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1.
西藏新生代秋乌组孢粉化石的发现及其初步研究   总被引:7,自引:0,他引:7  
本文首次报道西藏雅鲁藏布江缝合带附近秋乌组含煤沉积中的孢粉化石。孢粉植物群主要由Quercoidifes,具孔类及三孔沟类花粉组成,包括12科26属及一些未定类群。组合中产有少量的Graminidites及Tsugaepollenites。植物群的总体特征显示其时代可能为渐新世至早中新世。秋乌组沉积早期的环境比较温暖。  相似文献   

2.
记述了南海北部湾盆地涠西南凹陷涠洲油田流沙港组下部储油层所储原油中萃取出的孢子花粉化石28属58种及藻类化石2属3种。通过对比孢子花粉及藻类化石的油源,确定了含油区的油源岩;并根据各类孢型母体植物的古生态特征探讨了油源岩的形成环境。结果表明,中始新统至下渐新统流沙港组暗色泥质岩是北部湾盆地的主力油源岩,中上渐新统涠洲组暗色泥质岩也是该区的油源岩;该区油源岩形成于亚热带温暖潮湿气候下的湖泊沉积环境。  相似文献   

3.
On the basis of palynological data the Paleoeene-Eocene palynoflora from the Tantou Basin in west Itenan are divided into three sporo-pollen assemblages. They are given ill ascending order as follows: 1. The first assemblage (Dazhang Formation) characterized mainly by the predominance of palynoforms of Ulmaeeae anal various Proteaeeous pollen, being assigned to Late Paleoeene and indicating a dry-hot climate. 2. The second assemblage (Lower part of the Tantou Formation) marked by the presence of various Triporopollenites and Tricolporopollenites, belonging to the Early Eocene. A moist-hot climate is reflected. 3. The third assemblage (the Upper part of the Tantou Formation) represented by aboundant pollen grains of saeeated elements (consisting of Pinaeeae and Podocarpaeeae) and the occurrence of Aquilapollenites pollen which plays an important part in this assemblage. It is interpreted as belonging to the middle to early Eocene. The climate was moist and warm. As indicated by the sporo-polleu assemblage the present Paleoeene to Eocene flora in the whole phytoprovienee may belong to a flora transitional from western to eastern China. In this paper the distribution of Aquilapollenites pollen and its stratigraphicai significance are also discussed and it is considered that this kind of pollen distributed in the Paleoeene of China is eertainly not redeposited. At the same time, sonm palynoforms of certain significance for delimitation of Paleoeene and Eocene are provided.  相似文献   

4.
<正> 南宁盆地脊椎动物化石地点目前所知不下七处。本文着重记述了1974和1979年笔者采自邕宁县五塘公社莲塘村的石炭兽化石,并对盆地东部下第三系作一初步划分。本文首次报道南宁盆地发现脊椎动物化石,对研究石炭兽的演化、发展和分布,对盆地第三系地层的划分和对比,提供了新的依据。一、化石地点及地层概况莲塘村位于南宁市东北约32公里、五塘圩东5公里、邕宾(南宁—宾阳)公路南侧。石炭兽化石产于莲塘村东约300米远的小煤窑、距地表8.3米深的褐煤层顶板(灰色泥质粉砂岩)中。  相似文献   

5.
Middle Eocene–early Oligocene ostracode faunal changes in northwestern Kyushu of southwestern Japan are identified in this study. Ostracodes occur from shelf deposits of five formations: the middle Eocene Okinoshima, the upper Eocene Funazu, the uppermost Eocene–lowermost Oligocene Kishima, the lowermost Oligocene Itanoura, and the lower Oligocene Waita Formations. The middle Eocene–earliest Oligocene ostracodes were characterized by warm-water genera, indicating tropical, subtropical and Tethyan genera, whereas the late early Oligocene ostracodes do not include warm-water taxa, consisting of temperate realm genera. The middle Eocene–earliest Oligocene ostracodes do not include remarkable changes of species composition, in contract with equatorial Pacific radiolarians and West Coast USA molluscs. Ostracodes suggest that distinct climatic cooling did not occur in the southwestern Japan during the middle Eocene–earliest Oligocene.  相似文献   

