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Genesis and tectonic setting of Early Jurassic granitic rocks in Huashan Town,Xingcheng,western Liaoning
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作者 ZHAO Junfeng LI Weimin +1 位作者 LIU Tongjun GAO Jinhui 《Global Geology》 2024年第1期1-19,共19页
There are a large number of Mesozoic intrusive and volcanic rocks in western Liaoning of China,which is an ideal place to study the Mesozoic Paleo-Pacific subduction processes,and lithospheric destruc-tion of North Ch... There are a large number of Mesozoic intrusive and volcanic rocks in western Liaoning of China,which is an ideal place to study the Mesozoic Paleo-Pacific subduction processes,and lithospheric destruc-tion of North China Craton.Detailed petrographic,zircon U-Pb dating and geochemical studies of the Early Jurassic granites in Huashan pluton,Xingcheng,western Liaoning,indicate that the Early Jurassic granites were formed at 184-174 Ma,mainly composed of syenite and monzogranite.The geochemical characteristics show high contents of SiO_(2),Al_(2)O_(3)and Na_(2)O+K_(2)O,low contents of Fe_(2)O_(3)and MgO,enrichment in LREEs and LILEs,and depletion in HREEs and HFSEs,and have a high content of Sr and low contents of Y and Yb,with weak negative Eu anomalies and slightly negative anomalies of Ce,indicating that they are a set of intermediate-acidic adakitic granites in high-K calc-alkaline series.All the facts significantly suggest that the Early Jurassic adakitic granites were formed at the active continental margin in the context of Paleo-Pacific plate subduction. 展开更多
关键词 geochemistry PETROLOGY ADAKITE North China Craton western liaoning
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Geology and mineralization of the Hongqiling large magmatic nickel-copper-cobalt deposit(22×10^(4)t)in Jilin Province,China:A review
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作者 Cong Chen Yu-chao Gu +14 位作者 Di Zhang Tao-tao Wu Ai Li Yun-sheng Ren Qing-qing Shang Jian Zhang Xiong-fei Bian Fei Su Jia-lin Yang Qiu-shi Sun Xiao-hai Li Wan-zhen Liu Zhen-ming Sun Sen Zhang Yu-hui Feng 《China Geology》 CAS CSCD 2024年第4期762-796,共35页
The Hongqiling large nickel-copper-cobalt deposit(hereafter referred to as the Hongqiling deposit),a typical mafic-ultramafic copper-nickel deposit in China,boasts proven Ni(Ni)resources of approximately 22×10^(4... The Hongqiling large nickel-copper-cobalt deposit(hereafter referred to as the Hongqiling deposit),a typical mafic-ultramafic copper-nickel deposit in China,boasts proven Ni(Ni)resources of approximately 22×10^(4)t,associated copper resources of 2×10^(4)t,and associated cobalt(Co)resources of 0.5×10^(4)t,with Ni reserves ranking 10th among China's magmatic nickel deposits.Geotectonically,the Hongqiling deposit is situated in the superimposed zone between the Xing'an-Mongolian orogenic belt and the circum-Western Pacific's active continental margin belt.Its ore-bearing plutons occur within the metamorphic rocks of the Ordovician Hulan Group,with the emplacement of plutons and the locations of orebodies governed by the deep-seated Huifahe fault and its secondary NW-trending Fujia-Hejiagou-Beixinglong-Changsheng fault zone.In the deposit,the rock assemblages of ore-bearing plutons predominantly encompass gabbro-pyroxenite-olivine pyroxenite-pyroxene peridotite(pluton No.1)and norite-orthopyroxenite-harzburgite(pluton No.7),with ore-bearing lithofacies consisting primarily of olivine pyroxenite and pyroxenite facies.The Hongqiling deposit hosts stratoid,overhanging lentoid,veined,and pure-sulfide veined orebodies.Its ores principally contain metallic minerals including pyrrhotite,pentlandite,chalcopyrite,violarite,and pyrite.Despite unidentified magma sources of ore-bearing mafic-ultramafic rocks,it is roughly accepted that the magmatic evolution in the Hongqiling deposit primarily involved fractional crystallization and crustal contamination.The ore-forming materials were primarily derived from the upper mantle,mixed with minor crustal materials.The ore-bearing mafic-ultramafic rocks in the deposit,primarily emplaced during the Indosinian(208-239 Ma),were formed in an intense extension setting followed by the collisional orogeny between the North China Plate and the Songnen-Zhangguangcai Range Block during the Middle-Late Triassic.From the perspective of the metallogenic geological setting,surrounding rocks,ore-controlling structures,and rock assemblages,this study identified one favorable condition and seven significant indicators for prospecting for Hongqiling-type nickel deposits and developed a prospecting model of the Hongqiling deposit.These serve as valuable references for exploring similar nickel deposits in the region,as well as the deep parts and margins of the Hongqiling deposit. 展开更多
