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| 1 | The age of the base of the Paleoproterozoic Hutuo Group in the Wutai Mountains area, North China Craton: SHRIMP zircon U-Pb dating of basaltic andesite显示文摘Basalt and basaltic andesite metamorphosed at greenschist facies occurs with conglomerate layers at the bottom of the Paleoproterozoic Hutuo Group in the Wutai Mountains area, North China Craton. Detailed geological surveying confirms that these volcanic rocks are conformable within the neighboring sedimentary rocks. The SHRIMP results on basaltic andesite are divided into two groups. In one group the 207Pb/206Pb ages are from 2433 to 2558 Ma, which is consistent with the basement crustal age in Fuping and Wutai areas. In the other group, 13 grains yielded a weighted mean 207Pb/206Pb age of 2140±14 Ma. The latter is interpreted as the eruption age of the basaltic andesite, and gives the age of the base of the Hutuo Group. This result further suggests that the Hutuo Group formed in the middle Paleoproterozoic, not the early Palaeoproterozoic or late Archaean, as thought before, and is related to a 2.2-2.1 Ga rifting event in the Central North China Craton. | DU LiLin YANG ChongHui GUO JingHui WANG Wei REN LiuDong WAN YuSheng GENG YuanSheng | 2010 | Chinese Science Bulletin2010，55，17： | 43 |
| 2 | Depositional chemistry of chert during late Paleozoic from western Guangxi and its implication for the tectonic evolution of the Youjiang Basin显示文摘Continual deep-water sediments from the late Early Devonian to the Late Permian extended in wide areas of western Guangxi.We analyzed the major,trace,and rare earth elements of the Upper Paleozoic cherts in Badu,western Guangxi.High non-terrigenous SiO2 contents(Sinon-ter/Sibulk(%)> 80%) and pure chert components(> 70%) indicate a large extent of silicification in the Upper Paleozoic cherts,except for the Upper Devonian-Lower Carboniferous Luzhai Formation cherts,which have lower non-terrigenous SiO2 contents(avg.71.8%) and pure chert components(40%-70%).The Al/(Al+Fe+Mn) ratios and Feter/Febulk(%) values of samples from the lowest horizon of the Pingen Formation are 0.05-0.26,13.1%-14.5%,respectively,indicating hydrothermal origins.All other samples show high Al/(Al+Fe+Mn) ratios(0.39-0.81) and high Feter/Febulk(%) values(23.1%-186.8%),indicating non-hydrothermal origins.The Pingen Formation and Liujiang Formation cherts show slightly-moderately negative Ce anomalies(0.71±0.07,0.81±0.08,respectively) and higher Y/Ho ratios(33.49±1.27,36.10±2.05,respectively) than PAAS.This suggests that these cherts were deposited in the open marine basin,rather than in the intracontinental rift basin as previously assumed.The Luzhai Formation cherts may be deposited near the seamount or seafloor plateaus with no negative Ce anomalies(1.09±0.07) and no significant Y-Ho fractionation(Y/Ho=28.60±1.25).The Nandan Formation and Sidazhai Formation cherts were deposited in the open-ocean basin with moderately negative Ce anomalies(0.67±0.08,0.73±0.11,respectively) and high Y/Ho ratios(36.01±1.00,32.00±2.25,respectively).On the basis of our studies about cherts,we conclude that the Youjiang Basin originated as part of the Paleo-Tethys that controlled the depositional environments of cherts during late Paleozoic.The rift of the Youjiang Basin had occurred at least since the Early-Middle Devonian.The basin had a trend of evolving into an open-ocean basin during the Early-Middle Permian. | HUANG Hu DU YuanSheng HUANG ZhiQiang YANG JiangHai HUANG HongWei XIE ChunXia HU LiSha | 2013 | Science China Earth Sciences2013，56，3： | 20 |
| 3 | Soft-sediment Deformation Structures Related to Earthquake from the Devonian of the Eastern North Qilian Mts.and Its Tectonic Significance显示文摘摘要:在北方 Qilian orogenic 带和 Hexi 走廊的泥盆纪开发了在北方中国板和 Qaidam microplate 之间的碰撞引起的低岬盆的以后的舞台的陆上的 molasse。低岬盆触发了强烈地震,并且形成了 seismites 和地震相关的软沉积的变丑。在东方北方 Qilian 山的泥盆纪的软沉积的变丑结构由 seismo 裂缝组成,沙岩女同性恋, syn-depositional 差错, microfolds (微弄皱迭合) ,使流体化的静脉,负担演员组,火焰结构,枕头结构和 brecciation。seismo 裂缝, syn-depositional 差错和 microfolds 是地震的摆动直接形成的裂缝,差错和褶层。地震女同性恋由沉积灌输进地震裂缝形成了。使流体化的静脉被灌输进使流体化的沙的 seismo 裂缝做。负担演员组,火焰结构和枕头结构被下沉并且灌输形成沿着在沙、泥泞的床之间的脸从地震的摆动引起了。brecciation 源于地震的摆动并且沉积的层裂开。在泥盆纪的 seismites 和软沉积的变丑在造山运动期间触发了与构造活动有关的地震并且北方 Qilian 山高举。 | DU Yuansheng XU Yajun YANG Jianghai | 2008 | Acta Geologica Sinica(English Edition)2008，82，6： | 13 |