6.
One hundred and eight species of fossil spores and pollen referred to 55 genera found from the Lower Cretaceous Kapushaliang (Kizilsu) Group in the Tarim Basin of Xinjiang have been studied in this paper. The Kapushaliang Group may be divided into the Yageliemu Formation, the Shushanhe Formation and Baxigai Formation in ascending order. The Yageliemu palynoflora is characterized by the predominance of gymnospermous pollen, the relative abundance of pteridophytic spores and the absence of angiospermous pollen. Coniferae is dominant, while Lygodiaceae and Schizaeaceae are important in the flora. The most common species of palynomorphs are Todisporites minor, Cicatricosisporites dorogensis, C. australiensis, Lygodiumsporites subsimplex, Schizaeoisporites cretacius, S. zizyphinus, S. certus. Cibotiumspora paradoxa, Cyathidites australis, C. minor, Biretisporites potoniael, Cycadopites minimus, Pseudowalchia hiangulina, Parvisaccites radiatus, Podocarpidites multesimus, P. canadensis, Alisporites bilateralis, Cedripites cretaceus, C. canadenris, Abietineaepollenites microalatus, Clarsopollis classoides, C annulatus, C. xinjiangensis (sp. nov.), Ephedripites multicostatus, E. tarimensis (sp. nov.), etc . The palynoflora is comparable with those of the lower part of the Lower Xinminbu Formation in northwestern China and the lower part of the Lower Mannville Formation in western Canada, which is considered corresponding from Berriasian to Valanginian in age. The Shushanhe palynoflora is also characterized by dominance of gymnosperms and subdominance of pteridophyta. Some primitive angiospermons pollen grains are found in the upper part of the formation. In addition to the most common species of the above mentioned palynoflora, the important species in the present palynoflora comprise Cicatricosisporites potomacensis, C. orbiculatus, C. subrotundus, Concavissimisporites punctatus, C. verrucosus, C. globosus, lmpardecispora apiverrucata, Trilobosporites crassus, T. trioreticulosus, Pilosisporites verus, P. trichopapillosus, Klukisporites pseudoreticulatus, Verrucosisporites obscurilaesuratur, Converrucosisporites saskatchewanensis, Foraminisporis wonthaggiensis, Cingulatisporites valdensis, C. ruginosus, Jiaohepollis verus, Pityosporites constrictus, etc. More than 40 in dicative species of Early Cretaceous occur in the assemblage. The palynoflora compares clcsely with those of the middle part of the Lower Xinminbu Formation and the Quartz Sand Member of the Lower Mannville Formatton. It is suggested that the Shushanhe Formation should belong to Hauterivian of Barremian in age. The Baxigai palynoflora is basically similar to the Shushanhe palynoflora. But the palynoflora shows an obvious increase in abundance of lygodiaceous spores and angiospermous pollen accompanied by a great reduction of Classopollis and Ephedripltes. Most of the Early Cretaceous species occurring in the above mentioned palynofloras are present. In addition, some Cretaceous species recorded from Aptian and Albian Stages in Europe, North America and Australia, such as Trilobosporites tribotrys, T. trioreticulosus, Coptospora paradoxa, Camarozonosporites insignis, Crybelosporites punctatus, etc., appear in the assemblage. In comparison with the microfloras of the upper part of the Lower Xinminbu Formation, the Upper Mannville Formation and the lower part of the Lower Colorado Group, the Baxigai Forma- tion should be referred to Aptian to Albian in age. Judging from the palynofloras, the early Cretaceous palaeoclimate in the basin should belong to the arid or semi-arid type of the subtropic zone. However, from Barremtan through Albian the climatic conditions might appear relatively wet.  相似文献   

