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Science China Earth Sciences 2015年第8期58卷 1305-1319,1-5页

作者： WANG LiNing JI JianQing SUN DongXia XU QinQin han baofu Research Institute of Petroleum Exploration and Development Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space Sciences Peking University

The extreme modern elevation of the Tianshan Mountains reflects the Cenozoic deformation.Apatite Fission Track(AFT)chronometry is widely used to study the latest cooling stages caused by tectonic process or by exhumation in the uppermost crust.However,uncertainties remain over timing constraints on thermal history of the Tianshan Mountains since the Cenozoic though a great mount of dating work had been done in this area.To address this issue,modern river sands from the drainage basin on the piedmont of the Tianshan Mountains were sampled to integrate regional information.Single grains were dated with the AFT method,and then different grain-age components were identified to provide thermochronological constraints of their sources.Combined with discussion of previous dataset,our results show the multi-staged rapid cooling cluster at 46–32,25–24,19–13,8–6,and^3 Ma,respectively.We interpreted these cooling events as a result of interplays between the Cenozoic tectonic uplift of the mountains and regional climate change.

关键词：磷灰石裂变径迹天山山脉时间顺序快速降温轨迹分析多段河流区域气候变化

Petrogenesis and Tectonic Implications of Middle Ordovician Ocean Island Basalts from the Chagantaolegai Ophiolitic Mélange in Junggar,NW China

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Acta Geologica Sinica(English Edition) 2021年第4期95卷 1099-1111页

作者： CHEN Jiafu LI Rongyan MA Haitao han baofu LIU Junlai Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines Department of GeologyNortheastern UniversityShenyang 110819China Department of Earth Planetaryand Space SciencesUniversity of CaliforniaLos Angeles 90095USA Ministry of Education Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking UniversityBeijing 100871China State Key Laboratory of Geological Process and Mineral Resources School of Earth Sciences and ResourcesChina University of Geosciences(Beijing)Beijing 100083China

Seamount accretion is one of the most significant accretionary orogenic processes in the Central Asian Orogenic Belt,but there are few paleo-seamounts reported from and debate on the tectonic evolution of the Junggar Ocean still exists.In this study,we present geochronological,mineralogical,geochemical and isotopic data for basalts from the Chagantaolegai ophiolitic mélanges in Junggar.Zircon U-Pb dating on one basalt yielded a weighted mean^(206)Pb/^(238)U age of 469±7 Ma,which suggests that it formed in the Middle Ordovician.All rock samples belong to alkaline basalt and show similar geochemical characteristics,displaying high TiO_(2)(~3 wt%),(La/Yb)N(17.6–19.0),ΣREE(232–289 ppm)and enrichment in Nb and Ta,which implies an ocean island basalt(OIB)affinity.Based upon positiveεN d(t)(+4.16 to+4.23),ΔNb(0.20–0.22)and low initial^(87)Sr/^(86)Sr(0.70425 to 0.70452)and Zr/Nb(3.35–3.57),we suggest that the Chagantaolegai OIB samples were likely derived from a fertile mantle source related to plume.The OIB rock assemblage,chert and marble in the southern part of the Chagantaolegai ophiolitic mélange indicates that a Middle Ordovician seamount was accreted to the Boshchekul-Chingiz arc due to the northward subduction of the Junggar-Balkhash Ocean.

关键词： ocean island basalt seamount Middle Ordovician CAOB West Junggar

Platinum-group element geochemistry of Cenozoic basalts from the North China Craton: Implications for mantle heterogeneity

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Science China Earth Sciences 2015年第6期58卷 881-895页

作者： ZhanG WenHui ZhanG HongFu SUN YaLi FAN WeiMing han baofu TANG YanJie School of Zijin Mining Fuzhou University State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Guangzhou Institute of Geochemistry Chinese Academy of Sciences Department of Earth Sciences Peking University

42 新生代(主要中新世) 从北方中国 Craton 的 Jining， Chifeng， Fansi， Xiyang，和 Zuoquan 区域的暗岩样品(NCC 暗岩此后) 为铂组元素(PGE，包括的 O，红外， Ru， Rh，磅，和 Pd ) 被分析。他们中的大多数是碱的暗岩和 tholeiite... 详细信息

