Yan Han-Qing Pang Institute of Translational Medicine School of MedicineYangzhou UniversityYangzhou 225009China Jiangsu key laboratory of Integrated Traditional Chinese and western Medicine for Prevention and Treatment of senile Diseases Yangzhou UniversityYangzhou 225009China school of Medicine Nanjing University of Chinese MedicineNanjing 210023China state key laboratory for Chemistry and Molecular engineering of Medicinal resources Guangxi Normal UniversityGuiling 541004China.

Erigerontis Herba(EH),the dried whole plant of Erigeron breviscapus,is well-known for circulating blood,activating meridians to alleviate pain,expelling wind,and clearing away *** has been extensively utilized in southern china for the treatment of stroke hemiplegia,chest stuffiness and pains,rheumatic arthralgia,headache,and *** review focuses on the botany,ethnopharmacology,phytochemistry,pharmacology and toxicity of EH and its related prescriptions to offer new insights for prospective research of *** information about EH was retrieved from ancient records and books,PubMed,china National Knowledge Infrastructure,Chinese Pharmacopoeia,Web of science,Doctoral and Master’s Theses,and various electronic *** is a member of Compositae family and is mainly grown in southern *** Chinese medicine records that EH has the effects of circulating blood and removing blood stasis,expelling wind,and removing cold,as well as relieving rigidity of muscle and relieving *** now,nearly 200 ingredients have been characterized from EH,including flavonoids,caffeoyls,aromatic acids,coumarins,pentacyclic terpenoids,volatile oil and other *** extracts,EH related prescriptions(Dengzhan Xixin injection,Dengzhan shengmai capsules,etc.)or compounds(scutellarin,scutellarein,etc.)possessed obvious therapeutic effects of ischemic stroke,cerebral hemorrhage,myocardial infarction,Alzheimer’s disease,diabetes and its complications,gastric cancer,bone,and joint degenerative ***,the major active compound of EH,has been used as a quality *** no obvious toxicity of EH has been *** to its traditional applications,ethnopharmacology,phytochemistry,pharmacology,and toxicity,EH was applied as a valuable herb for clinical application in food and medicine *** several compounds have been shown to possess diverse biological activities,the underlying mechanisms of their actions remain *** fully exploi

关键词： Erigeron breviscapus traditional applications ethnopharmacology phytochemistry pharmacology

Microstructure evolution of loess under multiple collapsibility based on nuclear magnetic resonance and scanning electron microscopy

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Journal of Mountain science 2021年第10期18卷 2612-2625页

作者： WANG Hai-man NI Wan-kui YUAN Kang-ze LI Lan NIE Yong-peng GUO Ye-xia College of geological engineering and Geomatics Chang’an UniversityXi'an 710054China key laboratory of western china's mineral resources and geological engineering Ministry of EducationChang’an UniversityXi'an 710054China

In recent years, the acceleration of urbanization in loess areas has prompted frequent dismantling and reconstruction of old urban areas. Demolition and reconstruction of buildings involve multiple collapses of the foundation. To study microstructure evolution of loess under multiple collapsibility, this paper selects undisturbed loess samples from Guyuan, Northwest china for multiple compression tests. Using nuclear magnetic resonance(NMR) imaging and scanning electron microscopy(sEM) as auxiliary methods, a combination of qualitative and quantitative analyses was used to study the microstructure of loess samples before and after various number of collapses under different pressures. Results show that the loess does undergo multiple collapse under 200 kPa pressure. Pore is an important reason for loess collapse. The initial collapse comes primarily from the compression of macropores and mesopores, and the second collapse comes primarily from mesopore compression. The compression process of loess can be roughly divided into two stages. First, under the action of dissolution and compression, the relative displacement of soil particles occurs. Macropores and mesopores are destroyed first, generating small pores. second, with increasing pressure and times of collapses, pore compression gradually transforms into small pore compression. During the first collapse, particle aggregates disintegrate due to water and pressure. However, with increasing times of collapses, the contact relationship between particles gradually changes from the point contact to face contact. Loess particles tend to gradually become rounded. The study of the microstructure provides the possibility to further reveal the mechanism of multiple collapsibility of loess.

