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Science china Earth Sciences 2008年第2期51卷 294-299页

作者： li yongxiang1 & xue xiangxu1,2 1 state key laboratory of continental dynamics, department of geology, northwest university, institute of cenozoic geology and environment, xi’an 710069, china 2 institute of Earth environment, state key laboratory of Loess and Quaternary geology, Chinese Academy of Sciences, xi’an 710075, china state key laboratory of continental dynamics Department of Geology Northwest University Institute of Cenozoic Geology and Environment institute of Earth environment State Key Laboratory of Loess and Quaternary Geology Chinese Academy of Sciences

Three microtine species are recovered from the Zhangping Caves of the Qingling Mountains, namely Microtus oeconomus, Caryomys inez and Caryomys eva. They are climate-sensitive ones with different ecological habits, therefore their distribution well corresponds to environmental variations. Statistical comparison of the distribution of fossil microtines and their counterparts nowadays displays that the climate variation of the studied area and its contiguity since the middle Pleistocene are: warm and humid at 493 ka ago, cool and humid at 259 ka ago―cold and humid at 205 ka ago―cool and humid at 28 ka ago, and warm and dry at present.

关键词： environmental variation since Middle Pleistocene microtine fossils Zhangping Caves of the Qinling Mountains

Paleoenvironments indicated by the fossil mammalian assemblages from red clay-loess sequence in the Chinese Loess Plateau since 8.0 Ma B.P.

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Science china Earth Sciences 2006年第5期49卷 518-530页

作者： xue xiangxu1,2, ZHANG Yunxiang1,2 & YUE Leping1,2 1. state key laboratory of Continent dynamics (northwest university), institute of cenozoic geology and environment, De- partment of geology, northwest university, xi’an 710069, china 2. institute of Earth environment, state key laboratory of Loess and Quaternary geology, Chinese Academy of Sciences, xi’an 710075, china state key laboratory of Continent dynamics (northwest university) Institute of Cenozoic Geology and Environment Department of Geology Northwest University Xi’an China institute of Earth environment State Key Laboratory of Loess and Quaternary Geology Chinese Academy of Sciences Xi’an China

Information from eleven profiles of eolian earthy red silty clay and loess of the middle of the Late Miocene to Holocene age have been studied and correlated. A complete summary profile with projected isotopic ages and fossil-bearing beds has been assembled. The profile is subdivided into 12 stratigraphic units proceeding from the lower (older) to the upper (younger) one. The character of mammalian assemblages contained in each unit was analyzed and the corresponding pa- leo-climatic environments were deduced. The environmental character of each period and the change from the middle of the Late Miocene at about 8.0 Ma B.P. up to the Holocene progressed from the hot semiarid and semi-moist, warmer-moist, warm-moister of the Late Miocene. To slightly less warm moist, cool-dry, slight-warmer-moister of the Pliocene; later the cool to cold dry periods alternated frequently with the mild semiarid and semi-moist periods of the Quaternary. Vegetation progressed from the grasslands with sparse woods, wooded shrub-grasslands and subtropical forest-grasslands of the Late Miocene age to sparse grasslands and dry grasslands of the Pliocene; and to sparse grasslands, dry grasslands and tundras of the Quaternary. The climate changes in the Neogene were of low-amplitute in a generally warm-humid background. Those of the Quaternary were of higher am- plitude with a longer phase. Cool or cold dry and slightly warm semiarid and semi-moist climates al- ternated on a generally cool-dry background. The tendency since the start of the Quaternary was the change to more northern and western shift in the Loess Plateau, with progressively cooler and dryer conditions. The dramatic uplift of the Qinghai-xizang (Tibet) Plateau and the forming and expansion of the Arctic ice sheet might be the main reasons of the more pronounced changes in the Quaternary.

关键词： paleoenvironment, mammalian fossils, eolian red clay-loess sequence, Loess Plateau.

