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Identification of the Original Tectonic Setting for Oceanic Andesite Using Discrimination Diagrams:An Approach Based on Global Geochemical Data Synthesis

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Journal of Earth Science 2022年第3期33卷 696-705页

作者： Xinyu Liu Qi zhang chengli zhang State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi'an 710069China Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China

Systematical analyses of data from GEOROC and PetDB database show that large amount of Cenozoic andesites occurred in the various oceanic environments such as mid-oceanic ridge,plumerelated island and oceanic *** this study,we employed the geochemical data of 351 mid-ocean ridge andesites(MORA),2539 plume-related andesites(PRA)and 3488 oceanic arc andesites(OAA)from the database to discuss the relationship between andesite tectonic settings and their geochemical features,thereby making an attempt to construct tectonic discrimination *** on the data-driven pattern,all available elements were employed to derive logratios for the possible coordinates,and the overlap-rate calculation was adopted to evaluate the discrimination effect of more than 330000 prospective ***,four tectonic discrimination diagrams have been successfully established to identify MORA,PRA and OAA,which can be utilized to identify the original settings of andesite with an age range from Cenozoic to Archean a certain *** these diagrams,PRA is mainly distinguished by high LREE/HREE ratio due to enriched mantle ***,OAA is mainly characterized by high LILE/HFSE ratio,which reveals that fluids derived from subducted slab play an important role in forming oceanic arc ***,the petrogenesis of andesites is closely related to their tectonic ***,it should be noted that those andesites formed in both continental and oceanic environments cannot be effectively distinguished using these *** strongly recommend integrating the discrimination diagrams result with other geological information to reach a comprehensive interpretation of evolution history with those ancient *** paper presents a case study which suggests that data-driven method is a powerful tool for solving geological problems in this’big data’era.

关键词： andesite oceanic arc plume-related island mid-oceanic ridge tectonic discrimination diagrams geochemical data data analysis big data

New insights on the origin of the basement of the Xisha Uplift,South China Sea

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Science China Earth Sciences 2017年第12期60卷 2214-2222页

作者： ZHU WeiLin XIE XiNong WANG ZhenFeng zhang DaoJun zhang chengli CAO LiCheng SHAO Lei State Key Laboratory of Marine Geology Tongji University Shanghai 200092 China Key Laboratory of Tectonics and Petroleum Resources Ministry of EducationChina University of Geoscience(Wuhan)Wuhan 430074China Zhanjiang Branch CNOOC LimitedZhanjiang 524057China Department of Geology Northwestern UniversityXi'an 710069China

The study of basement geochronology provides crucial insights into the tectonic evolution of oceans. However, early studies on the basement of the Xisha Uplift were constrained by limited geophysical and seismic data; Xiyong1 was the only commercial borehole drilled during the 1970 s because of the huge thickness of overlying Cenozoic strata on the continental margin. Utilizing two newly-acquired basement samples from borehole XK1, we present petrological analysis and zircon uranium(U)-lead(Pb) isotope dating data in this paper that enhance our understanding of the formation and tectonic features of the Xisha Uplift basement. Results indicate that this basement is composed of Late Jurassic amphibole plagiogneisses that have an average zircon 206 Pb/238 U age of 152.9±1.7 Ma. However, the youngest age of these rocks, 137±1 Ma, also suggests that metamorphism termination within the Xisha basement occurred by the Early Cretaceous. These metamorphic rocks have adamellites underneath them which were formed by magmatic intrusions during the late stage of the Early Cretaceous(107.8±3.6 Ma). Thus, in contrast to the Precambrian age(bulk rubidium(Rb)-strontium(Sr) analysis, 627 Ma) suggested by previous work on the nearby Xiyong1 borehole, zircons from XK1 are likely the product of Late Mesozoic igneous activity. Late Jurassic-Early Cretaceous regional metamorphism and granitic intrusions are not confined to Xisha; rocks have also been documented from areas including the Pearl River Mouth Basin and the Nansha Islands(Spratly Islands) and thus are likely closely related to large-scale and long-lasting subduction of the paleo-Pacific plate underneath the continental margins of East Asia, perhaps the result of closure of the Meso-Tethys in the South China Sea(SCS). Controversies remain as to whether, or not, the SCS region developed initially on a uniform Precambrian-aged metamorphic crystalline basement. It is clear, however, that by this time both Mesozoic compressive subduct