| 4 | Paleoenvironmental records from the northern South China Sea since the Last Glacial Maximum显示文摘Core ZHS-176 contains the paleoenvironmental records from the northern South China Sea (NSCS) since the Last Glacial Maximum (LGM). A coupled approach based on clay mineral assemblages, planktonic foraminiferal oxygen and carbon isotopes, and calcium carbonate content is used to trace the sources of the fine-grained sediment and to investigate the paleoenviornmental evolution in this area. Clay mineral assemblages are dominated by illite (average about 39%) and chlorite (about 27%), which comes mainly from Taiwan and the East China Sea. Kaolinite, which accounts for about 13%, comes mainly from the Zhujiang (Pearl) River, and Luzon Island is the main source for smectite (about 21%). The planktonic foraminiferal oxygen isotopic oscillations during the last glacial period are coeval with climate variations recorded in the Greenland ice core and Western Pacific sediment. These variations include the LGM, Heinrich event 1, Bφlling-Allerφd (B/A), and Younger Dryas. For the Holocene, three periods of strong precipitation (S1-S3) and three periods of weak precipitation (W1-W3) are identified. The oxygen isotopic record exhibits corre-lation with climate records from distant regions, including the high-latitude Northern Hemisphere, providing evidence for global tele-connection among regional climate. A brief, negative planktonic foraminiferal carbon isotopic excursion during B/A reflects increased methane released from marine gas hydrate due to the rapid warming of the water. By comparing calcium carbonate content curves of the core ZHS-176 with these of other five boreholes lying above the lysocline, a remarkable low calcium carbonate event is found during the early Holocene in NSCS. | GE Qian CHU Fengyou XUE Zuo LIU J Paul DU Yuansheng FANG Yinxia | 2010 | Acta Oceanologica Sinica2010，29，3： | 13 |
| 5 | Silurian Seismites in Hanxia,Yumen,North Qilian Mountains,and Their Tectonic Significance显示文摘The Caledonian orogenic belt of the North Qilian Mountains is anintensely active structure belt. In the process of the Late Caledonian syn-orogeny, the North Qilian-Hexi Corridor area was situated on the tectonic background of a syn-orogenic basin. In response to the orogenic process of the North Qilian Mountains, typical earthquake event deposits-seismites of the Silurian were widely distributed around Hanxia of Yumen City, the Liyuan River of Sunan County and Biandukou of Minle County. In the Hanxia area, where seismites are typically developed, clastic deposits of tidal-flat facies are the background deposits of the Hanxia Formation. The earthquake event deposits are characterized by sandy mudstone veins, synsedimentary microfractures, micro-corrugated laminations and earthquake breccias, which in turn constitute complex seismites, featuring seismic corrugation, shattering and liquefied sandy mudstone veins, auto clastic breccias and intraclastic parabreccias. The seismites and tidal flat deposits formed typical sequences of earthquake event deposits. | DU Yuansheng, GONG Shuyun, HAN Xin, WANG Jiasheng, GU Songzhuand LIN Wenjiao Faculty of Earth Sciences, China University of Geosciences, Wuhan 430074, Hubei | 2001 | Acta Geologica Sinica(English Edition)2001，75，4： | 11 |
