Highly evolved granite associated with pegmatite shells exhibits significant potential for rare metal mineralization;however,the mechanisms through which these pegmatite shells contribute to magmatic evolution and rar...Highly evolved granite associated with pegmatite shells exhibits significant potential for rare metal mineralization;however,the mechanisms through which these pegmatite shells contribute to magmatic evolution and rare metal enrichment remain poorly understood.The Late Jurassic Shihuiyao Nb-Ta-(Rb-Be-Li)deposit is one of the largest rare-metal deposits in the Southern Great Xing’an Range(SGXR),Northeast China.Exploratory trenches expose distinct layered zones from top to bottom:alternating microcline pegmatite and aplite layers(zone I),topaz lepidolite albite granite and lepidolite amazonite pegmatite(zone II),and muscovite albite granite(zoneⅢ).We conducted U-Pb dating of cassiterite,monazite,and Nb-Ta oxide,monazite Nd isotopes,and whole-rock and mineral geochemistry for the three zones.Multi-mineral U-Pb ages indicate that the three zones formed during the Late Jurassic-Early Cretaceous(147-142 Ma).Geochemical analyses of whole-rock,mica,and microcline suggest an evolutionary sequence from zone I to zoneⅢ,and finally to zone II.The Zr/Hf,Nb/Ta,Y/Ho,and K/Rb ratios combined with the rare earth element(REE)tetrad effects suggest higher degree of differentiation and fluid-melt interaction of the Shihuiyao leucogranite without a pegmatite shell compared to coeval barren granites from both Shihuiyao and the SGXR.A progressive increase in the degree of evolution is evident from the leucogranite without a pegmatite shell to the leucogranite with a discontinuous shell,and ultimately to the leucogranite with a continuous shell.The pegmatite shell acted as a geochemical barrier that facilitated the accumulation of Li and F in the underlying magma,which played a crucial role in lowering the solidus temperature of the granitic magma.This process prolonged the crystallization duration while reducing melt viscosity and density,thereby creating favorable conditions for magma differentiation and fluid-melt interaction.Rapid crystallization of the earlier water-and Be-rich melt led to the Be mineralization in the pegmatite shell.Moreover,the formation of this shell served as a barrier for Li mineralization in the underlying topaz lepidolite albite granite.This study enhances our understanding of the critical contribution of pegmatite shells to magmatic evolution and rare-metal mineralization.展开更多
Tarim Precambrian bedrocks are well exposed in the Kuluketage and Aksu areas, where twenty four samples were taken to reveal the denudation history of the northern Tarim Craton. Apatite fission track dating and therma...Tarim Precambrian bedrocks are well exposed in the Kuluketage and Aksu areas, where twenty four samples were taken to reveal the denudation history of the northern Tarim Craton. Apatite fission track dating and thermal history modeling suggest that the northern Tarim experienced multi-stage cooling events which were assumed to be associated with the distant effects of the Cimmerian orogeny and India-Eurasia collision in the past. But the first episode of exhumation in the northern Tarim, occurring in the mid-Permian to Triassic, is here suggested to be induced by docking of the Tarim Craton and final amalgamation of the Central Asian Orogenic Belt. The cooling event at ca. 170 Ma may be triggered by the Qiangtang-Eurasia collision. Widespread Cretaceous exhumation could be linked with docking of the Lhasa terrane in the late Jurassic. Cenozoic reheating and recooling likely occurred because of the northpropagating stress, however, this has not affected the northern Tarim much because the Tarim is characterized by rigid block-like motion.展开更多
The Kop ophiolite in NE Turkey,representing a forearc fragment of Neo-Tethys ocean,mainly consists of a paleoMoho transition zone(MTZ)and a harzburgitic upper mantle unit.The Kop MTZ locally contains cumulate
Tectonically emplaced peridotites from North Hebei Province, North China Craton, have retained an original harzburgite mineral assemblage of olivine （54%-58%） ＋ orthopyroxene （40%-46%） ＋minor clinopyroxene （〈1...Tectonically emplaced peridotites from North Hebei Province, North China Craton, have retained an original harzburgite mineral assemblage of olivine （54%-58%） ＋ orthopyroxene （40%-46%） ＋minor clinopyroxene （〈1%）＋spinel. Samples with honinite-like chemical compositions also coexist with these peridotites. The spinels within the peridotites have high-A1 end-members with A1203 content of 30 wt%-50 wt%, typical of mantle spinels. When compared with experimentally determined melt extraction trajectories, the harzburgites display a high degree of melting and enrichment of SiO2, which is typical of cratonic mantle peridotites. The peridotites display variably enriched light rare earth elements （REEs）, relatively depleted middle REEs and weakly fractionated heavy REEs, which suggest a melt extraction of over 25% in the spinel stability field. The occurrence of are- and SSZ-type chromian spinels in the peridotites suggests that melt extraction and metasomatism occurred mostly in a subduction-related setting. This is also supported by the geochemical data of the coexisting boninite-like samples. The peridotites have lS7Os/lSSOs ratios ranging from 0.113-0.122, which is typical of cratonic iithospheric mantle. These lSTOs/ISSOs ratios yield model melt extraction ages （TRD） ranging from 981 Ma to 2054 Ma, which may represent the minimum estimation of the melt extraction age. The Ai203- lSTOs/lSSOs-proxy isochron ages of 2.4 Ga-2.7 Ga suggest a mantle melt depletion age between the Late Achaean and Early Paleoproterozoic. Both the peridotites and boninite-like rocks are therefore interpreted as tectonically exhumed continental lithospheric mantle of the North China Craton, which has experienced mantle melt depletion and subduction-related mantle metasomatism during the Neoarchean- Paleoproterozoic.展开更多
Considering the Neo-Tethyan tectonic process and the resulting environmental changes,a geodynamic model of“one-way train loading”is proposed to analyze the formation and evolution mechanism of the Persian Gulf Super...Considering the Neo-Tethyan tectonic process and the resulting environmental changes,a geodynamic model of“one-way train loading”is proposed to analyze the formation and evolution mechanism of the Persian Gulf Superbasin with the most abundant hydrocarbons in the world.The Persian Gulf Superbasin has long been in a passive continental margin setting since the Late Paleozoic in the process of unidirectional subduction,forming a superior regional space of hydrocarbon accu-mulation.During the Jurassic-Cretaceous,the Persian Gulf Superbasin drifted slowly at low latitudes,and developed multiple superimposed source-reservoir-caprock assemblages as a combined result of several global geological events such as the Hadley Cell,the Equatorial Upwelling Current,and the Jurassic True Polar Wander.The collision during the evolution of the foreland basin since the Cenozoic led to weak destruction,which was conducive to the preservation of oil and gas.Accordingly,it is be-lieved that the slow drifting and long retention in favorable climate zone of the continent are the critical factors for hydrocarbon enrichment.Moreover,the prospects of hydrocarbon potential in other continents in the Neo-Tethyan were proposed.展开更多
