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华南晚三叠世Dictyophyllum-Clathropteris植物群可划分三个组合:1.Lepidopteris otlonis-Hubeiophyllum cuneifolium组合,时代为卡尼期的中-晚期;2.Anthrophyopsis crassinervis-Riret-icopteris microphylla组合,时代为卡尼期的晚期-诺尼期的早期;3.Goeppertella kwangyuanensis-Selaginellites yunnanensis组合,时代为诺尼期。鄂西荆当、秭归盆地的洞竹园组和香溪组(狭义).底部有一层底砾岩或含砾砂岩,层位稳定.是三叠-侏罗系分界岩性标志。同时表明该区晚三叠世末期,地壳上升,改变了原来的环境,造成晚三叠世的三个植物组合标准分子和大部分常见分子绝灭.晚三叠世双亮类标准属种也逃脱不了这次毁灭性的灾难.而代表侏罗纪的金鸡组、武昌组、桐竹园组及香溪组(狭义)含的植物、菊石及双壳类则以崭新的面貌出现。据此,笔者认为华南晚三叠世末期,发生了一次重大的生物地质事件。文中还对Dictyophyllum-Clathropteris植物群的含义提出了不同的看法。 相似文献
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在新疆天山南北两侧的吉木萨尔大龙口剖面和吐鲁番桃树园剖面克拉玛依组中发现了植物化石17属28种。首次在
克拉玛依组下部发现了Pleuromeiasp.和Annalepiscf.zeilleri。同时在上部发现了大量晚三叠世分子。克拉玛依组植物面貌属
于Danaeopsis-Bernoullia 植物群。通过对克拉玛依组植物群组成、特征及生境的分析,并根据植物化石的组成及分布规律的研
究,探讨了克拉玛依组的时代,认为克拉玛依组下部为中三叠世地层,上部为晚三叠世地层,不宜将上部单独建组。 相似文献
克拉玛依组下部发现了Pleuromeiasp.和Annalepiscf.zeilleri。同时在上部发现了大量晚三叠世分子。克拉玛依组植物面貌属
于Danaeopsis-Bernoullia 植物群。通过对克拉玛依组植物群组成、特征及生境的分析,并根据植物化石的组成及分布规律的研
究,探讨了克拉玛依组的时代,认为克拉玛依组下部为中三叠世地层,上部为晚三叠世地层,不宜将上部单独建组。 相似文献
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《地球科学与环境学报》2015,(4)
四川盆地上二叠统—下三叠统碳酸盐岩地层中富集天然气,天然气藏的分布受优质烃源岩和礁滩相储层的控制。为了揭示四川盆地沉积演化背景下天然气的富集规律及预测成藏有利区,对晚二叠世—早三叠世扬子古板块地质构造背景进行分析,讨论地质构造背景控制下四川盆地晚二叠世—早三叠世沉积演化特征;根据不同时期构造和沉积演化特征确定优质烃源岩和储层的发育机理和分布范围;结合天然气成藏模式的认识,确定天然气成藏有利区。结果表明:四川盆地晚二叠世—早三叠世海湾及其后陆棚的发育演化控制了该区龙潭组主力烃源岩与长兴组—飞仙关组礁滩相储层的发育分布,形成了下生上储的有利配置关系;川东北地区长兴组—飞仙关组台地边缘礁滩相储层邻近龙潭组海湾相优质烃源岩的区域为天然气成藏最有利区。总之,四川盆地晚二叠世—早三叠世沉积演化特征控制了海相优质烃源岩和储层的发育分布,决定了天然气的富集与分布。 相似文献
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文章对桂林三叠世时的古地理及古气候条件、晚三叠世内陆湖盆的发育及堆积物和残留特征进行了描述，探讨了中晚三叠世桂林热带岩溶发育的程度。认为中晚三叠世是桂林热带岩溶极为强烈发育时期，也是岩溶洞穴强烈发育的一个时期，从此奠定了桂林热带岩溶地貌轮廓雏形。迄后的地质历史中，其热带岩溶基本上是在此基础上的继承发育。 相似文献
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通过对宁阳煤田茅庄井田煤系地层综合分析,揭示了茅庄井田的煤层岩性特征和沉积环境。研究结果表明:该井田主要含煤地层为早二叠世山西组和晚石炭世—早二叠世太原组,总厚度约220 m。可采或局部可采者4层,即3上煤层,3下煤层,16煤层、17煤层,平均总厚度为9.52 m。本井田内3上煤层、3下煤层为主采煤层。含煤地层为石炭—二叠纪月门沟群,其中山西组是该区最重要的含煤地层。沉积环境为从海相沉积为主到以陆相沉积为主的转变过渡时期,岩石地层反映了典型的海陆交互相的沉积特征;在海陆交互期海退三角洲平原上供应了大量的泥炭沼泽,为茅庄井田煤层提供了物质基础。其中太原组为典型的海陆交互相沉积,沉积相环境稳定,变化小,标志层及煤层层位清楚、稳定,煤层沉积层序规律性强,是区域地层对比的稳定层位。 相似文献
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本文将广西大容山—十万大山花岗岩岩基划分为4个超单元和22个单元,并根据各单元间接触关系和40个同位素年龄数据,建立了本区花岗岩的地质年代表,即分别形成于早二叠世、晚二叠世、早三叠世和中三叠世等4个地质时代。 相似文献
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本文研究了青海省中奥陶世至早三叠世的牙形剌化石,依据其产出层位自下而上可划分为六个组合Ⅰ中奥陶世 Pygodus anserinus 组合;Ⅱ中—晚泥盆世 Icriodus expansus 组合;Ⅲ早石炭世 Gnathodus bilineatus 组合;Ⅳ晚石炭世 Streptognathodus elegantulus 组合;Ⅴ早二叠世 Sweetognathus whitei 组合;Ⅵ早三叠世 Neospathodus homeri 组合。此牙形剌组合,既丰富了我省古生代及三叠纪的古生物资料,又为相应地层的划分、对比提供了重要依据。 相似文献
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张启武 《国土资源导刊(湖南)》2006,(Z1)
湘中主要赋存有下石炭统测水组、上二叠统龙潭组、上三叠统安源组和下侏罗统造上组等煤系。湘中煤层气含量主要是受煤级、煤层埋深、构造运动、围岩、水文地质条件因素的影响。 相似文献
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红阳煤田含煤地层太原组与山西组,是一套典型的“海陆交互相”沉积。依据剖面上沉积相序列变化特点,可划分为14个沉积旋回,每个沉积旋回均含有一层煤。有二种聚煤环境:一是海水退出潮坪后形成的泥炭沼泽聚积的煤层;二是扇三角洲平原形成的泥炭沼泽聚积的煤层。 相似文献
