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New fossil materials of Sus lydekkeri from the Early Pleistocene Shanshenmiaozui site in Nihewan Basin of North China 被引量:1
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作者 TONG Hao-Wen CHEN Xi +1 位作者 ZHANG Bei SUN Ji-Jia 《古脊椎动物学报(中英文)》 北大核心 2025年第3期210-241,共32页
Suid is one of the most common taxa among the Pleistocene mammalian fauna in China.However,its phylogenetic taxonomy and evolution are far from clear.The newly recovered suid fossil materials from the Early Pleistocen... Suid is one of the most common taxa among the Pleistocene mammalian fauna in China.However,its phylogenetic taxonomy and evolution are far from clear.The newly recovered suid fossil materials from the Early Pleistocene Shanshenmiaozui site in Nihewan Basin in North China provide new insight into the evolution of its kind in North China.The new materials include partial skulls and mandibles of males,and most of their teeth were preserved in situ.The specimens can be referred to the species Sus lydekkeri,which is the only species of Sus found in North China from the Early Pleistocene.The fossils of the once reported Pleistocene species“Potamochoerus chinhsienensis”should also be provisionally included in the species S.lydekkeri according to its form and size,which at least now excludes it from Potamochoerus.The species S.lydekkeri is very close to the extant species S.scrofa,and even was combined into the latter as a chronological subspecies by some authors,while its larger size,prominent preorbital fossa,backwardly positioned infraorbital foramen,frequently appearing verrucosic type(at least the intermediate type of the male lower canine),and simple crown structures support its validness as an independent species.The Early Pleistocene forms are characterized by a larger size,lower L/W ratio of cheekteeth,both upper and lower M3s having no more than three lobes,and the male lower canine is exclusively of a verrucosic type.Suid fossils are a very good indicator of paleoenvironments and paleoclimate.Both the northern and the southern faunas in China contain suid fossils throughout the Pleistocene Epoch,while the southern fauna has prominently more diversified taxa and more abundant fossil collections;whether that is caused by different origins or by environmental modifications is still not clear. 展开更多
关键词 Shanshenmiaozui of Nihewan North China Early pleistocene Sus lydekkeri
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Discovery of Pleistocene fruit bat Rousettus and its coexisting non-volant micromammalian fossils from the Guilin Basin,South China
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作者 Rana Mehroz FAZAL HE Zhan-Wu +5 位作者 DU Bao-Pu CHANG Mei-Jing SHI Jing-Song NI Xi-Jun LI Qiang ZHAO Ling-Xia 《古脊椎动物学报(中英文)》 北大核心 2025年第3期173-188,共16页
In 2015,the discovery of mammalian fossils,paleolithic artifacts,and burned bones in the Maoershan Cave of the Guilin Basin,northeastern Guangxi,indicated that it is a late Middle Pleistocene Paleolithic site.In 2021,... In 2015,the discovery of mammalian fossils,paleolithic artifacts,and burned bones in the Maoershan Cave of the Guilin Basin,northeastern Guangxi,indicated that it is a late Middle Pleistocene Paleolithic site.In 2021,stratigraphic sectioning and the systematic screening of small mammal sand samples were conducted.This paper presents a comprehensive account of the new material of the fruit bat Rousettus leschenaultii,accompanied by a concise overview of the non-volant micromammals that coexisted with it in the Quaternary sediments of the Maoershan Cave.This finding marks the second occurrence of fruit bat fossils in China,contributing to our understanding of the dental morphology and past geographical distribution of Rousettus.The micromammalian assemblage of the Maoershan Cave is composed of 3 orders,9 families,26 genera,and 30 species,and exhibits notable similarities with those of the late Middle Pleistocene Yumi Cave,Xinglong Cave,Yanhui Cave,Mawokou Cave,Zhongliangshan,and Chuan Cave faunas.The biochronology of the micromammalian assemblage from the Maoershan Cave has been determined to be consistent with the late Middle Pleistocene,providing a new assemblage in the Pleistocene mammalian faunal sequence in southern China.The presence of abundant oriental forested elements indicates that the Guilin Basin used to be a humid and warm subtropical forest paleoenvironment similar to the contemporary environment during the late Middle Pleistocene. 展开更多
关键词 Guilin Basin late Middle pleistocene fruit bat micromammalian assemblage BIOSTRATIGRAPHY PALEOENVIRONMENT
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Origin and Evolution of the Late Middle Pleistocene Trachytes in the Changbaishan Tianchi Volcano(China/North Korea):Insights from Mineralogy,Geochronology and Geochemistry
