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1.
黑龙江省东部鸡西盆地早白垩世穆棱组植物化石新材料   总被引:4,自引:0,他引:4  
杨小菊 《古生物学报》2003,42(4):561-584
系统描述了最近采集的穆棱组植物化石22属23种,其中的两种被子植物叶化石均为具原始被子植物叶特征的小型叶,在该植物群中尚属首次发现。运用扫描电镜(SEM)等方法对其中的Tyrmia sp.,Nilssoniopteris sp.,Ginkgoites cf..sibirica,.Sphenobaiern sp.,Elatocladus manchurica等化石的叶角质层进行了研究。据已有的资料统计,穆棱组迄今已知有化石植物31属38种。该植物群以真蕨类占据绝对优势,裸子植物也相当丰富,其中的大多数种类主要见于早白垩世,穆棱组的地质时代应属早白垩世巴列姆期或巴列姆-阿普梯早期。植物组合中以丰富的热带及亚热带型植物为主要特点,未发现针叶类型的植物,说明早白垩世穆棱组沉积时,该地区的气候温暖湿润;另一方面,落叶的银杏类和松柏类,以及裸子植物木化石中具有清楚的生长轮,又说明该地区的古气候存在着季节变化。该植物群属于早白垩世西伯利亚植物区或加拿大-西伯利亚植物区。  相似文献   

2.
Sedimentary sequences in the Columbia Plateau region of the Pacific Northwest ranging in age from 16–4 Ma contain fallout tuffs whose origins lie in volcanic centers of the Yellowstone hotspot in northwestern Nevada, eastern Oregon and the Snake River Plain in Idaho. Silicic volcanism began in the region contemporaneously with early eruptions of the Columbia River Basalt Group (CRBG), and the abundance of widespread fallout tuffs provides the opportunity to establish a tephrostratigrahic framework for the region. Sedimentary basins with volcaniclastic deposits also contain diverse assemblages of fauna and flora that were preserved during the Mid-Miocene Climatic Optimum, including Sucker Creek, Mascall, Latah, Virgin Valley and Trout Creek. Correlation of ashfall units establish that the lower Bully Creek Formation in eastern Oregon is contemporaneous with the Virgin Valley Formation, the Sucker Creek Formation, Oregon and Idaho, Trout Creek Formation, Oregon, and the Latah Formation in the Clearwater Embayment in Washington and Idaho. In addition, it can be established that the Trout Creek flora are younger than the Mascall and Latah flora. A tentative correlation of a fallout tuff from the Clarkia fossil beds, Idaho, with a pumice bed in the Bully Creek Formation places the remarkably well preserved Clarkia flora assemblage between the Mascall and Trout Creek flora. Large-volume supereruptions that originated between 11.8 and 10.1 Ma from the Bruneau-Jarbidge and Twin Falls volcanic centers of the Yellowstone hotspot in the central Snake River Plain deposited voluminous fallout tuffs in the Ellensberg Formation which forms sedimentary interbeds in the CRBG. These occurrences extend the known distribution of these fallout tuffs 500 km to the northwest of their source in the Snake River Plain. Heretofore, the distal products of these large eruptions had only been recognized to the east of their sources in the High Plains of Nebraska and Kansas.  相似文献   

3.
四川新龙晚三叠世植物   总被引:1,自引:0,他引:1  
本文报道四川省新龙地区晚三叠世植物(包括英珠娘阿组及喇嘛垭组)29属48种。在这植物群中,真蕨植物占优势(8属15种),其中又以扇蕨科,合囊蕨科和紫萁科植物占显要地位,苏铁类植物次之,银杏类和松柏类植物比较丰富,种子蕨类植物出现了叉羽叶和鳞羊齿等。其组合特征与云南一平浪组、四川须家河组植物群,湘赣地区,箐河以及藏东地区晚三叠世中晚期植物群极为相似。与日本成羽,越南东京和东格陵兰等地晚三叠世植物群也比较接近,所属地质时代大致相当,应属于三叠世考依卜中——晚期。指示的气候属热带——亚热带。  相似文献   