| 6 | Provenance of the Paleoproterozoic Hutuo Group basal conglomerates and Neoarchean crustal growth in the Wutai Mountains,North China Craton:Evidence from granite and quartzite pebble zircon U-Pb ages and Hf isotopes显示文摘Zircon U-Pb ages(SHRIMP and LA-ICPMS) and Lu-Hf isotope data(LA-ICPMS) are presented for two granite and two quartzite pebbles from the basal conglomerates of the Sijizhuang Formation in the Hutuo Group from the Wutai Mountains area in the North China Craton.These two granite pebbles give zircon 207 Pb/206 Pb ages of 2513±8 Ma and 2527±8 Ma respectively,which are consistent with the emplacement ages of the Wangjiahui grey granite and Guangmingsi or Shifo granite in the Wutai Mountains.Detrital zircons from those two quartzite pebbles are mostly 2550-2490 Ma old with lesser number of 2800-2550 Ma grains,which is similar to the ages of detrital zircons from quartzites in the Gaofan Subgroup of the Neoarchean Wutai Group.Thus,the pebbles in the Hutuo Group basal conglomerates were derived locally from Wutai Mountains Neoarchean sources.Zircons from the Sijizhuang Formation conglomerate granite and quartzite pebbles mostly have positive ε Hf(t) values,a minority with ε Hf(t) values like model depleted mantle(DM) of the same age,but with most showing DM model ages 200-100 Ma.This indicates that most of the source materials were derived from the mantle within the previous 200 million years,whereas some are derived from 2550-2510 Ma juvenile crustal additions.This additional evidence suggests that in the North China Craton there was important initial polycyclic crustal formation and cratonization in the late Neoarchaean,prior to superimposed Palaeoproterozoic orogenic cycles. | DU LiLin YANG ChongHui WANG Wei REN LiuDong WAN YuSheng SONG HuiXia GAO LinZhi GENG YuanSheng HOU KeJun | 2012 | Science China Earth Sciences2012，55，11： | 8 |
| 7 | Lower Carboniferous carbon isotope stratigraphy in South China: Implications for the Late Paleozoic glaciation显示文摘Studies on carbon isotopes of bulk carbonates from Longan and Baping sections of Lower Carboniferous in Guangxi of China show that the stable carbon isotope compositions in carbonate rocks of the isolated platform and deep slope facies were resistant to the influence of early meteoric diagenesis and late burial diagenesis. Three major positive carbon isotope excursions have been recognized in Lower Carboniferous in South China. The first major positive δ13C shift of 4.19‰ occurred in the middle part of Siphonodella isosticha-upper Siphonodella crenulata zone (Tournaisian); the second with an amplitude of 4.65‰ occurred near the Tournaisian/Visean boundary; and the third of 2.23‰ in the lower part of Gnathodus bollandensis zone. The three positive shifts of δ13C can be correlated with global carbon isotope excursions and are consistent with the fall in global sea level, indicating that abundant organic carbon burial, lowering of atmospheric CO2, and glaciation may have occurred during these time intervals. | QIE WenKun ZHANG XiongHua DU YuanSheng ZHANG Yang | 2011 | Science China Earth Sciences2011，54，1： | 8 |
| 8 | Sedimentary geochemistry and provenance of the Lower and Middle Devonian Laojunshan Formation,the North Qilian Orogenic Belt显示文摘The Laojunshan Formation is a suite of molasse formed during the rapid uplift of the North Qilian Orogenic Belt (NQOB). Forty-one samples of sandstone have been collected from the Sunan and Minle sections in the western sector and the Gulang and Jingyuan sections in the eastern sector of the NQOB belt. Geochemical analyses of those samples indicated: 1) The MgO+Fe2O3T and Al2O3/SiO2 values are higher, and K2O/Na2O ratios are lower in the western sector than those in the eastern sector. 