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1.
辽宁凌源及相邻内蒙古南部宁城地区义县组发现多个重要脊椎动物化石地点,通过岩 石地层、脊椎动物生物地层和同位素年代地层对比,建立了该地区义县组地层层序。凌源一宁 城地区义县组有 2个脊椎动物化石层位:下部道虎沟层含 Lycopteraer Ichthyofauna, Psittacosaurus Fauna和Confuciusornis Avifauna等3个动物群,可以与北票尖山沟层的四合 屯脊椎动物化石群对比,层位相当于义县组一、三段;上部大王杖子(大新房子)层含 Lycoptera Ichthyofauna和Liaoxiornis Avifauna等2个动物群,为义县组中部沉积,在四合屯地 区缺失。冀北丰宁四岔口-森吉图地区义县组脊椎动物化石层对应于凌源大王杖子层;滦平 大北沟组为义县组最下部沉积,其上覆的大店子组相当于宁城道虎沟层和北票四合屯义县组 一、三段。热河群义县组和九佛堂组发现3个连续的鸟类群;义县组下部Confuciusornis Avifauna、义县组中部Liaoxiornis Avifauna和九佛堂组Cathayornis-Chaoyangia Avifauna。义 县组和九佛堂组Lycoptera I  相似文献   

2.
冀辽一带的土城子组和大北沟组对中国北方侏罗系–白垩系划分对比具有重要的意义。关于它们的时代目前还存在不同的看法,相关的孢粉地层学研究也比较粗略。本文研究了冀北滦平县井上村三岔子剖面土城子组和大北沟组的孢粉组合,共观察统计到50属28种及若干未定种。土城子组Classopollis–Cooksonites–Ephedripites组合以Classopollis含量最为突出,同时含有白垩纪分子Cooksonitesvariabilis、Crybelosporitespunctatus和Ephedripites(E.),其时代为早白垩世Berriasian期。大北沟组Bisaccates–Foraminisporis组合以松柏类两气囊花粉占绝对优势,见有Crybelosporites punctatus、Ephedripites (E.) crassistriatus、Foraminisporis wonthaggiensis、Jiaohepollis和Rugubivesiculites spherisaccatus等具有时代意义的分子,其时代为早白垩世Valanginian中–晚期。本研究首次报道了土城子组一段顶部的早白垩世孢粉组合,提出了中国北方侏罗系–白垩系界线位于土城子组一段内的新意见。孢粉组合对比表明当前冀北滦平盆地大北沟组Bisaccates–Foraminisporis组合与辽西金岭寺–羊山盆地土城子组三段顶部及其上覆义县组下部的孢粉组合非常相似。因此,从孢粉植物群的发育来看,滦平盆地大北沟组可能与金岭寺–羊山盆地土城子组三段顶部至义县组下部相当。  相似文献   

3.
辽西义县组孢粉植物群指示的古气候条件   总被引:4,自引:0,他引:4  
迄今为止,在辽西北票义县地区的下白垩统义县组二段沉积层中,已发现孢粉化石62属,82种,藻类化石3种。本文对产于不同地点沉积层中的孢粉化石进行了系统研究和总结。根据孢粉母体植物形态和生态特征、生长的气候环境和干湿度环境,对义县组二段的孢粉植物群进行了植被类型、气候带类型和干湿度类型的统计和划分,认为义县组二段沉积时期,其孢粉植被类型为针叶林,所处的气候环境为湿润的亚热带一暖温带。由于植被成分中存在落叶阔叶植物和旱生植物,推测气候环境存在季节性变化,间有干旱一半干旱气候条件。  相似文献   

4.
吉林安图县早白垩世屯田营组孢粉组合   总被引:7,自引:0,他引:7  
黎文本 《古生物学报》2001,40(4):450-456
吉林省安县明月镇屯田营组上部的孢粉化石组合以含大量松柏类各种两气囊花粉,伴以少量Schizaeoisportes,Fixisporites,Cicatricosisporites等属孢子为特征,组合面貌与辽西义县组下部尖山沟层的组合一致,时代属早白垩世贝利亚斯期,整个屯田营组只相当于义县组的下部,缺乏与义县组上部相当的地层。  相似文献   

