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1.
海拉尔盆地查干诺尔凹陷扎赉诺尔群孢粉组合   总被引:3,自引:0,他引:3  
内蒙古自治区呼伦贝尔盟地区海拉尔盆地查干诺尔凹陷扎赉诺尔群自下而上划分为4个孢粉组合。云杉粉Piceaepollenites sp.-单束松粉Abietineaepollenites sp.-三角粒面孢Granulatisporites sp.组合,分布于大磨拐河组一段;罗汉松粉Podocarpidites sp.-双束松粉Pinuspollenites sp.-无突肋纹孢Cicatricosisporites sp.组合,分布于大磨拐河组二段;无突肋纹孢Cicatricosisporites sp.-刺毛孢Pilosisporite sp.-水龙骨单缝孢Polypodiaceaesporites sp.组合,分布于伊敏组一段;有突肋纹孢Appendicisporites sp.-桫椤孢Cyathidites sp.-星粉Astropollis sp.组合,分布于伊敏组二、三段。上述孢粉组合研究证明,大磨拐河组地质时代为早白垩世凡兰吟期—欧特里夫期(Valanginian-Hauterivian),尽管没有出现最原始的被子植物花粉,但也不排除部分进入巴列姆期(Barremian)的可能,伊敏组的地质时代为早白垩世巴列姆期-阿普第期(Barremian-Aptian)。据此认为扎赉诺尔群地质时代为早白垩世凡兰吟期—阿普第期(Valanginian-Aptian)。  相似文献   

2.
松辽盆地东南隆起区深部地层孢粉组合及其时代讨论   总被引:3,自引:1,他引:3  
裘松余 《吉林地质》1992,11(3):12-21
松辽盆地东南隆起区深部地层十分发育,含丰富的孢粉化石,所建立的4个孢粉组合,为地层划分对比和时代确定提供了生物地层学依据。火石岭组相当于晚侏罗世,沙河子组为早白垩世凡兰吟期至戈特里夫期,营城组为早白垩世巴列姆期,十屋组为早白垩世阿普第期。  相似文献   

3.
我国非海相白垩纪介形类化石可以划分为7个组合:1)分布于我国西北和西南地区欧特里沃期巴列姆期的Jingguella-Minheella-Pinnocypridea组合;2)分布于我国西北和西南地区巴列姆期的Cypridea-Latonia-Darwinula组合;3)阿普特期阿尔必期的Cypridea(Morinina)-Bisulcocypridea-Mongolocypris组合;4)分布于我国东北、中部及东部地区欧特里沃期巴列姆期的Cypridea-Mongolianella-Darwinula组合;5)分布于我国东北、中部及东部地区巴列姆期阿普特期的Cypridea(Cypridea)-Cypridea(Ulwellia)-Limnocypridea组合;6)塞诺曼期塞农期的Cypridea-Triangulicypris-Sunliavia-Lycopterocypris组合;7)坎潘期马斯特里赫特期的Talicypridea-Cypridea-Quadracypris-Candona组合。依据以上7个介形类化石组合,我国22个地区含介形类的73个地层单元(群/组)得到了对比。  相似文献   

4.
平凉安国镇六盘山群介形类   总被引:4,自引:0,他引:4  
李祖望 《甘肃地质》1995,4(2):10-21,T003
平凉安国镇六盘山群的介形类化石采自和尚堡组、李洼峡组与马东山组,计10属22种(含6新种、1新亚种、3未定种)。自下而上可分为:Cypridea(Ulwellia)-Damonella组合,时代属中上凡兰吟期;Cypridea(Cypridea)-Ziziphocypris组合,时代属豪特里维一巴列姆期及Cypridea-Liupanshania组合,时代属阿普第期。  相似文献   

5.
内蒙古海拉尔盆地大磨拐河组孢粉化石及其时代浅析   总被引:4,自引:0,他引:4  
海拉尔盆地大磨拐河组所产孢粉化石分属于3个孢粉组合.下部孢粉组合以蕨类植物海金沙科孢子为主,重要分子有Cicatricosisporites australiensis, Cyathidites minor, C. gracilis, C. minutaestriatus, Appendicisporites problematicus, A.jonsonii,Pilosisporites verus, Impardecispora apiverrucata, I. purverulenta, Triporoletes reticulates, Aequitriradites echinatus等;中部孢粉组合则以两气囊花粉如Pinuspollenites, Piceaepollenites, Abietineaepollenites, Abiespollenites等占绝大多数,同时见少量被子植物花粉Asteropollis sp., Tricolpites sp.等;上部孢粉组合中裸子植物花粉略有减少,但仍占重要地位,重要分子有Cicatricosisporites australiensis, C. minutaestriatus,C. gushanensis, Impardecispora purverulenta ,Foraminisporites wonthagiensis, Aequitriradites verrucosus, Triporoletes singularis, T. reticulates, Polyporites? sp.等.上述孢粉组合大体可与松辽盆地登娄库组,黑龙江省东部城子河组、穆棱组,辽西地区沙海组、阜新组等对比,代表了中国北方早白垩世特有的植物群面貌,而其中Asteropollis, Tricolpites和Polyporites等被子植物花粉化石的发现,可能暗示大磨拐河组的时代为早白垩世中、晚期的巴列姆(Barremian)期-阿普第(Aptian)期,其上部可能上延至早阿尔必(Albian)期.  相似文献   

