共查询到20条相似文献，搜索用时 109 毫秒
1.
2.
山东济宁煤田(东区)晚古生代孢粉组合 总被引：7，自引：0，他引：7
鉴定了山东济宁煤田(东区)晚古生代孢粉组合中的孢粉化石70属189种.据孢粉化石在地层中的分布和垂向的变化规律自上而下建立了5个孢粉组合:Ⅴ. Cyclogranisporites pressus-Lycospora pellucida组合, Ⅳ. Granulatisporites piroformis组合,Ⅲ. Sinulatisporites sinensis组合,Ⅱ. Thymospora pseudothiessenii-T. thiessenii组合,Ⅰ. Densosporites annulatus组合.通过与邻区及华北部分地区对比,确定本区孢粉组合的地质时代应为:晚石炭世晚期(组合Ⅰ),早二叠世早期(组合Ⅱ),早二叠世中期(组合Ⅲ),早二叠世晚期(组合Ⅳ)和晚二叠世早期(组合Ⅴ),本区石炭系-二叠系界线应置于太原组第11层灰岩之底. 相似文献
3.
辽宁北部秀水盆地秀D1井孢粉组合及其地层意义 总被引：2，自引：1，他引：1
孢粉化石采自辽宁省北部秀水盆地的秀D1井,分析、鉴定和系统研究结果表明,来自秀D1井井深62.1~1089.7m的孢粉化石自下而上划分为3个孢粉组合,下部孢粉组合(井深703.85~1089.7m)以Osmundacidites-Klukisporites-Podocarpidites为代表,地质时代为晚侏罗世堤塘期(Tithonian),中部孢粉组合(井深381.5~699.3m)以Densoisporites-Cicatricosisporites-Piceaepollenites为代表,地质时代为早白垩世贝里阿斯期(Berriassian),上部孢粉组合(井深62.1~339m)以Cicatricosisporites-Impardecispora-Pinuspollenites为代表,地质时代为早白垩世凡兰吟期—欧特里夫期(Valanginian-Hauterivian)。秀D1井钻遇地层所含孢粉组合特征在区域上可以与冀北地区大北沟组,辽宁西部地区下白垩统义县组、九佛堂组,松辽盆地东南缘下白垩统火石岭组、沙河子组所产的孢粉组合对比。含孢粉组合地层时代的确定解决了井柱地层的划分,以及与区域地层的对比关系,同时为区域地层古生物研究提供了翔实的基础资料。 相似文献
4.
首次在松辽盆地北部黑富地1井上二叠统四站板岩组采获孢粉化石,称为Protohaploxypinus fertilis-Piceaepollenites opimus-Alisporites communis组合,该组合裸子植物花粉占绝对优势地位,蕨类植物孢子含量低且属种贫乏. 裸子植物花粉以无肋双囊粉含量最多,其次为具肋双囊粉,单气囊花粉含量较少,可与新疆北部准噶尔盆地、塔里木盆地晚二叠世和大兴安岭地区林西组孢粉组合对比,时代为晚二叠世. 孢粉化石赋存井段岩性组合特征与林西组相似,因此松辽盆地西部大兴安岭地区的林西组可引入松辽盆地内, 原四站板岩组改称林西组. 相似文献
5.
本文主要对山东彭庄煤矿西补15井太原组上部以及山西组进行采样研究,共分析孢粉样品14块,所有样品中均含有较为丰富的孢粉化石;经分析鉴定,共发现孢粉化石37属107种及部分未定种;根据孢粉化石在地层中的纵向分布规律及其含量变化,自下而上建立两个孢粉组合：Ⅰ.Laevigatosporites Granulatisporites组合（太原组上部）,Ⅱ.Gulisporites cochlearius Leiotriletes adnatus Sinulatisporites sinensis组合（山西组）;并将本区孢粉组合特征与华北其他地区进行了比较;明确了本区孢粉组合的地质时代,组合Ⅰ为早二叠世晚期,组合Ⅱ为中二叠世早期,即本区下、中二叠统界线应置于山西组底部泥岩之底;最后,根据孢粉特征恢复了相应地质时期的古气候,继而进一步佐证了本区下、中二叠统界线。 相似文献
6.