5.
本文研究了辽西北票四合屯脊椎动物化石产地附近土城子组三段的孢粉组合,共计32属9种及25未定种。孢粉组合以松柏类两气囊花粉占绝对优势,三缝孢子含量低。当前组合中见有Cicatricosisporites,Lygodioisporites,Jiaohepollis,Rugubivesiculites等早白垩世特征分子,同时未见被子植物花粉,推测其时代为早白垩世早期,这与同位素测年结果相一致。这一孢粉组合以松柏类两气囊花粉的高含量及Classopollis的低含量为特征,明显不同于以往报道的土城子组的孢粉组合,却与辽西地区义县组下部层段的孢粉组合非常相似,表明辽西地区土城子组沉积的末期区域植物群面貌与义县组已无本质差别,尽管两套地层在岩相和沉积上差异明显。这一发现提示我们,土城子组的横向对比对于正确重建中国北方侏罗纪—白垩纪早期的沉积演化史十分关键,有必要在后续研究中进一步开展其他地区土城子组的孢粉等生物地层及区域间的对比工作。  相似文献   

6.
热河生物群的翼龙都发现于义县组和九佛堂组。金刚山层位于义县组上部,已经报道的翼龙包括最早发现的两件翼龙胚胎,两件古翼手龙超科的标本,以及一件存疑的金刚山义县翼龙。对这一层位发现的一件前肢标本进行了描述,并确定其属于无齿翼龙超科。对现存于本溪地质博物馆的金刚山义县翼龙的正型标本进行了观察,并修订其鉴定特征。无齿翼龙超科成员具有独有的特征组合为:牙齿垂直于咬合面,呈三角形且唇舌向扁,前两对更长更细;第二翼指骨长度约为第一翼指骨的93%。在热河生物群中,古翼手龙超科的标本主要发现于义县组,而古神翼龙超科主要发现于九佛堂组。包括这件新标本和金刚山义县翼龙在内的无齿翼龙超科在九佛堂组发现的略多于义县组,这与之前认为的翼龙分布情况不同。  相似文献   

7.
本文对南海北部珠江口盆地深水区LW5井3 070—3 480m井段81个孢粉样品进行了分析,共鉴定86个孢粉属种类型;另有沟鞭藻和有孔虫内膜。根据孢粉和藻类化石组合面貌、丰度变化和特征分子的分布规律,将研究井段地层划分为2个孢粉组合:3 070—3 325m井段为Polypodiaceaesporites-Dinocysts组合,层位相当于珠江组,时代为早中新世。本组合含丰富的沟鞭藻和微有孔虫,孢粉以Graminidites,Zonocostatites和Chenopodipollis等为主,沉积环境为滨浅海,气温较高,指示了湿润的热带、亚热带古气候;3 330—3 470m井段为AlnipollenitesPinuspollenites组合,与珠海组层位相当,地层时代为晚渐新世。本组合沟鞭藻和微有孔虫少量出现,孢粉含丰富的Pinuspollenites和Abietineaepollenites,出现较多的Cedripites等,反映海陆交互的古环境,显示了气温低的亚热带古气候。  相似文献   

8.
甘肃玉门旱峡早白垩世孢粉组合   总被引:4,自引:1,他引:3  
本文研究了甘肃玉门旱峡沟口剖面下沟组,中沟组的孢粉化石,共鉴定孢粉37属53种;藻类化石2属2种。根据上孢粉化石建立了Cicatricosisporites-Schizaeoisporites-Classopollis-Jiaohepollis组合,包括下亚组合,包括下晋组合(下沟组)和上亚组合(中沟组)。鉴定组合地质时代为Hauteriv-ian-Barremian。推测气候属于温暖湿润的亚热带  相似文献   

