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31.
第四纪气候事件的孢粉记录 总被引：6，自引：0，他引：6
通过总结我国不同区域现有孢粉资料,发现第四纪孢粉植物群的演化序列中明显地存在与演化趋势和周期不符的孢粉植物群事件。归纳起来有三种类型：延续时间约万年的孢粉植物群突变事件;延续时间数千年的孢粉植物群贫乏事件和延续时间几百年的孢粉植物群颤动事件。突变事件有４起：Ｂｅｔｕｌａ－Ａｒｔｅｍｉｓｉａ事件（２．５ＭａＢ．Ｐ．）;Ａｒｔｅｍｉｓｉａ－Ｇｒａｍｉｎｅａｅ事件（１．４ＭａＢ．Ｐ．）;Ｅｐｈｅｄｒａ－ 相似文献
32.
Sub‐basaltic sediments in the Mt Royal Range area, studied with a view to testing models of the evolution of the Eastern Highlands, have yielded a palynoflora ascribed to the Paleocene Lygistepollenites balmei Zone. The palynofloras come from a core sampling sediment which accumulated when a stream was dammed by basalt. This is the first reported occurrence of a definite Paleocene flora in the Eastern Highlands region. Basalt in the vicinity of the core gave a K‐Ar age of 54.1 ± 0.3 Ma. The discrepancy between the pollen age and the K‐Ar date is considered to be relatively minor. 相似文献
33.
The palynological assemblage from Wulaga dinosaur site in Jiayin from southeastern Zeya-Bureya Basin was studied. The high content of pteridophytes spores is characteristic for this assemblage. The further characters are in decrease of abundance-tricolpate pollen, Ginkgocycadophytus, pollen of Taxodiaceae, Cupressaceae and Taxaceae （TCT） , bisaccate pollen of Pinaceae, and triporate pollen. The bone-bearing burials of Wulaga dinosaur site formed under conditions of vast swampy river valley covered by ferns and taxodialeans. Tricolpate pollen, produced by plants, close to those of Platanaceae, Fagaceae, Betulaceae, and Juglandaceae, counts in favor of valley river open canopy forests. 相似文献
34.
基于新疆拜城地区下白垩统舒善河组发现的29属48种孢子花粉化石的研究,建立了研究区早白垩世早期孢粉植物群。舒善河组孢粉植物群以松杉目掌鳞杉科的优势和真蕨目海金沙科的繁茂为特征。根据孢粉植物群的特征,探讨了该区早白垩世早期古生态、古气候和古地理特征。掌鳞杉科植物是耐干旱和耐热的乔木和灌木,当时掌鳞杉科和海金沙科植物在亚热带气候下都很常见,表明拜城地区早白垩世早期古气候属于亚热带干燥型,气候炎热干旱。孢粉植物群的生物多样性和植物地理分布明显的分带性显示该区早白垩世早期古地理具有复杂多样的景观,包括山峦、山谷、山涧、河流三角洲沼泽和沼泽湿地等。 相似文献
35.
E. P. Lelikov I. B. Tsoy T. A. Emel’yanova E. P. Terekhov N. G. Vashchenkova N. K. Vagina O. L. Smirnova V. D. Khudik 《Russian Journal of Pacific Geology》2008,2(2):99-109
Results of geological research conducted by the Pacific Oceanological Institute of the Far East Division of the Russian Academy of Sciences and the Institute of Oceanology of the Russian Academy of Sciences on the submarine Vityaz Ridge during Cruise 37 of R/V Akademik M.A. Lavrentyev in 2005 are discussed. Various rocks constituting the basement and sedimentary cover of the ridge were dredged in three areas of the ridge. Based on isotope geochronology, petrogeochemical, petrographic, and paleontological data and comparison with similar rocks available from the adjacent land and Sea of Okhotsk, they are subdivided into several age complexes. Late Cretaceous, Eocene, Late Oligocene, Miocene, and Pliocene-Pleistocene complexes are defined among the igneous rocks, while volcanogenic-sedimentary rocks are united into Late Cretaceous-Early Paleocene (late Campanian-Danian), undivided Paleogene (Paleocene-Eocene?), Oligocene-early Miocene, and Pliocene-Pleistocene complexes. The obtained data on the age and formation settings of the defined complexes made it possible to reconstruct the geological evolution of the central Pacific slope of the Kurile island arc. 相似文献
36.
关于南京猿人生存时期的气候环境讨论 总被引：12，自引：3，他引：9
根据南京猿人产地（葫芦洞）中的孢粉分析结果推测当时气温明显比现在低,可能相当于一次冰期。该结论与南京猿人共生的哺乳动物化石群的性质是一致的。 相似文献
37.
渭河谷地晚新生代地表环境巨变的孢粉记录 总被引：3，自引：0，他引：3
本文在总结渭河谷地２０多个孢粉剖面的基础上,依据古地磁资料确定其时代,并在空间和时间上进行孢粉组合对比,从而建立了１０个区域孢粉组合带。由此提出３．５ＭａＢＰ以来孢粉植物群的演化经历了５个阶段：由阔叶林－－针叶林－－森林草原与草原－－森林草原与茺漠草原－－草原－－森林草原与草原。这５个阶段标志着地表环境系统发生巨大变革,变革时间为２．５ＭａＢＰ,２．０ＭａＢＰ,１．４／１．６ＭａＢＰ和０．８ＭａＢ 相似文献
38.
Sangheon Yi Chang-Gyun Han Keun-Chang Oh In Sun Seo Dongwook Kim Jaeyoung Lee Min Han Hanwoo Choi Jaesoo Lim Sujeong Park Chang-Pyo Jun Taesop Cho 《第四纪科学杂志》2022,37(1):100-113
We comprehensively analyzed sediments obtained from an archeological excavation. A trench sediment profile of Maedun Cave (MC), South Korea, was analyzed geoarchaeologically. Multi-proxy analyses (palynomorphs, grain size, magnetic susceptibility, animal bones and artifacts) reflected the vegetation, hydroclimate and lives of prehistoric people at Marine Isotope Stage (MIS) 3 (ca. 40–30k cal a bp ) in the early Late Paleolithic. The palynoflora consisted of pollen and non-pollen palynomorphs. Under the air-circulation system in the cave, anemophilous pollen flowed in during the day, whereas waterborne pollen and spores, and freshwater algae, were transported by flooding during the summer monsoon rainy season. Mixed conifer and deciduous broad-leaved forest with an understory of pteridophytes flourished around the north-east central Korean Peninsula during MIS 3. Freshwater algae and grass pollen records may reflect precipitation intensity. It is assumed that they had flowed in during flooding caused by high precipitation during the enhanced East Asian summer monsoon, corresponding to Dansgaard–Oeschger (D/O) events 5 and 8 of δ18O GISP2 and Hulu Cave. The prehistoric people hunted herbivorous animals in the area around MC and sheltered inside it seasonally. They also used the grains of oats growing near the dwelling as a source of food. 相似文献