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1.
In the northern part of South China Sea, including Tonkin Gulf, Hainan lsland, Leizhon Peninsula and some basin of Guangdong Province, Paleogene deposits are composed of three formations: the Weizhon, the Liushagang and the Changliu formations arranged in descending order. The paper on the palynoflora of the Weizhon Formation (early and middle Oligocene) is in press[2]. This paper deals only with the palynoflora of the Liushagang Formation, with may be divided into four main stages: The first stage is represented by Monocolpollenites tranquillus and Crassoretitriletes sp., assigned to early Eocene The second stage is characterized by Salixipollenites, Momipites triletipollenites and Operculumpollis. Its age is middle Eocene. The third stage is dominated by some species of Quercoidites and Ulmipollenites and also characterized by the presence of Platycaryapollenites and Prominangularia dogyingensis, This sporo-pollen assemblage suggests a late Eocene in age. The fouth stage is marked by profusion of some alga of brockish water, such as Rugasphera corrugia, Granodiscus gronulatus and some pollen types of Liquidambarpollenites minutus, Multiporopollenites puctatus and Tricolporopollenites minutus. The age of the last stage is assigned to early oliocene. In generaly, the palynoflora of the Liushagang Formation is quite different from that of the Weizhou Formation. The main types of spores and pollen are common with those found in Europe and North America of the same age, while the Weizhou Formation has many elements common both in this region and Borneo. During Eocene and early Oligocene this area was of continental phase with brackish basins. At the beginning the climate was rather moist and hot, but then itbecame moist and warmtemperate.  相似文献   

2.
As late cretaceous and Paleocene was an important stage in the evolution of angiosperms, so studies on flora of this periiod are of great significance. In recent years many palynological data of late Cretaceous and Paleocene have been recorded from different parts of China, especially the Southeastern China. An attempt is made here to allow deductions regarding the problem of existence of some palynological provinces during this period in China. Three provinces may be divided as follows. I. The wet subtropical and warm-temperate palynofioristical province of northeastern China. During late Cretaceous, this palynoflora was marked by occurrence of Aquilapollenites, Mancieorpus, Fibrapollis and Wodehouseia. Aquilapollenites amplus, A. crassus, A. megaprojeetus, A. asper, A. affenatus A. alatus, Mancieorpus andaensis, FiburapaUis mirifieus and Wodehouseia oeulata ...... are noted. Besides these eharacteriestic elements, there are many species of Proteaeiites and some species of Beaupreaidites, Loranthacites, Quereoidites, Salixipollenites, Gothanipollis, Plicapollis, Utmoideipites, Cranwellia, Alnipollenites and Trieolporopollenites. Gymnosperms pollen comprise Abietineaepollenites, Pinuspollenites, Cedripites, Taxodiaceaepollenites and Araueariacites. Sehizaeoisporites are very rich in species and numbers. Polypodiaceoisporites, Osmundacidites and Cyathidites are rarely Maud. Paleocene palynoflora is characterized by scantiness or absence of Aquilapollenites and Wodehouseia. Paraalnipollenites eonfusus, P. orthoeostatus, BetulaepoUenites pli eoides and some species of Myricipites, Comptonia and Momipites are predominant. These pollen may be related to Betulaceae, Juglandaceae and Myricaseae. Taxodiaceaepollenites, Cedripites and Podoearpidites are commen, It reflects that during late Cretaceous the flora was wet and subtropical, but in Paleocene, it turned to be wet and warm-temperate. According to the abundanee of Aquilapollenites and Wodehouseia, this palynoflora may belong to the Eastern AsianWestern North American Paly-nofioristical Province. II. Arid subtropical palynofioristieal province of South China. During late-Cretaceous this palynofiora comprises Morinopollenites Wang & Zhao (M. normalis, M. minor, M. polyprojeetus, M. rhombiformis) and Janhangpollis Wang & Zhao (J. radiatus, J. arciformis, J. sayaxngensis, J. ringes, J. mikros). Besides this, species of Proteacidites, Beaupreaidites, Myoporumpollenites, Crassimarginpollenites, Cranwellia, Magnolipollis, Rutaceoipollenites, Ilexpollenites, Symplocospollenites, Nyssapollenites, Palmaepollenites and Chenopodipollis were recorded. Classopollis, Exessipollenites and Rugubivesieulites were abundant in this assemblage. Aquilapollenites is rarely recorded, except along the coast region of eastern China. In paleocene some species of Nanlingpollis Sun & He, Pentapollenites jiangsiensis, Tricolporopollenites rombicus and Sapotaceoidaepollenitess trieoloporatus are recorded, but Morinopollenites and Janhanpollis were unknown. Ulmoideipites, Ulmipollenites, Ephedripites and some verrucate spores (Pterisispora) were very abundant. According to the feature of the pouch assemblages, the flora of South China during that time was of arid subtropical in nature. It seems to be nothing to do with other palynofloristical provinces in the world. III. Arid subtropical palynofloristical province of Northwestern China. Palynofiora of this period has been recorded from a few localities throughout this area. Normapolles group (Atlantopollis, Pseudoatlantopollis, Chaonopollenites, BasopoUis and ExtratriporopoUenites), Proteacigites microverrucatus, Eehitriporites magnus and Triatriapollenites echinatus were present. Besides that, Beaupreaidites, Rutaceoipollenites, Lonicerapollis and Engelhardtioipollenits were also occurred. In gymnosperms Ephedripites and some disaccate pollen were abundant. The percentage of Normapolles is increasing from east to west, while Proteaeidites is decreasing. In Paleocene Nudopollis and Trudopollis of Normapolles group were present, while Proteacidites 8issappeared. The palynoflora of this province was of an arid and subtropical in nature, which is somewhat in connection with the European-Eastern American Palynofloristical Province by the presence of Normapolles.  相似文献   