2) All of them are depleted in Nb and Ta elements. The samples from the western sector are depleted in Rb element and enriched with Sc, Co, Ni, V, and Cr elements in the Upper Crust-normalized patterns. However, those from the eastern sector are depleted in Sr without enrichments of Sc, Co, Ni, V, and Cr. 3) All of the samples display a right-inclined REE pattern af- ter Chondrite-normalized REE pattern. But LaN/YbN and Eu/Eu* ratios of the samples from the western sector are lower than those of the samples from the eastern sector. These geochemical characteristics suggest the prominent input of mafic clast with minor granitic rocks into the Sunan area, felsic clast into the Gulang and Jingyuan area, and both mafic and felsic clast into the Minle area. The angular shapes of gravels imply that these ill-sorted sediments were deposited near their sources without recy- cling. Geochemical features above also demonstrated that no major chemical weathering occurred for the western provenance, but deposits in the eastern sector resulted from low or middle degree chemical weathering. Evidences combining tectonic discriminations and comparisons with potential provenances revealed that sediments in the Sunan area were derived mainly from the North Qilian Continental arc, whereas sediments in the Minle, Gulang, and Jingyuan areas were derived not only from the North Qilian Continental arc but also from the basement of the Middle Qilian block. Integrated with the characteristics of development of Silurian and Devonian, these imply that the orogeny of NQOB is diachronous in the trending direction due to the oblique collision. | XU YaJun DU YuanSheng YANG JiangHai HUANG Hu | 2010 | Science China Earth Sciences2010，53，3： | 7 |
| 9 | Devonian Frasnian-Famennian transitional event deposits of Guangxi, South China and their possible tsunami origin显示文摘A suite of event deposits, isochronous and interrelated in origin, occurs widely near the Frasnian- Famennian boundary in Guangxi, South China. It is mainly distributed in the facies areas of the platform-margin slope and inter-platform rift-trough. The rudstone or calcirudite occur in the Liujing section of Hengxian and Luoxiu and Baqi sections of Xiangzhou in the facies area of platform-margin slope. The turbidites are observed in the sections of Yangdi and Baisha of Guilin, Du'an of Debao, Nandong and Sanli of Wuxuan, Xiangtian, Ma'anshan of Xiangzhou, Nayi of Chongzuo, Yunpan of Shanglin in the facies area of inter-platform rift-trough. The massive homogenites occur in sections of Mangchang, Luofu and Road from Nandan to Tian'e and Ma'anshan etc in the facies area of inter-platform rift-trough. Herein event deposits can be correlated in stratohorizon to the turbidite in the bottom of the Lower triangularis Zone in Hony railroad cut of Belgium, Devils Gate of Nevada, USA, Atrous of Morocco, South Urals and Fore-Kolyma of northeastern Siberia of Russia, and erosional discontinuities and brecciation in the Frasnian-Famennian boundary in South Polish-Moravian shelf. The event deposits could be caused by a violent tsunami related to bolide impacts into ocean. | DU YuanSheng GONG YiMing ZENG XiongWei HUANG HongWei YANG JiangHai ZHANG Zhe HUANG ZhiQiang | 2008 | Science China Earth Sciences2008，51，11： | 6 |
| 10 | Growth of a polymetallic nodule from northwestern continental margin of the South China Sea and its response to changes in paleoceanographical environment of the late Cenozoic显示文摘In the northern South China Sea,the accumulation of enormous quantities of terrigenous sediment during Cenozoic rendered well-developed polymetallic nodules very rare.In this study,we analyzed a polymetallic nodule from the northwestern continental margin of the South China Sea using microscopic mineralogical observation,electron probes,X-ray diffraction(XRD),ICP-MS,and Be isotope dating.We found the nodule's shell layers rich in different types of microstructures,including columnar,laminar,stack-like,petal-like,and porphyritic structures.The major mineral components of the nodule are MnO2.Unlike nodules from the eastern Pacific basin,this nodule has high contents in Fe,Si,Al,and REEs but low contents in Mn,Cu,Co,and Ni.The Mn/Fe ratio is also low and the average REEs content is 1370.4 ppm.There is a strong positive anomaly of Ce;and the Be(beryllium) isotope dating shows the initial time of growth of the nodule to be about 3.29 Ma.The inner compact layer formed from 3.29 Ma to about 1.83 Ma.The laminar and stack-like structures and the low contents of the terrigenous elements such as Fe,Si,REE,and Al indicate the