4.
本文描述了贵州金沙岩孔镇长岩沟下寒武统(纽芬兰统—寒武系第2统)牛蹄塘组底部黑色页岩中呈碳质薄膜保存的宏观藻类化石,共3属3种:美丽遵义藻Zunyiphyton pereleganus Yang et Zhao,1999,云南中华细丝藻Sinocylindra yunnanensis Chen et Erdtmann,1991,文德带藻(未定种)Vendotaenia sp.。该组合中主要分子是Zunyiphyton pereleganus和Vendotaenia sp.,它们也是遵义牛蹄塘组宏观藻类组合中最主要的分子。而遵义牛蹄塘组宏观藻类组合的另一特征分子贵州约克那斯藻Yuknessis guizhouensis及底栖固着型藻束状陡山沱藻Doushantuophyton comet在金沙岩孔牛蹄塘组宏观藻类化石组合中未见,说明产于浅水台地的牛蹄塘生物群宏观藻类组合既具有广泛的一致性也具有一定的差异性。  相似文献   

5.
《Palaeoworld》2020,29(3):590-605
A unique Early Jurassic flora from the Schitukhe Formation of South Primorye, Russia is further studied, with newly collected materials. The flora is composed of over 50 taxa. It is dominated by ferns (Dipteridaceae, Marattiaceae, etc.), cycads (Pterophyllum, Nilssonia, Ctenis, Taeniopteris, etc.), conifers (Cycadocarpidium, Podozamites, etc.), and other seasonally deciduous gymnosperms (Czekanowskiales, Ginkgoales, etc.), showing a special flora living in an ecotone zone between the Palaeofloristic realms of Siberian Flora and Euro-Sinian Flora in the East Asia during the early Early Jurassic. The flora is compared with its coeval floras from China and Japan. A new species Cycadocarpidium pacificum n. sp. is reported. The age of the Schitukhe flora is constrained by the marine mollusca fossils yielded in the sandwich marine beds of the Schitukhe Formation, as the Hettangian–Sinemurian.  相似文献   

6.
The genus Thinnfeldia was seldom reported in former geological literature from Hubei. In the present paper, the following fossil plants of Thinnfeldia from Hubei are collected for the first time: Thinnfeldia elegans (sp. nov.), T. nanzhangensis (sp. nov.), T. yuananensis (sp. nov.), from Late Triassic Jiuligang Formation of the Jingmen-Dangyang Basin. It is interesting to point that the Jiuligang flora has transational characters between Yanchang flora of North China and Anyun flora of South China of Late Triassic.  相似文献   

7.
Silicified coniferous wood was collected from the Lanqi Formation (late Middle Jurassic in age) at Shebudaigou Village, Liaoning Province, China. Three taxa are identified, namely Pinoxylon dacotense Knowlton, Xenoxylon phyllocladoides Gothan, and Araucariopitys sp. Based on these new data, and those of other fossil plants reported previously from the same formation, we consider the climate during the deposition of the Lanqi Formation was subtropical, humid and seasonal. In this respect the Lanqi flora differs from the coeval Shimengou and Longmen floras from North China. The Longmen flora was deposited during more humid, subtropical conditions, while the Shimengou Formation indicates that the climate was warm temperate and dry. Our data would suggest that the Late Jurassic climatic pattern was initiated as early as the late Middle Jurassic.  相似文献   

