首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 31 毫秒
1.
This review presents the themes of a special issue dealing with environmental scenarios of human evolution during the Early Pleistocene (2.6–0.78 Ma; MIS 103-MIS 19) and early Middle Pleistocene (0.78–0.47 Ma; MIS 19-base of MIS 12) within the western Palaearctic. This period is one of dramatic changes in the climates and the distribution of Palaearctic biota. These changes have played their role in generating adaptive and phyletic patterns within the human ancestry, involving several species such as Homo habilis, “Homo georgicus”, Homo erectus, Homo antecessor and Homo heidelbergensis. In the archaeological record, these species include the Oldowan (Mode 1) and Acheulian (Mode 2) lithic technologies. Taphonomic considerations of palaeoecological research in hominin-bearing sites are provided and evaluated. Syntheses are provided for north Africa, western Asia, the Mediterranean Basin, Britain, and continental Europe. Palaeoenvironmental reconstructions based on multidisciplinary data are given for Ain Boucherit, Ain Hanech and El-Kherba in Algeria, Dmanisi in Georgia, Atapuerca, Cueva Negra, and the Orce Basin in Spain, Monte Poggiolo and Pirro Nord in Italy, Pont-de-Lavaud in France, and Mauer in Germany. The state of the art with the Out of Africa 1 dispersal model is reviewed. A source-sink dynamics model for Palaeolithic Europe is described to explain the morphological disparity of H. heidelbergensis (we will sometimes use the informal name “Heidelbergs”) and early Neanderthals. Other aspects debated here are the selective value of habitat mosaics including reconstructions based on mammal and avian databases, and the role of geological instability combined with topographic complexity. This review is completed by addressing the question of whether the appearance of evolutionary trends within hominins is concentrated in regions of highest worldwide biological diversity (biodiversity hotspots). It is concluded that the keys for the activation of evolutionary change in hominins may have been geological instabilities, and a shifting physiographical heterogeneity combined with high biodiversity and ecological interaction.  相似文献   

2.
Since chronometric data comparable to that available from the late Cenozoic succession of East Africa have not, and probably cannot be obtained in southern Africa, faunal dating methods retain their traditional significance in the latter area. Five successive late Cenozoic mammal ages, the Namibian, Langebaanian, Makapanian, Cornelian, and Florisian have been proposed as a framework for discussions relating to the chronology of southern African mammalian faunas. The Namibian fauna is poorly known, but is evidently of Miocene age. It is not discussed in this paper. The Langebaanian fauna is well known only from the prolific occurrence at the type site of Langebaanweg and is Pliocene in age. Makapanian faunas are best represented at the Transvaal Australopithecine sites and probably overlap the Plio-Pleistocene boundary. The Cornelian fauna is not as well known as others, the largest assemblage having been recorded from Elandsfontein, although this assemblage is one which is unfortunately temporally heterogeneous. Florisian faunas have been recovered from a relatively large number of localities, including several for which there are radiometric dates. The recorded southern African fossil Carnivora are listed and the local evolution of this group is discussed in terms of the mammal age chronology. It is concluded that secure faunal dating of individual fossil occurrences is enhanced by an appreciation of the nature of changes undergone in evolutionary lineages, while an uncritical knowledge of recoreded taxa is less useful.  相似文献   

3.
During the latest Cretaceous, distinct dinosaur faunas were found in Laurasia and Gondwana. Tyrannosaurids, hadrosaurids, and ceratopsians dominated in North America and Asia, while abelisaurids and titanosaurians dominated in South America, India, and Madagascar. Little is known about dinosaur faunas from the latest Cretaceous of Africa, however. Here, a new abelisaurid theropod, Chenanisaurus barbaricus, is described from the upper Maastrichtian phosphates of the Ouled Abdoun Basin in Morocco, North Africa on the basis of a partial dentary and isolated teeth. Chenanisaurus is both one of the largest abelisaurids, and one of the youngest known African dinosaurs. Along with previously reported titanosaurian remains, Chenanisaurus documents the persistence of a classic Gondwanan abelisaurid-titanosaurian fauna in mainland Africa until just prior to the end-Cretaceous mass extinction. The animal is unusual both in terms of its large size and the unusually short and robust jaw. Although it resembles South American carnotaurines in having a deep, bowed mandible, phylogenetic analysis suggests that Chenanisaurus may represent a lineage of abelisaurids that is distinct from those previously described from the latest Cretaceous of South America, Indo-Madagascar, and Europe, consistent with the hypothesis that the fragmentation of Gondwana led to the evolution of endemic dinosaur faunas during the Late Cretaceous.  相似文献   