7.
滇西保山地区丁家寨组生物群的时代   总被引:2,自引:0,他引:2  
首次系统描述保山地区丁家寨组的类化石,详细讨论丁家寨组所产类和腕足类动物群及孢粉植物群的时代和性质,提出丁家寨组的时代应与华南早二叠世的紫松阶相当,即相当于国际上的Asselian阶至Sakmarian阶。确认丁家寨组不存在不同时代化石的再沉积混杂或大量化石时代倒置的异常现象。丁家寨组出现特提斯型Eoparafusulina动物类;腕足类组合属介于西澳区和泰马区之间的过渡动物群,西澳区的色彩较浓;  相似文献   

8.
DISCOVERY OF TWO MID-TERTIARY MAMMALIAN FAUNAS FROM HAIYUAN, NINGXIA, CHINA   总被引:2,自引:1,他引:1  
Inl988-199otheRegionalGeologicalSurveyTeamoftheGeologicalBureauofNingxia(RGSN)foundsomefossilmammalsinthelowerpartoftheHo11g1iugouFormationandtheupperpartoftheOligocene.Inl992ajointteamoflnstituteofVertebratePaleontologyandPaleoanthropo1ogy,AcademiaSinica(IVPP),andtheRGSNwenttoHaiyuailCountyandcollectedmorefossilmamma1sfromtheYuanjia-wowoareausi11gascreen-washingmethodThemammalfaunafromthelowerpartoftheHongliugouFormationiscomposedofAprotodonsp.,Indricotheriidaeindet.,Rhinoceroti…  相似文献   

9.
朝鲜安州盆地早白垩世孢粉组合   总被引:7,自引:0,他引:7  
报道朝鲜安州盆地下白垩统龙盘组孢子花粉34 属59 种(包括2 新种),并根据孢粉组合讨论了地质时代和古气候特征。龙盘组孢粉组合以裸子植物花粉为主,蕨类植物孢子次之,出现少许原始被子植物花粉。松柏纲花粉在组合中占绝对优势;海金沙科和莎草蕨科孢子则在蕨类中占优势。根据孢粉组合,龙盘组的时代应属早白垩世巴列姆期至阿普第期;安州盆地当时气候温暖偏干,属亚热带半干旱型  相似文献   

10.
报道一个产于上泽亚(Uupper Zeya)坳陷(东经129-130°,北纬54-55°)东南部,保存良好的化石孢粉植物群.孢粉组合中裸子植物花粉居统治地位,占总数的53.4%,其中Taxodiaceae占36.3%,松科仅占5%.被子植物花粉占39.9%,多为葇荑花序类,如胡桃科、桦木科、山毛榉科等;同时还有不少反映温暖气候的分子,如Liquidambar,Balsaminaceae,Magnoliaceae,Nyssaceae等.孢子植物占21%.这样的孢粉植物群代表了潮湿温暖的温带气候.孢粉学至今在坳陷区内仍是人们用以确定地层时代的唯一依据.Pistillipollenites macgregorii,Anacolosiditessuplingensis,Ulmoideipites tricostatus及U. crempii等的出现可以确定含孢粉地层的地质时代属于中-晚始新世.斯涅日诺戈斯克产煤区中晚始新世沉积中的孢粉层位与普里阿姆尔耶,雅库提亚和亚洲东北部的同期沉积相当.  相似文献   

11.
艾森贝格盆地(Eisenberg Basin)位于梅因茨盆地(Mainz Basin)西南部,为莱茵地堑的一部分,因为化石稀少,这里的地层和梅因茨盆地典型的第三纪地层很难对比,因此,它们的地质时代长期处于争论中。对于Lautersheim 1钻孔及Lautersheim附近地层露头的孢粉地层学研究表明,这一地区的第三纪可以三分,Lautersheim 1钻孔的下部属于中始新统,相当于Krutzsch的SPP 15/16带,该钻吉中部的一部分可置入早渐新世,相当于SPP19带;这部分可以再分为上下两部分;下部含大量始新世微体植物化石,而上部此类化石很少,上部属于下渐新统,与含孢粉的Sandpit “Friedlich”可以对比。Lautersheim 1钻孔最上部属于晚渐新世(早Chattian),与“过滤层”顶部及“淡水层”底部可以对比,其所含的孢粉和Marxheim组合可以比较,相当于SPP 20F/G带。  相似文献   