3.
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   

4.
从孢粉学论证东海盆地下第三系的存在   总被引:1,自引:0,他引:1  
传统的地质学观点,将东海盆地与台湾海相地层相提并论,以至误解东海盆地只有上第三系沉积。而在东海海域龙井构造中首钻的龙井一井和次钻的东海一井下部地层中所获得的孢粉组合证明,东海盆地龙井构造史前的早第三纪时曾与苏北相连成陆,只是在晚渐新世一早中新世时才全面解体接受海侵,这一事实表明,其成盆历史大体与南海相仿。  相似文献   

5.
Fossil plants from the lower part of Xianshuihe Formation in the Lanzhou Basin, Gansu Province were studied. The flora contains 29 species, representing 20 genera and 12 families, which include Lauraceae ( Daphnogene ), Lardizabalaceae ( Akebia ), Berberidaceae ( Berberis ), Ulmaceae ( Planera, Ulmus, Zelkova ), Betulaceae ( Alnus, Carpinus ), Myricaceae( Myrica ), Salicaceae ( Populus, Salix), Myrsinaceae(Ardisia), Rosaceae ( Prunus, Sorbus, Sorbaria, Spiraea ), Leguminosae ( Gleditsia, Sophora), Anacardiaceae (Rhus), Caprifoliaceae(Viburnum). An analysis of the floristic elements and their foliar physiognomy shows that most members of the flora are deciduous broad-leaved trees or shrubs with a few evergreen shrubs. The most noteworthy species is Rhus turcomanica which was present in the Middle Eocene to Late Eocene of Central Asia (Kazakhstan, Turkmenistan). Generally, Rhus turcomanica occurred at the same beds as Palibinia, an extinct fossil plant whose presence indicates a subtropical dry climate. Another species, Sorbaria callicomifolia Kornilova was present from the Early Oligocene to Early Miocene of Central Asia (Kazakhstan and Turkmenistan). According to an analysis of spores and pollen, this flora contains over 20 species. It is predominated by the angiosperm pollen. There appeared Ephedripites and Nitrariadites which were important elements in the dry area. Ephedripites was found from the Upper Cretaceous to Early Tertiary. Nitrariadites occurred in the Late Miocene, whereas Rhus turcomanica and Sorbaria callicomifolia were both reported in the subtropical dry area from the Middle Eocene to Early Oligocene. The latest record of Rhus turcomanica is from the Middle Eocene to Early Oligocene of Central Asia. The presence of this element in the lower part of Xianshuihe Formation may indicate that itsage is the latest stage of the Early Oligocene.  相似文献   

