【作者】 马小琴；

【导师】 王成文；

【作者基本信息】 吉林大学 ， 古生物学与地层学， 2010， 硕士

【摘要】 红水泉组是指大兴安岭地区早石炭世海相正常碎屑岩、灰岩,局部夹凝灰岩的地层。内蒙古呼伦贝尔盟伊敏地区发育红水泉组中段沉积,以泥质粉砂岩、粉砂质泥岩和泥岩为主,夹少量中—细砂岩。本次研究,课题组在伊敏地区红水泉组的泥岩中采集了大量的腕足动物化石,是首次发现,我们将其命名为“伊敏腕足动物群”。该腕足动物群以厚壳的石燕类,壳体较小的戟贝类和大型的长身贝类为主。本文依据居群理论,借鉴国际上最新的腕足动物分类方案,系统描述了早石炭世红水泉组的腕足动物化石10属10种,含2个新种,新种分别是伊敏等小长身贝Productellana yiminensis sp. nov.和伊敏线纹长身贝Linoproductus yiminensis sp. nov.。在此基础上建立了Linoproductus yiminensis—Fusella aschalensis组合,该组合的主要分子为:Neochonetes plicatiformis、Rugosochonetes hardrensis、Chonetes moelleri、Productellana yiminensis sp. nov.、Linoproductus yiminensis sp. nov.、Dictyoclostus crawfordswillensis、Fusella aschalensis、Finospirifer taotangensis、Torynifer pseudolineatus asiaticus、Stenoscisma sp.。依据Linoproductus yiminensis—Fusella aschalensis组合中腕足动物化石的分布时限,认为伊敏腕足动物群的时代应属于早石炭世杜内期,因此,将红水泉组中段的时代置于早石炭世杜内期。更多还原

【Abstract】 Hongshuiquan Formation is a suit of Early Carboniferous marine normal clastic, limestone, cliped tuff locally strata. In this study on Hongshuiquan Formation, we observed the section in a mountain at eastern of Heishantou township Hongshuiquan farm of Ergun Right Banner, Inner Mongolia. This section mainly represent the lower segment deposition of Hongshuiquan formation, comprising fine conglomerate, gritstone containing gravel, fine sandstone, siltstone, silty mudstone and shale compose a postitive cycle from coarse to fine, 472.45m thick. Upper section is incomplete, only amount to underpart of the upper section, representing a reverse cycle from coarse to fine, composed of shale, siltstone, fine sandstone, midian-coarse feldspar-quartz sandstone and fine conglomerate, more than 196.52m thick, containing some marine animal fossils brachiopoda and crinoid and so on. Upper and middle defects developed in 753.5 upland south of the observed section, comprising midian-fine sandstone, silty mudstone and carbonate rocks as bioclastic limestone, is a postitive cycle becoming thin upward, 283m, including large amount brachiopods, along to littoral neritic facies. Therefrom, these strata compose an entire Hongshuiquan Formation, and can be divided four lithologic members: underpart is sandy conglomerate; middle part is siltstone, mudstone; upper is sandy conglomerate and top is limestone.Early Carboniferous Hongshuiquan Formation in Yimin developed argillaceous siltstone, silty sandstone and mudstone, intercalated by little midian-fine sandstone, this strata is equal to middle part, siltstone, mudstone, in Hongshuiquan area. We collected a large number of brachiopod fossils in the silty mudstone of Yimin area, it is the first discovered, we named it as“Yimin brachiopod fauna”. The brachiopod fauna is charactered by Spiriferacea with thick shells, small Chonetoidea and large-scale Productoidea.Previous studies on the brachiopods of Hongshuiquan Formation is few, The earlest study is the identification of brachiopods from lower Carboniferous at the south of 753.5 upland in north of Dayinuogaigou byYu Jianzhang in 1956, those fossils preserved poorly, this study identified two genus, Spirifer sp. and Schellweinella sp., so he think the age of Hongshuiquan Formation belong to Devonian to Carboniferous. In 1957, when the 118 team worked in this area for 1:200000 scale regional geological survey, they found lots of fossils presserved well near 753.5 upland in north of Dayinuogaigou, mainly are brachiopods. These brachiopods were identified by a Russia paleontologist B.И.Устреский, including Camarotoechia cf. aschlariki Simorn, Spirifer aff. attenuatus Sow.,Pliticatifera kassini Nal.,Pictyoclostus sp.,Spirifer baiahi Nal.,Plicatifera aff. borukaeri Simorin,Spirifer cf. sibiricus Lebedev,Athyris aff. ahgelica Hall, he thought the strata containing these brachiopods along to lower Carboniferous Tournaisian, and considered Hongshuiquan Formation is the prime of Early Carboniferous.The paper has described 202 brachiopods from Hongshuiquan Formation systematicly, basing on population theory and referencing internationally latest brachiopod classification scheme, including 10 genera and 10 species, containing two new species. These species are: Neochonetes plicatiformis, Rugosochonetes hardrensis, Chonetes moelleri, Productellana yiminensis sp. nov., Plicatifera yiminensis sp. nov., Dictyoclostus crawfordswillensis, Stenoscisma sp., Fusella aschalensis Yang, Finospirifer taotangensis, Torynifer pseudolineatus asiaticus.We established Linoproductus yiminensis—Fusella aschalensis assemblage zone according to the composition character of Yimin brachiopod fauna. This assemblage mainly including elements such as Neochonetes plicatiformis、Rugosochonetes hardrensis、Chonetes moelleri、Productellana yiminensis sp. nov.、Linoproductus yiminensis sp. nov.、Dictyoclostus crawfordswillensis、Fusella aschalensis、Finospirifer taotangensis、Torynifer pseudolineatus asiaticus and so on. Symbiotic fossils including corals, blastoid, crinoids, etc. We established Linoproductus yiminensis-Fusella aschalensis assemblage zone. Because of this assemblage containing large number of Linoproductus yiminensis, a total of 120 samples, and incorporate the Early Carboniferous typical spirifer Fusella aschalensis,.In the Yimin brachiopod fauna, Neochonetes develop from Carboniferous to Permian wordwide; Rugosochonetes Sokolskaya produced during Carboniferous wordwide, the age of Fusella McCoy, Chonetes Fischer and Productellana Stainbrook is from Devonian to Early Carboniferous, mainly developed in Asia, Europe, North America and Russia. Dictyoclostus Muir-Wood distributed in Europe, Great Basin, Ireland, Belgium and Russia during Tournaisian-Visean of Early Carboniferous. Torynifer Hall developed in Asia and North America during Early Carboniferous, Torynifer pseudolineatus was founded in Kazakhstan, Altay and America during Early Carboniferous. Linoproductus cora, the type species of Linoproductus Chao, was found in Early Carboniferous of Caucasia. Finospirifer Yin produced in center of Hunan Provnince, China during Tournaisian of Early Carboniferous, Finospirifer taotangensis also is the typical spicies in Tournaisian. Rugosochonetes hardrensis distributed in South of Europe, Russia, Ural, Shinchi, Altay, Iran and Caucasia during Tournaisian. According to above analysis on the age of Yimin brachiopod fauna, the age of the fauna should be along to Tournaisian of Early Carboniferous. Therefore, the age of middle lower part of Hongshuiquan Formation is the Tournaisian.更多还原