42 新生代(主要中新世) 从北方中国 Craton 的 Jining， Chifeng， Fansi， Xiyang，和 Zuoquan 区域的暗岩样品(NCC 暗岩此后) 为铂组元素(PGE，包括的 O，红外， Ru， Rh，磅，和 Pd ) 被分析。他们中的大多数是碱的暗岩和 tholeiites，所有几乎不他们显示很少外壳的污染。NCC 暗岩的全部的 PGE 内容从 0.1 ～ 0.9 ppb 变化，原始披风的比那些低的大部分 23.5 珍视 ppb。这些暗岩的原始使披风正常化的 PGE 模式定义积极斜坡和 Pd/Ir 比率从 1.2 ～ 25 变化。以 PGE 内容和 Pd/Ir 比率，他们相当类似于海中央山脉暗岩。在 PGE 之间没有明显的否定关联，显示在 magmatic 期间的橄榄石，辉石，或硫化物的部分结晶化处理对在 NCC 暗岩的 MgO， Ni，和 Cu 不能是为观察 PGE 变化的控制因素。NCC 暗岩的观察 Pd/Ir 变化要求异构的披风采购的 non-chondritic 的参与。基于 Sr-Nd-Pb-Hf 同位素的 systematics 和不兼容元素的签名，一混合部分在岩流圈的顶从 asthenospheric 橄榄岩和围住的披风 eclogites 融化为这些 NCC 暗岩的起源被建议。eclogites 的透镜从再循环的大陆人外壳的 upwelling 被导出在期间向西从 600 km 断绝地区的和平的板的 subduction。这些暗岩的 PGE 地球化学提供独立证据支持这个结论和观察 Pd/Ir 变化可以在拍的 peridotitic 的比例反映变化， eclogitic 融化。

关键词：铂族元素地球化学拉斑玄武岩中国北方克拉通新生代地幔异质性洋中脊玄武岩

额尔齐斯杂岩碎屑锆石U-Pb年龄及其对阿尔泰和东准噶尔地体拼合时限的制约

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地质通报 2024年第6期43卷 1032-1046页

作者：李昂徐严韩宝福廖闻造山带与地壳演化教育部重点实验室北京大学地球与空间科学学院北京100871

额尔齐斯杂岩位于新疆北部的阿尔泰和东准噶尔地体之间,经历了强烈的变质变形作用,记录了2个地体的构造拼合事件。为约束阿尔泰和东准噶尔地体的拼合时限,通过碎屑锆石U-Pb年龄分析探讨沉积物源。从变碎屑岩样品中获得最年轻的碎屑锆石... 详细信息

额尔齐斯杂岩位于新疆北部的阿尔泰和东准噶尔地体之间,经历了强烈的变质变形作用,记录了2个地体的构造拼合事件。为约束阿尔泰和东准噶尔地体的拼合时限,通过碎屑锆石U-Pb年龄分析探讨沉积物源。从变碎屑岩样品中获得最年轻的碎屑锆石年龄为354 Ma。在综合分析新的和已发表的碎屑锆石和区域构造年代学资料后,认为在额尔齐斯杂岩中,除同时以阿尔泰和东准噶尔地体为物源和以东准噶尔地体为单一物源的2类晚石炭世同碰撞沉积外,还可能包括较早以阿尔泰地体为单一物源的被动陆缘沉积,表明额尔齐斯杂岩形成时,阿尔泰和东准噶尔地体已经拼合。

关键词：额尔齐斯杂岩变碎屑岩物源分析碎屑锆石

Structural,Kinematic and Geochronological Study of the Main Tianshan Shear Zone in the Borohoro Ranges,NW China

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Acta Geologica Sinica(English Edition) 2021年第5期95卷 1431-1455页

作者： LIU Tianlun CHEN Siyu ZhanG Bo CAI Keda han baofu QU Junfeng GUO Lei WANG Meng The Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking UniversityBeijing 100871China School of Earth Sciences and Resources China University of Geosciences(Beijing)Beijing 100083China Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China Key Laboratory for the Study of Focused Magmatism and Giant Ore Deposits MNRSchool of Earth Science and ResourcesChang'an UniversityXi'an 710054China

The western segment of the Main Tianshan shear zone(MTSZ)branches into three major dextral strike-slip shear zones in the Borohoro Ranges,northwestern China.Mylonitic rocks within these zones exhibit vertical foliations,subhorizontal lineations,and dextral kinematics.The microstructures and CPO patterns of calcite and quartz in the tectonites suggest shearing at temperatures of 200℃ to 500℃ or above.The amount of dextral displacement along the zones is less than 100 km.LA-ICP-MS U-Pb dating of zircons from some pre-kinematic granites gave ages of 364-325 Ma and 316 Ma,and zircons from a syn-kinematic leucogranite gave an age of 291 Ma.We propose that dextral shearing along the MTSZ started in the earliest Permian.Our data indicate that collision between the Yili and Junggar plates might have finished before 325 Ma or 316 Ma,with a tectonic transformation from 325 Ma to 300 Ma,resulting in intracontinental transpression from 300 Ma or 291 Ma.We suggest that the formation of the Kazakhstan orocline(KO)took place in two stages,with the early stage of bending driven by convergence related to oblique subduction,and the late stage possibly associated with lateral disarticulation as a result of the dextral strike-slip shear zones.