New fossils of the Early Pleistocene Equus huanghoensis(Equidae,Perissodactyla)from Nihewan in Hebei Province of china

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Science china Earth Sciences 2016年第10期59卷 83-94页

作者： li yongxiang ZHANG Yunxiang SUN BoYang AO Hong xue xiangxu state key laboratory of continental dynamics Department of GeologyNorthwest UniversityXi'an 710069China state key laboratory of Loess and Quaternary geology Institute of Earth EnvironmentChinese Academy of SciencesXi'an 710061China Tianjin Museum of Natural History Tianjin 300201China

This paper describes new fossils of Equus huanghoensis from an Early Pleistocene bed in Nihewan, Hebei Province, which confirms the classification of E. huanghoensis by Chinese researchers. The new fossils include a relatively complete male skull and mandible with all upper and lower dentition, a broken female skull with fragment of mandible and a broken Mc III of Equus sp. The fossils were collected from the Yangshuizhan site of Nihewan. The age of the formation is about 1.6 Ma. The new materials verify some classification characteristics based on teeth published in previous descriptions. These characteristics include large teeth size, short protocone, and tilted protoloph and metaloph. We have added to these characteristics of large skull size, a developed protuberantia supramagna, pentagonal nuchal side, weak Pli cabaline, simple enamel plications; a series of new characteristics strikingly different from the other Equus horses. The broken Mc III is similar to Equus qingyangensis from Qingyang, Gansu.

关键词： Nihewan Early Pleistocene Equus huanghoensis New fossils

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Carbon isotopes,sulfur isotopes,and trace elements of the dolomites from the Dengying Formation in Zhenba area,southern Shaanxi:Implications for shallow water redox conditions during the terminal Ediacaran

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Carbon isotopes,sulfur isotopes,and trace elements of the do...

Constraining the timing of the India-Asia continental collision by the sedimentary record

中国科学院地质与地球物理研究所2015年度（第15届）学术年会

作者： CHEN Ya li CHU xue Lei ZHANG xing liang ZHAI Ming Guo state key laboratory of lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of Sciences College of Earth Science University of Chinese Academy of Sciences state key laboratory for the continental dynamics Northwest University

Carbon isotope,sulfur isotope,and trace element(including Rare Earth Elements,REE)analyses were conducted on the carbonates of the Dengying Formation at lianghekou section in southern Shaanxi to reconstruct the terminal Ediacaran shallow-water environment on the northwestern margin of the Yangtze *** lianghekou section,samples in the middle50-m of the Beiwan Member show characteristics of low∑REE concentrations,no MREE-enriched REE distribution patterns,high Ce/Cevalues close to 1,and enriched redox-sensitive elements,whereas samples in the lower 30-m and upper 10-m show opposite characteristics of high SREE concentrations,MREE-enriched REE distribution patterns,low Ce/Cevalues around 0.6,and no redox-sensitive elements enriched,indicating that oxygenation did occur in the shallow water on the northwestern margin of the Yangtze Platform and redox conditions of the shallow water fluctuated from relatively oxygenated to anoxic and then back to oxygenated *** propose that the anoxia appeared in middle of the Beiwan time may associate with the anoxic upwelled *** one hand,abundant nutrients were brought in by this upwelling event,which stimulated the photosynthetic carbon fixation and increased the organic carbon burial under this anoxic condition,causing a peak of 3.6‰inδ*** the other hand,because the anoxic upwelled water replaced the oxic shallow water,together with the increasing organic matter in the water column,bacterial sulfate reduction was enhanced and therefore quickly reduced the sulfate concentration,which eventually causedδS increasing to 50‰.However,as the upwelling gradually disappeared,δC andδSvalues decreased as well in the late Beiwan time,indicating the shallow water went back to suboxic or oxic again.

关键词： Yangtze Platform southern Shaanxi Ediacaran trace elements carbon isotopes sulfur isotopes

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Science china Earth Sciences 2017年第4期60卷 603-625页

作者： HU xiuMian WANG JianGang AN Wei Eduardo GARZANTI li Juan state key laboratory of Mineral Deposits Research School of Earth Sciences and EngineeringNanjing University institute of geology and Geophysics Chinese Academy of Sciences School of Resources and environmental Engineering Hefei University of Technology laboratory for Provenance Studies Department of Earth and Environmental SciencesUniversita di Milano-Bicocca

