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Formation Age of the Sujiagou Komatiites in Western Shandong: Further Constraints from SHRIMP U-Pb Zircon Dating on Granitic Dykes

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Acta Geologica Sinica(English Edition) 2020年第4期94卷 877-883页

作者： WAN Yusheng dong chunyan XIE Hangqian WANG Shijin Beijing SHRIMP Center Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China Shandong Geological Survey Institute Jinan 250013China

Komatiites are presented as direct evidence for higher mantle temperatures during the Archean. In the North China Craton, komatiites with spinifex structure have been identified only at one locality, i.e. the Sujiagou area, western Shandong. They were considered as formed during the early Neoarchean mainly based on their association with supracrustal rocks considered to be that age. This study carried out SHRIMP U-Pb zircon dating on metamorphosed trondhjemitic and monzogranitic dykes intruding the Sujiagou komatiites, and they have magmatic zircon ages of 2592 ± 12 Ma and 2586 ± 13 Ma respectively. This provides direct evidence that the komatiites formed during the early Neoarchean.

关键词： granitic dyke SHRIMP U-Pb zircon dating Sujiagou komatiite Neoarchean western Shandong

Therapeutic cancer vaccines:advancements,challenges,and prospects

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Signal Transduction and Targeted Therapy 2024年第1期9卷 150-172页

作者： Ting Fan Mingna Zhang Jingxian Yang Zhounan Zhu Wanlu Cao chunyan dong Department of Oncology East Hospital Affiliated to Tongji UniversityTongji University School of MedicineShanghaiChina Postgraduate Training Base Shanghai East HospitalJinzhou Medical UniversityShanghai 200120China

With the development and regulatory approval of immune checkpoint inhibitors and adoptive cell therapies,cancer immunotherapy has undergone a profound transformation over the past ***,therapeutic cancer vaccines have shown promise by eliciting de novo T cell responses targeting tumor antigens,including tumor-associated antigens and tumor-specific *** objective was to amplify and diversify the intrinsic repertoire of tumor-specific T ***,the complete realization of these capabilities remains an ongoing ***,we provide an overview of the current landscape of cancer vaccines in this *** range of antigen selection,antigen delivery systems development the strategic nuances underlying effective antigen presentation have pioneered cancer vaccine ***,this review addresses the current status of clinical trials and discusses their strategies,focusing on tumor-specific immunogenicity and anti-tumor efficacy ***,current clinical attempts toward developing cancer vaccines have not yielded breakthrough clinical outcomes due to significant challenges,including tumor immune microenvironment suppression,optimal candidate identification,immune response evaluation,and vaccine manufacturing ***,the field is poised to overcome hurdles and improve patient outcomes in the future by acknowledging these clinical complexities and persistently striving to surmount inherent constraints.

关键词： breakthrough approval overcome

Archean Basement and a Paleoproterozoic Collision Orogen in the Huoqiu Area at the Southeastern Margin of North China Craton: Evidence from Sensitive High Resolution Ion Micro-Probe U-Pb Zircon Geochronology

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Acta Geologica Sinica(English Edition) 2010年第1期84卷 91-104页

作者： WAN Yusheng dong chunyan WANG Wei XIE Hangqiang LIU Dunyi Beijing SHRIMP Center Institute of Geology Chinese Academy of Geological Sciences Beijing 10037 China