6.
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   

7.
河南潭头、卢氏和灵宝盆地上白垩统一下第三系的划分   总被引:4,自引:3,他引:4  
在这篇短文中,根据脊椎动物化石的发现,进一步叙述和讨论了豫西潭头、灵宝和卢氏三个盆地的中、新生代地层的划分问题。在这三个盆地的中、新生代堆积物中,属于晚白垩世的有潭头盆地秋扒组和灵宝盆地的南朝组,后一个盆地还可能存在着时代更早的白垩纪地层。在潭头盆地的高峪沟组和大章组中分别找到中古新世的阶齿兽、中兽科和晚古新世的牧兽科、假古猬科化石;在潭头组中发现原恐角兽类和古脊齿兽类化石,时代为早始新世。在灵宝盆地的项城群中尚未找到哺乳类化石,可能包括古新世和始新世早中期的堆积。卢氏盆地的卢氏组和锄钩峪组以及灵宝盆地的川口组和浑水河组的时代为晚始新世。卢氏组下部和川口组或许可延至中始新世。  相似文献   

8.
黑龙江省东部柳树河盆地古近系八虎力组为一套含油页岩矿床的地层。目前,对其时代的认定还没有确切的古生物学依据,尚存在不同的看法,同时,关于成矿环境的探讨也较薄弱。通过对该套地层开展系统的孢粉学研究,由下向上划分了4个孢粉组合,分别是Quercoidites-Retitricolpites-Retitricolporites组合、Retitricolpites-Retitricolporites组合、Polypodiaceaesporites-Retitricolpites-Retitricolporites组合和Pinuspollenites-Polypodiaceaesporites组合。根据孢粉组合特征,详细讨论了孢粉组合的地质时代,指出八虎力组时代为中始新世至晚始新世。根据孢粉组合的组成情况推测,八虎力组沉积时为亚热带-暖温带温暖湿润气候下的山间盆地环境。在山地高处生长有针、阔叶混交林植被,在低洼处生长有湿地水生植物、蕨类和苔藓类,从而有利于油页岩的形成和保存。温度向上可能有所降低,但幅度并不大。  相似文献   

9.
The Cintura Formation of Albian–Cenomanian age in the Cabullona Basin yielded an important fossil flora, including palynomorphs, leaf impressions and fossil trunks. At the base of the Marquechi Member a poorly preserved palynomorph assemblage is recognised. The palynological assemblage is dominated by gymnosperms, mainly by cheirolepidiacean genus Classopollis. A noteworthy feature is the presence of angiosperm pollen grains of the genera Clavatipollenites, Retimonocolpites and Tucanopollis. A rich, diverse and well-preserved macroflora of leaf impressions has been observed in the uppermost part of this formation belonging to the San Juan Member. There are at least eight morphospecies of leaves including an abundance of taxa with possible botanical affinities to the family Sapindaceae. The angiosperm pollen grains together with the sapindalean leaves constitute the oldest record of such remains in Mexico.  相似文献   