paleoceanographical environment with weak undersea currents and favorable oxidizing conditions.From 1.83 Ma to 0.73 Ma,the growth rate of the nodule increased by about 3%;the microstructures formed during this period are stack-like and columnar.The contents of Si and Al are increased by nearly 10%,indicating an increase of terrigenous sediment input in the northern South China Sea.The content of Ce is decreased by about 16%,indicating a significant weakening of the oxidizing conditions at the seabed.From 0.73 Ma to 0.69 Ma,the growth rate of the nodule rapidly rose up to 8.27 times that of the nodule's average growth rate,and the contents of Fe,Al,and REEs in the layer also increased,forming a loose layer characterized by oolitic,granular,porphyritic,and petal-like structures,indicating the paleoceanographical environment with a high sedimemtation rate and abundant supply of terrigenous sediment in the northern South China Sea.From 0.69 Ma to 0.22 Ma,the growth rate of the nodule suddenly slowed and the outer compact layer formed.Contents of Fe,Si,REE,Al,Mn,Cu,Co,and Ni in this layer were significantly lower than in other layers.The main structures of the layer are laminar and fissure filling structures.These reflect the paleoceanographical environment with stable undersea currents,poor oxidizing conditions,and other conditions not conducive to nodule growth.The growth process of nodule S04-1DG-1 was found to respond sensitively to the changes of the paleoceanographical environment of the northern South China Sea during the late Cenozoic. | ZHANG ZhenGuo DU YuanSheng WU ChangHang FANG NianQiao YANG ShengXiong LIU Jian SONG ChengBing | 2013 | Science China Earth Sciences2013，56，3： | 5 |
| 11 | New Zircon U-Pb Age of the Babu Ophiolites in Southeast Yunnan,China and Constrains of Plate Subduction Time显示文摘Objective The Babu ophiolite in Malipo County of southeastern Yunnan is interpreted as remanant ocean crust and represents a possible branch of Paleo-Tethyan Ocean in South China.It consists mainly of mafic and ultramafic rocks.These rocks are very important to understand the evolution of the Paleo-Tethyan Ocean.However,the Babu ophiolite is still disputed and the mafic and ultramafic rocks have been inferred to be part of the Emeishan large igneous province(LIP)by some researchers.In this paper,we present zircon U-Pb data on the metabasalts in | HUANG Hu DU Yuansheng YANG Jianghai YU Wenchao | 2017 | Acta Geologica Sinica(English Edition)2017，91，3： | 4 |
| 12 | Geochemistry of the Late Paleozoic cherts in the Youjiang Basin:Implications for the basin evolution显示文摘We analyzed the major and rare earth element compositions of siliceous deposits from the Upper Devonian Liujiang Formation,Lower Carboniferous Luzhai Formation,Lower-Middle Permian Sidazhai Formation and Tapi Formation,which are widely distributed as bedded cherts in the interplatform basinal successions of the Youjiang Basin.The Liujiang Formation and Luzhai Formation cherts generally have high Al/(Al+Fe+Mn) values(0.38-0.94) and are non-hydrothermal cherts.These cherts are generally characterized by moderately negative Ce anomalies and high Y/Ho values relatived to PAAS,indicating that the Youjiang Basin might have evolved into an open rift basin during the Late Devonian-Early Carboniferous.The Sidazhai Formation cherts from Ziyun generally have high Al/(Al+Fe+Mn) values(0.60-0.78),suggesting negligible contribution from a hydrothermal component.The Sidazhai Formation cherts from Hechi and the Tapi Formation cherts from Malipo generally have low Al/(Al+Fe+Mn) values(0.09-0.41),indicating an intense hydrothermal input.Relatived to the Sidazhai Formation cherts,the Tapi Formation cherts have higher Ce/Ce*values(0.68±0.19) and lower Y/Ho values(41.83±13.27),which may be affected by the terrigenous input from the Vietnam Block.The Sidazhai Formation cherts from Ziyun and Hechi exhibit negative Ce anomalies(0.43±0.12,0.33±0.17,respectively) with high Y/Ho values(57.44±16.20,46.02±4.27,respectively),resembling the geochemical characteristics of open-ocean basin cherts.These cherts were deposited on a passive continental margin adjacent to the Babu branch ocean,which may have contributed to upwelling.Detailed spatial studies on geochemical characteristics of the Late Paleozoic cherts can unravel the evolution of the Youjiang Basin. | Huang Hu Du Yuansheng Yang Jianghai Huang Hongwei Tao Ping Huang Zhiqiang Yu Wenchao Guo Hua | 2013 | Journal of Palaeogeography2013，2，4： | 4 |