关键词 Nickel-copper-cobalt deposit Fractional crystallization Crustal contamination MAGMATIC MinERALIZATION Re-Os isotopic age Sulfur isotopic Metallogenic mode Prospecting model western Pacific’s active continental margin Mineral exploration engineering Hongqiling Jilin
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Analysis on the Satisfaction Degree of Agricultural Water Demand in Semiarid Area of Western Liaoning 被引量:1
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作者 张国林 梁群 宗英飞 《Meteorological and Environmental Research》 CAS 2010年第8期62-64,共3页
[Objective] The satisfaction degree of agricultural water demand was analyzed to provide climate basis for the agricultural structure adjustment and good harvest.[Method] By using integral humidity index and climatic ... [Objective] The satisfaction degree of agricultural water demand was analyzed to provide climate basis for the agricultural structure adjustment and good harvest.[Method] By using integral humidity index and climatic tendency rate,the satisfaction degree of water demand of crops and its trend variation were studied.[Result] The precipitation in the growing season of crops showed decrease trend in western Liaoning,and the climatic tendency rate was-8.660--18.560 mm/10 a,with the precipitation decrease of 43-93 mm in recent 50 years.The satisfaction degree of agricultural water demand was up to 72%-88% in average,and over 80% satisfaction degree accounted for 30%-60%,while water shortage probability reached 68%-90%.The satisfaction degree of Chaoyang,Lingyuan and Beipiao was the lowest,while that of Jianchang and Jiangping was relative higher.The satisfaction degree of gross agriculture water demand went down with the time,and climate tendency rate was up to-2.490%--3.863%/10 a,with the decrease of 12%-19% in recent 50 years.[Conclusion] With the reduction of precipitation,the satisfaction degree of water demand of crops went down,and the climate in western Liaoning became more and more dry. 展开更多
关键词 integral humidity index Tendency rate Growing season of crops Satisfaction degree western liaoning China
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Magma source and tectonic setting of the Dunde granite in the Western Tianshan:constraints from geochronology,geochemistry,and Sr–Nd–Hf isotopes
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作者 Zhaode Xia Haibo Ding Yanjiao Ru 《Acta Geochimica》 EI CAS CSCD 2023年第5期879-894,共16页
The Dunde iron-zinc polymetallic deposit is one of large iron deposits occurred in the Awulale Metallogenetic Belt,Western Tianshan(NW-China).This study reports new geochronology and geochemistry for granite in the Du... The Dunde iron-zinc polymetallic deposit is one of large iron deposits occurred in the Awulale Metallogenetic Belt,Western Tianshan(NW-China).This study reports new geochronology and geochemistry for granite in the Dunde mining area in order to constrain the tectonicmagmatic activities and metallogenesis of this region.Granites in the southwest of Dunde mining area are mainly syenogranites intruded into volcanics of the Dahalajunshan Formation in the Early Carboniferous,and they are far from the area where ore bodies and mineralized altered rocks are widely developed.LA-ICP-MS U–Pb zircon dating indicates that Dunde syenogranite was at 306.8±1.0 Ma,which could constrain the upper limit of metallogenic age for this deposit.The Dunde granites are high SiO_(2)(73.41–80.07 wt%),high differentiation index(D.I.=89.7–95.0),weakly peraluminous to metaluminous(A/CNK=0.94–1.08),and they are enriched in LILE and LREE and depleted in Eu,Ba,Sr and P_(2)O_(5),indicating that they belong to highly fractionated Ⅰ-type granite.Based on εHf values(+9.2 to+10.5)for zircon and high εNd(-t)values(+4.7 to+5.8)for whole-rock,and the two-stage model ages for 601–735 Ma,suggest that the magma source could be the juvenile lower crust.Combined with regional geological setting,the 306.8 Ma Dunde granites are formed in post-collision extensional tectonic setting. 展开更多
关键词 GRANITE GEOCHEMISTRY Magma source Tectonic setting Dunde deposit western Tianshan
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Survey and Countermeasures on Current Status of Farmer Training and Education Informatization in Western Liaoning Province
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作者 Zeguo DENG Jianwei LIU 《Asian Agricultural Research》 2023年第1期50-57,共8页
This study summarized the main achievements of farmers’training and rural informatization construction in the past few years,and explored the needs of rural informatization in western Liaoning Province.The current st... This study summarized the main achievements of farmers’training and rural informatization construction in the past few years,and explored the needs of rural informatization in western Liaoning Province.The current status of agricultural development in western Liaoning and farmers’needs for education and training and rural education informatization were surveyed.The construction of an education and technical support service platform for scientific and technological farmers in western Liaoning was proposed,aiming to use information technology to train modern professional farmers.Through independent and self-learning education and training methods,it is expected to promote great improvement in the scientific and technological quality and moral level of farmers in western Liaoning and cultivate professional farmers who are educated and understand both agricultural techniques and business management. 展开更多