12.
《Palaeoworld》2022,31(1):131-139
The Dawenkou Basin is a Cenozoic terrestrial fault basin in Shandong Province, East China, containing abundant mineral resources, especially gypsum. Recently a borehole was drilled in this basin unearthing the upper and middle members of the Dawenkou Formation. From the upper member, well-preserved ostracodes were discovered, which are entirely non-marine taxa including species of Eucypris, Caspiolla, Candona and Candoniella. Based on the new material, a new species Candona dawenkouensis n. sp. was erected. The ostracode assemblage biostratigraphically indicates an age of middle Eocene to Oligocene of the upper member of the Dawenkou Formation and the strata bearing mineral resources (mainly gypsum) of the middle member of the Dawenkou Formation is likely early Eocene.  相似文献   

13.
Palaeogene deposits are widespread in China and are potential sequences for locating stage boundaries. Most strata are non‐marine origin, but marine sediments are well exposed in Tibet, the Tarim Basin of Xinjiang, and the continental margin of East China Sea. Among them, the Tibetan Tethys can be recognized as a dominant marine area, including the Indian‐margin strata of the northern Tethys Himalaya and Asian‐margin strata of the Gangdese forearc basin. Continuous sequences are preserved in the Gamba–Tingri Basin of the north margin of the Indian Plate, where the Palaeogene sequence is divided into the Jidula, Zongpu, Zhepure and Zongpubei formations. Here, the marine sequence ranges from Danian to middle Priabonian (66–35 ma), and the stage boundaries are identified mostly by larger foraminiferal assemblages. The Paleocene/Eocene boundary is found between the Zongpu and Zhepure formations. The uppermost marine beds are from the top of the Zongpubei Formation (~35 ma), marking the end of Indian and Asian collision. In addition, the marine beds crop out along both sides of the Yarlong Zangbo Suture, where they show a deeper marine facies, yielding rich radiolarian fossils of Paleocene and Eocene. The Tarim Basin of Xinjiang is another important area of marine deposition. Here, marine Palaeogene strata are well exposed in the Southwest Tarim Depression and Kuqa Depression. They comprise mostly neritic and coastal lagoon facies of the Tethyan realm. Palaeontological evidence suggests that the Paleocene/Eocene boundary here is in middle of the Qimugen Formation. The Tarim Basin was largely drained by Late Oligocene. To the east, the marine offshore Palaeogene strata are widespread in the North Taiwan and East Zhejiang depressions of the continental shelf basin of East China Sea. Abundant fossils including foraminifera, calcareous nannofossils, ostracods, pollen and bivalves occur in the marine environment. Biostratigraphically, the sequence is well correlated with the international planktonic foraminiferal and nannofossil zonations.  相似文献   

14.
兰州盆地早第三纪植物及古气候意义   总被引:10,自引:0,他引:10  
化石采自甘肃省兰州盆地咸水河组底部,经研究认为有29种,归属20属12科。它们是:樟科 Lauraceae (Daphnogene),木通科Lardizabalaceae(Akebia),小檗科Berberidaceae(Berberis),榆科Ulmaceae (Planera,Ulmus,Zelkova),桦木科Betulaceae(Alnus,Carpinus),杨梅科Myricaceae(Myrica),杨柳科Sali- caceae(Populus,Salix),紫金牛科Myrsinacese(Ardisia),蔷薇科Rosaceae (Prunus,Sorbus,Sorbaria,Spir- aea),豆科Leguminosae(Gleditsia,Sophora),漆树科 Anacardiaceae(Rhus),忍冬科Caprifoliaceae(Viburnum) 等。经植物区系组成与叶相分析显示,该植物区系的大多数成员是落叶阔叶乔、灌木,少数为常绿灌木。其中特殊的分子是 Rhus turcomanica Korov.ex Vassilvesk,该成分是早第三纪中、晚期的标志化石植物。另一化石植物 Sorbaria callicomifolia Kornilova曾出现在中亚的早渐新世,最晚至早中新世。同一层位采集的孢粉样分析结果显示:该组合仅约20种,种类相对贫乏,并以被子植物的花粉占优势。其中出现裸子植物的麻黄粉,被子植物的白刺粉及蒿粉等,这几个类型均指示沉积时期经历干旱气候。综合植物大化石及孢粉分析研究,均出现一些指示气候为亚热带干旱或周期性干旱气候的特点,并据Rhus turcomanica出现的最晚记录,推测咸水河组底部的地质时代大约是早渐新世晚期。  相似文献   