8.
新疆准噶尔盆地白杨河中侏罗世植物化石新材料   总被引:3,自引:0,他引:3  
苗雨雁 《古生物学报》2005,44(4):517-534
系统描述了准噶尔盆地西北缘白杨河地区西山窑组植物化石15属25种,首次在新疆地区发现侏罗纪真蕨类重要分子Coniopteris hymenophylloides的原位孢子及其孢子囊群,并对Phoenicopsis ( Phoenicopsis) an-gustifolia的叶角质层进行了研究。白杨河地区西山窑组迄今已知植物化石24属39种,以富含蕨类、茨康类、银杏类及松柏类,少见苏铁类等为特征,属于较为典型的内陆型、温带或暖温带植物群;其时代为中侏罗世,且可能为中侏罗世早期。该植物群应属于欧亚大陆早、中侏罗世植物地理区系中的西伯利亚区,反映了温暖潮湿、具季节性变化、并有利成煤的环境。  相似文献   

9.
From the Upper Pechelbronn Formation (Latdorfian, Lower Oligocene) of Merkwiller-Pechelbronn (France, Alsace) a well preserved charophyte flora with numerous mass occurrences is presented. Two new species are described:Chara praemicrocera andSphaerochara pygmaea. The sequence seems to have been deposited under almost pure limnic conditions, according to ostracod data. Biostratigraphical correlations between the Upper Pechelbronn Formation, theStephanochara, pinguis zone (Riveline 1986) and the Mammalian reference level MP 21 (Schmidt-Kittler 1987) are postulated.  相似文献   

10.
《Palaeoworld》2020,29(4):706-714
A new species Pleuromeia shaolinii Zhang et Wang n. sp. was established under the family Pleuromeiaceae, based on eight specimens of stems and leaves, cones, rhizophores, and adventitious roots that were recently collected from the Middle Triassic Linjia Formation in Benxi, Northeast China. P. shaolinii n. sp. is similar to the type species P. sternbergii, in the morphology of the stem and rhizophore, but differs from it by the transversely rounded sporophylls organized in a heterosporous cone, and the two conspicuous triangular scars present on both sides of the vascular bundle scar. The Linjia flora, an only reliable Middle Triassic flora in Northeast China, was discovered 40 years ago. Although the Linjia Formation can be compared with the Middle Triassic Ermaying Formation from another area of the North China plate, its age was questionable due to the absence of the Early to Middle Triassic index fossil Pleuromeia. Based on the flora similarity, the zircon dating, lithologic characteristics, presence of a disconformity, and the occurrence of the Middle Triassic–Early Cretaceous insect fossil Sogdoblatta, the age of the Linjia Formation can be confirmed as Middle Triassic. The new species not only supplements our knowledge in biology and taxonomy of Pleuromeia, but also supports the Middle Triassic age assignment of the Linjia flora.  相似文献   

11.
Coniopteris magnifica sp. nov., Ctenophyllum chenyuanense sp. nov., C. laxilobum sp. nov., Mironeura dakengensis Zhou, are derived from the Xiangxi Formation (s.s.), Western Hubei. According to the aspect and characteristic of the Xiangxi flora, author considers the Xiangxi Formation as Early Jurassic in age. In this paper, the relative problem between the coal-bearing and the fossil plants is briefly discussed also.  相似文献   

12.
开鲁盆地白垩系发育,至今已有200余口探井钻遇到上白垩统,其中嫩江组滨浅湖相沉积地层厚度稳定,分布广泛,含较丰富的孢粉化石。通过对嫩江组孢粉化石的系统研究,建立了以Schizaeoisporites-BeaupreaiditesLythraites为代表的孢粉组合。孢粉组合和岩石组合的对比表明,开鲁盆地缺失松辽盆地嫩江组中上部地层。根据沉积特征和孢粉植物群面貌,对古植被、古气候和古环境进行了讨论,认为本区晚白垩世处于东北中生孢粉植物区南缘,孢粉植物群具有过渡性质,反应了偏干的暖温带—亚热带气候特征。  相似文献   