4.
We analyzed published records of terrigenous dust flux from marine sediments off subtropical West Africa, the eastern Mediterranean Sea, and the Arabian Sea, and lake records from East Africa using statistical methods to detect trends, rhythms and events in Plio-Pleistocene African climate. The critical reassessment of the environmental significance of dust flux and lake records removes the apparent inconsistencies between marine vs. terrestrial records of African climate variability. Based on these results, major steps in mammalian and hominin evolution occurred during episodes of a wetter, but highly variable climate largely controlled by orbitally induced insolation changes in the low latitudes.  相似文献   

5.
This study presents data on the mineralogy and the metal content of dust deposited in Al Ain and Ras Al Khaimah, United Arab Emirates. The mineralogical compositions of the dust were determined using X-ray diffraction, and the results revealed that quartz is the dominant mineral, whereas calcite, dolomite, plagioclase, and serpentine were minor minerals. Two sampling sites were chosen from both Al Ain and Ras Al Khaimah. The concentrations of Fe, Zn, Cu, Cr, Pb, Cd, Ni, and Co in the sedimentation dusts samples of these sites were determined using inductively coupled plasma. The levels of most of heavy metal were generally below those determined in the other cities in the Middle East. The air enrichment factors for all the samples were analyzed, and the results indicated that Cd, Zn, Co, and Ni were highly enriched relative to their crustal ratios (to Fe) and correspond to substantial contribution of anthropogenic source of these metals. These metals mainly originate from the traffic emissions and industrial activities with contribution from natural sources. The average rates of deposition in Al Ain and Ras Al Khaimah were 193 and 972 mg m?2 day?1, respectively. These rates were higher than those of other regions.  相似文献   

6.
The Eocene rocks exposed in the Fayum Area, Egypt, are well known for their fossil vertebrates but in recent times the sharks and rays have been largely neglected. Extensive surface collecting, supplemented with bulk samples, has produced large collections from the Midawara, Gehannam, Birket Qarun and Qasr el-Sagha formations, spanning the Bartonian and Priabonian stages and from palaeoenvironments varying from open muddy shelf to very shallow estuarine systems. In total about 90 species of sharks and rays are recorded, many of them previously unrecognised, resulting in some of the most diverse fossil chondrichthyan assemblages known from the Tertiary. Teeth of these species suggest that they occupied a wide range of ecological niches from top predator to tiny benthic invertebrate feeder to planktivore. Many of the species are limited in their stratigraphical range and show potential to be used, at least locally, as biostratigraphical indicators for stratigraphically poorly constrained vertebrate sites elsewhere in North Africa. Distinctly different faunas from different sedimentary environments indicate a strong environmental control on the distribution of many species.  相似文献   

7.
R. Lee Lyman   《Quaternary Research》2008,70(3):426-432
For more than fifty years it has been known that mammalian faunas of late-Pleistocene age are taxonomically unique and lack modern analogs. It has long been thought that nonanalog mammalian faunas are limited in North America to areas east of the Rocky Mountains and that late-Pleistocene mammalian faunas in the west were modern in taxonomic composition. A late-Pleistocene fauna from Marmes Rockshelter in southeastern Washington State has no modern analog and defines an area of maximum sympatry that indicates significantly cooler summers than are found in the area today. An earliest Holocene fauna from Marmes Rockshelter defines an area of maximum sympatry, including the site area, but contains a single tentatively identified taxon that may indicate slightly cooler than modern summers.  相似文献   