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作者 YE Xiqing XU Zhitao +2 位作者 Guido VENTURA SUN Liying LI Zhongwei 《Acta Geologica Sinica(English Edition)》 2025年第3期774-788,共15页
Cenozoic trachytes are characteristic of some active volcanic fields in China.In particular,the origin and mechanisms of the evolution of trachytes from the Tianchi(Changbaishan)volcano(TV,China/North Korea)are poorly... Cenozoic trachytes are characteristic of some active volcanic fields in China.In particular,the origin and mechanisms of the evolution of trachytes from the Tianchi(Changbaishan)volcano(TV,China/North Korea)are poorly known.Here,we present new geochronological,geochemical and isotopic data on two trachytic suites outcropping on the northern and southern upper slopes of TV.Detailed zircon laser ablation-multicollector-inductively coupled plasma-mass spectrometry(LA-MC-ICP-MS)U-Pb dating,Rb-Sr isochron dating of plagioclase and hornblende,^(40)Ar/^(39)Ar chronology with mineral chemistry,whole-rock element and Sr-Nd-Pb isotope data are used to explore their origins and evolutionary mechanisms during the late Middle Pleistocene.Our data indicate that the trachytes mainly consist of sanidine,orthoclase and plagioclase,with minor albite,quartz and hornblende.They formed at 0.353-0.346 Ma(lava flow from the northern slope)and 0.383-0.311 Ma(lava flow from the southern slope),respectively.The TV trachytes are characterized by high K_(2)O/Na_(2)O and AR values,with low A/CNK and Mg~#values.They are enriched in rare earth elements(REEs;except Eu),depleted in Sr and Ba,crystallizing at 742-858℃.The TV trachytes have high(^(87)Sr/^(86)Sr)_i values(0.70776-0.71195),positiveε_(Nd)(t)values(0.61-2.93)and radiogenic^(206)Pb/^(204)Pb values(17.515-17.806).These values are similar to those of the Pleistocene and Holocene TV trachytes.Geochemical data indicate that they were formed by fractional crystallization from a basaltic melt and assimilated upper crust material.The trace element pattern of the studied trachytes is consistent with an evolution from basaltic melts representative of an enriched mantle source.The vent from which the trachytic magma was erupted probably collapsed inside the caldera during the TV'Millennium'eruption(ME)in 946 AD.The contemporaneous emission of basaltic and trachytic magma during the Middle-Late Pleistocene suggests the coexistence of fissural basaltic volcanism and central-type trachytic volcanism,the latter of which was associated with a magma chamber in the upper crust during the TV cone-construction stage. 展开更多
关键词 trachytes CHRONOLOGY GEOCHEMISTRY late Middle pleistocene magmatism Changbaishan Tianchi volcano
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Paleoenvironmental reconstruction of human adaptation in the Nihewan Basin of North China during Middle Pleistocene:A case study of Jijiazhuang archaeological site
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作者 PEI Shuwen XU Jingyue +3 位作者 DU Yuwei YE Zhi GENG Shuaijie LIU Ziyi 《Journal of Geographical Sciences》 2025年第8期1601-1618,共18页
Situated in the semi-arid regions of North China,the Nihewan Basin documents the fluvio-lacustrine sequence and Pleistocene archaeological sites,offering an excellent opportunity to investigate human adaptation to env... Situated in the semi-arid regions of North China,the Nihewan Basin documents the fluvio-lacustrine sequence and Pleistocene archaeological sites,offering an excellent opportunity to investigate human adaptation to environmental change in East Asia,especially in North China.However,paleoenvironmental datasets from Middle Pleistocene archaeological sites are not fully understood.Focusing on the evidence from the 0.63-0.49 Ma-old site of Jijiazhuang(Nihewan Basin,North China),this paper presents the results of various environmental indicators from the site context.Moreover,it explores the links between hominin behavioral adaptations and ecological variability during the extra-long interglacial period in North China.Sedimentological features of the excavated section indicate that the site was formed in the margin of the Nihewan paleolake.Based on well-constructed pollen,sediment grain size,color reflectance,and major geochemical element analyses,five stages of environmental changes were identified during site formation.This study indicates that hominins occupied the site at the early part of Stage 2,when the Nihewan paleolake had a relatively low water level and the climate was temperate,with strong weathering intensity dominated by wooded grassland landscapes.In conclusion,the results suggest that the extra-long duration of interglacial or mild stadial climate events(MISs 15-13)in the Northern Hemisphere may have provided favorable conditions for increased technological innovations and adaptive strategies among Middle Pleistocene hominins in the Nihewan Basin even in North China. 展开更多