| 13 | Seismic geomorphology of buried channel systems in the western South Huanghai Sea:retrodiction for paleo-environments显示文摘Quantitative morphologic analysis of shallowly buried,dendritic channel systems in the continental shelf off the abandoned Huanghe River (Yellow River) mouth has been made based on interpretation of high resolution seismic profiles,with the attempt to estimate the paleo-hydrologic parameters when the incised-channels formed,then assess the paleoenvironment.The results indicate that the buried channel systems were formed about 44 cal ka BP when the shelf was subaerially exposed and subsequently drowned and filled during the Holocene transgression with the sea level rise continuously.The study area has experienced the processes from fluvial and estuarine to fully marine. | KONG Xianghuai LIU Jian DU Yuansheng WEN Chun XU Gang | 2011 | Acta Oceanologica Sinica2011，30，1： | 3 |
| 14 | Devonian Sequence Stratigraphy and Sea Level Change Cycles in South China显示文摘The Devonian is well developed in South China and has drawn a great attention from the geologists both at domestic and abroad. On the basis of study on the sequence stratigraphy in more than 10 sections in Guizhou, Guangxi, Longmenshan and Southern Qinling within South China we have identified 21 sequences and T-R cycles that correspond to third-order sea level changes. These sea level change cycles were controlled by autorhythm(Pragian,Eifelian), allorhythm(Lochkovian,Emsian,Givetian) and coupling rhythm mechanisms (frasian, Famennian and F-F boundary). | Du Yuansheng Gong Yiming (Faculty of Earth Sciences, China University of Geosciences, Wuhan 430074) Wu Yi (Guangxi Institute of Geology, Nanning 530023) Liu Benpei Feng Qinglai (Faculty of Earth Sciences, China University of Geosciences, Wuhan 430074) | 1996 | Journal of Earth Science1996，15，1： | 3 |
| 15 | Provenance of Lower Carboniferous Bauxite Deposits in Northern Guizhou,China:Constraints from Geochemistry and Detrital Zircon U-Pb Ages显示文摘The Lower Carboniferous Jiujialu Formation bauxite deposits of northern Guizhou Province,China,are a Kazakhstan subtype of karst bauxite deposits.The provenance of the Jiujialu Formation has long been debated,with uncertainty about the formation of the bauxite deposits.Here we report new geochemical data that indicate the affinity between the Lower-Middle Ordovician clastic rocks and argillaceous dolostones and the overlying Carboniferous bauxite deposits,all of which are characterized by high Al_(2)0_(3),K2_(O),and∑REE contents,flat post-Archean Australian shale(PAAS)-normalized REE patterns,and uniform immobile element ratios(TiO2/Al_(2)0_(3),Nb/TiO2,and Zr/TiO2).Their similar detrital zircon age distributions further indicate the link between the bauxite deposits and the clastic rocks and argillaceous dolostones.Zircon age spectra of clastic rocks of the Lower Silurian Hanchiatien Formation in northern Guizhou match those of the bauxite deposits,with a maximum age peak at-980 Ma and other secondary age peaks,suggesting these clastic rocks may represent the provenance of the bauxite deposits.The youngest detrital zircons(-445 Ma)occur only in the bauxite deposits and are probably sourced from K-bentonite beds of the Ordovician-Silurian tran-sition.Our analyses indicate that the source materials of the bauxite deposits in the Jiujialu Formation are of mixed provenance:Lower-Middle Ordovician aluminosilicate rocks and argillaceous dolostones of the underlying strata,and Lower Silurian clastic rocks and K-bentonite from adjacent areas.A comparison of Early Carboniferous bauxitic provenances in northern and central Guizhou indicates that paleotopography was the major factor controlling the provenance of these bauxite deposits. | Guolin Xiong Wenchao Yu Yuansheng Du Shenfu Weng Dawei Pang Xusheng Deng Jintao Zhou | 2021 | Journal of Earth Science2021，32，1： | 3 |