关键词 western liaoning Province Professional farmers Education informatization TRAininG
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A New Troodontid (Theropoda: Troodontidae) from the Lower Cretaceous Yixian Formation of Western Liaoning, China 被引量:16
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作者 XUXing WANGXiaolin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第1期22-26,共5页
A specimen collected from the Lower Cretaceous Yixian Formation of western Liaoning, China, represents a new genus and species of troodontid theropod. The new taxon is named and described on the basis of the holotype ... A specimen collected from the Lower Cretaceous Yixian Formation of western Liaoning, China, represents a new genus and species of troodontid theropod. The new taxon is named and described on the basis of the holotype and the only known specimen, which comprises an articulated skeleton with the presacral vertebral, shoulder girdle and forelimbs missing as preserved. Diagnostic features of the new species include nasals that are sinusoid in lateral view, absence of a passage connecting the antorbital and maxillary fenestrae, relatively large teeth, plate-like chevrons forming a band along most of the length of the tail, and a long neck between the femoral head and shaft. The temporal constraints of the three paravian groups (Troodontidae, Dromaeosauridae and Aves) combined with the character distributions among the earliest known troodontids indicate a rapid evolution at the base of the Troodontidae. 展开更多
关键词 Early Cretaceous Yixian Formation Troodontidae western liaoning China
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A New Darwinopterid Pterosaur from the Middle Jurassic of Western Liaoning,Northeastern China and its Ecological Implications 被引量:13
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作者 Lu Junchang XU Li +1 位作者 CHANG Huali ZHANG Xingliao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2011年第3期507-514,共8页
A new species of Darwinopterus,D.robustodens sp.nov.is described and named.Based on the new specimen,the diagnostic characters of Darwinopterus are amended and include:rostral dentition composed of well-spaced,spike-... A new species of Darwinopterus,D.robustodens sp.nov.is described and named.Based on the new specimen,the diagnostic characters of Darwinopterus are amended and include:rostral dentition composed of well-spaced,spike-like teeth;the longest teeth are confined to the anterior half of the tooth row;tooth alveoli have raised margins;nasoantorbital fenestra confluent;inclined quadrate;elongate cervical vertebrae with low neural spine and reduced or absent ribs;long tail of more than 20 caudals partially enclosed by filiform extensions of the pre-and postzygapophyses;short metacarpus less than 60 per cent length of humerus,fifth toe with two elongate phalanges and curved second pedal phalanx of the fifth toe with the angle between the proximal and distal segments about 130 degrees.The complete specimen of the new pterosaur D.robustodens sp.nov.provides much more osteological information.The differences in tooth morphologies between Darwinopterus modularis and D.robustodens sp.nov.suggest that they filled different ecological niches.The hard integument-bearing Coleoptera may have been the main food source of Darwinopterus robustodens. 展开更多
关键词 Darwinopterus robustodens Tiaojinshan Formation Middle Jurassic western liaoning China
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M agmatic Gold Mineralization in the Western Qinling Orogenic Belt: Geology and Metallogenesis of the Baguamiao,Liba and Xiaogouli Gold Deposits 被引量:12
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作者 FENGJianzhong WANGDongbo +2 位作者 WANGXueming ZENGYishan LITiefeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第2期529-533,共5页