10.
甲查拉组位于藏南特提斯喜马拉雅北带的江孜盆地,是江孜地区的最高海相地层,被视为新特提斯洋关闭时代的主要证据。通过对甲查拉组剖面的孢粉分析,自下而上划分为3个孢粉组合带:1 Ulmipollenites minor+Ulmoideipites-Myricipites组合带;2 Quercoidites-Caryapollenites组合带;3 Abiespollenites-Betulaceoipollenites+Betulaepollenites组合带。甲查拉组孢粉植物群揭示出其沉积自晚古新世开始,其沉积结束可能延续到早渐新世。推测晚古新世—早始新世为温暖湿润的暖温带或亚热带气候,始新世中晚期为温暖、潮湿的亚热带气候,早渐新世为温和湿润的暖温带气候。  相似文献   

11.
拉萨地区林周盆地典中那玛剖面设兴组上部新发现的孢粉组合以落叶、阔叶植物为主体,主要为桦科的Alnipollenites,Betulaepollenites,Carpiniptes,山毛榉科的Quercoidites,胡桃科的Juglanspollenites,榆科的Ulmipollenites,椴科的Tiliapollenites等,孢粉化石多为古近纪常见分子,未发现白垩纪的特征分子。古近纪早期大量出现的三孔沟,网面三孔沟等花粉少量出现;孢粉组合更接近于古近纪中晚期的面貌,其时代可能属于晚始新世。因此,设兴组上部的年代可能是始新世晚期。由此推论,设兴组和林子宗群之间的角度不整合不能代表白垩纪古近纪之间的构造运动,而是代表始新世晚期后的构造运动。同时,林周盆地可能沉积有古近纪的河湖相地层。  相似文献   

12.
湖北秭归盆地中侏罗世陈家湾组孢粉组合的发现及其意义   总被引:1,自引:0,他引:1  
本文首次报道了湖北秭归盆地陈家湾组孢粉组合,该组合可归入Cyathidites minor-Classopollis Callialasporites为代表的组合,时代属中侏罗世。陈家湾组孢粉组合的特征反映了秭归盆地中侏罗世泄滩组、陈家湾组和沙溪庙组三个组的孢粉组合的面貌基本一致,仅早期组合与中、晚期组合略有差别。建议以Gyathidites minor-classopollis-callialasportes组合代表湖北西部——重庆地区中侏罗世孢粉组合,早期为Lunzisporites pallidus亚组合,中晚期为Converrrcosisporites venitus亚组合。根据孢粉植物群在本区侏罗纪垂直分布情况,提出早侏罗世时期属亚热带一热带炎热潮湿气候环境,植物生长茂盛;早侏罗世之后,潮湿的气候仍占主导地位,但出现了干旱的先兆;中侏罗世早期进入了半干旱阶段,随后即为炎热干旱的气候所笼罩;至晚侏罗世达到非常干旱的程度,植物种类十份单调,唯有掌鳞杉科植物占据着统治地位。  相似文献   

13.
An assemblage of 46 fossil pollen and spore types is described from a core drilled through the middle Eocene Saramaguacán Formation, Camagüey Province, eastern Cuba. Many of the specimens represent unidentified or extinct taxa but several can be identified to family (Palmae, Bombacaceae, Gramineae, Moraceae, Myrtaceae) and some to genus (Pteris, Crudia, Lymingtonia?). The paleoclimate was warm-temperate to subtropical which is consistent with other floras in the region of comparable age and with the global paleotemperature curve. Older plate tectonic models show a variety of locations for proto-Cuba during Late Cretaceous and later times, including along the norther coast of South America. More recent models depict western and central Cuba as two separate parts until the Eocene, and eastern Cuba (joined to northern Hispaniola) docking to central Cuba also in the Eocene. All fragments are part of the North American Plate and none were directly connected with northern South America in late Mesozoic or Cenozoic time. The Saramaguacán flora supports this model because the assemblage is distinctly North American in affinities, with only one type (Retimonocolpites type 1) found elsewhere only in South America.  相似文献   