| 16 | Geochemical significance of the Paleogene soda-deposits bearing strata in Biyang Depression,Henan Province显示文摘The Biyang Depression,lying in the eastern Nanxiang Basin,has a dustpan-shape with faults developed to the southwest and southeast.The Paleogene Hetaoyuan Formation in this depression hosts one of the oldest soda-deposits,the Anpeng deposit.These sodium carbonate-bearing strata consist of lutites,muddy dolomites,and bedded soda-deposits,which are dominated by nahcolite with little trona,mirabilite,and halite.In the top Unit 3 and lower Unit 2 of Hetaoyuan Formation where the sodium carbonates are concentrated,dolomitic shale,muddy carbonate,and sodium carbonate can be separated based on their distinct Al2O3,Ti O2,Na2O,Mg O+Ca O,and LOI(loss on ignition)contents.By using Na2O/(Mg O+Ca O)ratio as an indicator for the relative concentration of Na carbonates to Mg-Ca carbonates,the muddy dolomites can be classified into two groups.One group with Na2O/(Mg O+Ca O)<0.6 exhibits a positive correlation between this ratio and Al2O3+Ti O2 content,an proxy for terrigenous clastic input and the other group with Na2O/(Mg O+Ca O)>0.6 presents a negative correlation.As the clastic proportion decreases,the former indicates that it tends to form pure Mg-Ca carbonates reflecting evaporation less than or equal to replenishment for the lake water in a relative humid climate,and the latter reveals a trend to form sodium carbonates with lake water’s evaporation more than replenishment in a relatively dry climate.From muddy dolomite to sodium carbonate samples,with Na2O/(Mg O+Ca O)ratio increasing,the Al normalized Zr,Ti,La,K,Rb,and Ba tend to be enriched and the post-Archean Average Shale(PAAS)normalized positive Eu anomaly becomes more obvious.Integrated with the high B contents and the report of searlesite in the bedded sodium carbonates and the regional extensional tectonic regime,the above geochemical characteristics were interpreted to signify hydrothermal contribution to forming these soda-deposits through the deep fault systems of basin margins. | YANG JiangHai YI ChengLong DU YuanSheng ZHANG ZongHeng YAN JiaXin | 2015 | Science China Earth Sciences2015，58，1： | 3 |
| 17 | Detrital zircon of 4.1 Ga in South China显示文摘One hadean zircon from the Cambrian sandstone in the southern part of South China has a U-Pb age of 4107±29 Ma with ε Hf(t) value similar to that of the homochronous depleted mantle and Hf model age of 4102±21 Ma.This demonstrates the existence of hadean crustal remnant in South China.A close match between the U-Pb age and Hf model age with the highly position ε Hf(t) value indicates the growth and immediate reworking of juvenile crust from the depleted mantle at ca 4.1 Ga.The prominent 'Pan-African' and Grenville zircons derived from the exotic sources were also found in the sample,which indicates a linking between South China and Gondwana in the Cambrian period.The southern part of South China has complex histories of crustal growth and tectonic evolution. | XU YaJun DU YuanSheng HUANG HongWei HUANG ZhiQiang HU LiSha ZHU YanHui YU WenChao | 2012 | Chinese Science Bulletin2012，57，33： | 2 |