Placing precise constraints on the timing of the India-Asia continental collision is essential to understand the successive geological and geomorphological evolution of the orogenic belt as well as the uplift mechanism of the Tibetan Plateau and their effects on climate,environment and *** on the extensive study of the sedimentary record on both sides of the Yarlung-Zangbo suture zone in Tibet,we review here the present state of knowledge on the timing of collision onset,discuss its possible diachroneity along strike,and reconstruct the early structural and topographic evolution of the Himalayan collided *** define continent-continent collision as the moment when the oceanic crust is completely consumed at one point where the two continental margins come into *** use two methods to constrain the timing of collision onset:(1) dating the provenance change from Indian to Asian recorded by deep-water turbidites near the suture zone,and(2) dating the age of unconformities on both sides of the suture *** first method allowed us to constrain precisely collision onset as middle Palaeocene(59±l Ma).Marine sedimentation persisted in the collisional zone for another 20-25 Ma locally in southern Tibet,and molassic-type deposition in the Indian foreland basin did not begin until another 10-15 Ma *** sedimentary evidence failed to firmly document any significant diachroneity of collision onset from the central Himalaya to the western Himalaya and Pakistan so *** on the cenozoic stratigraphic record of the Tibetan Himalaya,four distinct stages can be identified in the early evolution of the Himalayan orogen:(1) middle Palaeocene-early Eocene earliest Eohimalayan stage(from 59 to 52 Ma):collision onset and filling of the deep-water trough along the suture zone while carbonate platform sedimentation persisted on the inner Indian margin;(2) early-middle Eocene early Eohimalayan stage(from 52 to 41 or 35 Ma):filling of intervening seaways and

关键词： India-Asia continental collision Timing of collision onset Himalayan orogeny Tibet Himalaya Sedimentary record

南海北部白垩纪-渐新世早期沉积环境演变及构造控制

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古地理学报 2022年第1期24卷 73-84页

作者：吴哲张丽丽朱伟林邵磊杨学奇中海石油(中国)有限公司深圳分公司广东深圳518054 同济大学海洋地质国家重点实验室上海200092

南海北部珠江口—琼东南盆地白垩系—下渐新统记录了华南大陆边缘从主动陆缘向被动陆缘的转换过程。基于盆地构造-地层、单井相、地震相等特征的综合分析,结合南海中南部的沉积环境和区域构造演化,探讨南海北部白垩纪—渐新世早期的沉... 详细信息

南海北部珠江口—琼东南盆地白垩系—下渐新统记录了华南大陆边缘从主动陆缘向被动陆缘的转换过程。基于盆地构造-地层、单井相、地震相等特征的综合分析,结合南海中南部的沉积环境和区域构造演化,探讨南海北部白垩纪—渐新世早期的沉积环境演变及构造控制背景。研究发现:(1)南海北部白垩系广泛分布,古新统分布极为有限;始新世早-中期,琼东南盆地只在部分凹陷深部发育了小规模的滨浅湖相和扇三角洲相沉积,珠江口盆地白云凹陷以大规模发育的湖泊相为特征;始新世晚期—渐新世早期,琼东南盆地和珠江口盆地白云凹陷都受到海侵作用的影响,以海岸平原相和滨浅海相为主。(2)构造演变包括5期:包括白垩纪安第斯型大陆边缘的“弧—盆”体系发育期,古新世区域隆升剥蚀山间盆地发育期,始新世早-中期裂陷发育,始新世晚期—渐新世早期陆缘破裂期,渐新世晚期东部海盆稳定扩张期。最后,探讨了南海盆地中生代末/新生代初的动力学转换过程及特征。

关键词：南海珠江口盆地琼东南盆地沉积环境构造古地理

山东半岛石笋记录的倒数第二次冰消期δ18O变化特征及其气候环境意义

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第四纪研究 2019年第4期39卷 812-824页

作者：薛刚蔡演军马乐成星李东卫莹莹中国科学院地球环境研究所黄土与第四纪地质国家重点实验室陕西西安710061 中国科学院大学北京100049 中国科学院第四纪科学与全球变化卓越创新中心陕西西安710061 青岛海洋科学与技术试点国家实验室海陆气候环境变化开放工作室山东青岛266061 西安交通大学全球环境变化研究院陕西西安710054

文章基于山东半岛岩溶洞穴(上小峰洞)一根长约41 cm的石笋SD1的铀系测年和稳定同位素组成分析,获得138. 0~125. 8 ka B. P.平均分辨率为30年的石笋δ18O 和δ13C时间序列,并据此讨论了倒数第二次冰消期区域气候和环境变化的特征及与全... 详细信息