The superlarge Baguamiao, large Liba and Xiaogouli gold deposits represent three typical gold deposits different from the Carlin type in the western Qinling Orogenic Belt. Based on Ar-Ar dating of quartz from ores, U-... The superlarge Baguamiao, large Liba and Xiaogouli gold deposits represent three typical gold deposits different from the Carlin type in the western Qinling Orogenic Belt. Based on Ar-Ar dating of quartz from ores, U-Pb dating of single zircon from granite, tracing of H and O isotopes and studies on the mineralogy and texture of spots and bleached alteration developed in wall rocks, this paper focuses the relations between gold deposits and granite to clarify the origin of gold deposits and the metallogenesis in the tectonic evolution of the Qinling Orogenic Belt. The comprehensive studies show that the age of the granite (148.1-244 Ma) is identical with that of the gold deposits (131.91-232.56 Ma). It is suggested that the granite has close temporal, spatial and genetic relationship with the gold deposits. The granite provides a heat source, water source and considerable amount of ore-forming material. Finally, it is concluded that the orogeny by collision, emplacement of the granite and positioning of the gold deposits represent a successive process. Both the granite and gold deposits resulted from the syn-orogeny and post-orogeny tectonic evolution. 展开更多
关键词 western Qinling Orogenic Belt Baguamiao Gold deposit Liba Gold deposit Xiaogouli Gold deposit GRANITE
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Precious Fossil-Bearing Beds of the Lower Cretaceous Jiufotang Formation in Western Liaoning Province, China 被引量:10
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作者 ZHANG Lijun YANG Yajun ZHANG Lidong GUO Shengzhe WANG Wuli ZHENG Shaolin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2007年第3期357-364,共8页
Based on the subdivision into three members of the Lower Cretaceous Jiufotang Formation in western Liaoning, this paper deals mainly with the division and correlation of precious fossil birdand reptile-bearing beds of... Based on the subdivision into three members of the Lower Cretaceous Jiufotang Formation in western Liaoning, this paper deals mainly with the division and correlation of precious fossil birdand reptile-bearing beds of the formation in the Dachengzi, Chaoyang, Dapingfang.Meileyingzi and Fuxin-Yixian basins. Among them, the precious fossil-bearing beds in the Dachengzi Basin may be recognized as the Xidagou Bed of the second member and the Yangcaogoudonggou Bed of the third member; those in the Chaoyang Basin may be confirmed as the Shangheshou Bed of the second member and the Dongpochi Bed of the third member; those in the Dapingfang-Meileyingzi Basin are as the Lamagou Bed of the second member, the Huanghuagou Bed of the lower third member and the Yuanjiawa Bed of the upper third member; and those in the Fuxin-Yixian Basin are listed as the Tuanshanzi Bed of the second member and the Pijiagou Bed of the third member. Since these basins are distinctly separated and the bird and reptile fossils are mostly new genera and species, we have to use the associated fossil ostracod assemblages as index to correlate the Xidagou Bed with the Shangheshou Bed and the Lamagou Bed, and to correlate the Yuanjiawa Bed with the Yangcaogoudonggou Bed and the Pijiagou Bed. Primarily, we established the sequence of the precious fossil-bearing beds of the Jiufotang Formation in western Liaoning. They are represented by, in ascending order, the Xidagou Bed of the second member, the Huanghuagou Bed of the lower third member, and the Yuanjiawa Bed of the upper third member. Obviously, this work has significance for the study on the time-space distribution and radiation of birds and dinosaurs during the period of the middle Early Cretaceous. 展开更多
关键词 DIVISION correlation precious fossil-bearing beds Lower Cretaceous JiufotangFormation western liaoning
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Dongbeititan dongi,the First Sauropod Dinosaur from the Lower Cretaceous Jehol Group of Western Liaoning Province,China 被引量:11
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作者 WANG Xuri YOU Hailu +3 位作者 MENG Qingjin GAO Chunling CHENG Xiaodong LIU Jinyuan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2007年第6期911-916,共6页
We herein describe a partial postcranial skeleton of a sauropod dinosaur recovered from the Lower Cretaceous Jehol Group in the Beipiao area of western Liaoning Province, northeastern China. A suite of features it pos... We herein describe a partial postcranial skeleton of a sauropod dinosaur recovered from the Lower Cretaceous Jehol Group in the Beipiao area of western Liaoning Province, northeastern China. A suite of features it possesses, including the camellate internal structure of its presacral elements, the existence of pneumatocoels on the proximal ends of the dorsal ribs, and especially the medially deflected proximal portion of the femur, definitively establish the titanosauriform affinities of the specimen. It differs from other titanosauriforms in having a craniocaudally elongate coracoid with a squared cranioventral extreme and a long, smooth, and slightly convex acetabular edge of the pubis. It represents a new taxon, Dongbeititan dongi gen. et sp. nov. Comparative studies suggest that Dongbeititan is a basal titanosauriform, more derived than Euhelopus, Fusuisaurus, and Huanghetitan, but less derived than Gobititan and Jiutaisaurus. Dongbeititan represents the first sauropod dinosaur reported from the Lower Cretaceous Jehol Group of western Liaoning Province. 展开更多