关键词： South China Sea Xisha Islands Basement Mesozoic Zircon dating

Geochemistry of ophiolite cherts from the Qinling orogenic belt and implications for their tectonic settings

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Science China Earth Sciences 2004年第4期47卷 329-337页

作者： zhang chengli GAO Shan zhang Guowei GUO Anlin YUAN Honglin LIU Xiaoming WANG Jianqi The key Laboratory of Continental Dynamics Ministry of EducationDepartment of GeologyNorthwest UniversityXian 710069 China State Key Laboratory for Mineral Deposits Research Nanjing UniversityNanjing 210093China Department of Geochemistry China University of GeosciencesWuhan 430074China

Paleozoic cherts from the Mianl and the Erlangping ophiolite zones of the Qinling orogenic belt are characterized by low Si/Al ratios (52.14-683.52 in the Mianle cherts, 12.29-58.62 in the Erlangping cherts), Fe2O3 (0.01-0.35 and 0.02-1.24) and high Al2O3/(Al2O3+Fe2O3) ratios (0.82-0.99 and 0.83-0.99). The negative correlation between Si2O and Al2O3 in the cherts reflects the important role of terrigenous components. The Erlangping cherts have Lan/Cen=0.9-1.15 and Ce/Ce*=0.95-1.15 with low contents of V, Ni and Cu, consistent with those of cherts forming on the continental margin. In contrast, the Ce/Ce* ratios of the Mianle cherts range from 0.71 to 1.18 and Lan/Cen from 0.88 to 1.43 with slightly high V, Ni and Cu, which are similar to cherts found in the mid-ocean ridges and pelagic basins. Combined with the features of basic lavas associated with the cherts, it is suggested that during the Paleozoic, when the back-arc basin represented by the Erlangping ophiolite commenced shrinking in size in the mid-Ordovician, the southern Qinling was still in an extensional regime and finally grew into a new limited oceanic basin in the early Carboniferous.

关键词： Qinling orogenic belt radiolarian cherts ophiolite m閘ange zone.

North Qinling Paleozoic granite associations and their variation in space and time: Implications for orogenic processes in the orogens of central China

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Science China Earth Sciences 2009年第9期52卷 1359-1384页

作者： WANG Tao WANG XiaoXia TIAN Wei zhang chengli LI WuPing LI Shan Institute of Geology Chinese Academy of Geological ScienceBeijing 100037China Institute of Mineral and Resource Chinese Academy of Geological ScienceBeijing 100037China Department of Geology Peking UniversityBeijing 100871China Key Laboratory of Continental Dynamics of Northwest University Department of GeologyNorthwest UniversityXi’an 710069China School of Civil Engineering Guangzhou UniversityGuangzhou 510006China

Integrated zircon U-Pb dating and whole rock geochemical analyses have been carried out for two typical S-and I-type granitoids in the north Qinling. Zircon dating by SIMS of the Piaochi S-type grani- toids yields an emplacement age of 495±6 Ma. The granitoids show whole-rock εNd(t)=-8.2--8.8, zircon εHf(t)=-6―-39. The Huichizi I-type granitoids have emplacement ages of 421±27 Ma and 434±7 Ma es- tablished by LA-ICP-MS and SIMS methods, respectively. Their whole-rock εNd(t)=-0.9-0.9 and zircon εHf(t)=-11-8.4. Combined with statistical analyses of 28 zircon ages of granitoid plutons collected from the literature, Paleozoic magmatism in the north Qinling can be divided into three stages. The first-stage magmatism (~505-470 Ma) mainly occurred in the east part of the north Qinling and has features of an I-type arc, associated with which are S-type granitoids such as Piaochi pluton. The early granitoids (~505-490 Ma) have close spatio-temporal relations to ultra-high-pressure (UHP) rocks, and thus are interpreted as an oceanic subduction system along a continental margin. The second-stage magmatism (~450-422 Ma) occured through the whole north Qinling, and is characterized by I-type granitoids represented by the Huichizi pluton. The magma is interpreted as partial melting of lower crust mixed by mantle-derived magma in a collisional setting with the uplift of terranes. The third-stage magmatism (~415-400 Ma) is dominated by I-type granitoids and only took place in the middle part of the north Qinling, and is regarded as a late-stage collision. The spatial and temporal variations of the Qinling Paleozoic magmatism reveal protracted subduction/collision. The subduction was initiated from the east part of the north Qinling, earlier than that in the Qilian-northern Qaidam, Kunlun, and northern Dabie regions. This demonstrates variations in time of subduction, accretion and collision of separate blocks or terranes in the orogenic systems in central China.