关键词 Middle pleistocene paleoenvironmental reconstruction human adaptation Jijiazhuang site(JJZ) Nihewan Basin North China
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Homo jinniushanensis sp.nov.(Middle Pleistocene hominin)recognized in Liaoning Province,China
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作者 Ji Qiang Ji Yannan +2 位作者 Chen Shaokun Liu Aoran Han Kaibo 《地质学刊》 2025年第3期229-234,共6页
In 2024,Ji Qiang et al.established a new species,namely,Homo yunxianensis,based on the fossil human cranium(EV9001)unearthed from the Xuetangliangzi site of Yunxian County,Hubei Province,China,and characterized by dev... In 2024,Ji Qiang et al.established a new species,namely,Homo yunxianensis,based on the fossil human cranium(EV9001)unearthed from the Xuetangliangzi site of Yunxian County,Hubei Province,China,and characterized by developing 16 teeth on the maxilla,two slightly curved,thick brow ridges,but no sagittal ridge along the cranial midline.Homo yunxianensis developed the skull of type C,which was considered as the descendant of Homo erectus and later evolved into Homo orientalis with 31 to 29 teeth orally.In this paper,we restudy the skull(the holotype)of the Jinniushan man,which was found in the cave crevasse deposit(Point A)on the southeast slope of the Jinniushan Hill in Yingkou City,Liaoning Province by the teachers and students of the Archaeology Department of Peking University in 1984.The skull shows some distinct characters as follows:the cranial fornix is medium tall;the sagittal ridge does not developed;the brow ridges are thick and slightly curved;the upper jaw has 16 teeth preserved in situ;and the posterior end(the transition part)is obtuse in shape.These features mentioned above show that the Jinniushan cranium represents a new species:Homo jinniushanensis sp.nov.,rather than Homo erectus,Homo yunxianensis,and archaic or early Homo sapiens.We suggested that Homo jinniushanensis sp.nov.is probably the intermediate form transitional from Homo yunxianensis to Homo(H.)sapiens. 展开更多
关键词 Homo jinniushanensis sp.nov. skull fossil Middle pleistocene Yingkou City Liaoning Province China
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New ^(10)Be-^(26)Al isochron burial dating informs the Pliocene and Pleistocene evolution of the lower Colorado River, southwestern United States
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作者 Yeong Bae Seong Ryan Crow +3 位作者 P.Kyle House Keith Howard Cho-Hee Lee Byong Yong Yu 《Episodes》 2025年第1期51-63,共13页
Four new^(10)Be-^(26)Al isochron burial ages ranging from 4.4 to 2 Ma on ancestral Colorado River deposits in the lower Colorado River corridor(LCRC)help constrain the river’s evolution during the Pliocene and early ... Four new^(10)Be-^(26)Al isochron burial ages ranging from 4.4 to 2 Ma on ancestral Colorado River deposits in the lower Colorado River corridor(LCRC)help constrain the river’s evolution during the Pliocene and early Pleisto-cene.They help fill a gap between previous work that focused on older and younger deposits:Older dated deposits include the 5 Ma Bouse Formation,which records the integration of the Colorado River through a series of preexisting basins to the Gulf of California and the ca.4.5-3.5 Ma Bullhead Alluvium,a 200 to 300 m thick aggregational package that immediately followed integration.The much younger,100-70 ka,Chemehuevi Formation is another major aggrada-tion package mapped throughout the LCRC.The new burial ages on the facies of Santa Fe Railway(4.37±0.71 Ma),boulder conglomerate of Bat Cave Wash(2.12±0.26 and 2.05±0.31 Ma),and the Palo Verde alluvium(3.03±0.26 Ma)partially fill in a 3.5 M.y.gap between the deposition of the Bullhead Alluvium and the Chemeheuvi Formation and document the timescales over which the Colorado River was able to remove the Bullhead aggradational package and initiate newer and smaller aggradational pulses. 展开更多
关键词 be al isochron burial dating Lower Colorado River colorado river deposits southwestern United States bullhead al Santa Fe Railway pleistocene colorado river series preexisting basins
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Formal ratification of the GSSP for the base of the Calabrian Stage(second stage of the Pleistocene Series,Quaternary System)
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作者 Maria Bianca Cita Philip L.Gibbard +1 位作者 Martin J.Head the ICS Subcommission on Quaternary Stratigraphy 《Episodes》 2012年第3期388-397,共10页