关键词 DinOSAURIA SAUROPODA TITANOSAURIFORMES Jehol Group Yixian Formation Lower Cretaceous Beipiao western liaoning Province China
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Metallogenic Epoch and Ore-forming Environment of the Lamasu Skarn-porphyritic Cu-Zn deposit,western Tianshan,Xinjiang,NW China 被引量:22
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作者 ZHANG Zuoheng WANG Zhiliang +1 位作者 WANG Longsheng ZUO Guochao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第4期731-740,共10页
Granitic rocks, widely developed in the Lamasu copper ore region, western Tianshan were formed at 390.5±7.7 Ma according to the SHRIMP zircon U-Pb dating of the plagioclase granite porphyry. Based on the regional... Granitic rocks, widely developed in the Lamasu copper ore region, western Tianshan were formed at 390.5±7.7 Ma according to the SHRIMP zircon U-Pb dating of the plagioclase granite porphyry. Based on the regional tectonic evolution and published chronological data of both diagenesis and mineralization, the Biezhentao- Kokirqin region was rolled into the orogen associated with the closure of Yili Ocean during early Devonian. The N-S-trending thrust faults were formed during this period and accompanied by the intrusion of granitic rocks. On this stage, the paleo-Asian Ocean Plate entered into the early collision orogenic phase and the plagioclase granite porphyry intruded (390.5±7.7 Ma) and replaced with limestone of the Mesoproterozoic Kusongmuqieke Group, Jixianian System and formed the early phase of skarn-type copper mineralization in the Lamasu region. Furthermore, the subduction-melting of Bayingou Ocean Plate during Carboniferous generated a deep-seated magmatic chamber in the Lamasu copper ore region which located in the northwestern part of the Paleozoic Biezhentao-Kokirqin island arc. The magmatic chamber segregated Cu-bearing magmas, which transported upward to the shallow earth crust along the faults or fractures and formed the Cu-hosting porphyry. According to the research on the characteristics of the ore deposit and the ore-forming environment as mentioned above, the Lamasu Cu-Zn deposit was characterized by the superposing of mineralization at different geological settings and it was skarn-porphyritic type. 展开更多
关键词 Lamasu copper ore deposit diagenesis and mineralization ages western Tianshan
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An Adult Specimen of Hongshanosaurus houi (Dinosauria:Psittacosauridae) from the Lower Cretaceous of Western Liaoning Province, China 被引量:6
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作者 YOUHailu XUXing 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2005年第2期168-173,共6页
A new specimen consisting of a complete skull and lower jaw was discovered from the Lujiatun bed of the Lower Cretaceous Yixian Formation in the Lujiatun site, Beipiao, western Liaoning Province. It represents an adul... A new specimen consisting of a complete skull and lower jaw was discovered from the Lujiatun bed of the Lower Cretaceous Yixian Formation in the Lujiatun site, Beipiao, western Liaoning Province. It represents an adult specimen of Hongshanosaurus houi. Comparative studies show that Hongshanosaurus is distinguishable from its sister taxon Psittacosaurus by having the preorbital portion about half of the basal skull length, and the elliptical external naris, orbit, and a lower temporal fenestra oriented caudodorsally. 展开更多
关键词 DinOSAURIA Psittacosauridae Hongshanosaurus ONTOGENY Lower Cretaceous western liaoning
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Metallogenic Chronology of Boron Deposits in the Eastern Liaoning Paleoproterozoic Rift Zone 被引量:9
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作者 LUYuanfa CHENYuchuan +2 位作者 LIHuaqin XUEChunji CHENFuwen 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2005年第3期414-425,共12页
Lead isotopic analytic data of 30 ores gathered from the Zhuanmiao boron deposit, Wengquangou boron (iron) deposit and its Dongtaizi Ore Member constitute three isochrons, the corresponding ages of which are 1902 ... Lead isotopic analytic data of 30 ores gathered from the Zhuanmiao boron deposit, Wengquangou boron (iron) deposit and its Dongtaizi Ore Member constitute three isochrons, the corresponding ages of which are 1902 ± 12 Ma, 1852 ± 9 Ma and 1917 ± 48 Ma. Lead isotopic analyses of marble from the Xiquegou Member of the Qingchenzi orefield yield a Pb-Pb isochron age of 1844 ± 27 Ma. 40Ar-39Ar quick neutron activation dating of phlogopites and microclines coexisting with ore minerals in the Wengquangou boron (iron) and Zhuanmiao boron deposits shows that: (1) the phlogopite from the Wengquangou has a plateau age of 1923 ± 1.5 Ma and an isochron age of 1924 ± 2.5 