文章基于山东半岛岩溶洞穴(上小峰洞)一根长约41 cm的石笋SD1的铀系测年和稳定同位素组成分析,获得138. 0~125. 8 ka B. P.平均分辨率为30年的石笋δ18O 和δ13C时间序列,并据此讨论了倒数第二次冰消期区域气候和环境变化的特征及与全球变化的联系.在倒数第二次冰消期,上小峰洞石笋( SD1)δ18O的变化与中国南方石笋δ18O的变化具有类似的阶段变化特征,进一步确认了冰消期北大西洋气候对亚洲季风的重要影响.通过对山东石笋高分辨δ18O记录进行时间序列分析,发现该记录存在显著的约60年、 75年和1620年周期,表明太阳活动和北大西洋涛动与该地区气候变化有紧密的联系.同时,通过对比东亚季风区高分辨率石笋记录,认为在倒数第二次冰消期为"两步冰消"的变化特征.除此之外,上小峰洞石笋碳酸盐δ18O冰期和间冰期平均值的差异仅为0. 7‰,远小于内陆洞穴石笋碳酸盐δ18O冰期和间冰期平均值的差异(羊口洞约为1. 4‰,董哥洞约为2. 2‰,三宝洞约为2. 4‰).这一显著差异可能主要源于海岸线迁移造成的海陆格局的变化对区域季风降水及降水氧同位素组成的重要影响;并且冰期-间冰期海平面变化对近海环境记录、大陆架下垫面、海洋沉积物气候指标等都可能产生影响.

关键词：石笋氧同位素倒二冰消期弱季风期海岸线移动

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长江演化百年谜题:回溯与进展

地震地质 2023年第1期45卷 1-28页

作者：郭汝军魏传义李长安张玉芬李亚伟孙习林张增杰冷勇辉苏建超李国鼐吕凌云陈旭丁智强中国地质大学(武汉) 地理与信息工程学院武汉430074 中国地震局地质研究所地震动力学国家重点实验室北京100029 中国地质大学(武汉) 流域关键带演化湖北省重点实验室武汉430074 中国地质大学(武汉) 地球物理与空间信息学院武汉430074 平顶山学院旅游与规划学院平顶山467000 湖北大学资源环境学院武汉430062 中山大学地球科学与工程学院广州510275 云南师范大学旅游与地理科学学院昆明650500

长江的形成标志着中国地貌格局的形成与东亚现代地貌格局的建立。文中简述了百余年间长江演化研究的主要争论,梳理了近20年来将物源示踪方法应用于长江演化研究的进展及得到的启示。通过对长江流域的典型沉积体系:包括上游昔格达组、剑... 详细信息

长江的形成标志着中国地貌格局的形成与东亚现代地貌格局的建立。文中简述了百余年间长江演化研究的主要争论,梳理了近20年来将物源示踪方法应用于长江演化研究的进展及得到的启示。通过对长江流域的典型沉积体系:包括上游昔格达组、剑川盆地、中下游砾石层、江汉盆地、长江三角洲钻孔沉积及边缘海盆地(莺歌海盆地、中国台湾岛)的物源示踪结果进行归纳梳理,笔者认为:1)长江演化争论的焦点问题依旧是三峡贯通和石鼓第一弯的形成,但争论的问题已拓宽至古水系模式、侵蚀-沉积过程、夷平面形成等诸多问题。2)三峡贯通和石鼓第一弯形成的时代尚未取得共识,即长江的形成时代和过程还存在争论。长江中下游砾石层和江汉盆地沉积物具有复杂的源区供应,仅依靠碎屑锆石U-Pb年代学无法有效区分长江上游的物源信号;江汉盆地和长江三角洲钻孔沉积记录对于三峡贯通的初始信号仍未达成一致;剑川盆地和昔格达组沉积物的年代及其物源意义对于金沙江南流(东流)的指示意义存在广泛争论;海洋沉积约束长江和红河水系演化模式的物源信号也存在争议。3)在长江流域各沉积盆地进行物源研究时,建议加强海陆沉积对比。从地貌-构造演化-沉积古地理-气候变迁的角度,将能更加全面地重建长江演化的历史。