15.
A palynostratigraphic and palynofacies study of a geological section at Cuojiangding in Zhongba County has provided a basis for discussing the palaeoenvironmental evolution of the southern continental margin of Laurasia in Xizang (Tibet) towards the end of the Cretaceous Period and during the Paleogene. It is the only record of fossil spores and pollen grains from collision- and convergence-related sediments close to the major Yarlung Zangbo Suture. Deposits of the Padana Formation at the base of the section through the Qubeiya, Quxia, and Jialazi formations to the Rujiao Zangbo Conglomerate at the top are considered to range in age from Santonian to Eocene or possibly Oligocene. During this period the India plate collided with, and continued to push against, Laurasia plate. Two spore and pollen zones and three palynofacies types are recognized. These are correlated with two transgressive–regressive cycles associated with the collision, periods of geologically rapid uplift being reflected by the molasse-like sediments of the upper Quxia Formation and the Rujiao Zangbo Conglomerate, which accumulated during the Late Paleocene and Eocene–Oligocene respectively. The first regression led to intermittent subaerial exposure and erosion of the Cuojiangding area. The second ended the marine history of the area and led first to the development of swamps in a subtropical climate, now preserved in the coal-bearing Qiuwu Formation, and later to the development of mountainous terrain, with a cooler climate at higher elevations.  相似文献   

16.
20世纪70至80年代,几乎所有关于江汉盆地跑马岗组和渔洋组的古生物文献都将其时代确定为晚白垩世。李伟同在深入地研究了跑马岗组标准剖面上的轮藻化石后提出跑马岗组大部分属于古新统。取自层位与跑马岗组相当的渔洋组上段上部的岩芯样品经分析后获得了丰富的孢粉化石。这一组合总的面貌与王大宁等获得的晚白垩世渔洋组的第三组合区别明显,而与古近纪的新沟嘴组的第四组合相似处很多。在该孢粉植物群中,常见于当地的晚白垩世分子,如希指蕨孢属、克拉梭粉属、江汉粉属、刺参粉属、鹰粉属等没有或极少见到。而在本组合常见的南岭粉属、五边粉属、漆树粉属等多出现在我国南方古新世地层中。因此,其时代很有可能为古新世。如果是这样,渔洋组上部有可能跨越了白垩系和古近系界线。从当前孢粉植物群含有很多亚热带成分以及麻黄粉属以及胡颓子粉属、忍冬粉属等看,它反映了江汉盆地当时偏干旱的亚热带气候。  相似文献   

17.
The palaeoenvironmental reconstruction of central Tibet is key to understanding the uplift history of the Tibetan Plateau, which had a profound influence on Cenozoic global climate and biotic change. Here we report an amber layer from the lower part of the Dingqing Formation (late Oligocene) in Lunpola of central Tibet, which is the first record of amber from Tibet. Herein we find that Lunpola amber is derived from dipterocarp trees, as determined by gas chromatography-mass spectrometry, which are restricted to and dominant in Asian rainforest nowadays. This amber forest represents the northernmost dipterocarp forest and is consistent with the hypothesis of out-of-India dispersal of Asian dipterocarps. The Lunpola amber most probably was derived from the lower part of the Niubao Formation (early–middle Eocene) and suggests a tropical/subtropical wet forest was present in central Tibet at least before the late Oligocene (probably early–middle Eocene).  相似文献   