9.
渤海海域渤东凹陷沙河街组四段内发现了丰富的孢粉、藻类和轮藻类化石组合,孢粉组合与渤海湾沿岸地区沙河街组四段的E phedri pites-Ulmoidei pites tricostatus-Pterisis porites组合特征一致,沟鞭藻类见有Luxadinium elongatum,Cangaianella e...  相似文献   

10.
内蒙古宁城道虎沟村一带是著名的道虎沟生物群的代表性产地,本文对这里的柳树湾剖面海房沟组进行了孢粉分析,揭示了道虎沟生物群发育的古植被组成面貌,为研究这一中国北方中、晚侏罗世重要生物群的生态系统及演化提供了重要信息。当前样品含有数量丰富的孢子花粉化石,但分异度不高,共计20属15种及若干未定种。孢粉组合以裸子植物两气囊花粉占优势为特征,其中以Alisporites和Pseudopicea含量最突出,其次为Quadraeculina和Podocarpidites。掌鳞杉类Classopollis常见,蕨类和苔藓孢子则非常匮乏。孢粉组合的时代很可能为中侏罗世末,但也不排除至晚侏罗世早期的可能。孢粉组合显示道虎沟生物群发育时期研究区的植被为以裸子植物松柏类针叶林为主的景观,气候温凉、湿度中等。  相似文献   

11.
The Red Beds of Nandian consists mainly of red mud stone, marlite, quartzitic sand- stanc, Sabulous psephyte and fine psephyte. Predecessor divided them into three formations referring to Upper Triassic-Jurassic. The marlite in Upper Formation of the Red Beds are rich in fossil Sporo-pollen. The fossil spores and pollen contain 17 genera and 15 species, including 3 new species and 2 new combinations. The Sporo-pollen assemblage is characterized by the absolut predominance of the pollen of gymnospcrms (84.8%) compared with the spores of pteridophyta (15.2%), The pollen are specially characterized by the abundance of Classeopollis Pfiug (75.3%) with a certain amount of Psophosphaera (4.5%), Monosulites (2.4%) and a minority of Pinuspollenites (0.6%). The spores grains are characterized by the abundance of Cyathidites (4.1%), and also by presence of Calamospora (2.1%), Reticulatisporitcs (2.4%), Indeterminable form (1.2%), and rare Schizaeisporites (0.3%). Based on the sporo-pollen assemblage of Upper Jurrassic of the Eurasia continent is characterized by the absolute abundance of Classpollis Pflug (>50% of the total number), the Upper Formation oi the Red Beds of Nandian may be referred to Upper Jurassic age. The climate of the Nandian region in the Late Jurassic period is supposed to be as arid as that of Africa at the present time. Bundary of the eastern termination of southern part of the Eurasia continent in- ferred by Vakhrameev (1970) should be complemented.  相似文献   

12.
曹正尧 《古生物学报》2001,40(2):214-218
报道辽西义县组两种颇具地层意义的植物化石。Ruffordia goeppertii(Dunker)Seward和Nageiopsis exgr.samioides(Fontaine)berry,根据植物化石认为义县组的时代应属于早白垩世。  相似文献   

13.
辽宁西部晚中生代地层的综合层序为:义县组、九佛堂组、沙海组/张老公屯组、阜新组和孙家湾组.中西部朝阳—喀左—建昌以及凌源—三十家子盆地的义县组大致相当于东部阜新—义县—锦州盆地的狭义义县组及其底部的北票尖山含化石沉积夹层;中西部的九佛堂组则可与东部的金刚山、吐呼鲁和九佛堂三个岩组相对比;张老公屯组火山岩在层序上大部分可能位于九佛堂组和阜新组之间.以北票鲟、中华弓鳍鱼和狼鳍鱼为代表的鱼类化石普遍见于中国北方热河群及其相当岩群的下部河湖相地层中,以粒鳞鱼、固阳鱼和副狼鳍鱼为代表的鱼类化石多见于上部的扇三角洲和湖沼相含煤地层中.热河群及相当岩群时代的确定以及陆相侏罗—白垩系界线的厘定受制于目前地层和生物化石的研究程度.从鱼群的面貌看,义县—九佛堂组、沙海—阜新组及相当地层的时代可能分别为晚侏罗世晚期—早白垩世早期和早白垩世中期.  相似文献   