The Kop ophiolite in NE Turkey is a fragment of Neo-Tethyan forearc.It can be mainly divided into a paleo-Moho transition zone(MTZ)in the North and a harzburgitic mantle sequence in the South.Dunites are predominant i...The Kop ophiolite in NE Turkey is a fragment of Neo-Tethyan forearc.It can be mainly divided into a paleo-Moho transition zone(MTZ)in the North and a harzburgitic mantle sequence in the South.Dunites are predominant in the MTZ of the Kop ophiolite,and they are locally interlayered with chromitites and enclose minor bodies of harzburgites near the petrological Moho boundary.Large Fe isotopic variations were observed for magnesiochromite(-0.14‰to 0.06‰)and olivine(-0.12‰to 0.14‰)from the MTZ chromitites,dunites and harzburgites.In individual dunite samples,magnesiochromite usually has lighter Fe isotopic compositions than olivine,which was probably caused by subsolidus Mg-Fe exchange between the two mineral phases.Both magnesiochromite and olivine display an increasing trend ofδ56Fe along a profile from chromitite todunite.This trend reflects continuous fractional crystallization in a magma chamber,which resulted in heavier Fe isotopes concentrated in the evolved magmas.In each cumulative cycle of chromitite and dunite,dunite was formed from relatively evolved melts after massive precipitation of magnesiochromite.Mixing of more primitive and evolved melts in the magma chamber was a potential mechanism for triggering the crystallization of magnesiochromite,generating chromitite layers in the cumulate pile.Before mixing happened,the primitive melts had reacted with mantle harzburgites during their ascendance;whereas the evolved melts may lie on the olivine-chromite cotectic near the liquidus field of pyroxene.Variable degrees of magma mixing and differentiation are expected to generate melts with differentδ56Fe values,accounting for the Fe isotopic variations of the Kop MTZ.展开更多
The buildup of oxygen in the Earth＇s atmosphere and oceans has fundamentally reshaped the dynamics of nearly all major biogeochemical cycles and ultimately paved the way for the diversification of complex life on Ear...The buildup of oxygen in the Earth＇s atmosphere and oceans has fundamentally reshaped the dynamics of nearly all major biogeochemical cycles and ultimately paved the way for the diversification of complex life on Earth. Over the past decades there have been sustained efforts to develop a more comprehensive understanding of ocean-atmosphere redox evolution and its relationship to the evolution of early life （Fig. 1）. It is generally accepted that the development of oxygenic photosynthesis at ~2.7 Ga may have been responsible for the Great Oxidation Event （GOE） at the beginning of the Proterozoic Eon, whereas a second big O2 rise at the end of the Proterozoic Eon （the so-called Neoproterozoic Oxidation Event or NOE） was responsible for the diversification of metazoans （Lyons et al., 2014）.展开更多
In this study, zircon U-Pb ages, geochemical and Lu-Hf isotopic data are presented for the newly identified volcanic rocks which were considered as Bainaimiao group in Bainaimiao Arc Belt(BAB), Inner Mongolia, which c...In this study, zircon U-Pb ages, geochemical and Lu-Hf isotopic data are presented for the newly identified volcanic rocks which were considered as Bainaimiao group in Bainaimiao Arc Belt(BAB), Inner Mongolia, which could provide important constraints on the evolution of the northern part of North China Block(NCB) and BAB. Basalt to basaltic andesite and andesite to dacite were collected from two sections, which showed eruption ages of 278.2±4.1 Ma and 258.3±3.0 Ma respectively. All samples are characterized by high abundances in Al2O3, LREEs, and LILEs, but depleted in HFSEs. Together with high Mg# ratios and low K/tholeiite to calc-alkaline series, these features indicated that basalt to andesite was likely derived from relatively low degree partial melting of the subduction-fluid related mantle in the spinel phase. And dacite was mainly from the partial melting of crust, then affected by mantle. All samples barely went through fractional crystallization process with the slight Eu anomaly. Compared with the contemporary basalt in NCB, rocks in BAB have a complex composition of zircon and a more positive εHf(t) value(-6.6-6.4), indicating that they had different magma sources of rocks. Though with different basements, NCB and BAB have become an integrated whole before 278 Ma. Therefore, it could be concluded that NCB and BAB belonged to the active continental margin and the PAO had not closed yet until late Permian and then it disappeared gradually and the CAOB developed into a condition of syn-post collision.展开更多
Thermal diffusivity(D)and thermal conductivity(κ)of harzburgite and dunite from Luobusha ophiolite were simultaneously measured up to 3 GPa and 823 K using the transient plane-source method in a multi anvil apparatus...Thermal diffusivity(D)and thermal conductivity(κ)of harzburgite and dunite from Luobusha ophiolite were simultaneously measured up to 3 GPa and 823 K using the transient plane-source method in a multi anvil apparatus.The results show that the values of D andκof both samples systematically decrease with increasing temperature and increase with increasing pressure.By combination of the thermal physical data of rocks and minerals and geophysical constraints,we performed numerical simulation on the thermal evolution of Tibet vary over depth,distance and geologic ages.The present results provide new constraints on occurrence of partial melting and its geophysical significance beneath Tibetan crust.展开更多
The Tianshan orogenic belt is a major part of the southern Central Asian Orogenic Belt（CAOB）,extending from west to east for over 2500 km through Uzbekistan,Tajikistan,Kyrgyzstan and Kazakhstan to Xinjiang in NW Chi...The Tianshan orogenic belt is a major part of the southern Central Asian Orogenic Belt（CAOB）,extending from west to east for over 2500 km through Uzbekistan,Tajikistan,Kyrgyzstan and Kazakhstan to Xinjiang in NW China,and contains the record of multi-phase tectonothermal evolution.Till now.展开更多