The Calabrian Stage is now formally defined by the Global Boundary Stratotype Section and Point(GSSP)at Vrica,Calabria,Italy.This GSSP had previously defined the base of the Pleistocene Series.The Calabrian becomes th... The Calabrian Stage is now formally defined by the Global Boundary Stratotype Section and Point(GSSP)at Vrica,Calabria,Italy.This GSSP had previously defined the base of the Pleistocene Series.The Calabrian becomes the second stage of the Pleistocene Series and Quaternary System,following the Gelasian.The GSSP occurs at the base of the marine claystone conformably overlying sapropelic bed‘e’within Segment B in the Vrica section.This lithological level represents the primary marker for the recognition of the boundary,and is assigned an astronomical age of 1.80 Ma on the basis of sapropel calibration.It coincides with the transition from Marine Isotope Stage 65 to 64,and the underlying sapropel bed‘e’is assigned to the Mediterranean Precession-Related Sapropel layer 176.Secondary markers include calcareous plankton bioevents of widely distributed taxa.The boundary falls between the highest occurrence of Discoaster brouweri(below)and the lowest common occurrence of left-coiling Neogloboquadrina pachyderma(above),and below the lowest occurrences of medium-sized Gephyrocapsa(including G.oceanica)and Globigerinoides tenellus.The top of the Olduvai Subchron is identified c.8 m above the GSSP.Ratification of the Calabrian Stage effectively completes the Lower Pleistocene Subseries. 展开更多
关键词 calabrian stage pleistocene series pleistocene series marine claystone global boundary stratotype section point gssp GSSP Quaternary system recognition b
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The newly-ratified definition of the QuaternarySystem/Period and redefinition of the PleistoceneSeries/Epoch,and comparison of proposals advancedprior to formal ratification
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作者 Philip L.Gibbard Martin J.Head 《Episodes》 2010年第3期152-158,共7页
The base of the Quaternary System is defined by theGlobal Stratotype Section and Point(GSSP)of theGelasian Stage at Monte San Nicola in Sicily,Italy,currently dated at 2.58 Ma.The base of the PleistoceneSeries is rede... The base of the Quaternary System is defined by theGlobal Stratotype Section and Point(GSSP)of theGelasian Stage at Monte San Nicola in Sicily,Italy,currently dated at 2.58 Ma.The base of the PleistoceneSeries is redefined by the same GSSP,having previouslybeen defined by the GSSP at Vrica,Calabria,Italy,whichis dated at 1.806 Ma.These important changes to thegeological time scale were formulated through extensiveconsultation with the Quaternary community throughthe International Union for Quaternary Research(INQUA),proposed by the International Commission onStratigraphy’s(ICS)Subcommission on QuaternaryStratigraphy,endorsed by the voting membership of theICS,and ratified in June 2009 by the Executive Committeeof the International Union of Geological Sciences.Twocompeting proposals had been advanced:a‘Neogene’proposal advocated by the ICS Subcommission on NeogeneStratigraphy,and a‘Quaternary’proposal championedby the ICS Subcommission on Quaternary Stratigraphy.The status quo position would have persisted hadneither proposal received a majority of votes.Theseproposals are compared and evaluated,the‘Quaternary’proposal is presented in detail,and future directions arediscussed. 展开更多
关键词 vrica base quaternary system quaternary research quaternary system base pleistoceneseries GSSP pleistocene series monte san nicola
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Earth surface processes and their effects on human behavior in monsoonal China during the Pleistocene-Holocene epochs 被引量:13
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作者 LU Huayu ZHUO Haixin +6 位作者 ZHANG Wenchao WANG Shejiang ZHANG Hongyan SUN Xuefeng JIA Xin XU Zhiwei WANG Xianyan 《Journal of Geographical Sciences》 SCIE CSCD 2017年第11期1311-1324,共14页
There is a wide diversity of landforms in China. The topography of three major ter- races, decreasing in height stepwise from west to east, was formed by the early Miocene. With the commencement of the Great Northern ... There is a wide diversity of landforms in China. The topography of three major ter- races, decreasing in height stepwise from west to east, was formed by the early Miocene. With the commencement of the Great Northern Hemisphere Glaciations (GHGs) and the glacial-interglacial cycles in the Pleistocene, thick loess deposits accumulated in north China, and fluvial terraces were formed and lakes expanded and contracted in eastern and central China. The earliest evidence of hominins in China is dated to ~1.7 Ma; they occupied the monsoon-dominated region for a long interval, until the late Pleistocene, ~50 ka. In this study, we investigated a large area rich in the relics and artifacts of early man. The results indicate that the early humans occupied riverine areas, especially medium-sized fluvial basins, and