6.
本文讨论了青海省唐古拉山地区风火山群的孢粉组合及时代,简述了地层层序及岩性特征。文中通过实际资料的对比,说明了风火山群孢粉组合的特点,同时指出风火山群既不属于晚白垩世也不是第三纪,而应归于早白垩世,置于早白垩世欧特里夫—巴列姆期更为合适。  相似文献   

7.
无论孢粉类型还是孢粉数量,昌五地区沙河子组发现的孢粉化石均可称得上是松辽盆地北部同层位中最丰富的。研究区沙河子组自下而上可以划分出两个孢粉组合:克拉梭粉(Classopollis)-拟云杉粉(Piceites)组合和三角瘤面孢(Lophotriletes)-无突肋纹孢(Cicatricosisporites)组合。其组合特征明显,可以作为研究区内地层划分对比的生物地层学依据之一。孢粉组合研究结果表明,沙河子组的地质时代应为早白垩世凡兰吟期-欧特里夫期(Valanginian-Hauterivian)。尽管没有出现最原始的被子植物花粉,但也不排除部分进入巴列姆期(Barremian)的可能。  相似文献   

8.
蛟河盆地内广泛出露下白垩统大拉子组,并在保家村附近产出介形虫、叶肢介和植物碎片等化石.通过1∶2 000地质剖面实测中分层采集化石,在保家村北侧剖面的大拉子组中获得介形虫5属9种,其中包括1个相似种和6个未定种,分别是:Cypridea paracavernosa,C. concinaformis,C. sp.,Candoniella cf. candida,Candoniella sp.,Scabriculocypris sp.,Mongolianella sp.,Candona sp. 1和Candona sp. 2.结合前人的化石发现,建立了Cypridea paracavernosa-C. concinaformis组合,该介形虫组合可以与吉林延边大拉子组介形虫进行对比,时代可能为早白垩世晚期.  相似文献   

9.
吉林省九台县羊草沟煤矿孢粉组合及时代   总被引:1,自引:0,他引:1  
本文介绍了羊草沟煤矿区的地层概况,对营城组和泉头组孢粉组合分子的基本特点,进行了详细地剖析,并与国内外已有研究成果作了对比。认为其时代均属于早白垩世,其中前者为巴列姆-阿普梯期,后者为阿尔必期。  相似文献   

10.
中国东部晚中生代广布的陆相火山盆地沉积,由于海相生物化石的匮乏造成与层型地区对比的困难,长期以来该地层时代仅笼统被认为属于晚侏罗世-早白垩世。通过岩石组合、构造层和沉积构造环境的综合对比,确立闽西地区的兜岭群与闽东地区南园群、浙西建德群可以对比,构造不整合面代表区域上由挤压向拉张构造背景转化的相对等时界面。兜岭群的植物群Cupressinocladus --Brachyphyllum 组合可能与北方的Ruffordia --Onychiopsis 植物组合大体相当,叶肢介、介形类、腹足类和双壳类等化石与浙江早白垩世建德生物群、北方的热河生物群均可以对比,时代应为早白垩世欧特里夫期-阿普特期。  相似文献   

11.
Defining the Jurassic-Cretaceous boundary is a controversy in stratigraphic study of the world. It has been widely accepted that this boundary can be defined at the bottom of Berriasian in Tethys, with the appearance of the ammonite Berriasella jacobi dating to ca. 145 Ma. However, it is difficult for the widespread terrestrial deposits in China to correlate with the international standard of marine facies. The Somanakamura Group in Japan is represented by a succession of marine-continental transitional strata. It provides a bridge of marine and nonmarine stratigraphic correlation. The ammonite and radiolarian fossils preserved in this group suggest an age from Bajocian to early Valanginian. The J-K boundary was defined in or atop the Tomizawa Formation of the group according to the ammonite data. The present authors study the fossil spores and pollen newly found from the Tomizawa and Koyamada formations. Three assemblages have been recognized. They are Assemblage 1 (Cyathidites-Classopollis) from the upper part of the Tomizawa Formation, Assemblage 2 (Cyathidites-Jiaohepollis) from the lower part of the Koyamada Formation, and Assemblage 3 (Cyathidites-Spheripollenites-Ephedripites) from the middle to upper part of the Koyamada Formation. With the reference of ammonite evidence, the J-K boundary can be defined between Assemblage 1 and Assemblage 2. This palynological J-K boundary can be correlated with that of terrestrial sequence in China. However, local biostratigraphy imply that the continental J-K boundary in China is of 135 or 137 Ma age. It has a considerable discrepancy from the marine standard. Biogeographically, the distribution pattern of spores and pollen in southern China is in accordance with that in the Somanakamura Group, which parallels the Tuchengzi Formation in northeastern China. By the palynological correlation between the Somanakamura Group and the strata in southern China, and then with the sequence in northeastern China, it is suggested that the continental J-K boundary is located in the Tuchengzi Formation.  相似文献   