The Liwan Sag,with an area of 4000 km-2,is one of the deepwater sags in the Zhujiang River(Pearl River)Mouth Basin,northern South China Sea.Inspired by the exploration success in oil and gas resources in the deepwater...The Liwan Sag,with an area of 4000 km-2,is one of the deepwater sags in the Zhujiang River(Pearl River)Mouth Basin,northern South China Sea.Inspired by the exploration success in oil and gas resources in the deepwater sags worldwide,we conducted the thermal modeling to investigate the tectono-thermal history of the Liwan Sag,which has been widely thought to be important to understand tectonic activities as well as hydrocarbon potential of a basin.Using the multi-stage finite stretching model,the tectonic subsidence history and the thermal history have been obtained for 12 artificial wells,which were constructed on basis of one seismic profile newly acquired in the study area.Two stages of rifting during the time periods of 49–33.9 Ma and 33.9–23 Ma can be recognized from the tectonic subsidence pattern,and there are two phases of heating processes corresponding to the rifting.The reconstructed average basal paleo-heat flow values at the end of the rifting events are-70.5 and-94.2 mW/m^2 respectively.Following the heating periods,the study area has undergone a persistent thermal attenuation phase since 23 Ma and the basal heat flow cooled down to-71.8–82.5 mW/m^2 at present.展开更多
The regular variations in magmatic activities along the Northwest Pacific plate have been little studied in spite of their importance. In this contribution, systematic analyses were conducted on tholeiitic basalts fro...The regular variations in magmatic activities along the Northwest Pacific plate have been little studied in spite of their importance. In this contribution, systematic analyses were conducted on tholeiitic basalts from three Ocean Drilling Program sites(Sites 304, 1149, and 801), including the petrographic features, major and trace elements, Nd isotopic compositions, and mineral structure and compositions of whole rocks. Volcanic rocks from Sites 304, 1149, and 801 belong to tholeiites and exhibit depleted light rare earth elements(LREE), large ion lithophile elemental contents(LILE), and relatively depleted Nd isotopic ratios(143Nd/144Nd=0.513139-0.513211), similar to those of normal mid-ocean ridge basalts(NMORB). Comprehensive data on mineral compositions, whole-rock geochemistry, and geochronology demonstrate that a regular variation trend exists in the north-south direction along the Northwest Pacific plate. The 143 Nd/144 Nd values(0.513139-0.513211) and trace-element ratios for whole rocks(Sm/Th=15.35-30.00; Zr/Hf=28.53-35.76; Zr/Y=2.58-3.67; Th/La=0.04-0.06; Th/Y=0.33-0.70), as well as the trace-element ratios(Zr/Hf, La/Yb, Ti/Zr) of clinopyroxenes from Sites 1149 and 801 tholeiites show larger variations compared to those from Site 304 tholeiites(143Nd/144Nd=0.513185-0.513195; Sm/Th=18.19-20.58; Zr/Hf=31.07-33.26; Zr/Y=2.62-3.03; Th/La=0.05-0.06; Th/Y=0.48-0.57). Mineral zoning textures were obvious in tholeiites from Sites 1149 and 801 but were rarely observed in Site 304.These regular features were likely attributed to the differences in the heterogeneity of the magma source,the process of magmatic evolution, the plate-spreading rate, and the effective and ineffective mixing.展开更多
Plate subduction leads to complex exhumation processes on continents.The Huangling Massif lies at the northern margin of the South China Block.Whether the Huangling Massif was exhumed as a watershed of the middle reac...Plate subduction leads to complex exhumation processes on continents.The Huangling Massif lies at the northern margin of the South China Block.Whether the Huangling Massif was exhumed as a watershed of the middle reaches of the Paleo-Yangtze River during the Mesozoic remains under debate.We examined the exhumation history of the Huangling Massif based on six granite bedrock samples,using apatite fission track(AFT)and apatite and zircon(U-Th)/He(AHe and ZHe)thermochronology.These samples yielded ages of 157–132 Ma(ZHe),119–106 Ma(AFT),and 114–72 Ma(AHe),respectively.Thermal modeling revealed that three phases of rapid cooling occurred during the Late Jurassic–Early Cretaceous,late Early Cretaceous,and Late Cretaceous.These exhumation processes led to the high topographic relief responsible for the emergence of the Huangling Massif.The integrated of our new data with published sedimentological records suggests that the Huangling Massif might have been the watershed of the middle reaches of the Paleo-Yangtze River since the Cretaceous.At that time,the rivers flowed westward into the Sichuan Basin and eastward into the Jianghan Basin.The subduction of the Pacific Plate beneath the Asian continent in the Mesozoic deeply influenced the geomorphic evolution of the South China Block.展开更多
The Trans-North China Belt(TNCB)is a Paleoproterozoic collisional orogen(ca.1.9-1.8 Ga)responsible for the amalgamation of the North China Craton.Detailed field works in Liiliangshan,Hengshan,Wutaishan and Fuping mass...The Trans-North China Belt(TNCB)is a Paleoproterozoic collisional orogen(ca.1.9-1.8 Ga)responsible for the amalgamation of the North China Craton.Detailed field works in Liiliangshan,Hengshan,Wutaishan and Fuping massifs where the belt is well exposed,allow us to draw a new tectonic map and crustal-scale cross sections.The available petrologic,radiometric,geochronologic data are integrated in a geodynamic evolution scheme for this orogen.The Low Grade Mafic Unit(LGMU)is interpreted as an ophiolitic nappe rooted in a suture zone located in the western part of the Lüliangshan.This ophiolitic nappe overthrusts to the SE upon the Orthogneiss-Volcanites Unit(OVU)that consists of a bimodal volcanic-sedimentary series metamorphosed under amphibolite facies conditions intruded by calcalkaline orthogneiss.The OVU is a composite Neoarchean-Paleoproterozoic magmatic arc developed during two stages(ca.2500 and 2100 Ma)upon a continental basement corresponding to the western extension of the Neoarchean Fuping massif The OVU overthrusts to the SE the Fuping massif along the Longquanguan shear zone.This stack of nappes,coeval with an amphibolite facies metamorphism,is dated at ca.1880 Ma.Subsequently,the metamorphic series experienced a widespread migmatization at 1850 Ma and was intruded by post-orogenic plutons dated at 1800 Ma.The weakly to unmetamorphosed Hutuo Supergroup unconformably overlies the metamorphosed and ductilely deformed units(OVU and LGMU),but it is also involved in a second tectonic phase developed in subsurface conditions.These structural features lead us to question the ca.2090 Ma age attributed to the Hutuo supergroup.Moreover,in the Fuping massif several structural and magmatic lines of evidence argue for an earlier orogenic event at ca.2100 Ma that we relate to an older west-directed subduction below the Fuping Block.The Taihangshan Fault might be the location of a possible suture zone between the Fuping Block and an eastern one.A geodynamic model at variance with previous ones,is proposed to account for the formation of the TNCB.In this scheme,three Archean continents,namely from west to east,the Ordos,Fuping and Eastern Blocks are separated by the Lüliang and Taihang Oceans.The closure of the Taihang Ocean at ca.2100 Ma by westward subduction below the Fuping Block accounts for the arc magmatism and the 2100 Ma orogeny.The second collision at 1900-1880 Ma between the Fuping and Ordos blocks is responsible for the main structural metamorphic and magmatic features of the Trans-North China Belt.展开更多