14.
云南元谋盆地湾堡甘棠组植物群的叶化石和孢粉化石合计107种类型,分属86属,47科。植物叶化石包括18科,24属,35种。除一种裸子植物外,其它均为被子植物。被子植物中,榆科、桦木科、豆科无论属种或者化石数量都是最多;杨柳科、槭科、蔷薇科次之;壳斗科、樟科、杨梅科、鼠李科、忍冬科、胡颓子科、杜鹃科、香蒲料、禾本科均有代表。甘棠组的孢粉植物群也相当丰富,合计97个类型,分属72属,44科。以松科、榆科、禾本科及蕨类植物的水龙骨科最为丰富,胡桃科、壳斗科、金缕梅科及蕨类植物的凤尾蕨属也很常见。被子植物花粉占孢粉总数的50%--60%,以禾本科和榆属花粉含量最高,多在10%以上。裸子植物绝大部分为松科花粉,占孢粉总数的20%-30%。孢子以水龙骨科和凤尾蕨属为主,二者各占孢粉总数的5%-10%。发现于元谋盆地湾堡甘棠组的植物叶化石以及孢子花粉组合在成分上都是混合的类群。组合中既有相当多的湿润亚热带常绿阔叶林成分,也有耐干旱的胡颓子、杨梅、旱蕨等灌木、小乔木或草本分子,同时还有含量很高的、在半干旱环境下也能生存的禾本科、榆科花粉。据此推测甘棠组的植物群和孢粉组合反映了上新世时元谋地区的植被已经分化,盆地的周围山地生长有松科、壳斗科、樟科、胡桃科、金缕梅科为主的常绿和落叶阔叶树木或林块,可能有少许杜鹃科小乔木混杂其中,属于地带性植被。而在盆地内则是以禾本科、蔷薇科等为主,杂以大戟科、豆科、忍冬科、杨梅科等灌木或草本植物以及榆科、桦木科等树木组成的稀树灌丛草原型植被。盆地内的植被所反映的气候和周边地区相比,显得明显干旱。因此推测元谋盆地在2-3百万年前的中晚上新世已经发育成为金沙江流域的干热河谷盆地之一。  相似文献   

15.
黑龙江嘉荫县渔亮子组是我国最早发现爬行动物化石的层位,盛产鸭嘴龙等爬行类化石,前人认为,该组在层位上相当于北美晚白垩世马斯特里赫特期Edmonton群,HellCreek和Lance组,但孢粉化石资料提示,渔亮子组中的被子植物花粉尚未发展至上述群(组)的阶段,其层位应较之低,大致相当于北美的坎佩尼期BellyRiver群(组)或相当层位。  相似文献   