lake shores. Even in the relatively recent geological past, the occupation and abandonment of settlements were directly forced by the shifting of sand dune fields in the desert-loess transi- tional zone, which in turn was closely associated with variations in the monsoon climate and vegetation patterns. Our observations indicate that landforms were one of the main determi- nants of early human behavior, in that loess tableland, large alluvial plains, desert-Gobi areas, and the Tibetan Plateau, were not suitable environments for early human settlement. We infer that the early humans in China adapted their behavior to specific landforms and landform processes. The monsoon climate, which shapes the large-scale step-like pattern of fluvial landforms, promotes vegetation coverage and dominates soil formation, provides a crucial context for early human adaptation. The adaptation of early humans to earth surface proc- esses in East Asia is investigated for the first time in this study. Future investigations will provide further information that will increase our understanding of the linkage between early human behavior and landform processes in East Asia. 展开更多
关键词 earth surface processes early human behavior MONSOON pleistocene HOLOCENE China
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Late Pleistocene glaciation of the Hulifang Massif of Gongwang mountains in Yunnan Province 被引量:13
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作者 ZHANG Wei CUI Zhijiu +2 位作者 FENG Jinliag YI Chaolu YA NG Jianqiang 《Journal of Geographical Sciences》 SCIE CSCD 2005年第4期448-458,共11页
Late Pleistocene glaciation was restricted to only a few high mountains in eastern China. The Gongwang mountains constitute one of the typical places once glaciated. Geomorphic mapping of the area and the TL dating pr... Late Pleistocene glaciation was restricted to only a few high mountains in eastern China. The Gongwang mountains constitute one of the typical places once glaciated. Geomorphic mapping of the area and the TL dating provides evidence for at least four distinct glaciations. YJT-Ⅰ glacial advance occurred about 100 ka BP and two TL absolute ages (101,100 ± 7780 a BP; 104,000± 8300 a BP) indicate this advance happened during the Penultimale Glaciation. The early stage glacial advance (YJT-Ⅱ advance) during the last glaciation occurred about 40,920 ± 3400 a BP. The last glacial maximum advance (YJT-Ⅲ advance) about 18-25 ka BP, which sustained by two TL ages (18,230 ±1420 a BP; 25,420 ± 2110 a BP). The Penultimale and the early stage glaciations were more extensive and the last glacial maximum (LGM) and the late-glacial period (YJT-Ⅳ advance, 10 ka BP) were progressively less extensive. Correlated with the other mountains in eastern China, these glacial advances in the Gongwang mountains just like the advances in the western part such as Diancang mountains, Yulong mountains of Yunnan Province and the glacier series are more complete than the adjacent mid-latitude regions such as Taibai mountain and Taiwan mountains and are roughly representative of climate changes during the last glacial cycle in Yunnan Province. 展开更多
关键词 glacial geomorphology TL dating late pleistocene last glaciation China
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Geochronology and Mineral Composition of the Pleistocene Sediments in Xitaijinair Salt Lake Region,Qaidam Basin:Preliminary Results 被引量:5
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作者 Fangming Zeng Shuyuan Xiang 《Journal of Earth Science》 SCIE CAS CSCD 2017年第4期622-627,共6页
Xitaijinair (XT) Salt Lake, located in the western Qaidam Basin, is significant for recon- structing the evolution of inland drying climate. However, the chronological and mineralogical records from this lake are ra... Xitaijinair (XT) Salt Lake, located in the western Qaidam Basin, is significant for recon- structing the evolution of inland drying climate. However, the chronological and mineralogical records from this lake are rare. This study investigated the chronology (accelerator mass spectrometry (AMS) 14C ages and optically stimulated luminescence (OSL) ages) and mineral compositions of sediment in the 240-cm-deep XT Section of the Xitaijinair Salt Lake region. The conclusions are drawn as follows: (1) Nine AMS 14C ages, ranging between 33 and 40 cal ka BP, are obviously younger than the two OSL ages (57.9 and 69.1 ka). The 14C ages probably reflect contamination with modern carbon. (2) Both 14C and OSL ages indicate that the surface of Xitaijinair Salt Lake region has suffered erosion. (3) The se- diments of XT Section are composed of silicates (quartz, muscovite, clinochlore and albite), carbonates (calcite, dolomite, and ankertie), halite and gypsum. 展开更多
关键词 Qaidam Basin Xitaijinair Salt Lake GEOCHRONOLOGY pleistocene.