Ma; (2) the microcline from the Wengquangou has the plateau age of 1407 ± 5.4 Ma and 220 ± 12 Ma and an isochron age of 1403 ± 19 Ma; (3) the phlogopites from the Zhuanmiao yield a plateau age 1918 ± 1.3 Ma and an isochron age of 1918 ± 2.9 Ma; (4) the microclines from the Zhuanmiao yield the plateau age of 1420 ± 16 Ma and 250 ± 8 Ma and an isochron age of 1425 ± 19 Ma and 269 ± 16 Ma. These ages indicate that the eastern Liaoning area happened around 1900 Ma, an important tectonomagmatic event, which is consistent with the worldwide Mid-Proterozoic tectonomagmatic event. During this period, the Proterozoic Liaohe Group was folded and underwent strong normal metamorphism, and the (hydrothermal) sedimentary boron deposits (or source beds) formed earlier were strongly superimposed by mineralization, resulting in enrichment of boron; later regional geological processes made little contribution to the formation of the boron deposits. Lead isotopic components show that the U-Pb and Th-Pb isotopic system reached homogenization in the ores whereas only the U-Pb isotopic system reached homogenization in the marble from the Xiquegou district, which indicates that the boron deposits superimposed in the studied area endured a relatively strong process of hydrothermal migmatization during the end phase of early Proterozoic metamorphism. 展开更多
关键词 boron deposits isotope chronology Pb-Pb isochron 40Ar-39Ar dating PALEOPROTEROZOIC eastern liaoning
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New Eoenantiornithid Bird from the Early Cretaceous Jiufotang Formation of Western Liaoning, China 被引量:8
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作者 LI Li DUAN Ye +3 位作者 HU Dongyu WANG Li CHENG Shaoli HOU Lianhai 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第1期38-41,共4页
Enantionithine birds are the most blooming branch of early birds and have distinct diversities. A large number of enantionithine birds have been reported from the Early Cretaceous Jiufotang Formation in western Liaoni... Enantionithine birds are the most blooming branch of early birds and have distinct diversities. A large number of enantionithine birds have been reported from the Early Cretaceous Jiufotang Formation in western Liaoning, China. Recently, we discovered a new eoenantiornithid bird from the Jiufotang Formation in Dapingfang Town, western Liaoning. A new eoenantiornithid bird, Dapingfangornis sentisorhinus gen. et sp. nov., is erected based on this complete skeleton with a skull. The new bird is distinguished from other known Mesozoic birds in a medium to small size, a distinct thorn-like process on the nasals, a sternum with a long and a short lateral processes. The thorn-like process on the nasal has not been discovered among known fossil birds, thus the discovery also provides new materials on the diversities of early birds. 展开更多
关键词 Eoenantiornithid Dapingfangornis sentisorhinus Jiufotang Formation Early Cretaceous western liaoning
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Largest Toothed Pterosaur Skull from the Early Cretaceous Yixian Formation of Western Liaoning, China, with Comments on the Family Boreopteridae 被引量:7
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作者 LU Junchang PU Hanyong +2 位作者 XU Li WU Yanhua WEI Xuefang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第2期287-293,共7页
A new pterosaur Moganopterus zhuiana gen. et sp. nov. is erected based on a complete skull with lower jaws and anterior cervical vertebrae. It is characterized by much elongated upper and lower jaws with at least 62 t... A new pterosaur Moganopterus zhuiana gen. et sp. nov. is erected based on a complete skull with lower jaws and anterior cervical vertebrae. It is characterized by much elongated upper and lower jaws with at least 62 total, long, curved teeth with sharp tips, a well developed parietal crest extending posterodorsally, forming an angle of 15 degrees with the ventral margin of the skull, the ratio of length to width of cervical vertebrae greater than 5:1. The skull length is 750 mm, and it is the largest toothed pterosaur found so far in the world. Based on this new pterosaur, the Boreopteridae can be divided into two subgroups: Boreopterinae sub-fam, nov. and Moganopterinae sub-fam, nov., which is also confirmed by the phylogenetic analysis. 展开更多
关键词 Moganopterus Boreopteridae Yixian Formation western liaoning
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Regional Metallogenesis of the Chang'an Gold Ore Deposit in Western Yunnan:Evidences from Fluid Inclusions and Stable Isotopes 被引量:10
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作者 CHEN Yue LIU Junlai +2 位作者 TRAN My Dung LI Yongchao BING Mingming 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2010年第6期1401-1414,共14页