关键词： Loess Multiple collapse Microstructure Nuclear magnetic resonance Pore volume

Geochronological and Geochemical Constrains on Petrogenesis of the Jietebutiao A-type Granite in West Junggar,Xinjiang

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Acta Geologica sinica(English Edition) 2013年第1期87卷 131-147页

作者： YANG Gaoxue LI Yongjun TONG Lili ZHANG Bing TIAN Zhixian YANG Baokai Ministry of Education Key Laboratory of Western China's Mineral Resources and Geological EngineeringSchool of Earth Science and ResourcesChang'an University Number 7 geological Brigade Xinjiang Bureau of Geology and Mineral Resource Exploration

Late Paleozoic post-collisional granitoids are widespread in West Junggar, as well as northern Xinjiang. As a representative of those intrusions, the Jietebutiao granite occurs in the southwestern margin of the West Junggar （northwest china）, and is mainly composed of mid-coarse- grained monzogranite and syenogranite. In the present study, we report the results of high-precision zircon laser-ablation-inductively-coupled plasma mass-spectrometry U-Pb dating on the Jietebutiao granite for the first time, and yield weighted mean 2~~pb/23sU ages of 287 ＋ 9 Ma and 278 ~ 3 Ma for monzogranite and syenogranite, respectively. The Jietebutiao granite has a pronounced A-type affinity; it is metaluminous to slightly peraluminous; has a high-K calc-alkaline composition; high concentrations of Na20 ＋ I（20, varying from 6.8 to 8.5 wt%; high FeOt/MgO; 10 000Ga/AI ratios, a low CaO, MgO, and TiO2 content; enriched in some large ion lithophile elements （LILE, such as Rb and Th） and high field strength elements （HFsE, such as Zr, Hf, and Y）; and depleted in sr, Ba, and Ti. In addition, the granite has a relatively high rare earth element （REE） content （except for Eu）, with significant negative Eu anomalies （Eu/Eu＊ = 0.01-0.72）, and showing slight tetrad REE patterns and non-charge and radius controlled （CHARAC） trace element behavior. Petrographic, geochemical, and geochronological data suggest that the parental magma of Jietebutiao intrusions are of mixed origin, and are most probably formed by the interaction between the lower crust- and mantle-derived magmas in the Early Permian post-collisional tectonic setting. The basaltic magmas underplated and interacted with the lower crust that was dominated by deeply buried arc （and back-arc basin） series and the oceanic crust formed in the Paleozoic, and then triggered the partial melting of the juvenile lower crust, producing voluminous granitic melts and forming the Jietebutiao A2-type monzogranites, with the lithospheric mantle progres

关键词： A-type granite geochronology petrogenesis post-collisional West Junggar

Noise Reduction for InsAR Phase Images Using BM3D

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Chinese Journal of Electronics 2014年第2期23卷 329-333页

作者： ZHANG Wenge ZHANG Qin ZHAO Chaoying YANG Chengsheng ZOU Weibao College of Geology engineering and Geomatics Chang'an University key laboratory of western china's mineral resources and geological engineering Ministry of Education Chang'an University

This paper extends the application of Block-matching(BM) and 3D transform-domain collaborative filtering(BM3D) to the noise reduction in Interferometric synthetic aperture radar(In sAR) phase imagery,and proposes a denoising algorithm which can effectively remove noise and preserve fringes. since the noise level estimated by a median estimator is not always optimal for proposed algorithm in wavelet domain, a method of calculating optimal noise standard deviation is also *** proposed algorithm is efficient and robust. Experimental results show that the visual quality and evaluation indexes of proposed algorithm outperform other filters for both simulated and real In sAR images.

关键词： Image processing Interferometric synthetic aperture radar(In sAR) Phase noise reduction Block-matching(BM) Wavelet transform