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Sediment distribution and provenance since Late Pleistocene in Laizhou Bay,Bohai Sea,China 被引量:11
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作者 Mao-sheng Gao Fei Guo +1 位作者 Xue-yong Huang Guo-hua Hou 《China Geology》 2019年第1期16-25,共10页
There are three transgression-regression events and evolutions of the sedimentary environment by sea level changes since the Pleistocene in the southern section of the Bohai Sea, China. It is obvious that a multi-sour... There are three transgression-regression events and evolutions of the sedimentary environment by sea level changes since the Pleistocene in the southern section of the Bohai Sea, China. It is obvious that a multi-source fluvial delta sedimentary system may be more dominant in a sedimentary environment. Based on previous research and survey or historical data, we carried out studies on the division of sedimentary units, sedimentary facies analysis and strata division and comparison, which aim to establish the sedimentary stratigraph of Laizhou Bay. We focus on the sedimentary procession of the Laizhou Bay since the early Late Pleistocene. It can be divided into two glacial periods and three interglacial periods, corresponding to two regression and three transgression events in Laizhou Bay since Late Pleistocene. In 124.6-72.0 ka BP, 60.0-24.4 ka BP and 10.2-4.0 ka BP, three times warm-wet periods occurred, respectively corresponding to the Cangzhou transgression, Xianxian transgression, and Huanghua transgression. In 72.0-60.0 ka BP and 24.4-10.2 ka BP, two dry and cold periods, it was the continental sedimentary environment, corresponding to Wurm early glacier and Wurm late glacier. The results show:(1) Sediments have the characteristics of phase and stage under the terrestrial input of the Yellow River and middle-small rivers in the southern section of the Bohai Sea.(2) PI moved towards coastal in Cangzhou transgression strata in early Late Pleistocene. PI moved northward from land in Xianxian transgression strata in the late Pleistocene. PI moved further north in the Huanghua transgression strata in Holocene.(3) During the regressive period, the land source input increased and the estuarine or lagoon sedimentation developed, which manifested as progradational superposition.(4) During the transgressive period, it mainly developed shallow coastal sediment and transitionally formed regressive deposition to the south in delta/tidal flat deposition. 展开更多
关键词 Late pleistocene HOLOCENE PI Sediment Laizhou Bay
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Late Pleistocene aeolian activity in Haitan Island, Southeast China: Insights from optically stimulated luminescence dating of coastal dunes on marine terraces 被引量:5
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作者 JIN Jian-hui LI Zhi-zhong +3 位作者 CHENG Yan XU Xiao-lin LI Zhi-xing LIU Xiao-ju 《Journal of Mountain Science》 SCIE CSCD 2018年第8期1777-1788,共12页
The 'Old Red Sand' is a type of semicemented medium-fine sandy sediment that is red(10R_4/8) or brown red(2.5YR_4/8) in colour and is found in late Quaternary deposits. The sediments have distinctive character... The 'Old Red Sand' is a type of semicemented medium-fine sandy sediment that is red(10R_4/8) or brown red(2.5YR_4/8) in colour and is found in late Quaternary deposits. The sediments have distinctive characteristics and are a critical archive for understanding climatic changes in the coastal areas of East Asia. The ages of the late Quaternary aeolian sand dunes from Haitan Island in the coastal area of South China are still in debate. In this study, three sets of marine terraces were identified in the northern region of Haitan Island. Aeolian dune sands are well preserved on the top of these terraces. Quartz Optically Stimulated Luminescence dating and the distribution of the formation ages demonstrated that the palaeo-dunes are deposits from the middle-late period of the Late Pleistocene(Q_3^(2-3)). The period may be divided into three stages, 100-90 ka, 70-60 ka, and 40-20 ka, in which the palaeo-dunes of the first two stages are more widespread and were formed separately during a low-sea level period of the Marine Isotope Stages 5 b and 4. Several depositional palaeo-flood event records were preserved during the last stage due to the increasing gradient of mountain gullies formed during the Last Glacial Maximum. 展开更多