豫西宜阳上二叠统孙家沟组为一套陆相碎屑岩,在该组中部土门段砂泥互层中发现大量的植物化石碎片和孢粉化石。文中依据孙家沟组沉积特征及孢粉组合区域对比,厘定了土门段的地质时代,并依据孢粉化石的亲缘植物关系和信息函数,结合微量元素Sr/Cu值指标,定性和半定量分析了宜阳地区的古气候特征。结果显示: 土门段共发现52属孢粉化石,以裸子植物花粉占优势,与华北地区晚二叠世孢粉组合特征有很大的相似性,推测其地质时代相当于晚二叠世长兴期。孢粉化石属种的植物亲缘关系与欧美镁灰岩统植物成分类似,表明整体上为较炎热的半干旱古气候。该成果可为华北地区晚二叠世晚期的陆相沉积环境、古植物背景以及古气候演化研究提供参考依据。 相似文献
7.
《古地理学报》2021,23(5)
豫西宜阳上二叠统孙家沟组为一套陆相碎屑岩,在该组中部土门段砂泥互层中发现大量的植物化石碎片和孢粉化石。文中依据孙家沟组沉积特征及孢粉组合区域对比,厘定了土门段的地质时代,并依据孢粉化石的亲缘植物关系和信息函数,结合微量元素Sr/Cu值指标,定性和半定量分析了宜阳地区的古气候特征。结果显示:土门段共发现52属孢粉化石,以裸子植物花粉占优势,与华北地区晚二叠世孢粉组合特征有很大的相似性,推测其地质时代相当于晚二叠世长兴期。孢粉化石属种的植物亲缘关系与欧美镁灰岩统植物成分类似,表明整体上为较炎热的半干旱古气候。该成果可为华北地区晚二叠世晚期的陆相沉积环境、古植物背景以及古气候演化研究提供参考依据。 相似文献
8.
重庆云阳新田沟组恐龙动物群是四川盆地近年来新发现的恐龙动物群,动物群埋藏层位为新田沟组中上部.对云阳地区恐龙化石埋藏地新田沟组剖面自底到顶系统开展了孢粉化石采样分析工作,分析结果表明,新田沟组上部孢粉化石缺失,中下部孢粉化石含量丰富,裸子植物花粉在孢粉组合中占绝对优势,含量高达91.64％,苔藓、蕨类植物孢子含量较低,为8.36％,未见被子植物花粉.裸子植物花粉中以无气囊类为主,占孢粉组合的81.99％,蕨类植物以无环光面或近光面的三缝孢子为主,占孢粉组合的5.49％.孢粉组合特征表明,研究区新田沟组时代为中侏罗世早期,属于热带—亚热带半干旱—半潮湿气候区. 相似文献
9.
海拉尔盆地海参1井伊敏组孢粉组合的地层意义 总被引：3，自引：0，他引：3
海参1井伊敏组孢粉化石异常丰富,自下而上可以划分出3个孢粉组合:Impardecispora-Cyathidites-Clavatipollenites组合,Stereisporites-Deltoidospora-Asteropollis组合,Appendicisporites-Asteropollis-Tricolpites组合,分别分布于伊敏组一段、二段和三段,组合特征明显,是海拉尔盆地乌尔逊凹陷划分伊敏组与大磨拐河组的重要生物依据之一,更是伊敏组内三段划分和井间对比的生物依据之一。3个孢粉组合中见有属种繁多的海金沙科孢子及其他繁盛于早白垩世中晚期的孢子花粉,结合在绝大多数样品中发现的早期被子植物花粉的情况分析,推测含这3个孢粉组合的伊敏组地质时代为早白垩世巴列姆期—早阿尔必期(Barremian—Early Albian)。 相似文献
10.
11.