16.
The pollen analytical investigation of 226.07 m,, deep QH70 core from Fulaerji district in the city of Qiqihar, Heilongjiang province have been carried out. Based on the characteristics of QH70 core sporo-pollen assemblages, seven pollen zones may be subdivided in the order as follows: The first zone (Ⅰ) belongs to early period of the Late Cretaceous. When the flora was mainly composed of gymnosperm, the next was fern and a little original angisperm. Here the climate was hot and wet and the vegetation showed tropical-subtropical in aspects. In this core the author didn't find the Palaeogene flora. The Ⅱ–Ⅲ zones belonging to the Late Tertiary are characterized by predominance of arboreal pollens, mainly consisting of Amentiferae and some conifers. The flora of the Neogene was mainly composed of Pinus, Betula, Castanea, Ulmus, Corylus, Alnus, ,Juglans, Quercus, Carya, Fagus, Tsuga etc. some subtropical species of Hamamelis, Liquidambar, Castanopsis, Melia. Myrica and Taxodiaceae which still existed. The climate was warm and humid with the annual temperature higher than that of the present. As to the last period of the third zone (Ⅲ) the assemblage of herbaceous plants and semi-shrub were predominant. The climate was changed into cool and less dry. The fouth pollen zone (Ⅳ) is represented by herbaceous plants such as Artemisia, Chenopodiaceae, Gramineae, Polygonaceae etc. indicating the Fulaerji was covered by cold-temperature grassland with a cold and dry climate. According:to temperature decreasing at this zone, magnetostratigraphy and thermoluminescence dating we may take the start of the Ⅳ zone as the mark of the beginning of Quaternary in this region. The age of the boundary between Pliocene and Pleistocene might be 2.4 million years or so. The geological age of pollen zones Ⅳ–Ⅶ, is assigned to Pleistocene. The characteritics of the sporo-pollen assemblage at these zones are quite different from one another. In the fifth pollen zone (Ⅴ), the vegetation was represented by a steppe or tundra with a cold and dry climate at its initial stage, but in the late stage the flora was characterized by a deciduous broadleaved forest and steppe, indicating the climate was warm and less humid. Pollen zones Ⅵ–Ⅶ, the herbaceous plants, such as Artemisia, Gramineae, Chenopodiaceae etc. were predominant. The climate was rather dry and cold. The plants of the boreal conifers as Picea, ilbices, Larix, Pinus and the subpolor plants such as Betula were thriving in the low land and plain on the last glacial stage demonstrating that time the climate was humid and cold. Judging from the pollen analyses of core QH70, the vegetational development and climatic changes in Fulaerji had been rapid since the Late Tertiary. It is more or less significance to use pollen analysis in hydrogeology and engineering geology.  相似文献   

17.
报道了新疆吐鲁番拗陷北部勒1、米1 、山1和墩1井中侏罗世孢粉化石52属81种.建立了本区中侏罗世孢粉组合: Cyathidites-Psophosphaera-Cycadopite 组合、 Cyathidites-Quadraeculina-Classopollis 组合和 Cyathidites-Callialasporites-Classopollis 组合.它们分别产自西山窑组、三间房组和七克台组.根据孢粉组合特征及其对比, 认为3个组合的地质时代属阿林-巴通期.经研究表明, 中侏罗世早期的植被是以银杏、苏铁类和松柏类等乔木为主体, 并伴有桫椤科树蕨及紫萁科和卷柏科等草本植物.古气候应属温暖潮湿的亚热带气候.至中侏罗世中晚期, 掌鳞杉科植物在植被中占主导地位, 指示当时的气候趋于干旱.  相似文献   

18.
狗鱼(Esox,Teleostei)化石在中国的首次发现   总被引:2,自引:0,他引:2  
记述了山东龙口黄县洼里煤矿早始新世黄县组二段油页岩中的鱼化石。该鱼身体狭长,背鳍位置靠后;额骨侧面有长形的、狗鱼所特有的副筛骨;额骨甚长;顶骨相对来说甚短;口裂较长;齿骨、前上颌骨及颚部许多骨片均生有扁而尖的牙齿,但上颌骨口缘光滑;外翼骨甚粗壮;鳃盖骨略呈长方形;前鳃盖骨较直,中部略收缩,上、下枝夹角大(约为130°);匙骨纵枝短而水平枝长大。困此属于狗鱼科中惟一的狗鱼属是毫无疑问的。根据其头长与体长之比、额骨及顶骨的形状和比例以及背鳍条数目与狗鱼属其他种的不同,我们将它订为一个新种——龙口狗鱼。黄县的化石是狗鱼渐新世以前在北美以外地区的首次发现,也是狗鱼化石在亚洲的首次发现。黄县位于北纬37°7′,远较现生狗鱼在亚洲分布的地区(43°和46°以北)靠南。而始新世全球气候偏暖,巨南北温差较小,始新世狗鱼或较现生种类更适应较温暖的气候。早始新世狗鱼在中国的发现为当时跨太平洋鱼类区系的存在提供了进一步的证据。  相似文献   