This paper reports sensitive high resolution ion micro-probe U-Pb zircon ages for the ＂Huoqiu Group＂ and granitoids of the Early Precambrian basement in the Huoqiu area, southeastern margin of the North China Craton. The ＂Huoqiu Group＂ is similar in rock association and metamorphism to the khondalite series, apart from it containing considerable amounts of banded iron formation. All detrital zircons from the ＂Huoqiu Group＂ meta-sedimentary rocks are 3.0 Ga and 2.75 Ga, without any 2.5 Ga and younger ones, as is commonly found in Paleoproterozoic khondalite series in other areas of the North China Craton. In the Huoqiu area, 2.75 Ga and 2.56 Ga granitoids have also been identified. This basement assemblage underwent strong metamorphism during the late Paleoproterozoic （-1.84 Ga） tectonothermal event that is widely developed in the North China Craton. Thus the formation time of the ＂Huoqiu Group＂ can be constrained between 2.75 and 1.84 Ga in terms of detrital and metamorphic zircon ages. It is considered, combined with regional data, that there may be a Paleoproterozoic collision orogen extending in a NWW-SEE direction to the southern margin of the North China Craton.

关键词： khondalite series trondhjemite-tonalite-granodiorite sensitive high resolution ion micro-probe U-Pb dating Archean Paleoproterozoic collision orogen North China Craton

Geochemistry and SHRIMP U-Pb Zircon Dating of Mafic Rocks North of Zunhua City, Eastern Hebei, North China Craton： Paleoproterozoic Gabbro rather than Neoarchean Ophiolite

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Acta Geologica Sinica(English Edition) 2018年第3期92卷 1024-1040页

作者： XIE Hangqiang dong chunyan Alfred KRONER LIU Shoujie BAI Wenqian LIU Dunyi WAN Yusheng Beijing SHRIMP Center Institute of Geology Chinese Academy of Geological Sciences Beo'ing 10003 7 China Department of Geosciences University of Mainz D-55099 Mainz Germany

Abundant mafic-ultramafic blocks and dikes occur in the area north of Zunhua City, eastern Hebei Province, and were previously suggested to be part of a late Archean ophiolitic assemblage. We employed SHRIMP zircon dating and a geochemical study on these mafic and surrounding rocks to test the ophiolite hypothesis. The SHRIMP data suggest that three metagabbro samples were metamorphosed at ～1.8 Ga. Numerous ～2.5 Ga zircons display strong oscillatory zoning, characteristic of zircons from granitoid rocks but not from gabbro, so we suggest that these are xenocrystic grains. The age of these xenocrystic zircons and their metamorpbic rims suggests that these mafic blocks formed in Paleoproterozoic. The surrounding gneiss of intermediate composition also contains 2.5 Ga zircons with oscillatory zoning and 1.8 Ga metamorphic rims. Fractionated REE patterns and Nb, Ta, Zr, Hf negative anomalies to variable extent were observed in the mafic blocks and surrounding rocks, also supporting a significant difference in the chemistry of ophiolitic rocks. Our data suggest that many mafic blocks in northern Zunhua are not part of a late Archean ophiolite complex but part of a tectonically dismembered Paleoproterozoic intrusive gabbro complex. This study shows that late Paleoproterozoic metamorphism occurred in the western part of eastern Hebei Province.

关键词： metagabbro ophiolite SHRIMP zircon dating Zunhua North China Craton

Detrital zircon age model of Ordovician Wenquan quartzite south of Lungmuco-Shuanghu Suture in the Qiangtang area, Tibet: Constraint on tectonic affinity and source regions

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Science China Earth Sciences 2011年第7期54卷 1034-1042页

作者： dong chunyan LI Cai WAN YuSheng WANG Wei WU YanWang XIE HangQiang LIU DunYi Beijing SHRIMP Center oflnstitute of Geology Chinese Academy of Geological Sciences Beijing 100037 China College of Earth Sciences Jilin University Changchun 130061 China