关键词： structural geology geochronology dextral shearing CPO pattern Late Paleozoic Main Tianshan Shear Zone Yili-North Tianshan

华北克拉通西部陆块北缘新生代岩石圈地幔特征的初步研究

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岩石学报 2011年第10期27卷 2912-2926页

作者：王亚妹 William L GRIFFIN 韩宝福 WANG YaMei han baofu 北京大学造山带与地壳演化教育部重点实验室北京大学地球与空间科学学院北京100871 澳大利亚麦考瑞大学地球与行星科学系 GEMOC国家重点实验中心NSW2109 澳大利亚勘探与找矿CSIRO中心North Ryde NSW2113

凉城、四子王旗、三义堂和大同的地幔包体的岩石学和矿物的主、微量元素成分显示华北克拉通中、西部北缘总体为过渡型岩石圈地幔,为原始地幔经过不同程度的熔体抽取和后期交代富集作用的残留。凉城岩石圈地幔经历的熔体抽取程度最低,后... 详细信息

凉城、四子王旗、三义堂和大同的地幔包体的岩石学和矿物的主、微量元素成分显示华北克拉通中、西部北缘总体为过渡型岩石圈地幔,为原始地幔经过不同程度的熔体抽取和后期交代富集作用的残留。凉城岩石圈地幔经历的熔体抽取程度最低,后期交代富集作用比较强烈,这与其橄榄岩中尖晶石的Cr#较低,并且共存的单斜辉石的Mg#较低一致。三义堂岩石圈地幔经历的熔体抽取程度最高,后期交代富集作用最强烈,不同样品甚至同一样品中不同单斜辉石颗粒的La/Yb和LREE配分模式变化范围非常大,且矿物边部比核部更富集微量元素。大同、四子王旗岩石圈地幔经历的熔体抽取程度介于凉城和三义堂之间,但后期的交代富集作用明显不如凉城和三义堂强烈。研究区的岩石圈地幔主要受硅酸盐熔体交代作用的影响,只有三义堂岩石圈地幔还可能也受到了碳酸盐交代作用的影响。

关键词：岩石圈地幔地幔包体西部陆块华北克拉通

The Middle Devonian Bimodal Association of Volcanic Rocks in the Northern Area of East Junggar, Xinjiang

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Acta Geologica Sinica(English Edition) 1992年第2期66卷 141-153页

作者： han baofu Department of Geology, Peking University, Beijing Department of Geology Peking University Beijing

The Middle Devonian volcanic rocks in the northern area of East Junggar, located between the Ertix andUlungur rivers of northern Xinjiang, may be divided into basic and acid ones. It is evident that a compositionalgap exists between the two groups so that the volcanic rocks are not in line with a calc-alkaline series becausethe intermediate rocks are absent in the area. The fact shows that the volcanic rocks are a typical bimodal asso-ciation. The formation of the bimodal association of volcanic rocks in the area was closely related to continen-tal rifting or continental extension in the Middle Devonian. In such a tectonic setting, magmas were first pro-duced by partial melting of the mantle. Where crustal thinning was greater, the magmas ascended and eruptedon the surface directly so that the basic volcanic rocks formed, but olivine and/or partial pyroxenefractionation occurred in the magmas during their ascent through the thinning crust. On the other hand, wherecrustal thinning was less, ascending mantle-derived magmas reached the lower crust and accumulated there, re-sulting in partial melting of the lower crust and thus giving rise to the contaminated magma which was consoli-dated as acid volcanic rocks on the surface.