The Chang'an gold ore deposit in western Yunnan is located at the southern segment of the Ailaoshan metallogenic belt.The ore bodies are preserved in fractured Ordovician sedimentary clastic rocks.The gold-bearing mi... The Chang'an gold ore deposit in western Yunnan is located at the southern segment of the Ailaoshan metallogenic belt.The ore bodies are preserved in fractured Ordovician sedimentary clastic rocks.The gold-bearing minerals occur dominantly in sulfide-quartz veins.Fluid inclusion analysis shows that the Chang'an gold ore deposit is characterized by epithermal gold mineralization at temperatures between 200℃and 280℃at a shallow crustal level.The mineralizing fluids have intermediate to low salinity(6%-18%) and low densities(0.72-1.27 g/cm^3).The ore minerals haveδ^(34)S in a range from -13‰to 3.57‰,concentrated from -2.06‰to 3.57‰with an average of 1.55‰.The ^(206)Pb/^(204)Pb,^(207)Pb/^(204)Pb and ^(208)Pb/^(204)Pb values are 18.9977-19.5748,15.7093-15.784,39.3814-40.2004 respectively.These isotope data suggest that the ore-forming elements were mainly derived from mixed crustal and mantle sources.The Chang'an gold ore deposit and Tongchang Cu-Mo deposit are closely related to each other in their spatial distribution and age of formation.They have similar sources of mineralizing elements and identical ore-forming metal elements,and show a close relationship in physical and chemical conditions of mineralization.The two deposits constitute an epithermal-porphyry -skarn type Cu-Mo-Au mineralization system in the Tongchang-Chang'an area,which is related to the Cenozoic high-K alkaline magmatism. 展开更多
关键词 indian-Eurasian continental collision Ailaoshan metallogenic belt high potassic alkaline magmatism epithermal gold deposit western Yunnan
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Fluid Inclusions of Orogenic Gold Deposits in the Zhongchuan Area,Western Qinling and Their Geological Significance 被引量:4
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作者 ZHANGZuoheng MAOJingwen 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第2期503-514,共12页
Orogenically-derived gold deposits of the Zhongchuan area in the western Qinling are distributed in the exo-contact thermal metamorphic zone. The country rocks hosting the deposits are predominantly of Devonian age wi... Orogenically-derived gold deposits of the Zhongchuan area in the western Qinling are distributed in the exo-contact thermal metamorphic zone. The country rocks hosting the deposits are predominantly of Devonian age with low-grade metamorphism and strong deformation with the ore deposits directly controlled by multi-level tectonic systems. Three types of inclusions from these deposits have been recognized: CO2-H2O, CO2-rich, and aqueous. The ore-forming fluids were mainly CO2-NaCl-H2O type characterized by rich CO2, low salinity, high temperature and immiscibility. Incorporated with earlier isotopic data, the regional geological setting and features of diagenesis and metallogeny, it can be concluded that the ore-forming fluids were derived from deep magma and mixed with meteoric and metamorphic water. The deposits formed during an intra-continent collisional orogeny, and some of the materials derived from the deep might have been involved in the ore-forming process. 展开更多
关键词 fluid inclusion orogenic gold deposit Zhongchuan area western Qinling
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Zircon SHRIMP U-Pb Dating of the Tourmalinites from Boron-bearing Series of Borate Deposits in Eastern Liaoning and its Geological Implications 被引量:5
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作者 LIU Jingdang XIAO Rongge +5 位作者 ZHANG Yanfei FAN Minghui WANG Shengzhi JIA Yuguo WANG Gang LIU Zhixue 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第1期118-130,共13页
This paper focused on the zircon sensitive high resolution ion micro-probeU-Pb geochronology of the tourmalinites from boron-bearing series of borate deposits in Eastern Liaoning. The zircons commonly have core-rim st... This paper focused on the zircon sensitive high resolution ion micro-probeU-Pb geochronology of the tourmalinites from boron-bearing series of borate deposits in Eastern Liaoning. The zircons commonly have core-rim structures, most cores show oscillatory zoning in cathodoluminescence and plane polarized light images, suggesting a magmatic detrital origin. Ages of the magmatic detrital zircons from the hyalotonrmalite samples (N13) and (N14) are 2175 ± 5 Ma and 2171 ± 9 Ma, respectively. Moreover, metamorphic zircon from the sample (N13) shows an age of 1906 ± 4 Ma. Zircon core and rim from the hyalotourmalite sample (N02) record ages of 2171 ± 6 Ma and 1889± 62 Ma, which are explained as indicating the formation and metamorphic ages. Combined with the geological and geochemical studies, it can be concluded that the tourmalinites are formed during sedimentary exhalative mineralizations in the mid-Paleoproterozoic (-170 Ma) and underwent the metamorphism in the late-Paleoproterozoic (-1900 Ma). The tourmalinites are the products of submarine acid volcanism in the extension rifting phase of the Liaoji Paleoproterozoic Rift, the rockforming materials of which are derived from the mantle sources with recycling crustal contamination. The emergence of tourmalinites not only indicates the mid-Paleoproterozoic tectonic-magmatic processes, but also provides impetus, heat and material sources for the mineralization of borate deposits in Eastern Liaoning. 展开更多