14.
辽宁早白垩世义县组一原始鸟脚类恐龙   总被引:11,自引:0,他引:11  
初步记述了采自辽西地区早白垩世义县组新的原始鸟脚类恐龙化石材料,并依此建立一新属新种上园热河龙(Jeholosaurus shangyuanensis gen. et sp. nov.)。化石产于北票市上园镇陆家屯义县组下部第一段灰白色凝灰质砂岩中,同一层位产出过大量鹦鹉嘴龙化石。上园热河龙的主要鉴定特征包括6个前上颌齿,鼻骨背面发育小孔,前齿骨约为前上颌骨主体长度的1.5倍、未发育股骨前髁间沟、骨不在一平面上,第三趾趾节中第四节最长。上园热河龙具有一些真鸟脚类恐龙的近裔性状,比如眶前孔小,方骨孔大,位于方颧骨侧面,外下颌孔缺失。另外,上园热河龙的股骨近端形态非常接近进步的鸟脚类恐龙。但是上园热河龙发育有6个前上颌齿,上下颌关节处与齿列位于同一水平线,前上颌齿列与上颌齿列位于同一水平线,这些原始特征未见于已知鸟脚类恐龙。上园热河龙确切系统分类位置需要进一步确定。 上园热河龙是义县组中发现的第二种鸟臀类恐龙,增加了这类恐龙在热河生物群中的分异度。  相似文献   

15.
The Yixian Formation of Liaoning Province, People's Republic of China has yielded a diverse fauna of non-avian dinosaurs, but is dominated by small-bodied taxa. Here, we describe a series of isolated teeth from the Lujiatun Beds of the formation that are referable to a basal titanosauriform sauropod. Some of the teeth possess a distinctive circular boss on the lingual surface, which suggests that they are referable to cf. Euhelopus sp. This identification provides some additional support for biostratigraphical correlations between the Jehol Group and the Mengyin Formation of Shandong Province that suggest an Early Cretaceous age for the latter unit. Moreover, the titanosauriform affinities of the teeth provide further evidence for the dominance of this sauropod clade in eastern Asia during the Cretaceous.  相似文献   

16.
辽西义县组长节锯蜂科(昆虫纲,膜翅目)昆虫化石   总被引:4,自引:0,他引:4  
描述产自辽宁西部北票上园地区和凌源大王杖子义县组长节锯蜂科(Xyelidae)巨长节锯蜂亚科(Macroxyelinae)昆虫化石12种,归于4族8属,其中6新属12新种,包括Angaridyela robusta sp.nov.,Angaridyela exculpta sp.nov.,Angaridyela suspecta sp.nov.,Angaridyela endemica sp.no  相似文献   