The Chinese Tianshan Belt is one of the key regions for the understanding of tectonics of the Central Asian Orogenic Belt(CAOB).An international field excursion and workshop were organized to conduct a common observat...The Chinese Tianshan Belt is one of the key regions for the understanding of tectonics of the Central Asian Orogenic Belt(CAOB).An international field excursion and workshop were organized to conduct a common observation and discussion on the tectonic evolution of the Chinese Tianshan.This report summarizes the main achievements,including acknowledged geological features,controversial and remaining scientific problems,and discussion of a tentative geodynamic model.Thus,it is helpful to clarify what has been done in the past,what should be improved and what needs to be done in the future and therefore to better understand the tectonics of the Chinese Tianshan Belt and the CAOB as well.展开更多
To define a tectonic environment switching from rifting to subduction and their respective duration time are usually largely debated.Such case occurs for the Liaohe rift:whether it went through a long subduction from ...To define a tectonic environment switching from rifting to subduction and their respective duration time are usually largely debated.Such case occurs for the Liaohe rift:whether it went through a long subduction from 2100to 1850 Ma or there were two different events in different展开更多
The nature(i.e., sub-oceanic, sub-arc or subcontinental) of ophiolitic mantle peridotites from the eastern Neo-Tethyan domain in southern Tibet has been hotly debated. This uncertainty limits our understanding of the ...The nature(i.e., sub-oceanic, sub-arc or subcontinental) of ophiolitic mantle peridotites from the eastern Neo-Tethyan domain in southern Tibet has been hotly debated. This uncertainty limits our understanding of the history and evolution of the eastern Neo-Tethys Ocean. Here we present petrological, geochemical and Re-Os isotopic data for the mantle peridotites from the Dazhuqu ophiolite in the central segment of the Yarlung Zangbo suture zone, southern Tibet. Samples collected include both spinel lherzolites and spinel harzburgites. The lherzolites have spinel Cr~# [Cr/(Cr + Al), ~ 0.3–0.4] comparable to those of typical abyssal peridotites. In contrast, the harzburgites have spinel Cr~#(~0.3–0.7) overlapping with the ranges of both abyssal and fore-arc peridotites(Day et al., 2017;Parkinson and Pearce, 1998);two samples have spinel Cr~# higher than 0.6, which is probably ascribed to intense melt-rock interactions. Clinopyroxene trace element modeling indicates that the Dazhuqu mantle peridotites have experienced 0–6% garnetfacies melting followed by 10% –18% melting in the spinel stability field. This is similar to the degree of garnet-facies melting inferred for many abyssal peridotites(Hellebrand et al., 2002) and implies deep initial melting(> 85 km), which distinguishes the Dazhuqu mantle peridotites from fore-arc peridotites(commonly <80 km in origin). The Dazhuqu peridotites have unradiogenic 187 Os/188 Os of 0.11836–0.12922, which are commonly lower than the recommended value of primitive upper mantle(PUM)(Meisel et al., 2001). All but one samples yield relatively younger Re depletion ages(TRD = 0.06–0.81 Ga) with respect to the only one sample having an older TRD age of 1.66 Ga. Re-Os isotopes and highly siderophile element(HSE) compositions of the Dazhuqu peridotites are similar to those of abyssal peridotites(Day et al., 2017) and the Oman southern massifs(Hangh?j et al., 2010) but are distinct from noncratonic sub-continental lithospheric mantle(SCLM) xenoliths and sub-arc mantle. We emphasize the similarity between the Dazhuqu and Oman ophiolites, both representing Neo-Tethyan oceanic lithosphere and implying ridge–trench collision.展开更多
Ophiolites along the E-W trending Yarlung-Tsangpo Suture(YTS),which separates the Indian plate from the Eurasian plate,have been regarded as relics of the NeoTethyan Ocean.The Xigaze ophiolite in the central YTS
Seventeen new ^40Ar/^39Ar analyses reported for ten Tarim Precambrian basement samples from the Kuluketage area, are applied to reconstruct the regional thermo-tectonic history together with previously published data....Seventeen new ^40Ar/^39Ar analyses reported for ten Tarim Precambrian basement samples from the Kuluketage area, are applied to reconstruct the regional thermo-tectonic history together with previously published data. Eight samples were taken adjacent to the Xingdi and Xinger faults, major structures in the study area, whereas a further two were sampled at some distance from the faults. 4^40Ar/^39Ar data from the latter record rapid cooling following a Neoproterozoic magmatic/metamorphic event and mild Paleozoic thermal disturbance. Paleozoic ^40Ar/^39Ar ages from the study area, as well as from the Central Tianshan and eastern Southern Tianshan suggest two strong deformational periods at ~390 Ma and ~300 Ma. During the older period, argon isotopic systems were reset/disturbed by high temperature related to arc magmatism resulting from subduction of the South Tianshan paleo-oceanic crust, possibly in combination with reactivation of Precambrian faults. The younger period is characterized by widespread late Carboniferous-early Permian intracontinental deformation, which is related to the final amalgamation of the Central Asian Orogenic Belt. Previously published apatite fission track data attest to a long history of post-collisional cooling, which is attributed to continued propagation of deformation within the Central Asian Orogenic Belt.展开更多
The South China block(SC),composed of Cathaysia(CA),Jiangnan Orogenic belt(JNB),and Yangtze block(YB),is one of the most important poly-metallic metallogenic provinces in the world(Zhang et al.,2013),containing of fou...The South China block(SC),composed of Cathaysia(CA),Jiangnan Orogenic belt(JNB),and Yangtze block(YB),is one of the most important poly-metallic metallogenic provinces in the world(Zhang et al.,2013),containing of four famous major Mesozoic metallogenic belts,involving the Middle-Lower Yangtze Fe-Cu-Au metallogenic belt(MYMB).展开更多
基金supported by the Key Research Program of the Institute of Geology&Geophysics,CAS(IGGCAS-202205)the National Natural Science Foundation of China(Grant No.92062216 and 42102046)+1 种基金Doctoral Students'Scientific Research and Innovation Capability Enhancement Program of Jilin Province(JJKH20250074BS)Graduate Innovation Fund of Jilin University(2024CX231).