Early to Middle Ordovician strata, including Wenquan quartzite, occur widely in the Himalaya, Lhasa, and south Qiangtang blocks. The Wenquan quartzite occurs on the south side of the Lungmuco-Shuanghu Suture in the Qiangtang area, Tibet. A total of 145 analyses on detrital zircons from the quartzite show five age ranges of 520-700, ca. 800, 900-1100, 1800-1900, and 2400-2500 Ma, with particularly distinct age peaks of 625 and 950 Ma. The reliable youngest detrital zircon age is 525 Ma, and the oldest, 3180 Ma. Detrital zircons show large variations in Hf isotope composition, with depleted mantle model ages t DM (Hf) ranging from 750 to 3786 Ma. Based on data obtained in this study and by others, the main conclusions are as follows: 1) Low-grade metamorphic sedimentary rocks are distributed extensively in the south of the Lungmuco-Shuanghu Suture and are Phanerozoic in age; 2) Pan-African and Grenville-Jinning tectono-thermal events were well developed in the source region of the Wenquan quartzite; 3) the source region shows crustal addition and recycling of different periods; 4) Wenquan quartzite was derived from the Gondwana metamorphic basement, suggesting that the Qiangtang block is a Gondwanan fragment.

关键词： Gondwana Tibetan Plateau detrital zircon SHRIMP dating Hf isotope Pan-African movement Grenville-Jinningmovement

U-Th-Pb behavior of zircons under high-grade metamorphic conditions:A case study of zircon dating of meta-diorite near Qixia,eastern Shandong

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Geoscience Frontiers 2011年第2期2卷 137-146页

作者： Yusheng Wan Dunyi Liu chunyan dong Shoujie Liu Shijin Wang Beijing SHRIMP Center Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China Shandong Geological Survey Jinan 250013 China

This paper carried out a study on U--Th--Pb behavior of zircons in a ＂dry＂ rock system during high-grade metamorphism in the Archean basement of eastern Sbandong. The studied sample has a mineral assemblage of plagioclase ＋ K-feldspar ＋ clinopyroxene ＋ biotite ＋ quartz and its pro- tolith is considered to be diorite. The zircons are stubby, equant or irregular in shape and show fir-leaf, sectorial, banded or oscillatory zoning. They contain inclusions, including mineral assemblages of clinopyroxene ＋ orthopyroxene ＋ hornblende ＋ quartz and plagioclase ＋ K-feldspar ＋ biotite ＋ quartz. Fifty SHRIMP analyses were performed on 34 zircon grains, which commonly yielded high Th/U ratios （mostly 〉0.5）. Most analyses are distributed along concordia from 2.54 to 2.25 Ga, with the youngest age being - 1.95 Ga. Compositions and ages show large variations even in a same zircon grain. Combined with early studies, conclusions can be drawn as follows： 1） the diorite underwent two episodes of high-grade metamorphism, at the end of the Neoarchean and the Paleoproterozoic （-2.50 Ga and 1.95 Ga or slightly later）; 2） high-grade metamorphism in a ＂dry＂ rock system may partially reset the U--Th--Pb system of zircons and, in this case, the ages between the oldest and youngest are chronologically meaningless; and 3） high Th/U ratios may be common features of zircons formed during high-grade metamorphic conditions.

关键词： Zirco/Is,U-Th--Pb systemReset High-grademetamorphism SHRIMP dating Early Precambrian

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Heavenly Lake

China Today 2016年第1期65卷 64-67页

作者： dong chunyan 不详

TIANCHI(Heavenly Lake)is in Fukang City,Changji Hui Autonomous Prefecture,just 68 kilometers from Urumqi,capital city of Xinjiang Uygur Autonomous *** 548-square-kilometer Tianchi Scenic Zone is divided into eight areas,consisting of the lake itself and the mountains and valleys surrounding *** have ready access to highways and telecommunication networks.