关键词 Aeolian activity Sediment dating Optically Stimulated Luminescence (OSL) Late pleistocene Environmental evolution Haitan Island
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PROBE INTO THE ORIGIN, DEVELOPMENT AND EVOLUTION MODEL OF SHELF DESERTIZATIONAL ENVIRONMENT IN THE LAST STAGE OF LATE PLEISTOCENE 被引量:3
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作者 于洪军 刘敬圃 单秋美 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1998年第4期326-332,共0页
Based on study of China’s shelf glerenvironmnt, thes paper summarises the defini-tion of shelf desertization that occurred in the last stage of be Pleistocene, and discusses the backgroundof its formation and evoluti... Based on study of China’s shelf glerenvironmnt, thes paper summarises the defini-tion of shelf desertization that occurred in the last stage of be Pleistocene, and discusses the backgroundof its formation and evolution process. Study of shallow layer profiler records and core data revealed thatcold-dry aeolian erosion was the major exogenic force on the exposed shelf. Under the prevailing paleo-winter monsoon, part of the exposed drine straum disintegzated into sand and then desertizaion oc-curred. The fine sediments were blown away and deposited on the leeward to form derivative loess de-posits. 展开更多
关键词 SHELF desertization LATE pleistocene DUNE LOESS
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Environmental evolution in the salt-water intrusion area south of Laizhou Bay since late Pleistocene 被引量:4
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作者 ZHANG Zulu LIU Enfeng +1 位作者 ZHANG Yan XIN Liangjie 《Journal of Geographical Sciences》 SCIE CSCD 2008年第1期37-45,共9页
The south coastal plain of Laizhou Bay is one of the typical salt-water intrusion areas in China, the occurrence and development of which was closely related with the palaeoenvironment evolution. Systematic analyses o... The south coastal plain of Laizhou Bay is one of the typical salt-water intrusion areas in China, the occurrence and development of which was closely related with the palaeoenvironment evolution. Systematic analyses of pollen, foraminifera and grain size composition based on ^14C and luminescence dating from two sediment cores were performed for the purpose of understanding the salt-water intrusion in the coastal plain of Laizhou Bay from the perspective of environmental evolution since late Pleistocene. It could be classified into seven evolution stages since 120 kaBP: 120-85 kaBP was a transition period from cold to warm; 85-76 kaBP was a period with warm and wet climate having swamp lakes developed in the lower reaches of the Weihe River, south coastal plain of Laizhou Bay; 76-50 kaBP was characterized by grassland vegetation and coarse sediments in terrestrial environment, which was the early stage of Dali Ice-Age; 50-24 kaBP was a period with alternate sea deposition in the south coastal plain of Laizhou Bay; 24-10 kaBP was the late stage of Dali Ice-Age with coldest period of Quaternary, the south coastal plain of Laizhou Bay was dry grassland and loess deposition environment; 10-4 kaBP was another warm and wet climate period, sea level was high and regressed at 4 kaBP; and has been the modern sedimentary environment since 4 kaBP. Among the three warm stages, including 85-76 kaBP, 50-24 kaBP and 10-4 kaBP, corresponded to late Yangkou, Guangrao and Kenli seawater transgression respectively. The duration of the latter one in south coastal plain of Laizhou Bay was longer than that in west coast of Bohai Sea and east coast of Laizhou Bay. The three periods of seawater transgression formed the foundation of salt-water intrusion in this area. 展开更多
关键词 environmental evolution salt-water intrusion late pleistocene south coastal plain of Laizhou Bay China
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Mechanical characteristics of intact Middle Pleistocene Epoch loess in northwestern China 被引量:4
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作者 钟祖良 刘新荣 《Journal of Central South University》 SCIE EI CAS 2012年第4期1163-1168,共6页