关键词：长江演化争论与进展物源示踪长江三峡长江第一弯

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龙门山南段前陆大川-丹棱剖面磁组构特征及其构造意义

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大地构造与成矿学 2023年第1期47卷 66-79页

作者：余文鑫陈应涛张国伟鲁如魁张欢李阳西安科技大学地质与环境学院陕西西安710054 陕西省煤炭绿色开发地质保障重点实验室陕西西安710054 西北大学地质学系/大陆动力学国家重点实验室陕西西安710069

龙门山南段前陆盆地作为龙门山构造带南段盆-山耦合关系的具体响应,其中-新生代沉积地层的构造变形特征和叠加改造关系在一定程度上反映了龙门山构造带南段的形成与演化。本文基于横跨龙门山南段前陆的大川-丹棱剖面,通过野外构造解析... 详细信息

龙门山南段前陆盆地作为龙门山构造带南段盆-山耦合关系的具体响应,其中-新生代沉积地层的构造变形特征和叠加改造关系在一定程度上反映了龙门山构造带南段的形成与演化。本文基于横跨龙门山南段前陆的大川-丹棱剖面,通过野外构造解析和岩石磁组构特征,对前陆构造变形开展精细研究。构造解析揭示,剖面上发育一系列与双石断裂带走向近平行的宽缓褶皱和浅层逆冲断层,褶皱表现为北西翼较缓,而南东翼相对较陡,轴面略向NW倾的不对称特征。磁组构特征揭示,剖面中岩石具低磁化率和典型的沉积岩三轴磁化率椭球体的特征,磁化率椭球体以扁圆形为主,整体反映出弱变形的特征,与褶皱作用前的平行层缩短(LPS)相关;最大磁化率主轴(Kmax)优势方位为NE-SW向,与龙门山构造带走向平行,主要反映了NW-SE向挤压作用。剖面还发育有磁面理与地层层面斜交、磁线理与地层走向斜交两类非典型磁组构,前者是褶皱作用中层间平行简单剪切的产物,后者则是构造叠加的产物。通过磁组构反映的应变分析结果,厘定出龙门山南段前陆中生代晚期主要受到NW-SE向挤压,与新生代的挤压应力方向呈小角度斜交,且挤压作用所产生的透入性应变到达了熊坡背斜南东翼以东地区,该认识为进一步深入认识龙门山构造带的发展演化过程奠定了基础。

关键词：龙门山构造带前陆盆地磁组构平行层缩短(LPS) 透入性应变(PES)

新特提斯域演化对波斯湾超级含油气盆地形成的影响

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石油勘探与开发 2023年第1期50卷 1-11页

作者：朱日祥张水昌万博张旺李勇王华建罗贝维柳宇柯何治亮金之钧中国科学院地质与地球物理研究所岩石圈演化国家重点实验室北京100029 中国石油勘探开发研究院北京100083 中国石油化工股份有限公司北京100728 北京大学能源研究院北京100871

基于新特提斯构造域动力过程及其所诱发的环境变化,并通过构建“单向列车装货”地球动力学模型,研究全球油气资源最富集的波斯湾含油气盆地形成与演化机制。研究表明:(1)单向俯冲动力过程中波斯湾超级含油气盆地自晚古生代以来长期处于... 详细信息

基于新特提斯构造域动力过程及其所诱发的环境变化,并通过构建“单向列车装货”地球动力学模型,研究全球油气资源最富集的波斯湾含油气盆地形成与演化机制。研究表明:(1)单向俯冲动力过程中波斯湾超级含油气盆地自晚古生代以来长期处于被动陆缘,区域上形成优越的油气成藏组合发育空间;(2)波斯湾超级含油气盆地在侏罗纪—白垩纪期间长期在低纬度区慢速漂移,在哈德里环流、赤道上升洋流、侏罗纪真极移等全球性地质事件的共同作用下发育了多套叠置的“源-储-盖”组合;(3)新生代以来的前陆盆地演化阶段碰撞破坏作用弱,有利于油气资源保存。在波斯湾超级含油气盆地实例解剖的基础上,提出陆块慢速漂移及在有利气候带长时间留置是油气富集的关键因素,并对特提斯域内其他陆块的油气资源前景进行了展望。

关键词：新特提斯构造域大陆裂解汇聚单向列车装货模型环境变化波斯湾超级含油气盆地