文摘Highly evolved granite associated with pegmatite shells exhibits significant potential for rare metal mineralization;however,the mechanisms through which these pegmatite shells contribute to magmatic evolution and rare metal enrichment remain poorly understood.The Late Jurassic Shihuiyao Nb-Ta-(Rb-Be-Li)deposit is one of the largest rare-metal deposits in the Southern Great Xing’an Range(SGXR),Northeast China.Exploratory trenches expose distinct layered zones from top to bottom:alternating microcline pegmatite and aplite layers(zone I),topaz lepidolite albite granite and lepidolite amazonite pegmatite(zone II),and muscovite albite granite(zoneⅢ).We conducted U-Pb dating of cassiterite,monazite,and Nb-Ta oxide,monazite Nd isotopes,and whole-rock and mineral geochemistry for the three zones.Multi-mineral U-Pb ages indicate that the three zones formed during the Late Jurassic-Early Cretaceous(147-142 Ma).Geochemical analyses of whole-rock,mica,and microcline suggest an evolutionary sequence from zone I to zoneⅢ,and finally to zone II.The Zr/Hf,Nb/Ta,Y/Ho,and K/Rb ratios combined with the rare earth element(REE)tetrad effects suggest higher degree of differentiation and fluid-melt interaction of the Shihuiyao leucogranite without a pegmatite shell compared to coeval barren granites from both Shihuiyao and the SGXR.A progressive increase in the degree of evolution is evident from the leucogranite without a pegmatite shell to the leucogranite with a discontinuous shell,and ultimately to the leucogranite with a continuous shell.The pegmatite shell acted as a geochemical barrier that facilitated the accumulation of Li and F in the underlying magma,which played a crucial role in lowering the solidus temperature of the granitic magma.This process prolonged the crystallization duration while reducing melt viscosity and density,thereby creating favorable conditions for magma differentiation and fluid-melt interaction.Rapid crystallization of the earlier water-and Be-rich melt led to the Be mineralization in the pegmatite shell.Moreover,the formation of this shell served as a barrier for Li mineralization in the underlying topaz lepidolite albite granite.This study enhances our understanding of the critical contribution of pegmatite shells to magmatic evolution and rare-metal mineralization.
基金financially supported by 973 Program(Grant No. 2014CB440801)NSFC(Grant Nos.41230207 and 41302167)+1 种基金China Postdoctoral Council(Grant Nos.20100480452,2012T50135 and International Postdoctoral Exchange Fellowship)State Key Laboratory of Earthquake Dynamics(Grant No.LED2013B03)
文摘Tarim Precambrian bedrocks are well exposed in the Kuluketage and Aksu areas, where twenty four samples were taken to reveal the denudation history of the northern Tarim Craton. Apatite fission track dating and thermal history modeling suggest that the northern Tarim experienced multi-stage cooling events which were assumed to be associated with the distant effects of the Cimmerian orogeny and India-Eurasia collision in the past. But the first episode of exhumation in the northern Tarim, occurring in the mid-Permian to Triassic, is here suggested to be induced by docking of the Tarim Craton and final amalgamation of the Central Asian Orogenic Belt. The cooling event at ca. 170 Ma may be triggered by the Qiangtang-Eurasia collision. Widespread Cretaceous exhumation could be linked with docking of the Lhasa terrane in the late Jurassic. Cenozoic reheating and recooling likely occurred because of the northpropagating stress, however, this has not affected the northern Tarim much because the Tarim is characterized by rigid block-like motion.
文摘The Kop ophiolite in NE Turkey,representing a forearc fragment of Neo-Tethys ocean,mainly consists of a paleoMoho transition zone(MTZ)and a harzburgitic upper mantle unit.The Kop MTZ locally contains cumulate
基金financially supported by the NSFC(grant no.41430207, 41602340)China Postdoctoral Science Foundation ( 2016M591246)
文摘Tectonically emplaced peridotites from North Hebei Province, North China Craton, have retained an original harzburgite mineral assemblage of olivine （54%-58%） ＋ orthopyroxene （40%-46%） ＋minor clinopyroxene （〈1%）＋spinel. Samples with honinite-like chemical compositions also coexist with these peridotites. The spinels within the peridotites have high-A1 end-members with A1203 content of 30 wt%-50 wt%, typical of mantle spinels. When compared with experimentally determined melt extraction trajectories, the harzburgites display a high degree of melting and enrichment of SiO2, which is typical of cratonic mantle peridotites. The peridotites display variably enriched light rare earth elements （REEs）, relatively depleted middle REEs and weakly fractionated heavy REEs, which suggest a melt extraction of over 25% in the spinel stability field. The occurrence of are- and SSZ-type chromian spinels in the peridotites suggests that melt extraction and metasomatism occurred mostly in a subduction-related setting. This is also supported by the geochemical data of the coexisting boninite-like samples. The peridotites have lS7Os/lSSOs ratios ranging from 0.113-0.122, which is typical of cratonic iithospheric mantle. These lSTOs/ISSOs ratios yield model melt extraction ages （TRD） ranging from 981 Ma to 2054 Ma, which may represent the minimum estimation of the melt extraction age. The Ai203- lSTOs/lSSOs-proxy isochron ages of 2.4 Ga-2.7 Ga suggest a mantle melt depletion age between the Late Achaean and Early Paleoproterozoic. Both the peridotites and boninite-like rocks are therefore interpreted as tectonically exhumed continental lithospheric mantle of the North China Craton, which has experienced mantle melt depletion and subduction-related mantle metasomatism during the Neoarchean- Paleoproterozoic.