In order to research the mechanical characteristics of intact Middle Pleistocene Epoch loess, triaxial shear tests and isotonic compression test of intact Middle Pleistocene Epoch loess were conducted by improved SJ-I... In order to research the mechanical characteristics of intact Middle Pleistocene Epoch loess, triaxial shear tests and isotonic compression test of intact Middle Pleistocene Epoch loess were conducted by improved SJ-IA triaxial shear equipment. According to test results, it can be found that the intact Middle Pleistocene Epoch loess has the properties of shear dilatancy and shear shrinkage. With the increase of confining pressure, stress-strain curve develops from softening to hardening. The failure mode of intact Middle Pleistocene Epoch loess is shear failure with the rupture angle between 55° and 61°. And it is better to determine the yield stress (py, qy) of the intact loess under different confining pressures by using the εv-q/p curve. Along with the increase of confining pressure, yield deviatoric stress qy and yield spherical stress py present logarithmic relationship. Besides, the strength parameters, elastic modulus K and G of intact loess, are obtained, which are benefit for loess projects design. 展开更多
关键词 yield stress compression testing failure model Middle pleistocene Epoch loess
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A New Mid Early Pleistocene Mammalian FaunaDiscovered in Choukoutien,China and Its Application in Biostratigraphy 被引量:3
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作者 Cheng Jie(Department of Geology and Mineral Resources, China University of Geosciences,Beijing 100083)Cao Boxun(Faculty of Earth Sciences, China University of Geosciences,Wuhan 430074)Tian MingZhong(Department of Geology and Mineral Resources, China Unive 《Journal of Earth Science》 SCIE CAS CSCD 1995年第1期41-47,120,共8页
This paper deals with a new Early Pleistocene micromammalian fauna found in Choukonden (Zhoukoudian) and its application in biostratigraphy.The new locality (east cave ), discovered in 1985,is located on the north slo... This paper deals with a new Early Pleistocene micromammalian fauna found in Choukonden (Zhoukoudian) and its application in biostratigraphy.The new locality (east cave ), discovered in 1985,is located on the north slope of the Taipingshan Hill, about 2 km northeast of the Loc.1 in Choukoutien and is about 140-150m in altitude. At this locality,abundant fossil mammals are found in thick cave-fissure deposit. This fauna comprises 30mammalian taxa. Based on the comparison of the fauna, as Well as the sporo-pollen, climate events and paleomagnetic polarity section with those in other areas,we come to the conclusion that the sediments (Taipingshan Formation) in east cave were formed during the Period about from 1.67 Ma B. P. to 0.97 Ma B. P., and the fauna is about 1.20 Ma B. P. in ags. 展开更多
关键词 mid Early pleistocene micromammalian fauna BIOSTRATIGRAPHY Choukoutien.
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DESERTIZATION OF THE CONTINENTAL SHELF OF CHINA IN THE LATER STAGE OF LATE PLEISTOCENE 被引量:2
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作者 赵松龄 李国刚 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1990年第4期289-298,共10页
In the later stage of Late Pleistocene, global climate entered into the climax period of Wurm when temperature decreased remarkably and glaciers developed. Information from the East China Sea also confirm that the sea... In the later stage of Late Pleistocene, global climate entered into the climax period of Wurm when temperature decreased remarkably and glaciers developed. Information from the East China Sea also confirm that the sea level fell by at least 130 m at that time (Emery, 1968). The Bohai Sea and Yellow Sea at the climax period were totally exposed, while the East China Sea and South China Sea shelf regions were exposed partly. The exposed shelf area exceeded 1 million km2 and became a salty desert where land plants could not survive. Such were the conditions which led to the desertization of the shelf region.Eolation was the major exogenetic force not only on land but also on the shelf region in the ice age. At the climax period of Wiirm, the northern part of China developed thick layers of loess deposits. The shelf region at that time had similar climatic conditions and sediments. Because the shelf region was not protected by vegetation in the ice age, intensive wind storms remoulded the primarily 展开更多
关键词 SHELF pleistocene vegetation exposed DESERT Bohai CLIMATIC LOESS Yellow thick
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