关键词： Heavenly Lake

Palaeoproterozoic Khondalite Belt in the western North China Craton: New evidence from SHRIMP dating and Hf isotope composition of zircons from metamorphic rocks in the Bayan Ul-Helan Mountains area

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Chinese Science Bulletin 2007年第21期52卷 2984-2994页

作者： dong chunyan LIU DunYi LI JunJian WAN YuSheng ZHOU HongYing LI Chengdong YANG YueHeng XIE LieWen Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China Beijing SHRIMP Center Beijing 100037 China Tianjin Institute of Geology and Mineral Resources China Geological Survey Tianjin 300170 China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

Zircom U-Pb age and Hf isotope analyses were made on gneissic granite and garnet-mica two-feldspar gneiss from the Helanshan Group in the Bayan Ul-Helan Mountains area, the western block of the North China Craton (NCC). Zircons from the gneissic granite commonly show core-mantle-rim structures, with magmatic core, metamorphic mantle and rim having ages of 2323±20 Ma, 1923±28 Ma and 1856±12 Ma, respectively. The core, mantle and rim show similar Hf isotope compositions, with single-stage depleted mantle model ages (TDM1) of 2455 to 2655 Ma (19 analyses). Most of the detrital zircons from the garnet-mica two-feldspar paragneiss have a concentrated U-Pb age distribution, with a weighted mean 207Pb/206Pb age of 1978±17 Ma. A few detrital zircons are older (2871 to 2469 Ma). The age for metamorphic overgrown rim was not determined because of strong Pb loss due to their high U content. The zircons show large variation in Hf isotope composition, with TDM1 ages of 1999 to 3047 Ma. In com- bination with previous studies, the main conclusions are as follows: (1) protolith of the khondalite se- ries in the Helanshan Group formed during Palaeoproterozoic rather than the Archaean as previously considered; (2) The results lend support to the contention that there is a huge Palaeoproterozoic Khondalite (metasedimentary) Belt between the Yinshan Mountains Block and the Ordos Block in the Western Block of NCC; (3) The widely-distributed bodies of early Palaeoproterozoic orthogneisses in the Khondalite Belt might be one of the important sources for detritus material in the khondalite series; (4) Collision between the Yinshan Block, the Ordos Block and the Eastern Block occurred in the same tectonothermal event of late Palaeoproterozoic, resulting in the final assembly of the NCC.

关键词：孔兹岩带古元古生代年代测定贺兰山

Eastern Ancient Terrane of the North China Craton

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Acta Geologica Sinica(English Edition) 2016年第4期90卷 1082-1096页

作者： WAN Yusheng LIU Shoujie Alfred KRONER dong chunyan XIE Hangqiang XIE Shiwen BAI Wenqian REN Peng MA Mingzhu LIU Dunyi Beijing SHRIMP Center Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China Department of Geosciences University of Mainz D-55099 Mainz Germany

Based on the spatial distribution of ancient rocks and zircons, three ancient terranes older than ca. 2.6 Ga have recently been identified in the North China Craton, namely the Eastern, Southern, and Central Ancient Terranes. The Eastern Ancient Terrane is the best studied and understood of the three ancient terranes. It has a long geological history back to ca. 3.8 Ga ago and includes the areas of Anshan-Benxi, eastern Hebei, eastern Shandong and western Shandong. In Anshan-Benxi, several different types of 3.8 Ga rocks were discovered together with 3.1-3.7 Ga rocks, whereas 2.9-3.0 Ga K-rich granites and 2.5 Ga syenogranite occur on larger scales. In eastern Hebei, 3.0-3.4 Ga rocks and older detrital and xenocrystic zircons were identified. In eastern Shandong, there are a large volumes of 2.7 Ga and 2.9 Ga rocks. In western Shandong, early Neoarchean （2.6-2.7 Ga） intrusive and supracrustal rocks are widely distributed. Whole-rock Nd and zircon Hf isotope data suggest that both mantle additions and crustal recycling played important roles within the Eastern Ancient Terrane during almost every tectono-magmatic event. Most BIFs in the North China Craton are late Neoarchean in age and are distributed on continental crust along the western margin of the Eastern Ancient Terrane, probably suggesting that a stable environment was one of the key factors for the formation of large-scale BIFs.

关键词： Zircon age Hf isotopes Archean Eastern Ancient Terrane North China Craton