| 18 | Trace and rare earth elemental geochemistry of carbonate succession in the Middle Gaoyuzhuang Formation,Pingquan Section:Implications for Early Mesoproterozoic ocean redox conditions显示文摘The concentrations of redox-sensitive trace elements,such as uranium(U),vanadium(V),molybdenum(Mo),cobalt(Co),chromium(Cr) and rare earth elements(REE+Y) were determined in a given carbonate succession in the Gaoyuzhuang Formation(~1.56 Ga),which spans depths from outer shelf to intertidal,to explore the Early Mesoproterozoic ocean redox conditions.The values of the Zr-normalized redox-sensitive trace element concentrations and some relevant ratios show obvious changes from bottom to top in the succession.Samples from the outer shelf setting(M1 interval) demonstrate significantly enhanced values in Zr-normalized redox-sensitive trace element concentrations and relevant ratios(the peaks of Mo/U,V/Cr and Ni/Co ratios larger than 8,4.25,and 7,respectively).Authigenic framboidal pyrites were also found within oncolite-like carbonate concretions and surrounding host rocks in this interval.These all indicate a euxinic state in the outer shelf environment.Less enrichment of Zr-normalized redox-sensitive elemental abundances and a mild decrease in the values of geochemical ratios were present in the inner shelf environment(M2 interval)(the V/Cr and Ni/Co ratios fall into a range of 2.5 4.25 and 4 5,respectively),suggesting dysoxic conditions dominant in the inner shelf setting.Samples from the shallower subtidal and intertidal settings(M3 and M4 intervals) are mostly invariable with much lower values of Zr-normalized redox-sensitive elements and relevant ratios,with the V/Cr and Ni/Co ratios typically near or less than 2 and 5 respectively,indicative of oxic conditions in the high energy subtidal/intertidal zones.A remarkable negative Ce anomaly exhibited in the shale-normalized REE+Y diagram in the M4 interval may provide evidence in support of the hypothesis.Taken together,our results suggest a relatively shallow chemocline in the Early Mesoproterozoic ocean:the transitions between euxinic,dysoxic and oxic may occur in quiet-water outer shelf and highenergy subtidal zone,respectively.The presence of euxinic ocean bottom waters is compatible with low concentrations of seawater sulfate and reduced levels of atmospheric oxygen during this period.The extreme environmental conditions induced by these anoxic oceans could have been responsible for the delayed oxygenation of the biosphere and hindered the evolution of multicellular life. | Guo Hua Du Yuansheng Zhou Lian Yang Jianghai Huang Hu | 2013 | Journal of Palaeogeography2013，2，2： | 2 |
| 19 | Ca. 1.7 Ga Magmatism on Southwestern Margin of the Yangtze Block: Response to the Breakup of Columbia显示文摘This paper presents some data of the Jiaopingdu gabbro and Caiyuanzi granite at the southwestern margin of the Yangtze Block,on the geochemical compositions,zircon LA-ICP-MS U-Pb ages and Hf isotopic data.The Jiaopingdu gabbro gives the age of 1721±5 Ma,the Caiyuanzi granite 1732±6 Ma and 1735±4 Ma,and the Wenjiacun porphyry granite 1713±4 Ma,suggesting nearly contemporaneous formation time of the gabbro and granite.The bimodal feature is demonstrated by the gabbro Si O2 content of 44.64-46.87 wt%and granite 73.81-77.03 wt%.In addition,the granite has high content of Si O2 and Na2 O+K2 O,low content of Al2 O3 and Ca O,enriched in REEs(except Eu)and Zr,Nb,Ga and Y,depleted in Sr,implying it belongs to A-type granite geochemistry and origin of within-plate environment.The zirconε(Hf)(t)of the granite and gabbro is at the range of 2-6,which is near the 2.0 Ga evolution line of the crust,implying the parent magma of the gabbro being derived from the depleted mantle and a small amount of crustal material,and the parent magma of the granite from partial melting of the juvenile crust and some ancient crustal material at the same time.Compared with 1.8-1.7 Ga magmatism during breakup of other cratons in the world,we can deduce that the Columbia has initially broken since ca.1.8 Ga,and some continental marginal or intra-continental rifts occurred at ca.1.73 Ga. | GENG Yuansheng DU Lilin KUANG Hongwei LIU Yongqing | 2020 | Acta Geologica Sinica(English Edition)2020，94，6： | 1 |
| 20 | Detrital zircon record of continental collision: Assembly of the Qilian Orogen, China显示文摘 | Xu Yajun Du Yuansheng Cawood P A | 2010 | Sedimentary Geology2010，230，： | 1 |
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