基金Supported by the International Cooperation Program of Chinese Academy of Sciences (GJHZ1776)National Natural Science Foundation of China (91855207)
文摘Considering the Neo-Tethyan tectonic process and the resulting environmental changes,a geodynamic model of“one-way train loading”is proposed to analyze the formation and evolution mechanism of the Persian Gulf Superbasin with the most abundant hydrocarbons in the world.The Persian Gulf Superbasin has long been in a passive continental margin setting since the Late Paleozoic in the process of unidirectional subduction,forming a superior regional space of hydrocarbon accu-mulation.During the Jurassic-Cretaceous,the Persian Gulf Superbasin drifted slowly at low latitudes,and developed multiple superimposed source-reservoir-caprock assemblages as a combined result of several global geological events such as the Hadley Cell,the Equatorial Upwelling Current,and the Jurassic True Polar Wander.The collision during the evolution of the foreland basin since the Cenozoic led to weak destruction,which was conducive to the preservation of oil and gas.Accordingly,it is be-lieved that the slow drifting and long retention in favorable climate zone of the continent are the critical factors for hydrocarbon enrichment.Moreover,the prospects of hydrocarbon potential in other continents in the Neo-Tethyan were proposed.
文摘The Kop ophiolite in NE Turkey is a fragment of Neo-Tethyan forearc.It can be mainly divided into a paleo-Moho transition zone(MTZ)in the North and a harzburgitic mantle sequence in the South.Dunites are predominant in the MTZ of the Kop ophiolite,and they are locally interlayered with chromitites and enclose minor bodies of harzburgites near the petrological Moho boundary.Large Fe isotopic variations were observed for magnesiochromite(-0.14‰to 0.06‰)and olivine(-0.12‰to 0.14‰)from the MTZ chromitites,dunites and harzburgites.In individual dunite samples,magnesiochromite usually has lighter Fe isotopic compositions than olivine,which was probably caused by subsolidus Mg-Fe exchange between the two mineral phases.Both magnesiochromite and olivine display an increasing trend ofδ56Fe along a profile from chromitite todunite.This trend reflects continuous fractional crystallization in a magma chamber,which resulted in heavier Fe isotopes concentrated in the evolved magmas.In each cumulative cycle of chromitite and dunite,dunite was formed from relatively evolved melts after massive precipitation of magnesiochromite.Mixing of more primitive and evolved melts in the magma chamber was a potential mechanism for triggering the crystallization of magnesiochromite,generating chromitite layers in the cumulate pile.Before mixing happened,the primitive melts had reacted with mantle harzburgites during their ascendance;whereas the evolved melts may lie on the olivine-chromite cotectic near the liquidus field of pyroxene.Variable degrees of magma mixing and differentiation are expected to generate melts with differentδ56Fe values,accounting for the Fe isotopic variations of the Kop MTZ.
文摘The buildup of oxygen in the Earth＇s atmosphere and oceans has fundamentally reshaped the dynamics of nearly all major biogeochemical cycles and ultimately paved the way for the diversification of complex life on Earth. Over the past decades there have been sustained efforts to develop a more comprehensive understanding of ocean-atmosphere redox evolution and its relationship to the evolution of early life （Fig. 1）. It is generally accepted that the development of oxygenic photosynthesis at ~2.7 Ga may have been responsible for the Great Oxidation Event （GOE） at the beginning of the Proterozoic Eon, whereas a second big O2 rise at the end of the Proterozoic Eon （the so-called Neoproterozoic Oxidation Event or NOE） was responsible for the diversification of metazoans （Lyons et al., 2014）.
基金supported by the National Natural Science Foundation of China (41872203, 41872194)the China Geological Survey Project (DD2016041–16,DD20190038–2)
文摘In this study, zircon U-Pb ages, geochemical and Lu-Hf isotopic data are presented for the newly identified volcanic rocks which were considered as Bainaimiao group in Bainaimiao Arc Belt(BAB), Inner Mongolia, which could provide important constraints on the evolution of the northern part of North China Block(NCB) and BAB. Basalt to basaltic andesite and andesite to dacite were collected from two sections, which showed eruption ages of 278.2±4.1 Ma and 258.3±3.0 Ma respectively. All samples are characterized by high abundances in Al2O3, LREEs, and LILEs, but depleted in HFSEs. Together with high Mg# ratios and low K/tholeiite to calc-alkaline series, these features indicated that basalt to andesite was likely derived from relatively low degree partial melting of the subduction-fluid related mantle in the spinel phase. And dacite was mainly from the partial melting of crust, then affected by mantle. All samples barely went through fractional crystallization process with the slight Eu anomaly. Compared with the contemporary basalt in NCB, rocks in BAB have a complex composition of zircon and a more positive εHf(t) value(-6.6-6.4), indicating that they had different magma sources of rocks. Though with different basements, NCB and BAB have become an integrated whole before 278 Ma. Therefore, it could be concluded that NCB and BAB belonged to the active continental margin and the PAO had not closed yet until late Permian and then it disappeared gradually and the CAOB developed into a condition of syn-post collision.
基金Key Research Program of Frontier Sciences of CAS(ZDBS-LY-DQC015)National Natural Science Foundation of China(Nos.41973056,41773056,41303048)Science Foundation of Guizhou Province(2017-1196,2018-1176).
文摘Thermal diffusivity(D)and thermal conductivity(κ)of harzburgite and dunite from Luobusha ophiolite were simultaneously measured up to 3 GPa and 823 K using the transient plane-source method in a multi anvil apparatus.The results show that the values of D andκof both samples systematically decrease with increasing temperature and increase with increasing pressure.By combination of the thermal physical data of rocks and minerals and geophysical constraints,we performed numerical simulation on the thermal evolution of Tibet vary over depth,distance and geologic ages.The present results provide new constraints on occurrence of partial melting and its geophysical significance beneath Tibetan crust.
基金supported by the Major Basic Research Project of the Ministry of Science and Technology of China(Grant No.2014CB448000)National Science Foundation of China(Grant Nos..41473053 and 41573045)a grant of Chinese Ministry of Land and Resources(Grant No.201211074–05)
文摘The Tianshan orogenic belt is a major part of the southern Central Asian Orogenic Belt（CAOB）,extending from west to east for over 2500 km through Uzbekistan,Tajikistan,Kyrgyzstan and Kazakhstan to Xinjiang in NW China,and contains the record of multi-phase tectonothermal evolution.Till now.