13.
吉林龙井渐新世三合植物群   总被引:2,自引:1,他引:1  
描述三合植物群24种(归17科22属),其中17已知种,1新种(Zizyphus orbitofolia)和6未定种。此化石植物群包含蕨类植物1种1种,裸子植物5属5种,被子植物16属18种,其中有2形态属,其余全归现代属。这个植物群的物种数量虽不多,但其多样性是很明显的。植物群中壳斗科有3属5种,是属种最多的科。其次杉科有3属3种,豆科2属2种,其余14科仅有1属1种。植物群中只有Sequoia、Fukienia和Palaeocarya是常绿植物,其余均属落叶植物,是一个针叶和落叶阔叶混交林。三合植物群的成分与朝鲜北部咸镜北道会宁植物群类似,属于渐新世。  相似文献   

14.
Neeru Prakash   《Palaeoworld》2008,17(3-4):253
The Jabalpur Formation of Jabalpur series, named after Jabalpur city in Central India, is exposed along the Narbada River, in Satpura Basin. The series is divided into the lower Chaugan and the upper Jabalpur stages. The Jabalpur beds occur between Mahadevas and Lametas at Mahadeva Hills, exhibit highest Gondwanan strata, and embody diversified flora. These beds also extend laterally to Bairam and Belkher areas in western part of central India. The highest diversity of the floral assemblage is recorded in the central portion of the basin (Sehora and Hasnapur) whereas the lowest diversity is recorded in Morand River, Parsapani and Tilaksindoor areas. The diversity in floral assemblage indicates the dominance of conifers and pteridophytes along with cycadophytes and certain pteridosperms. The palynofloral assemblage from this formation contains pollen and spores of bryophytic, pteridophytic and gymnospermic groups. The palaeovegetational diversity, biostratigraphic correlation and phytogeographic distribution of the Jabalpur flora are discussed in comparison with various coeval floras of Indian peninsula along with contemporaneous deposits of the other Gondwanan regions. The palaeogeographic analysis suggests that the flora was thriving as mixed vegetation during Early Cretaceous under seasonally hot and dry or alternating with wet and dry condition.  相似文献   

15.
This paper mainly deals with the Upper Cretaecous-Paleogene and the Neogene floras of Xizang. In 1974–1976. the Scientific Expedition Party of Academia Sinica discovered some fossilbearing beds from the Rikaze Group of Angreg district, the Jiuwu Formation of Douga district and the Menchi Formation of the Gandis Mountains. From these beds, leaf impressions of Eucalyptus angusta, E. geinitzi, E. oblongifolia, Ficus daphnoycnoides, F. stepheuseni, F. myrtifolia, Cassia fayattensis, C. marshalensis, Celastrus minor, Quereus orbicularis, Rhamnus menshigensis, Juglandites sinutus, Phrynium tibeticum Cyperacites of. haydenii and Typha sp. were obtained. Of which the genus Eucalyptus appears to be predominant. The geological age of this flora is assigned to Upper Cretaceous-Paleogene. It indicates that during this time the flora is mainly composed of evergreen broad-leaved trees thriving under a hot and wet climate. Fossils obtained from the Ye-Ma-Gou Formation of Gandis Mountains mainly consist of Populus balsamoides, P. latior, P. glandulifera, Salix sp. and Leguminosites sp. The age of this flora is assigned to Miocene, the fossils indicate that by that time deciduous broad-leaved trees were flourishing in that area. The Miocene of the Wulong Formation consists of Quercus semicarpifotia, Q. pannosa, Q. senscens, Q. spathulata, and some species of Thuja, Sabiua, Spiraca, Carpinus, Betula and Rhododendron the flora is mainly composed of evergreen and deciduous broad-leaved trees and along with some conifers, and was thriving under a cooler and arid climate. This flora is quite different from the previous one which caused by the uplift of the Himalayas. The composition of this flora is very similar to the Neogene flora of Yunnan which indicates that at that time Xizang and Yunnan probable belong to the same floristic province. The discovery of Eucalyptus in Xizang shows that the climate of Xizang during Upper Cretaeeous-Paleogene was much warmer than that of Tibet at present. It also shows that this genus which now flourishes in Australia may originate from the northern hemisphere.  相似文献   