12.
Marine and non-marine facies of the Permian–Triassic boundary stratigraphic set (PTBST) are well developed in South China. Palynological assemblages enable subdivision and correlation of the Permian–Triassic boundary (PTB) rocks. Three palynological assemblages are recognized across the PTBST in two terrestrial PTB sections in western Guizhou and eastern Yunnan, South China. Assemblage 1 (Xuanwei Formation) is a Late Permian palynological assemblage dominated by ferns and pteridosperms, with minor gymnosperms. Most taxa are typical long-ranging Paleozoic forms, but the appearance of Lueckisporites confirms a Late Permian age for this assemblage. Assemblage 2 (PTBST) is marked by an abrupt decrease in palynomorph abundance and diversity, and thriving fungal/algal(?) spores. Assemblage 2 is still dominated by ferns and pteridosperms, with a few gymnosperms, but is characterized by a mixed palynoflora containing both Late Permian and Early Triassic elements. Most taxa are typical Late Permian ones also found in Assemblage 1, however, some taxa of Early Triassic aspect, e.g. Lundbladispora and Taeniaesporites, appeared for the first time. In Assemblage 3 (top Xuanwei Formation and Kayitou Formation), the proportion of gymnosperm pollen increases rapidly, exceeding that of ferns and pteridosperms, but the abundance of palynomorphs is still low. Typical Early Triassic taxa (such as Lundbladispora, Aratrisporites and Taeniaesporites) are present in greater abundance and confirms an Early Triassic age for this assemblage.  相似文献   

13.
Yangtzeconus priscus-Archaeospira ornata, an important earliest Cambrian benthonic Assemblage of the Yangtze micromolluscan fauna, occurs mainly in the Lower Cambrian Zhongyicun and Dahai Members of the Yuhucun Formation in E Yunnan, the Tianzhushan Member (=Huangshandong Member) of the Dengying Formation in W Hubei and the Maidiping Member of the Hungchunping Formation in C Sichuan, China. About 90% of the genera of this Assemblage are unknown from the Nemakit-Daldynian and Tommotian molluscan Assemblages of the Siberian Platform, Russia. About 90% of the Siberian molluscan genera do not occur in the Zhongyicun and Dahai Members in the Meishucun section and in the corresponding beds of the Yangtze Platform, because the Tommotian molluscan Assemblage is characterizedly abundant archaeocyathids. It is clearly indicated that the Yangtze and Siberian molluscan Assemblages represent different bio- and lithofacies and ages. The age of the pre-trilobitic Yangtzeconus priscus-Archaeospira ornata Assemblage is older than that of the Nemakit-Daldynian and Tommotian molluscan Assemblages and referable to the Earliest Cambrian. Two new genera Mcnamaraconus and Zhangwentangoconus are herein proposed.  相似文献   

14.
江苏白垩纪孢粉组合序列   总被引:9,自引:5,他引:4  
根据近年来获得的孢粉化石材料和前人资料 ,建立了江苏白垩纪的孢粉组合序列 ,它们是 :  1)贝里阿斯期至凡兰吟期 (Berriasian— Valanginian)的 Schizaeoisporites- Classopollis annulatus- Ginkgocycadophytus nitidus组合 (云合山组 ) ;  2 )阿普特期至阿尔必期 (Aptian— Albian )的 Cicatricosisporites- Classopollis annulatus-Psilatricolpites组合 (葛村组 ) ;  3)土伦期 (Turonian )的 Schizaeoisporites- Polycingulatisporites- Cycadopites-Cranwellia组合 (浦口组 ) ;  4)科尼亚克期至桑顿期 (Coniacian— Santonian)的 Schizaeoisporites- Classopolisannulatus- Lytharites组合 (赤山组 ) ;  5 )坎潘期 (Campanian )的 Schizaeoisporites- Tricolporopollenitesmicrocirculatus- Betpakdalina组合 (泰州组下部 ) ;  6 )马斯特里赫特期 (Maastrichtian)的 Pterisisporites-Exesipollenites- K urtzipites组合 (泰州组上部 ) ; 欧特里沃期至巴列姆期 (Hauterivian— Barremian)和塞诺曼期(Cenom ainan)的暂缺。  相似文献   