8.
何心一  陈建强 《现代地质》1998,12(2):151-159
摘 要　 提出扬子区是奥陶纪、志留纪四射珊瑚的起源中心。早古生代扬子区最早出现的四射 珊瑚约有30属‚包括穿孔珊瑚类 Calostylis‚Yohophyllum‚扭心珊瑚类 Briantelasma‚Tunguse 提出扬子区是奥陶纪、志留纪四射珊瑚的起源中心。早古生代扬子区最早出现的四射 珊瑚约有30属‚包括穿孔珊瑚类 Calostylis‚Yohophyllum‚扭心珊瑚类 Briantelasma‚Tunguse- lasma‚包珊瑚类 Amplexoides‚Synamplexoides‚十字珊瑚类 Eostauria‚Ceriaster‚Stauria 以及 珊瑚约有30属‚包括穿孔珊瑚类 Calostylis‚Yohophyllum‚扭心珊瑚类 Briantelasma‚Tunguse lasma‚包珊瑚类 Amplexoides‚Synamplexoides‚十字珊瑚类 Eostauria‚Ceriaster‚Stauria 以及 泡沫珊瑚类 Rhizophyllum 等。它们在扬子区中奥陶世和早志留世地层迅速繁衍‚尔后扩散至 欧洲、北美和其他地区。扬子区晚奥陶世四射珊瑚群与北欧同期珊瑚有较高的相似性;而该 泡沫珊瑚类 Rhizophyllum 等。它们在扬子区中奥陶世和早志留世地层迅速繁衍‚尔后扩散至 欧洲、北美和其他地区。扬子区晚奥陶世四射珊瑚群与北欧同期珊瑚有较高的相似性;而该 区早志留世（包括 Wenlockian 阶）珊瑚群的生物古地理关系与西伯利亚、哈萨克斯坦有紧密联 欧洲、北美和其他地区。扬子区晚奥陶世四射珊瑚群与北欧同期珊瑚有较高的相似性;而该 区早志留世（包括 Wenlockian 阶）珊瑚群的生物古地理关系与西伯利亚、哈萨克斯坦有紧密联 系。扬子区早志留世珊瑚群与澳大利亚东部、北美东部同期珊瑚也有一定的相似性。 区早志留世（包括 Wenlockian 阶）珊瑚群的生物古地理关系与西伯利亚、哈萨克斯坦 系。扬子区早志留世珊瑚群与澳大利亚东部、北美东部同期珊瑚也有一定的相似性。  相似文献   

9.
A new multidisciplinary research program, started in 1981, provided new data on the stratigraphy, fauna, and human industries, as well as the first results on paleomagnetism and sedimentology, for the Ternifine site in Algeria, which yielded the earliest hominid remains known in North Africa. The fossils were deposited in a swamp or lake surrounded by a very open, dry environment. The lake was fed by artesian springs that raised the underlying Miocene sands. Although nothing suggests a camp or butchery site, we discovered the first undisputable bone artifact in this site, the earliest known in this part of Africa. According to paleontological data, 700,000 yr B.P. is a likely age for the Ternifine deposits, which is consistent with the paleomagnetic results.  相似文献   

10.
Timing of the Nihewan formation and faunas   总被引：2，自引：0，他引：2  
Magnetostratigraphic dating of the fluvio-lacustrine sequence in the Nihewan Basin, North China, has permitted the precise timing of the basin infilling and associated Nihewan mammalian faunas. The combined evidence of new paleomagnetic findings from the Hongya and Huabaogou sections of the eastern Nihewan Basin and previously published magnetochronological data suggests that the Nihewan Formation records the tectono-sedimentary processes of the Plio-Pleistocene Nihewan Basin and that the Nihewan faunas can be placed between the Matuyama-Brunhes geomagnetic reversal and the onset of the Olduvai subchron (0.78-1.95 Ma). The onset and termination of the basin deposition occurred just prior to the Gauss-Matuyama geomagnetic reversal and during the period from the last interglaciation to the late last glaciation, respectively, suggesting that the Nihewan Formation is of Late Pliocene to late Pleistocene age. The Nihewan faunas, comprising a series of mammalian faunas (such as Maliang, Donggutuo, Xiaochangliang, Banshan, Majuangou, Huabaogou, Xiashagou, Danangou and Dongyaozitou), are suggested to span a time range of about 0.8-2.0 Ma. The combination of our new and previously published magnetostratigraphy has significantly refined the chronology of the terrestrial Nihewan Formation and faunas.  相似文献   