关键词： zircon geochronology granite association Nd Hf isotopes Qinling orogen

Transient Model for Shafting Vibration of Hydro Turbine Generating Sets

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仪器仪表学报 2013年第S1期34卷 190-196页

作者： Zeng Yun zhang Lixiang zhang chengli Yu Fengrong Qian Jing Department of Engineering Mechanics Kunming University of Science and Technology Faculty of Metallurgical and Energy Engineering Kunming University of Science and Technology College of Electric Power Engineering Kunming University of Science and Technology

The shafting vibration is closely related to the rotational angular *** angular speed of hydro turbine generating sets(HTGS)is rapidly change in fault transient,it maybe reduce the shafting *** means of energy analysis,the differential equation of shafting vibration for the HTGS is derived,in which include the equation of generator rotor and hydro turbine runner,it can be applied to transient *** model is transformed into first order differential equation groups,and is combined with the motion equation of HTGS to build integrated *** additional forces of shafting are taken as input inspire in proposed model,the generality of model is *** last,the shafting vibration in emergency stop transient is simulated.

关键词： hydro turbine generating sets shafting vibration transient model fault

Challenges in applying REE-based thermobarometers: Insights from mafic-ultramafic granulites in Indian southern granulite terrain

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Science China Earth Sciences 2024年第11期67卷 3448-3464页

作者： Xiaofei XU Longlong GOU chengli zhang Junsheng LU Yan ZHAO Wenhao AO Yuhua HU Feng ZHOU Faculty of Land Resources Engineering Kunming University of Science and TechnologyKunming 650093China State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi’an 710069China

High-temperature diffusion of major elements may obscure the records of early and peak metamorphic stages in granulites,while trace elements are more likely to preserve these records due to their lower diffusion ***,using calibrated REE-based thermobarometers has proved essential for reconstructing these key stages,drawing considerable attention and application from ***,the precision of these thermobarometers depends on including both major and trace elements from coexisting minerals to define the correlation coefficients(A,B,and D) among mineral pairs,indicating that the elemental composition of these pairs can affect the *** study examines the mafic-ultramafic granulites in the southern granulite terrain,India,employing integrated methods such as petrography,mineral chemistry,phase equilibrium modeling,and REE-based *** aim to determine their metamorphic conditions and evolutionary history and to identify potential challenges in using REE-based *** garnet,clinopyroxene,and orthopyroxene in the mafic-ultramafic granulite samples display homogeneous compositional profiles,with pronounced Fe-Mg diffusion zones at the interfaces between garnet and ***,the profiles of trace elements within garnet and clinopyroxene are better *** into Fe-Mg exchange and randomly selected mineral pairs significantly influence the accuracy of REE-based ***-Mg exchange can increase in coefficient A,while decreasing coefficient B for light rare earth elements(LREEs) and increasing it for heavy rare earth elements(HREEs),ultimately resulting in overestimations when calculating REE-based *** example,selecting major compositions with an Ex(=(X_(Mg)^(C)-X_(Mg)^(0))/X_(Mg)^(0)×100%;where X_(Mg)^(C) is the value after Fe-Mg exchange,X_(Mg)^(0) is the value before Fe-Mg exchange;X_(Mg)=Mg/(Fe^(2+)+Mg)) value of ~10 for calculation using the REE-in-Grt-Cpx thermoba

关键词： Granulites REE-based thermobarometer Fe-Mg exchange Randomly selected mineral pairs

Geology and geochemistry of the Bingdaban ophiolitic mélange in the boundary fault zone on the northern Central Tianshan Belt,and its tectonic implications

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Science China Earth Sciences 2007年第1期50卷 17-24页