海南岛大岭地区二叠系的发现及意义 总被引：4，自引：0，他引：4
测制大岭农场１４—１２队剖面时,在覆于相当昌江鸡实含Ｐｓｅｕｄｏｕｒａｌｉｎｉａ带岩关阶地层之上的千枚岩中,首次发现菊石Ａｌｔｕｄｏｃｅｒａｓｓｐ．、Ａｇａｔｈｉｃｅｒａｓｃｆ．ｖｕｌｇａｔｕｍ;河叉岭剖面首次发现牙形刺Ｎｅｏｇｏｎｄｏｌｅｌａ？ｓｐ．;在邦溪农场八队绢云母千枚岩中,第一次分析出以三缝孢子占优势的孢粉组合。据此,笔者认为大岭地区的晚古生代地层,除有下石炭统岩关阶地层外,还有二叠纪地层,并可与邻区二叠纪地层对比,并探讨了该区二叠纪岩相古地理。 相似文献
12.
I. Metcalfe C.B. Foster S.A. Afonin R.S. Nicoll R. Mundil Wang Xiaofeng S.G. Lucas 《Journal of Asian Earth Sciences》2009,36(6):503
Measured lithostratigraphic sections of the classic Permian–Triassic non-marine transitional sequences covering the upper Quanzijie, Wutonggou, Guodikeng and lower Jiucaiyuan Formations at Dalongkou and Lucaogou, Xinjiang Province, China are presented. These measured sections form the framework and reference sections for a range of multi-disciplinary studies of the P–T transition in this large ancient lake basin, including palynostratigraphy, vertebrate biostratigraphy, chemostratigraphy and magnetostratigraphy. The 121 m thick Wutonggou Formation at Dalongkou includes 12 sandstone units ranging in thickness from 0.5 to 10.5 m that represent cyclical coarse terrigenous input to the lake basin during the Late Permian. The rhythmically-bedded, mudstone-dominated Guodikeng Formation is 197 m and 209 m thick on the north and south limbs of the Dalongkou anticline, respectively, and 129 m thick at Lucaogou. Based on limited palynological data, the Permian–Triassic boundary was previously placed approximately 50 m below the top of this formation at Dalongkou. This boundary does not coincide with any mappable lithologic unit, such as the basal sandstones of the overlying Jiucaiyuan Formation, assigned to the Early Triassic. The presence of multiple organic δ13C-isotope excursions, mutant pollen, and multiple algal and conchostracan blooms in this formation, together with Late Permian palynomorphs, suggests that the Guodikeng Formation records multiple climatic perturbation signals representing environmental stress during the late Permian mass extinction interval. The overlap between the vertebrates Dicynodon and Lystrosaurus in the upper part of this formation, and the occurrence of late Permian spores and the latest Permian to earliest Triassic megaspore Otynisporites eotriassicus is consistent with a latest Permian age for at least part of the Guodikeng Formation. Palynostratigrahic placement of the Permian–Triassic boundary in the Junggar Basin remains problematic because key miospore taxa, such as Aratrisporites spp. are not present. Palynomorphs from the Guodikeng are assigned to two assemblages; the youngest, from the upper 100 m of the formation (and the overlying Jiucaiyuan Formation), contains both typical Permian elements and distinctive taxa that elsewhere are known from the Early Triassic of Canada, Greenland, Norway, and Russia. The latter include spores assigned to Pechorosporites disertus, Lundbladispora foveota, Naumovaspora striata, Decussatisporites mulstrigatus and Leptolepidites jonkerii. While the presence of Devonian and Carboniferous spores and Early Permian pollen demonstrate reworking is occurring in the Guodikeng assemblages, the sometimes common occurrence of Scutasporites sp. cf. Scutasporites unicus, and other pollen, suggests that the Late Permian elements are in place, and that the upper assemblage derives from a genuine transitional flora of Early Triassic aspect. In the Junggar Basin, biostratigraphic data and magnetostratigraphic data indicate that the Permian–Triassic boundary (GSSP Level) is in the middle to upper Guodikeng Formation and perhaps as high as the formational contact with the overlying Jiucaiyuan Formation. 相似文献
13.