18.
In the northern part of South China Sea, including Tonkin Gulf, Hainan Island, Leizhou Peninsula and some basins of Guangdong Province, Oligocene deposits are composed of motley, mainly grey, greyish green and dark red clay and sandstone, containing very rich pollen and spores. Most of them are of the components which exsisted in Tertiary, particularly in Oligocene deposits of Northern America and Eurasia, such as Gothanipollis paichanensis Ke & Shi, Ulmus granopollenites Rouse, Symplocos scabropollinia Traverse, Engelhardtia spackmaniana Traverse, etc. At the same time some important Oligocene and Early Miocene pollen types of Borneo are found there, such as Crassoretitriletes vanraadshooveni Germeraad & al., Florschuetzia semilobata Germeraad & al., F. trilobata Germeraad & al., Magnastriatites howardi Germeraad & al., Jandufouria seamrogiformis Germeraad & al., Verrucatosporites usmansis (Hammen) Germeraad & al., Margocolporites vanwijhci Germeraad & al., Psilatricolporites operculatus Hammen & Wymstra, Monoporites annulatus Hammen and Zonocostites sp., etc. On the other hand in Oligocene palynoflora of Borneo there appear pollen types assigned to temperate plants or mountain plants of northern hemispherae (Pinus, Picea, Tsuga, Ephedra and Alnus), which are found in abundence in Oligocene palynoflara of the investigated area particularly in Late Oligocene. All of this indicats that the palynoflora of the Northern part of South China Sea was closely related with that of Borneo in Oligocene. This similarity of palynofloras in the two localities may be due to the geographycal proximity of Borneo to the main land of Asia. In paleoecological aspect, we have found there is plenty of pollen and spores of land and fresh water plants, while those reflecting marine and coastal enviroments (Rhizophora and Sonneratia) are rather scanty. This shows that in Oligocene period the investigated area was a land. Tonkin Gulf along with Hainan Island and Leizhou Peninsula formed an inland depression at that time. Abundant pollen of mountain plants and temperate plants indicats, that there weremountains in or around the area of interest.  相似文献   

19.
内蒙千里山地区中、上渐新统的发现及其意义   总被引:9,自引:7,他引:2  
在这篇文章中,根据所发现的脊椎动物化石和岩性,将内蒙伊克昭盟千里山地区陆相第三纪地层分为四部分。并建立了两个组:上部上渐新统伊克布拉格组和中部中渐新统乌兰布拉格组。后者被分为上、下两段。在亚洲,一直未能发现完整的,具有丰富脊椎动物化石的中、晚渐新世地层的剖面。千里山地区渐新统连续剖面的发现,对亚洲中、晚渐新世地层的层序的建立和对比提供了可靠的依据。  相似文献   

20.
The ring‐cupped oaks (Quercus subg. Cyclobalanopsis) characterized by united and concentric ring‐cupped acorns, are mainly distributed in broad‐leaved evergreen forests in tropical and subtropical regions of East and Southeast Asia. Their geological history has been traced from the middle Eocene to Pleistocene. Most reports of the subgenus have been on the basis of leaves, whereas the acorns or cupules, more valuable evidence for the inter‐ and intrageneric classifications, have been relatively poorly documented. Here, we describe a new species, Quercus shangcunensis sp. nov., based on a ring‐cupped fossil acorn and pollen on the acorn, as well as Quercus sp. associated leaves, recovered from the early Oligocene Shangcun Formation of Maoming Basin, Guangdong Province, South China. The morphological and anatomical structures of these fossils confirm their attribution to the subg. Cyclobalanopsis. Quercus shangcunensis sp. nov. represents the world's first Oligocene fossil acorn and the earliest fossil acorn in China for the subgenus, indicating that the subg. Cyclobalanopsis arrived in the low latitude area of South China at least by the early Oligocene. Our fossil provides evidence that the subgenus was present in one of its modern distribution centers in the Oligocene, suggesting that the modern distribution patterns of the subg. Cyclobalanopsis most likely originated during or prior to the Oligocene.  相似文献   

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