16.
The Grünbach flora from the Grünbach Formation of the Grünbach-Neue Welt Basin, Austria, is dated to the Early Campanian on the basis of foraminifers found in this formation and marine fossils serving as stratigraphic markers in the underlying (Maiersdorf Formation) and overlying (Piesting Formation) deposits. The Grünbach flora enumerates 53 species assigned to the Equisetopsida (1 species), Polypodiopsida (11 species), Cycadopsida (1 species), Pinopsida (4 species), Liliopsida (6 species), and Magnoliopsida (30 species). These plants constituted several plant communities, among which the following are more or less reliably defined: aquatic, swamp/semiaquatic, juglandaceous and palm wetland forest, riparian, and mesophytic forest. The Grünbach flora grew in a humid subtropical frost-free climate with a hot summer and a short and relatively dry, but not arid, period during the year.  相似文献   

17.
Dr. Saleh M. Okla 《Facies》1992,27(1):217-223
Summary Late Permian bioclastic calcarenite beds of the middle Khuff Formation were sampled for their algal constituents near the city of Unayzah, Quassim district in central Saudia Arabia. The algal flora includes two species of udoteacean algae (Succodium difficile andSuccodium sp.), the dasycladacean algaMizzia velebitana and two species of red algae (Gymnocodium bellerophontis, Permocalculus plumosus). Other algal floral remains found forming isolated single layers which have generally been named algal microfacies. These include a phylloid microfacies, an oncoid microfacies and algal stromatolites. The Khuff Formation is well-known for its accumulation of non-associated gas and particularly for its oil accumulation in eastern Saudi Arabia and the Arabian Gulf states.  相似文献   

18.
19.
《Geobios》2016,49(3):167-176
In the late 1960s, rests of a low-diversity flora dominated by the lycopsid Pleuromeia were reported. The specimens were recovered from a creek near San Rafael, Mendoza Province, western Argentina, in the lower section of the Puesto Viejo Group, the Quebrada de los Fósiles Formation, considered as Early Triassic in age. Despite the importance of this flora with respect to the end-Permian mass extinction event, it was not yet described nor illustrated. Since then, the age of the Puesto Viejo Group has been revised and the Quebrada de los Fósiles Formation is now considered to be early Middle Triassic. The fossil plants are here first described and interpreted. The most common element, Pleuromeia cf. sternbergii, a species known worldwide that characterizes the post-extinction flora recovery, is accompanied by sphenopsids such as Neocalamites and Equisetostachys, and an herbaceous lycopsid. This community grew up associated with transient water bodies in flood plain environments that developed under warm temperate, strongly seasonal climatic conditions. The landscape was stressed by volcanism, and the conjunction of these factors probably restricted the colonization and development of a full ecosystem, as happened worldwide after the end-Permian mass extinction.  相似文献   

20.
New palm leaves from the Oligocene Ningming Formation are placed into the morphogenus Sabalites because of their costapalmate leaf shape. Four taxa are described on the basis of leaf compressions with cuticular structure. S. guanxiensis sp. nov. is characterised by hypostomatic leaf blades with a stout costa and a symmetrical base. Sabalites cf. asymmetricus has amphistomatic leaf blades with a long, delicate costa and an asymmetrical base. Sabalites sp. 1 has amphistomatic leaf blades with a long, massive costa and wide segments. Sabalites sp. 2 is characterized by hypostomatic leaf blades with a prominent costa and an asymmetrical base. The four new palm taxa expand our understanding of the floristic elements and features of the Oligocene Ningming flora. Together with the other three palm taxa that were previously reported from the Ningming Formation, our material indicates that the Oligocene Ningming flora had a rich diversity of costapalmate palms. The relatively high species diversity of palms and other plants corroborate that the Oligocene Ningming flora represents a warm and humid climate.  相似文献   

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