11.
《Quaternary Science Reviews》2007,26(19-21):2526-2543
Occasional excavation of in situ and ex situ deposits at the formerly mined Gondolin paleocave system has yielded large and diverse samples of Plio-Pleistocene faunas, including isolated hominin and non-hominin primate remains. In 2003, new excavations into naturally decalcified, in situ sediments near the GD 1 datum point near the northwest corner of the cave system were undertaken. This paper describes the recovered faunal remains, taphonomy of the assemblage, and the geological and paleomagnetic context of the GD 1 deposits. The deposits represent a series of inter-stratified speleothem, in-washed sediments and talus deposits we suggest date to a time period prior to, and just after, the Olduvai normal-polarity event at around 1.7–1.8 Ma. Surface sediments and clasts were introduced into the cave by rain water runoff entering a vertically-oriented entrance that had formed along a rift in the area of GD 1. The faunal assemblage consists primarily of fragmentary diaphyseal fragments and isolated teeth. Taxonomically, the small collection of specifically identifiable bovid and equid fossils is generally consistent with remains previously excavated from in situ deposits in the Gondolin paleocave system (GD 2) and dated to around 1.8 Ma; however, the depositional histories of these two assemblages from Gondolin are remarkably different. The preservation and relative proportions of recovered skeletal elements at GD 1 is consistent with these materials having been initially accumulated outside the karstic system near the vertical cave entrance, and then later hydrologically sorted and deposited inside the cave. The sporadic to continuous water flow into the northwest corner of the cave system during the Pleistocene gradually decalcified the excavated fossilbearing breccias and further modified the composition and spatial distribution of the fossil assemblage by introducing potentially younger deposits and skeletal materials. This study highlights the variation in taphonomic processes that can occur within a single cave system, and the complex pre- and postdepositional geological and hydrological processes that can influence the taphonomic history of South African Plio-Pleistocene karstic fossil assemblages.  相似文献   

12.
Throughout the Neogene, the faunas and floras in Africa recorded global climatic changes. We present an overview of Neogene desertification in Africa by tracing stable isotopes in eggshells and mammalian enamel, by faunal (changes in hypsodonty, etc.) and floral changes in sequences at the latitudinal extremities of the continent and the equator. This work reveals that desertification started in the southwest ca 17–16 Ma, much earlier than the region of the present-day Sahara (ca 8–7 Ma) and long before the deserts in East Africa (Plio-Pleistocene). A consequence of this history is that animals and plants inhabiting the South of the continent had a long period of time in which to adapt to arid, unstable climatic conditions. When parts of East Africa became arid during the Late Miocene and Plio-Pleistocene, several of these lineages expanded northwards and occupied developing arid niches before local lineages could adapt. Several of the latter became extinct, while others withdrew westwards as the tropical forest diminished in extent. It is proposed that the history of desertification in Africa was related to that of the polar ice caps (Antarctic, Arctic).  相似文献   

13.
The Chouichia and Ain el Bey copper veins that occur in the Eastern Atlas fold belt in northwestern Tunisia, are hosted in Upper Cretaceous-Paleogene sedimentary sequences in a regional transcurrent shear zone. Paragenetic assemblages were formed during four distinct stages all of which are separated by fracturing and brecciation: Stage 1 consists of low temperature siderite (160–180 °C) formation in association with pyrite, including framboidal pyrite and marcasite. Stage 2 includes pseudomorphing of marcasite by As-rich pyrite and arsenopyrite, and formation of chalcopyrite at higher temperatures (200–300 °C) from S-rich, Fe-Cu-bearing fluids; As contents in individual pyrite and arsenopyrite crystals increase markedly in the rims relative to the centers, thus indicating non-equilibrium conditions. Stage 3 involves fracturing and brecciation predating deposition of enargite, luzonite and tennantite at Ain el Bey, and famatinite and tetrahedrite at Chouichia, from As-Sb-Bi-bearing oreforming fluids; tennantite-tetrahedrite series exhibit iron and copper-excess replacements in tetrahedral sites interrelated with Cu-Fe interactions (electron transfer). In Stage 4 fracturing was followed by calcite formation in voids. Comprehensive data was obtained from scanning electron microprobe (SEM) and microprobe chemical analyses of minerals, geothermometry using sulfur isotopes, As contents in arsenopyrite crystals and fluid inclusions in siderite and calcite, support an input of magmatic hydrothermal ore-forming fluids, although contamination by sedimentary sulfur were also identified.  相似文献   