陕西岐山产Eumorphotis的“石千峰组”地层问题 总被引：3，自引：0，他引：3
<正> “石千峰群”的问题,是涉及华北及其相邻广大地区陆相二—三叠系划分、对比及界线的重大地层课题,自下而上分为石千峰组(孙家沟组)、刘家沟组、和尚沟组。并确认石千峰组含有晚二叠世的Lueckisporites-Protohaploxypinus 孢粉组合;Abiella sp., Microdontella sp.等瓣鳃类;Sinolimnadiopsis yaoxianensis, Huanghestheria longellipsa等叶肢介;Shihtienfenia permica, Shansisaurus xuecunensis, Tapinocephalidae等脊椎动物化石。刘家沟组含早三叠 相似文献
14.
西藏西部狮泉河地区二叠纪和三叠纪牙形石的发现及其意义 总被引：2，自引：3，他引：2
西藏西部阿里狮泉河地区的昂杰组、下拉组和左左组中发现牙形石化石。昂杰组的牙形石组合大致对比于中二叠世空谷期早中期Mesogondolella idahoensis-Vjalovognathus shindyensis组合带。下拉组顶部的牙形石组合大致对比于晚二叠世长兴期晚期Clarkina changxingensis带。左左组中含有早三叠世的Neospathodus sp.和Gladigondolella sp.,左左组和下拉组整合接触,左左组主体时代为三叠纪。狮泉河地区在早二叠世末期就开始由冈瓦纳相碎屑岩沉积转变为特提斯相碳酸盐岩沉积,在晚二叠世长兴期和早三叠世依然维持在海相沉积环境中。冈底斯西部在晚二叠世和三叠纪为古陆的观点有待于重新审视。 相似文献
15.
新疆拜城阿合组、阳霞组及克孜勒努尔组的孢粉组合 总被引：6，自引：0，他引：6
拜城地区中生代陆相地层非常发育.作者在阿合组、阳霞组和克孜勒努尔组中获得了不少的孢粉化石,共鉴定有58属,93种,其中2新种和2新联合种. 相似文献
16.
藏北申扎地区上二叠统木纠错组的建立及皱纹珊瑚组合 总被引：5，自引：6，他引：5
在申扎县城东南木纠错南东岸附近发现一套巨厚的以白云岩、白云质灰岩为主组成的岩系,厚达2348m。该岩系整合覆于下二叠统下拉组之上,并于其底部发现中国南方晚二叠世早期珊瑚动物群中的重要分子WaagenophyllumindicumcrassiseptatumWu和LiangshanophyllumstreptoseptatumWang两种,与其共生的还有Lobatophyllumzakan-genseWu和WaagenophyllummegacolumetumWu,它们共同组成一个晚二叠世早期特有的皱纹珊瑚动物组合,命名为Waagenophyllum-Liangshanophyllum-Lobatophyllum组合。将含有这一珊瑚化石组合的以白云岩、白云质灰岩为主的岩系另建立新组———木纠错组,该组在层位上相当于中国南方上二叠统的吴家坪组。 相似文献
17.
Neerja Jha Pauline Sabina K. Rajni Tewari N. C. Mehrotra 《Journal of the Geological Society of India》2011,77(2):137-148
42 genera of palynomorphs have been reported from the qualitative and quantitative analysis of the palynoflora from both open
cast mine and bore holes viz., Ballarpur open cast mine, Durgapur open cast mine and Bore hole CMWNM-57 on barrier between
Kawadi/Majri open cast and Hindustan Lalpeth Colliery from the Wardha valley coalfield of Wardha basin. Two palynoassemblages
have been recorded i.e., an Upper Karharbari palynoassemblage comprising dominance of radial monosaccate genus Parasaccites and subdominance of nonstriate disaccate genus Scheuringipollenites and a Lower Barakar palynoassemblage consisting of dominance of Scheuringipollenites and subdominance of striate disaccates chiefly Faunipollenites, suggesting an Early Permian age (Late Sakmarian to Early Artinskian) to the sediments. It is further authenticated by the
occurrence of palynotaxa viz., Crucisaccites, Caheniasaccites, Indotriradites and Tiwariasporis. Upper Karharbari Formation has been demarcated for the first time in lithologically designated Barakar Formations in Ballarpur,
Durgapur, Majri and Hindustan Lalpeth Colliery while the sample 57/2 of bore hole CMWNM from Kawadi area may belong to the
Kamthi Formation on the basis of pinkish yellowish coarse grained to medium grained sandstone. An attempt has been made to
correlate these palynoassemblages with other Lower Gondwana basins of Early Permian affinity. 相似文献
18.