关键词 tourmalinites zircon sensitive high resolution ion micro-probe U-Pb dating boron deposits in Eastern liaoning mid-Paleoproterozoic
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Tectonic evolution and its control over deposition in fault basins: A case study of the Western Sag of the Cenozoic Liaohe Depression, eastern China 被引量:3
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作者 Zhang Zhen Bao Zhidong +2 位作者 Tong Hengmao Wang Yong Li Haowu 《Petroleum Science》 SCIE CAS CSCD 2013年第3期269-281,共13页
The main petroliferous basins in eastern China are Cenozoic fault basins, most of which have experienced two-stage tectonic evolution, i.e., rifting subsidence in the Paleogene and post-rifting thermal subsidence in t... The main petroliferous basins in eastern China are Cenozoic fault basins, most of which have experienced two-stage tectonic evolution, i.e., rifting subsidence in the Paleogene and post-rifting thermal subsidence in the Neogene-Quaternary. The episodic tectonic evolution and syndepositional faulting had significant influence on the fault basins in terms of accommodation space, deposition rate, and depositional facies zones. In this study, the tectonic deformation characteristics and the tectonic-depositional evolution of the Western Sag of the Cenozoic Liaohe Depression were investigated by comprehensive analysis of the available geological and geophysical data using the modern theory of tectonic geology and the balanced section technique. The tectonic deformation of the Cenozoic fault basin was characterized by superimposed faults and depression. In addition, there existed relatively independent but still related extensional tectonic systems and strike-slip tectonic systems. The tectonic evolution of the fault basin involved five stages, i.e., initial rifting stage (E2s4), intense faulting stage (E2s3), fault-depression transition stage (E3sl2), differential uplifting stage (E3d), and depression stage (N-Q). According to the characteristics of tectonic development and evolution of the Western Sag, the depositional evolution in the Cenozoic fault basin was divided into two stages, i.e., multi-episodic rifting filling in the Paleogene and post-rifting filling in the Neogene-Quaternary. The former rifting stage was further subdivided into four episodes with different characteristics of depositional development. The episodic faulting controlled the filling process and filling pattern of the Cenozoic Western Sag as well as the development and spatial distribution of associated depositional systems, whereas the syndepositional faults that developed in multiple stages in various tectonic positions controlled the development of depositional systems and sand bodies in the Western Sag. That is, the fault terraces on steep slopes controlled the development of sand bodies, the fault terraces on gentle slopes controlled the development of low-stand fan bodies, and the fault terraces or fault troughs in the central basin controlled the development of fluxoturbidite bodies. 展开更多
关键词 Fault basin syndepositional fault tectonic evolution depositional evolution western Sag
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A New Pterodactyloid Pterosaur from the Early Cretaceous of the Western Part of Liaoning Province, Northeastern China 被引量:2
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作者 LU Junchang LIU Cunyu +1 位作者 PAN Lijun SHEN Caizhi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第3期777-782,共6页
Pangupterus liui gen. et sp. nov. from the Jiufotang Formation of Sihedang, Lingyuan City, Liaoning Province is erected based on a nearly complete lower jaw. It is characterized by having a total of 36 slender curved ... Pangupterus liui gen. et sp. nov. from the Jiufotang Formation of Sihedang, Lingyuan City, Liaoning Province is erected based on a nearly complete lower jaw. It is characterized by having a total of 36 slender curved teeth with sharp tips, forming a distinct fish-grabbing mechanism; the teeth are well-spaced and are circular in section; the length ratio of the mandibular symphysis to the whole jaw is 20%; and the ratio of the tooth root width to tooth length is 12%. Toothed pterosaurs make up about 56.3% of the pterosaur assemblage from the Jiufotang Formation, which indicates that toothed forms played a key role in the ecosystem. 展开更多
关键词 PTEROSAURIA Pangupterus Jiufotang Formation western liaoning
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