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西藏冈底斯B型山链南缘松多群的构成及其变质变形特征 总被引：2，自引：0，他引：2
松多群是冈底斯B型山链变质基底的组成部分之一 ,并于晚三叠世—晚第三纪雅江缝合带俯冲超碰撞阶段演化为该B型山链活化根带逆冲推覆超岩片 ,系冈瓦纳大陆北缘于震旦—寒武纪小洋盆及陆缘火山沉积的产物。松多群岔萨岗组、马布库组、雷龙库组及罗马岭超镁铁质岩带 ,彼此间均为构造接触 ,实为一套构造岩石组合体 ,由时代相近而来源、性质不同的地质体构成 ,并经历了低绿片岩相—低角闪岩相变质作用和 4期主要构造变形。岔萨岗组主体为变质基性火山岩 ,化学成分相当TMORB ;马布库组、雷龙库组片岩、石英岩相当于被动陆缘泥砂质复理石建造及石英质复理石建造。罗马岭超镁铁质岩经综合分析判别则形成于伸展裂陷小洋盆构造环境。因而得出松多群为一较完整有限小洋盆火山沉积产物的结论。 相似文献
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本文是在前人的煤岩、煤质测试成果与资料基础上进行初步综合研究,试对广西早石炭世寺门时煤质特征及其煤的用途进行探讨。根据煤岩学和煤盆地相分析认为:广西寺门时煤主要聚集于煤盆地的滨岸碎相带和潮坪—沼泽相带中;煤种以无烟煤为主,少量的贫煤与瘦煤,无烟煤仅硫量稍高其余各项指标符合优质煤的标准,可用于合成氨及动力燃料。 相似文献
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本文介绍了陕南西乡峡口地区上二叠统地层问题,着重研究了其在大巴山西段的发育规律。据其组合类型,可划分出台地相区、台坡相区和台沟相区等三个沉积相区。对长兴期的大隆组与吴家坪组的相变问题,本文则进一步提出:在横向上,它们是同期异相;在纵向上,它们在过渡的台坡相区内表现为大隆组在上,并随着背离台地相区距离的增加,大隆组的厚度比增大。根据(竹蜒)和有孔虫的产出,对晚二叠世地层提出了分带意见,并依据岩性、岩相、古生物以及沉积间断现象存在与否,指出了二叠系与三叠系在台地相区是平行不整合,在台坡或台沟相区是整合的结论。 相似文献
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豫西济源—义马盆地早中生代地层谭庄组中上段（Ｔ３）和鞍腰组（Ｊ１）是典型的湖泊体系沉积。谭庄组沉积期湖泊相对较浅,受气候控制。由于受季风环流的影响,推测晚三叠世晚期的季节性更强。在三叠纪末—早侏罗世,发生了走滑构造作用。鞍腰组沉积期为走滑引张体制下的湖泊,水体较深,反映了构造沉降的开始。在随后的走滑挤压阶段,该湖泊为三角洲和河流相碎屑沉积物充填。 相似文献
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吉南候家屯组与辽东小东沟组在辽东北部连成一体，以往地层划分和对比上的分歧，皆由王钰等定义小东沟组含有熔岩——“为小岭期火山喷发初的火山活动产物”所致。小东沟组、候家屯组为独立于辽东小岭组，吉南果松组火山岩之外的地层体，为干旱炎热气候条件下的河湖相沉积。辽东梨树沟组建立时未明确定义，建组剖面仅共分二层，为凝灰岩、凝灰质砂岩夹砂页岩，多数研究者将其理解为小岭期火山喷发的尾声产物，无疑是正确的，但近年已人为地演义为“远火山相和湖相”（沉积），并与辽西九佛堂（沙海）组对比，已失去岩石地层单位组的客观性、物质性及组内岩性、岩相的一致性。现据“组应概分，不易细分”等有关原则，建议废弃梨树沟组名称，将与小岭组有成因联系的远火山相产物（包括夹层）划归小岭组，其上部确与小岭期火山喷发无关的河湖（沼）相沉积归于聂尔库组 相似文献
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Guimei WAN Liangjie TANG Wenzheng JIN . Basin Reservoir Research Centre China University of Petroleum Beijing China. Key Laboratory for Hydrocarbon Accumulation Mechanism of Ministry of Education China University of Petroleum Ministry of Education Beijing China 《东北亚地学研究》2007,10(2):156-165
Compared Kuqa foreland basin with Persian Gulf Basin in development of salt layers, salt tectonics, and the relation between salt tectonics and hydrocarbon, it is concluded that the salt diapirs are relative to hydrocarbon. Searching salt diapirs and related traps in Kuqa foreland basin is important. The forming mechanism of salt tectonic in Kuqa foreland basin is different from that of Hormuz Series, but similar to that of Lower Fars Series/Gachsaran Formation. Inspired by the role of salt tectonics of Lower Fars Series/Gachsaran Formation in hydrocarbon accumulation, the authors considered that the exploration below salt layer should be enforced, and the traps below salt layer in the southern part of the Kuqa foreland basin would be found where salt layer is thicker. On the contrary, the traps should be found both above and below the salt layer in front of the northern mountain where salt layer is thin. The Triassic and Jurassic source rocks are rich in this area with great exploration prospective. 相似文献