Occurrence of Cordaitales from lower Gondwana sediments of Ib-River Coalfield, Orissa, India: An Indian scenario 总被引：1，自引：0，他引：1
Kamal Jeet Singh Shreerup Goswami Shaila Chandra 《Journal of Asian Earth Sciences》2007,29(5-6):666-684
The Ib-River Coalfield in Orissa State is a part of Mahanadi Master Basin. Recent extensive investigations were conducted in this Coalfield to locate fossiliferous beds in the Lower Gondwana deposits and as a result a large cache of plant fossils were recovered from Lower Permian sediments (Barakar Formation) exposed in Jurabaga and Lajkura Collieries. The complete flora includes 23 genera representing nine orders viz., Lycopodiales, Equisetales, Sphenophyllales, Filicales, Cordaitales, Coniferales, Ginkgoales, Cycadales and Glossopteridales. Only the Cordaitales, represented by four genera i.e., Noeggerathiopsis, Cordaites, Euryphyllum and Kawizophyllum are discussed in this paper. Cordaitalean leaves are described for the first time from this coalfield; the remaining plant groups will be considered in a subsequent publication. Cordaitalean leaves attributable to Noeggerathiopsis hislopii, Noeggerathiopsis minor, Euryphyllum whittianum, Euryphyllum maithyi, Kawizophyllum dunpathriensis and Cordaites sp. constitute about 13.90% (111 specimens) of the total plant assemblage collected from this Coalfield. Of the cordaitaleans, N. hislopii is most abundant (47.75%; 53 specimens) followed by E. whittianum (40.54%; 45 specimens). A summary of the distribution of Cordaitales throughout the Indian Gondwana is also presented. Floristic composition varies stratigraphically at the two Barakar exposures (Lajkura and Jurabaga Collieries). Cordaitales are preserved only in the lowermost (4th) horizon (lower floral zone). Strata in these collieries have been assigned to the lower and upper Barakar Formation based on floristic content and an Early Permian (Artinskian) age is assigned. 相似文献
19.
本文作者在内蒙古乌兰浩特北沙巴尔吐一带开展1∶5万区调时,根据岩石组合、古生物特征、沉积环境等对出露于该地区扎格斯台一带的一套黑色砂板岩进行了重新厘定。重新厘定后的林西组为一套黑色板岩、粉砂岩夹细砂岩地层组合,具陆相沉积特征。该套地层在原1∶20万区调工作中被划归索伦组(P_(1~s)),原1∶25万区调又将其划归哲斯组(P_(2~(zs))),本次将上部陆相碎屑岩部分重新厘定为上二叠统林西组。该地层的重新厘定对本区寻找烃源岩有重要的指导意义。 相似文献
20.
贵州福泉-凯里地区含铝岩系分布广泛,但其产出时代一直存在争议。本文运用孢粉年代学的方法,对凯里-福泉地区铝土矿4条典型剖面采集6件孢粉样品,讨论铝土矿的形成时代。研究表明:本次发现的孢粉样品中"四方十字粉Crucisaccites quadratoides、布氏厚角孢Triquitrites bransonii和固定三肩孢Tantillus perstantus等是贵州早二叠世时期最常见的特征属种,因此将本区铝土矿成矿时代限定为早二叠世。与黔北务正道地区铝土矿对比,含铝岩系孢粉组合特征与黔北务正道地区含铝岩系中孢粉组合特征相似度高,含铝岩系应形成于早二叠世紫松期-隆林阶,与黔北务正道地区大竹园组铝土矿形成时代相当。 相似文献