14.
The Ain Turck (Bouira) landslide, in north-center Algeria, is one of the numerous instabilities recorded along the Lakhdaria-Bouira section of the 1200-km-long east-west Algerian highway. The locality of Ain Turck is known for its unstable slopes characterized by a very rough morphology with steep slopes (20 to 25%). This slide threatens the inhabitants of the Ibournanen village, located down the unstable slope, where parts of some houses have fallen into ruin, while others are cracked. It is characterized by an active movement extending over a more or less important slope, of the order of a hundred meters. The land mobilized by this movement corresponds to the layer of shale clays and clays overlaid by a backfill, placed there following the east-west highway works. Geological, geomorphologic, and geotechnical analysis allows determining the soil instability probably related to earthworks during the construction of the highway section a few years earlier, followed by a particularly rainy season in 2012. Acquisitions of ambient seismic noise and H/V ratio processing, as well as the acquisition of an electrical resistivity profile at the instability site, have reinforced our preliminary interpretations of depth and geometry of the sliding surface.  相似文献   

15.
A review on the position of the Pliocene-Pleistocene boundary is presented. Uncertainties about the Calabrian stratotype and mammal faunas ill relation to absolute datings are discussed. In the North Sea basin and elsewhere a marked cold stage, the Praetiglian, began about 2.5 million years ago. It caused a partial extinction of the flora, which in Italy too is distinctly represented in fresh-water as well as marine deposits. In the latter deposits, the extinction level coincides with the base of the Calabrian. The same type of extinction occurs at the base of the Villafranchian faunal sequence dated between about 2.5 and 3.1 million year-s ago. The Calabrian base is therefore most probably at about 2.5 m.y., not at 1.8 m.y. as previously thought. The 1948 Recommendation on the position of the Plio-Pleistocene boundary is still considered valid.  相似文献   

16.
We sampled 150 sites in fine-grained Plio-Pleistocene sediments of the Palm Springs and Imperial Formations. Sampling was confined to 3000 m of stratigraphically continuous section containing abundant vertebrate fossil remains of the Vallecito Creek, Arroyo Seco, and Layer Cake local faunas of the Irvingtonian and Blancan Land Mammal Ages. The magnetic stability of these sediments was sufficient to delineate the magnetic stratigraphy, which ranges from below the Cochiti event at the base, to the Matuyama reversed magnetic epoch at the top of the section. Eight faunal events are placed relative to the magnetic polarity sequence. They are cf. Pliohippus extinction, Geomys appearance, cf. Equus appearance, Tremarctos appearance, Hypolagus extinction, cf. Odocoileus appearance, Smilodon and ? Euceratherium appearance. The latter two faunal events characterize Irvingtonian Land Mammal Age. The transition from the Blancan to Irvingtonian Land Mammal Age occurs in the lower Matuyama magnetic epoch close to the Pliocene-Pleistocene boundary. The appearance of European migrants during the lower Matuyama magnetic epoch indicates that the Bering land bridge was exposed for animal migration between Europe and North America at this time.  相似文献   

17.
One hundred and thirty-six species, representing 67 genera have been recorded from the late Jurassic-Maastrichtian marine sediments of South Africa. The faunas show a major dichotomy across a regionally-developed late Cenomanian-early Coniacian hiatus with the Portlandian-Cenomanian Cytheruridae/Progonocytheridae/Schizocytheridae dominated faunas being replaced in the Coniacian by Trachyleberididae/Brachycytheridae/Schizocytheridae dominated faunas. Comparison with other Gondwanide localities shows that the two South African basins from which ostracods have been described (Outeniqua and Natal/Zululand) formed part of a Callovian-Cenomanian South Gondwana ostracod province that stretched from the Neuquen Basin of Argentina to Madagascar/Tanzania/Kutch and west Australia. The most characteristic and cosmopolitan forms within this province belong to the Majungaella/Amicytheridea/Progonocythere group, along with Arculicythere in the Aptian-Cenomanian.In Tanzania, (the only locality of the old South Gondwana province where the succession is complete) these assemblages are replaced in the Turonian by the influx of Brachycythere, and Cythereis and various other trachyleberids. Changes of a similar nature are seen whenever marine sedimentation resumed after the local “mid” Cretaceous hiatus (South Africa, India, Argentina). Argentina differs in not having Brachycythere, whose rapid appearance in the West Indian Ocean basin soon after its earliest record in Brazil, is attributed to the destruction of the barrier at the eastern end of the Walvis Ridge/Rio Grande Rise in late Cenomanian or early Turonian times. Despite this common element with Brazil and West Africa, the South African Coniacian to Maastrichtian faunas are closer to those of Tanzania and Australia than they are to either Argentina or Brazil/West Africa. In Zululand they show evidence of a steady increase in water depth, leading to the establishment of progressively more diverse cytheracean populations, with a particularly large increase across the Santonian/Campanian boundary.  相似文献   