基金The Program of the Key Technologies for Petroleum Exploration in Deep Oceanic Areas under contract No.2011ZX05025-006-05the Chinese Postdoc Fund,No.58 General Fund,2015 under contract No.2015M582636the National Natural Science Foundation of China under contract No.41602251
文摘The Liwan Sag,with an area of 4000 km-2,is one of the deepwater sags in the Zhujiang River(Pearl River)Mouth Basin,northern South China Sea.Inspired by the exploration success in oil and gas resources in the deepwater sags worldwide,we conducted the thermal modeling to investigate the tectono-thermal history of the Liwan Sag,which has been widely thought to be important to understand tectonic activities as well as hydrocarbon potential of a basin.Using the multi-stage finite stretching model,the tectonic subsidence history and the thermal history have been obtained for 12 artificial wells,which were constructed on basis of one seismic profile newly acquired in the study area.Two stages of rifting during the time periods of 49–33.9 Ma and 33.9–23 Ma can be recognized from the tectonic subsidence pattern,and there are two phases of heating processes corresponding to the rifting.The reconstructed average basal paleo-heat flow values at the end of the rifting events are-70.5 and-94.2 mW/m^2 respectively.Following the heating periods,the study area has undergone a persistent thermal attenuation phase since 23 Ma and the basal heat flow cooled down to-71.8–82.5 mW/m^2 at present.
基金supported by the National Natural Science Foundation of China (Grant code: 41476034, 41272369, 40802038, and 41320104006)research funds from State Key Laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, Chinese Academy of Sciences (Grant code: 81300001)
文摘The regular variations in magmatic activities along the Northwest Pacific plate have been little studied in spite of their importance. In this contribution, systematic analyses were conducted on tholeiitic basalts from three Ocean Drilling Program sites(Sites 304, 1149, and 801), including the petrographic features, major and trace elements, Nd isotopic compositions, and mineral structure and compositions of whole rocks. Volcanic rocks from Sites 304, 1149, and 801 belong to tholeiites and exhibit depleted light rare earth elements(LREE), large ion lithophile elemental contents(LILE), and relatively depleted Nd isotopic ratios(143Nd/144Nd=0.513139-0.513211), similar to those of normal mid-ocean ridge basalts(NMORB). Comprehensive data on mineral compositions, whole-rock geochemistry, and geochronology demonstrate that a regular variation trend exists in the north-south direction along the Northwest Pacific plate. The 143 Nd/144 Nd values(0.513139-0.513211) and trace-element ratios for whole rocks(Sm/Th=15.35-30.00; Zr/Hf=28.53-35.76; Zr/Y=2.58-3.67; Th/La=0.04-0.06; Th/Y=0.33-0.70), as well as the trace-element ratios(Zr/Hf, La/Yb, Ti/Zr) of clinopyroxenes from Sites 1149 and 801 tholeiites show larger variations compared to those from Site 304 tholeiites(143Nd/144Nd=0.513185-0.513195; Sm/Th=18.19-20.58; Zr/Hf=31.07-33.26; Zr/Y=2.62-3.03; Th/La=0.05-0.06; Th/Y=0.48-0.57). Mineral zoning textures were obvious in tholeiites from Sites 1149 and 801 but were rarely observed in Site 304.These regular features were likely attributed to the differences in the heterogeneity of the magma source,the process of magmatic evolution, the plate-spreading rate, and the effective and ineffective mixing.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.41671011,41871019,41877292,41972212)Research Foundation of Chutian Scholars Program of Hubei Province(Grant No.8210403)Shanxi Key Research and Development program:Feng Cheng(Grant No.2021SF2-03).
文摘Plate subduction leads to complex exhumation processes on continents.The Huangling Massif lies at the northern margin of the South China Block.Whether the Huangling Massif was exhumed as a watershed of the middle reaches of the Paleo-Yangtze River during the Mesozoic remains under debate.We examined the exhumation history of the Huangling Massif based on six granite bedrock samples,using apatite fission track(AFT)and apatite and zircon(U-Th)/He(AHe and ZHe)thermochronology.These samples yielded ages of 157–132 Ma(ZHe),119–106 Ma(AFT),and 114–72 Ma(AHe),respectively.Thermal modeling revealed that three phases of rapid cooling occurred during the Late Jurassic–Early Cretaceous,late Early Cretaceous,and Late Cretaceous.These exhumation processes led to the high topographic relief responsible for the emergence of the Huangling Massif.The integrated of our new data with published sedimentological records suggests that the Huangling Massif might have been the watershed of the middle reaches of the Paleo-Yangtze River since the Cretaceous.At that time,the rivers flowed westward into the Sichuan Basin and eastward into the Jianghan Basin.The subduction of the Pacific Plate beneath the Asian continent in the Mesozoic deeply influenced the geomorphic evolution of the South China Block.
文摘The Trans-North China Belt(TNCB)is a Paleoproterozoic collisional orogen(ca.1.9-1.8 Ga)responsible for the amalgamation of the North China Craton.Detailed field works in Liiliangshan,Hengshan,Wutaishan and Fuping massifs where the belt is well exposed,allow us to draw a new tectonic map and crustal-scale cross sections.The available petrologic,radiometric,geochronologic data are integrated in a geodynamic evolution scheme for this orogen.The Low Grade Mafic Unit(LGMU)is interpreted as an ophiolitic nappe rooted in a suture zone located in the western part of the Lüliangshan.This ophiolitic nappe overthrusts to the SE upon the Orthogneiss-Volcanites Unit(OVU)that consists of a bimodal volcanic-sedimentary series metamorphosed under amphibolite facies conditions intruded by calcalkaline orthogneiss.The OVU is a composite Neoarchean-Paleoproterozoic magmatic arc developed during two stages(ca.2500 and 2100 Ma)upon a continental basement corresponding to the western extension of the Neoarchean Fuping massif The OVU overthrusts to the SE the Fuping massif along the Longquanguan shear zone.This stack of nappes,coeval with an amphibolite facies metamorphism,is dated at ca.1880 Ma.Subsequently,the metamorphic series experienced a widespread migmatization at 1850 Ma and was intruded by post-orogenic plutons dated at 1800 Ma.The weakly to unmetamorphosed Hutuo Supergroup unconformably overlies the metamorphosed and ductilely deformed units(OVU and LGMU),but it is also involved in a second tectonic phase developed in subsurface conditions.These structural features lead us to question the ca.2090 Ma age attributed to the Hutuo supergroup.Moreover,in the Fuping massif several structural and magmatic lines of evidence argue for an earlier orogenic event at ca.2100 Ma that we relate to an older west-directed subduction below the Fuping Block.The Taihangshan Fault might be the location of a possible suture zone between the Fuping Block and an eastern one.A geodynamic model at variance with previous ones,is proposed to account for the formation of the TNCB.In this scheme,three Archean continents,namely from west to east,the Ordos,Fuping and Eastern Blocks are separated by the Lüliang and Taihang Oceans.The closure of the Taihang Ocean at ca.2100 Ma by westward subduction below the Fuping Block accounts for the arc magmatism and the 2100 Ma orogeny.The second collision at 1900-1880 Ma between the Fuping and Ordos blocks is responsible for the main structural metamorphic and magmatic features of the Trans-North China Belt.