作者： DONG YunPeng zhang GuoWei ZHOU DingWu LUO JinHai zhang chengli XIA LinQi XU XueYi LI XiangMin The Key Laboratory of Continental Dynamics Ministry of EducationDepartment of GeologyNorthwest UniversityXi’an 710069China Shandong University of Science and Technology Qingdao 266510China Xi’an Institute of Geology and Mineral Resources China Geological SurveyXi’an 710054China

The properties and tectonic significance of the fault bound zone on the northern margin of the Central Tianshan belt are key issues to understand the tectonic framework and evolutionary history of the Tianshan Orogenic Belt. Based on the geological and geochemical studies in the Tianshan orogenic belt, it is suggested that the ophiolitic slices found in the Bingdaban area represent the remaining oceanic crust of the Early Paleozoic ocean between the Hazakstan and Zhungaer blocks. Mainly com-posed of basalts, gabbros and diabases, the ophiolites were overthrust onto the boundary fault be-tween the Northern Tianshan and Central Tianshan belts. The major element geochemistry is charac-terized by high TiO2 (1.50%-2.25%) and MgO (6.64%-9.35%), low K2O (0.06%-0.41%) and P2O5 (0.1%-0.2%), and Na2O>K2O as well. Low ΣREE and depletion in LREE indicate that the original magma was derived from a depleted mantle source. Compared with a primitive mantle, the geochemistry of the basalts from the Bingdaban area is featureded by depletion in Th, U, Nb, La, Ce and Pr, and unfrac-tionated in HFS elements. The ratios of Zr/Nb, Nb/La, Hf/Ta, Th/Yb and Hf/Th are similar to those of the typical N-MORB. It can be interpreted that the basalts in the Bingdaban area were derived from a de-pleted mantle source, and formed in a matured mid-oceanic ridge setting during the matured evolu-tionary stage of the Northern Tianshan ocean. In comparison with the basalts, the diabases from the Bingdaban area show higher contents of Al2O3, ∑REE and HFS elements as well as unfractionated incompatible elements except Cs, Rb and Ba, and about 10 times the values of the primitive mantle. Thus, the diabases are thought to be derived from a primitive mantle and similar to the typical E-MORB. The diabases also have slight Nb depletion accompanying no apparent Th enrichment compared with N-MORB. From studies of the regional geology and all above evidence, it can be suggested that the diabases from the Bingdaban

关键词： geochemistry ophiolite suture zone Bingdaban Tianshan orogenic belt.

Precipitation of rutile needles in garnet from sillimanite-bearing pelitic granulite from the Khondalite Belt, North China Craton

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Chinese Science Bulletin 2014年第2期59卷 4359-4366页

作者： Longlong Gou chengli zhang Lifei zhang Quan Wang State Key Laboratory of Continental Dynamics Department of Geology Northwest University Laboratory for Crustal Petrology Department of GeologyUniversity of Maryland College Park MD 20742 USA Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of Education School of Earth and Space SciencesPeking University Institute of Shanxi Geological Survey

Pelitic granulite from the Khondalite Belt,North China Craton,is composed of garnet,sillimanite,perthite,biotite and *** rutile needles in garnet are reported for the first time from the *** rutile needles have been identified by optical microscopy and confirmed by in situ Raman spectroscopy,where they show the characteristic bands at 446–448 and 610 *** of their very strong shape preferred orientation in3–4 easily observable directions,these rutile needles are interpreted to have formed by precipitation during exhumation and cooling following peak *** ternary feldspar geothermometer gives a peak metamorphic temperature of*980°C at 10 *** presence of oriented rutile needles in garnet is suggested to be a valuable indicator of ultrahigh-temperature(UHT)metamorphism in the Khondalite Belt and therefore likely in other UHT terrains.

关键词：中国北方金红石石榴石克拉通麻粒岩岩带泥质矽线石

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Early Paleozoic tectonic evolution of Qinling orogen-evidence from zircon U-Pb dating and Hf isotope of granitoids in north Qinling belt, central China

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地质学报 2013年第S1期 91-95页

作者： zhang chengli LIU Liang WANG Tao LI Lei LI Xiaofei State Key Laboratory of continental dynamics department of geology Northwest University Institute of Geology Chinese Academy of Geological Sciences

The Qinling orogen, as an important part of the central orogenic belt of China, underwent a long-term tectonic evolution, being a typical composite and multi-stage orogen. Its evolutionary history is critical for the ...

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