18.
Throughout the Cenozoic, the North American mammalian fauna has been enriched by the appearance of new taxa originating on different continents. During most of the Tertiary, the primary source area of these new taxa was Eurasia with dispersal across some version of the Bering Land Bridge. In the late Pliocene (Blancan) ca. 2.5 mya, the creation of the Panamanian Land Bridge permitted the northward dispersal of species of South American origin including ground sloths. One of these sloths was “Glossotherium” chapadmalense, which in turn gave rise to the Pleistocene species Paramylodon harlani. Mammoths first appear in North America at the beginning of the Irvingtonian ca. 1.9 mya. Despite originating on two different continents, the two species are often found together in North American Pleistocene faunas and shared a common habitat. Both of these lineages are commonly interpreted as grazers, indicative of open grassland habitat, and both of these exotic species shared this habitat with North American endemic species such as horses, also interpreted as grazers. Despite their association in North American faunas, mammoths did not disperse into South America and mylodont sloths were unable to disperse into Eurasia. This suggests there were some aspects of their ecology they did not have in common and there existed a limited zone of conditions that permitted them to share common habitat. There is no evidence that the appearance of either species in North America resulted in the extinction of any native species. The question is how these different species, immigrants and endemics, were able to avoid competition, coexist, and become integrated into a single fauna, thus enriching the overall North American Pleistocene fauna.  相似文献   

19.
A spinel ± amphibole ± feldspar bearing Iherzolites, a spinel ± amphibole ± feldspar bearing harzburgites, and a spinel ± amphibole ± phlogopite bearing wehrlites are metasomatized peridotitic mantle xenoliths from Ain Temouchent volcanic complex (North-West Algeria). These xenoliths are metamorphic/deformed rocks with a strong planar fabric typical of mantle tectonites. The wehrlites are not the result of a simple model of partial melting. The spinel ± amphibole ± feldspar bearing harzburgites and lherzolites exhibit asymmetric concave-shaped REE patterns. These indicate that an earlier partial melting event was followed by metasomatic processes. The wehrlites have higher REE concentrations and LREE/HREE fractionations, indicating a sequential evolution of wehrlites from previous refractory material with melting as an addition process. This process reflects the interaction of the lithospheric mantle beneath the Ain Temouchent area with basaltic melt. Metasomatism is expressed by the formation of amphibole, phlogopite, and increased abundances of clinopyroxene at the expense of orthopyroxene, in lherzolite and harzburgite. In the Ain Temouchent area, metasomatizing agents are Na-alkali silicates. The similarities observed between the glasses studied in this paper, and the basaltic host rocks of the Ain Temouchent area, may suggest a common mantle source, or with chemical similarities but with relatively different evolutions pathways. The formation of glass in wehrlites from the Ain Temouchent area has an origin formed by the breakdown of amphibole or phlogopite as a result of decompressional melting and production of silica-undersaturated glasses. The glass reacts with essentially orthopyroxene to produce silica-rich glasses. This study has contributed to highlighting a relationship between glass, and the processes that caused the formation of metasomatic phases.  相似文献   

20.
Several Gigantopithecus faunas associated with taxonomically undetermined hominoid fossils and/or stone artifacts are known from southern China. These faunas are particularly important for the study of the evolution of humans and other mammals in Asia. However, the geochronology of the Gigantopithecus faunas remains uncertain. In order to solve this problem, a program of geochronological studies of Gigantopithecus faunas in Guangxi Province was recently initiated. Chuifeng Cave is the first studied site, which yielded 92 Gigantopithecus blacki teeth associated with numerous other mammalian fossils. We carried out combined ESR/U-series dating of fossil teeth and sediment paleomagnetic studies. Our ESR results suggest that the lower layers at this cave can be dated to 1.92 ± 0.14 Ma and the upper layers can be dated to older than 1.38 ± 0.17 Ma. Correlation of the recognized magnetozones to the geomagnetic polarity timescale was achieved by combining magnetostratigraphic, biostratigraphic and ESR data. The combined chronologies establish an Olduvai subchron (1.945–1.778 Ma) for the lowermost Chuifeng Cave sediments. We also analyzed the enamel δ13C values of the Gigantopithecus faunas. Our results show that southern China was dominated by C3 plants during the early Pleistocene and that the Gigantopithecus faunas lived in a woodland-forest ecosystem.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号