19.
One hundred and thirteen species of spores and pollens belonging to 58 genera were found from 66 core samples taken from two boreholes of the Early and Middle Jurassic deposits in the Qiquanhu coal-field of the Turpan Basin, Xinjiang have been investigated in this paper. Two of the species are described as new. Three sporo-pollen zones from lower to upper are described as follows: Sporo-pollen zone Ⅰ (equivalent bed: Badaowan Formation) . The pteridophytic spores are slightly more abundant than the gymnospermous pollen in this assemblage. The most abundant spores are Cyathidites minor, C. australis and Undulatisporites pflugii, U. taenus and so on. The second important fern spores are Osmundacidites, Lycopodiumsporites, Apiculatisporis and Duplexisporites. The most important gymnospermous genus is Cycadopites which ranks highest in the assemblage and includes C. nitidus and C. typicus.The other gymnospermous pollen include Classopollis, Pinuspollenites, Protoconiferus Piceites. Besides, there are a few pollen grains of Taeniaesporites and Chordasporites surviving from the Late Triassic in this assemblage. The present assemblage may be compared with the Early Jurassic sporopollen assemblage from the Daling Formation of the North-East Guangxi. Therefore, the Badaowan Formtion may be referred to Early Jurassic in age, probably Early Lias. Sporo-pollen zone Ⅱ (equivalent bed: Sangonghe Formation) In this assemblage the gymnosperms are predominant.Of them, Podocarpidites and Pinuspollenites increase obviously, and Quadraeculina and Protoconiferus are common. Few surviving elements are observed. The most abundant spores are those of Cyathidites, and the particularly abundant pollens are those of Cycadopites, This assemblage may be compared with the Late Lias sporo-pollen assemblage from the Fuxian Formation of the Northern Shangganning Basin. Therefore, the Sangonghe Formation should belong to Early Jurassic, probably Late Lias in age. Sporo-pollen zone Ⅲ (equivalent bed: Xishanyao Formation). The contents of the spores and pollens are almost equal in this assemblage. Cyathidites and Cycadopites are the most important spores and pollen. Osmundacidites and Quadraeculina are common. Neoraistrickia, Lycopodiumsporites and Eucommiidites troedssonii are present. Ancient striate bisaccate pollen disappears. The characteristics of this assemblage show some resemblances to those of the Middle Jurassic Yanan Formation in Chongxin county of Gansu province. So the Xishanyao Formation should belong to Middle Jurassic.  相似文献   

20.
A small assemblage of macro- and micro floral remains comprising fossil leaf impressions, silicified wood, spores, and pollen grains is reported from the Paleocene–lower Eocene Vagadkhol Formation (=Olpad Formation) exposed around Vagadkhol village in the Bharuch District of Gujarat, western India. The fossil leaves are represented by five genera and six species, namely, Polyalthia palaeosimiarum (Annonaceae), Acronychia siwalica (Rutaceae), Terminalia palaeocatapa and T. panandhroensis (Combretaceae), Lagerstroemia patelii (Lythraceae), and a new species, Gardenia vagadkholia (Rubiaceae). The lone fossil wood has been attributed to a new species, Schleicheroxylon bharuchense (Sapindaceae). The palynological assemblage, consisting of pollen grains and spores, comprises eleven taxa with more or less equal representation of pteridophytes, gymnosperms, and angiosperms. Angiospermous pollen grains include a new species Palmidites magnus. Spores are mostly pteridophytic but some fungal spores were also recovered. All the fossil species have been identified in the extant genera. The present day distribution of modern taxa comparable to the fossil assemblage recorded from the Vagadkhol area mostly indicate terrestrial lowland environment. Low frequency of pollen of two highland temperate taxa (Pinaceae) in the assemblage suggests that they may have been transported from a distant source. The wood and leaf taxa in the fossil assemblage are suggestive of tropical moist or wet forest with some deciduousness during the Paleocene–early Eocene. The presence of many fungal taxa further suggests the prevalence of enough humidity at the time of sedimentation.  相似文献   

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