关键词： rock REE area The Middle Devonian Bimodal Association of Volcanic Rocks in the Northern Area of East Junggar Xinjiang

Discovery of a Miocene Mafic Dyke from the Western Hills of Beijing and its Geological Implications

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Acta Geologica Sinica(English Edition) 2009年第3期83卷 640-647页

作者： ZhanG Zhicheng han baofu WU Tairan Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of Education School of Earth and Space Sciences Peking University Beijing 100871 China

The present study is the first report of a Miocene mafic dyke from the Dahuichang, in the Western Hills of Beijing. The dyke cuts the fossil-dated Changxindian Formation of Eocene sequences and yields K-Ar ages of 14-15 Ma. The dyke is fine-grained diabase and has 49.84%-50.81% SiO2 and 3.56-3.97% Na2O＋K2O, high TiO2 （1.65%-1.93%） and MgO （7.36%-9.85%）, and low K2O （〈1.22%） contents, with Na2O〉K2O and slightly varied magnesium numbers （Mg#=55.54-62.74）. In trace elements geochemistry, the dyke is very similar to the Miocene basalts from Jining and hanuoba. The enrichment of light rare earth elements （[La/Yb]N=5.03-6.12） and large ion lithophile elements （LILEs）, no negative Eu anomalies, relatively high Cr （265-326 ppm） and Ni （155-262 ppm）, and almost constant V concentrations （194-213 ppm） reveal that the composition close to the primary basaltic magma from an enriched-mantle source, with little crustal contamination and fractional crystallization. The basaltic magma was possibly derived from the upwelling asthenosphere mantle beneath eastern China during the Miocene lithospheric thinning.

关键词： Miocene mafic dyke Dahuichang Western Hills of Beijing

Geochemical characteristics of the metapelites from the Xingxingxia group in the Eastern Segment of the Central Tianshan:Implications for the provenance and paleoweathering

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Science China Earth Sciences 2005年第10期48卷 1637-1648页

作者： LI Qiugen LIU Shuwen han baofu WANG Yueran DANG Qingning The Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of Education School of Earth and Space Sciences Peking University Beijing 100871 China The Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of Education School of Earth and Space Sciences Peking University Beijing 100871 China The Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of Education School of Earth and Space Sciences Peking University Beijing 100871 China The Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of Education School of Earth and Space Sciences Peking University Beijing 100871 China The Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of Education School of Earth and Space Sciences Peking University Beijing 100871 China

Metapelites from the Mesoproterozoic Xingxingxia group in the Eastern Segment of the Central Tianshan, Northwestern China, were analyzed for major and trace elements, includ-ing rare earth elements. Compared with post-Archean shales, the metapelites are enriched in Sr, Hf and Zr. The other elements are similar to the compositions of the Phanerozoic North American Shale Composite and the Post-Archean Australian average Shale (PAAS). The characteristics of Al2O3/TiO2, Cr/Zr, Cr/Th, Th/Sc and high Zr concentration suggest that these pelites could be derived from a significant proportion of felsic and a few proportion of participation of mafic mate-rials in nature. These rocks display highly fractionated REE patterns, and average (La/Yb)n = 18.6. Several samples have slightly negative Eu anomalies (Eu/Eu* = 0.7―0.84) in comparison with PAAS (Eu/Eu* = 0.65), indicating contribution from young immature materials. The low K2O/Al2O3 values of these metapelites suggest that their source materials could contain minimal alkali feldspar. In the A-CN-K triangular diagram, the sample data array intersects the feldspar join, indicating that the source had a plagioclase: K-feldspar ratio of approximately 5:1, repre-senting weathered products from components that could approximately correspond to granodio-rites and tonalites. The low Chemical Index of Alteration (CIA) and high Index of Compositional Variability (ICV) values suggest low degrees of weathering of the source and low compositional maturity of the sediments, respectively. The geochemical characteristics of the metapelites from the Xingxingxia group also demonstrate that these sediments were deposited in a back-arc background within a continental-arc system.

关键词： Eastern Segment of the Central Tianshan, metapelites from the Xingxingxia group, geochemistry, provenance, paleoweathering, tectonic setting.

A rare zigzag mud crack

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Chinese Science Bulletin 1999年第4期44卷 380-381页

作者： Tairan Wu Guoqi He baofu han Peking Univ Dept Geol Beijing 100871 Peoples R China

MUD crack is a common bedding-plane structure, but the zigzag mud cracks (figs. 1 and 2) are rare phenomena that were found beside G314 highway from Kaxgar to Taxkorgan in Xin-jiang, China. From the photographs we can find that there are footprints of a small animal at every top of zigzag. The zigzag cracks were controlled admittedly by the animal slightly disturbing just when they were breaking. There is a phenomenon worth researching further (fig. 1 ). Distributing equality of zigzags, the horizontal crack (F1) is cracked along the footprints strictly. The vertical one (F2) was not cracked regularly and confined by F1. The crack was

关键词： A rare zigzag mud crack