基金supported by Chinese National 973 Project no.2009CB825008 and NSFC(40872142,90714007).
文摘The Chinese Tianshan Belt is one of the key regions for the understanding of tectonics of the Central Asian Orogenic Belt(CAOB).An international field excursion and workshop were organized to conduct a common observation and discussion on the tectonic evolution of the Chinese Tianshan.This report summarizes the main achievements,including acknowledged geological features,controversial and remaining scientific problems,and discussion of a tentative geodynamic model.Thus,it is helpful to clarify what has been done in the past,what should be improved and what needs to be done in the future and therefore to better understand the tectonics of the Chinese Tianshan Belt and the CAOB as well.
基金supported by 973 (2012CB416601) and NFSC (41322018) projects
文摘To define a tectonic environment switching from rifting to subduction and their respective duration time are usually largely debated.Such case occurs for the Liaohe rift:whether it went through a long subduction from 2100to 1850 Ma or there were two different events in different
基金financially supported by the National Natural Science Foundation of China(grants 41673038,41521062)the Key Research Program of Frontier Sciences from CAS(QYZDB-SSW-DQC032)the Open Fund Project of State Key Laboratory of Lithospheric Evolution(201707)
文摘The nature(i.e., sub-oceanic, sub-arc or subcontinental) of ophiolitic mantle peridotites from the eastern Neo-Tethyan domain in southern Tibet has been hotly debated. This uncertainty limits our understanding of the history and evolution of the eastern Neo-Tethys Ocean. Here we present petrological, geochemical and Re-Os isotopic data for the mantle peridotites from the Dazhuqu ophiolite in the central segment of the Yarlung Zangbo suture zone, southern Tibet. Samples collected include both spinel lherzolites and spinel harzburgites. The lherzolites have spinel Cr~# [Cr/(Cr + Al), ~ 0.3–0.4] comparable to those of typical abyssal peridotites. In contrast, the harzburgites have spinel Cr~#(~0.3–0.7) overlapping with the ranges of both abyssal and fore-arc peridotites(Day et al., 2017;Parkinson and Pearce, 1998);two samples have spinel Cr~# higher than 0.6, which is probably ascribed to intense melt-rock interactions. Clinopyroxene trace element modeling indicates that the Dazhuqu mantle peridotites have experienced 0–6% garnetfacies melting followed by 10% –18% melting in the spinel stability field. This is similar to the degree of garnet-facies melting inferred for many abyssal peridotites(Hellebrand et al., 2002) and implies deep initial melting(> 85 km), which distinguishes the Dazhuqu mantle peridotites from fore-arc peridotites(commonly <80 km in origin). The Dazhuqu peridotites have unradiogenic 187 Os/188 Os of 0.11836–0.12922, which are commonly lower than the recommended value of primitive upper mantle(PUM)(Meisel et al., 2001). All but one samples yield relatively younger Re depletion ages(TRD = 0.06–0.81 Ga) with respect to the only one sample having an older TRD age of 1.66 Ga. Re-Os isotopes and highly siderophile element(HSE) compositions of the Dazhuqu peridotites are similar to those of abyssal peridotites(Day et al., 2017) and the Oman southern massifs(Hangh?j et al., 2010) but are distinct from noncratonic sub-continental lithospheric mantle(SCLM) xenoliths and sub-arc mantle. We emphasize the similarity between the Dazhuqu and Oman ophiolites, both representing Neo-Tethyan oceanic lithosphere and implying ridge–trench collision.
文摘Ophiolites along the E-W trending Yarlung-Tsangpo Suture(YTS),which separates the Indian plate from the Eurasian plate,have been regarded as relics of the NeoTethyan Ocean.The Xigaze ophiolite in the central YTS
基金supported by MOST(2014CB440801 and 2017YFC0601206)NSFC(41230207,41302167 and 41472208)+2 种基金State Key Laboratory of Earthquake Dynamics(LED2013B03)the China Postdoctoral Council(20100480452,2012T50135)the International Postdoctoral Exchange Fellowship Program
文摘Seventeen new ^40Ar/^39Ar analyses reported for ten Tarim Precambrian basement samples from the Kuluketage area, are applied to reconstruct the regional thermo-tectonic history together with previously published data. Eight samples were taken adjacent to the Xingdi and Xinger faults, major structures in the study area, whereas a further two were sampled at some distance from the faults. 4^40Ar/^39Ar data from the latter record rapid cooling following a Neoproterozoic magmatic/metamorphic event and mild Paleozoic thermal disturbance. Paleozoic ^40Ar/^39Ar ages from the study area, as well as from the Central Tianshan and eastern Southern Tianshan suggest two strong deformational periods at ~390 Ma and ~300 Ma. During the older period, argon isotopic systems were reset/disturbed by high temperature related to arc magmatism resulting from subduction of the South Tianshan paleo-oceanic crust, possibly in combination with reactivation of Precambrian faults. The younger period is characterized by widespread late Carboniferous-early Permian intracontinental deformation, which is related to the final amalgamation of the Central Asian Orogenic Belt. Previously published apatite fission track data attest to a long history of post-collisional cooling, which is attributed to continued propagation of deformation within the Central Asian Orogenic Belt.
基金jointly sponsored by the National Natural Science Foundation of China(Grant Nos.41630320,92062108)the Geology Survey Project(Grant Nos.DD20190012,DD20160082)the Key Laboratory of Deep-Earth Dynamics of Ministry of Natural Resource,Institute of Geology,Chinese Academy of Geological Sciences(Grant No.J1901-16)
文摘The South China block(SC),composed of Cathaysia(CA),Jiangnan Orogenic belt(JNB),and Yangtze block(YB),is one of the most important poly-metallic metallogenic provinces in the world(Zhang et al.,2013),containing of four famous major Mesozoic metallogenic belts,involving the Middle-Lower Yangtze Fe-Cu-Au metallogenic belt(MYMB).