15.
九陂组(亚田煤组)是粤北和湘南晚二叠世重要的含煤地层,其下伏"梅田灰岩"的涵义和(虫筵)化石Gallowayinella meitienensis的层位问题曾长期未得澄清.通过对梅田组剖面的详细工作,建立了下部的Gallowayinella组合和上部的Nanlingella jiaozishanica-Sphaerul...  相似文献   

16.
对渤海莱州湾南岸央子镇YZ1钻孔取微体古生物样品18个,通过分析鉴定和地层对比,以及对微体古生物化石进行属种、丰度和分异度分析,共划分出4个化石组合层段。根据化石组合特征分析认为:第Ⅰ、第Ⅱ微体化石组合为全新世海侵的产物。第Ⅰ组合代表了海进序列,沉积环境为潮上带—潮间带;第Ⅱ组合为海退序列,沉积环境为潮间带—潮下带。第Ⅲ、第Ⅳ组合分别是晚更新世2次海侵的产物。第Ⅲ组合为晚更新世末期海侵的产物,海侵规模较大,沉积环境为滨海潮坪—潮间带;第Ⅳ组合海侵规模较小,陆相因素增大,沉积环境为河口—滨岸带或者为海陆交互相。  相似文献   

17.
依据丰富翔实的地层古生物资料,首次在内蒙古西部建立了比较完整的第三纪地层层序:命名或厘订了中始新统乌兰乌珠尔组、上始新统查干布拉格组、下渐新统乌兰塔塔尔组、上渐新统、下中新统乌尔图组、上中新统呼和好来组和上新统昂冈浩特组等7个地层单元;区分出了中始新世乌兰乌珠尔、晚始新世查干布拉格、早渐新世早期克克阿木、早渐新世晚期乌兰塔塔尔、晚渐新世因德里沟、早中新世乌尔图、晚中新世呼和好来和上新世昂冈浩特等8个动物群(组合)。  相似文献   

18.
Quantitative analyses of palynomorph assemblages, particulate organic matter (kerogen), and total organic carbon (TOC) have been made on samples of the Albian–Cenomanian Kharita and Bahariya formations encountered in the Abu Gharadig-5 well, Western Desert, Egypt. Two assemblage palynozones are defined: Assemblage Zone A (Kharita Formation) of late Albian–early Cenomanian age and Assemblage Zone B (Bahariya Formation) of early–middle Cenomanian age. Palynofacies of the Kharita Formation suggest that sedimentation of these strata took place in a warm, shallow, nearshore-marine environment. The deposition of the lower Bahariya Formation took place initially in similar conditions but subsequently further offshore in somewhat deeper water of the inner shelf. The relatively high percentage of Ephedripites, Afropollis and elaterate pollen in both formations indicates an arid climate. The Kharita Formation yields kerogen types III and IV whereas the assemblages recovered from the Bahariya Formation contain types II and III. The TOC is generally between 0.42 and 0.65% in the Kharita Formation, while it ranges between 0.42 and 0.80% in samples of the Bahariya Formation. The spores and pollen grains are pale in colour; hence little source potential for hydrocarbons is indicated.  相似文献   

19.
柴达木盆地北缘沉积凝灰质岩层段的地层时代   总被引:2,自引:0,他引:2  
门相勇  李伟  席萍  唐伦和 《地质科学》2001,36(2):229-233
柴达木盆地北缘深部沉积凝灰质岩层段的地层归属存在2种观点,下侏罗统和石炭系。本文通过岩石薄片、微量元素、孢粉组合以及海相化石碎片等多种资料的综合分析,认为沉积凝灰质岩层段与其上的下侏罗统之间岩性、电性出现突变的主要原因是沉积时火山事件以及晚期方解石脉充填造成的,并不能代表下伏的老地层;沉积凝灰质岩层段的海相化石碎片为搬运再沉积的结果,没有地层指示意义;孢粉组合能反映沉积凝灰质岩层段沉积的地质年代,据此确认沉积凝灰质岩层段为下侏罗统湖西山组二段。  相似文献   

20.
郭宪璞 《地层学杂志》1995,19(3):208-213,T001
通过对新发现于新疆塔里木盆地西部上白垩统乌依塔克组有孔虫化石的时代分析,认为该组的时限为晚上伦期—赛诺期,综合分析各类化石的时代特征,本区土伦阶和赛诺阶的界线应划在Migros-Ammobaculites组合和Pararotalia-Nonionella组合之间。  相似文献   

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