17.
Twenty-eight species (or forms) of fossil pollen and spores referred to 20 genera extracted from the crude oil samples collected from the Kuche Seg of the Talimu Basin in Xinjiang are observed. The conception of the petroleum sporopouen assemblage is further expounded and the classification of the petroleum sporo-pollen assemblage is also tentatively proposed. According to the characteristics of the assemblages, the problem on oil source of the mentioned oil-bearing region is discussed in this paper. The petroleum sporo-pollen assemblage of Jurassic reservoir of Kucbe Seg is composed of Deltoidospora perpusilla, D. gradata, Cyathidites minor, Hymenophyllumsporites deltoidus, Cingulatisporites problematicus, Cibotiumspora paradoxa, Osmundacidites ap., Cycadopites typicus, C. nitidus, Podocarpidites multesimus, Alisporites grandis, Alisporites bilateralis, Parvisaccites sp., Abietineaepollenites microalatus, A. minimus, PinuspoRenites sp., Piceaepollenites sp., etc. These species of spores and pollen have been found from the Jurassic deposits in this region or in the adjacent regions. The petroleum sporo-pollen assemblage only contains the spores and pollen which coincide with those of the reservoir in age. There is not any spore or pollen older or younger than the reservoir. Consequently, it may be referred to a monotonous type of petroleum sporo-pollen assemblage. The petroleum sporo-pollen assemblage of Cretaceous reservoir of this region consists of Deltoidospora perpusilla, Cryathidites minor, Cibotiumspora paradoxa, Schizaeoisporites zizyphinus, Osmundacidites sp., Crcadopites typicus, C. nitidus, Parvisaccites sp., Cedripites cretaceus, Abietineaepollenites microalatus, A. minimus, Pinuspollenites sp., etc. All these species distribute either in the Jurassic deposits or in the Cretaceous deposits in this region or in the adjacent regions. The distribution of Schizaeoisporites zizyphinus and Cedripites cretaceus is usually limited to the Cretaceous deposits. Both the Cretaceous species and the Jurassic species are comprised in the assemblage, so it may be referred to a composite type of petroleum sporo-pollen assemblage. The petroleum sporo-pollen assemblage of Tertiary reservoir comprises Deltoidospora perpusilla, Cyathidites minor, Cibotiumspora paradoxa, Schizaeoisporites zizyphinus, Poly-podiaceaesporites sp., Cycadopites nitidus, Podocarpidites multesimus, Parvisaccites sp., Abietineaepollenites mininus, Pinuspollenites labdacus, Piceaepollenites alatus, Cedripites ovatus, Ephedripites fusiformis, Quercoidites microhenrici, Chenopodipollis multiporatus, C. microporatus, Artemisiaepollenites sdlularis, etc. Besides the Tertiary pollen and spores, the assemblage contains the Jurassic species and the Cretaceous species, and therefore it belongs to a composite type of petroleum sporo-pollen assemblage. The monotonous type of petroleum sporo-pollen assemblage reflects that the oil source rock is coincident with the reservoir rock in age, and the composite type of petroleum sporopollen assemblage shows that the oil source rock is generally older than the reservoir rock. Based on the investigation of the petroleum sporo-pollen assemblages, the oil source rock of the Kuche Seg is considered to be Jurassic Period in age, and the Lower Jurassic Yangxia Formation and the Middle Jurassic Kuzilenuer Formation are considered to be favorable source rock. The conclusion is supported by the result of the organic geochemical investigation.  相似文献   

18.
辽宁早白垩世义县组一新的三尖齿兽类   总被引:2,自引:1,他引:1  
描述了戈壁锥齿兽科 (Gobiconodontidae)一个新的属种———陆家屯弥曼齿兽 (Meeman nodonlujiatunensisgen .etsp .nov.)。标本产于辽宁西部朝阳市上园镇陆家屯下白垩统义县组一段的凝灰质砂岩层中 ,为一具完整齿列的左下颌骨。新属与戈壁锥齿兽 (Gobiconodon)共有以下区别于其他三尖齿兽类的特征 :2颗下门齿 ,i1增大 ,后部门齿、犬齿和前部前臼齿尖锥形 ,前臼齿具有高的中央尖和小的附尖 ,i~p1向前平伏。因此 ,新属被归入戈壁锥齿兽科。弥曼齿兽与戈壁锥齿兽及其相近属的区别在于 :下门齿和下犬齿更加平伏 ,i1在比例上更大 ,而i2则更小 ;最后一枚下前臼齿与第一枚下臼齿之间没有齿隙 ;前臼齿退化 ;下臼齿长度大于高度 ,主尖向后倾斜 ,与b尖和c尖相比 ,a尖较低 ,m1显著小于m2~ 4。新属下臼齿没有齿带 ,与爬兽 (Repenomamus)相似 ,而与戈壁锥齿兽不同。基于与爬兽齿列的对比 ,讨论了戈壁锥齿兽类的齿式 ,认为其应具有两颗门齿 ,而不是以前认为的 1颗门齿 ,从而将戈壁锥齿兽类下齿列齿式修订为 :2·1·2~ 3·5。  相似文献   

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