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Compared Kuqa foreland basin with Persian Gulf Basin in development of salt layers, salt tectonics, and the relation between salt tectonics and hydrocarbon, it is concluded that the salt diapirs are relative to hydrocarbon. Searching salt diapirs and related traps in Kuqa foreland basin is important. The forming mechanism of salt tectonic in Kuqa foreland basin is different from that of Hormuz Series, but similar to that of Lower Fars Series/Gachsaran Formation. Inspired by the role of salt tectonics of Lower Fars Series/Gachsaran Formation in hydrocarbon accumulation, the authors considered that the exploration below salt layer should be enforced, and the traps below salt layer in the southern part of the Kuqa foreland basin would be found where salt layer is thicker. On the contrary, the traps should be found both above and below the salt layer in front of the northern mountain where salt layer is thin. The Triassic and Jurassic source rocks are rich in this area with great exploration prospective. 相似文献
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ShigeyukiSuzuki AbdulR.Ashraf HakuyuOkada 《东北亚地学研究》2004,7(2):149-155
Sedimentary facies of the Tsagayan Formation is distributed in the eastern Zeya-Bureya Basin has been analyzed. The formation is of the Maastrichtian to Danian in age and characterized by the cyclicity of the fining-upwards successions. Analysis of environmental changes during the K/T boundary is the focus of this study. Five facies have been identified: Facies A, thick and laterally extensive coarse-grained to medium-gained sandstone units, interpreted as channelfill deposits; Facies B, parallel-laminated to massive mudstone units interpreted as interchannel lakes and flood plain deposits; Facies C, sheet-like medium-grained to fine-grained sandstones interpreted as crevasse splay deposits; Facies D, coal to coaly mudstone beds interpreted as deposits of peatlands; Facies E, very poorly sorted sandy mudstone beds interpreted as debris flow deposits. Fluvial environments with the low-relief fiat topography was inferred. A channel transported large volumes of clasts, and a flood basin with interchannel lakes and peatlands was deciphered. Any distinct change of sedimentary environments has not been identified throughout the Tsagayan Formation (including the K/T boundary). However, two beds of debris flow deposits were identified. The one occurs at the uppermost part of the lower Tsagayan Subformation and contains dinosaur fossils. The other is intercalated in the upper Tsagayan Subformation. 相似文献
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Sedimentary facies of the Tsagayan Formation is distributed in the eastern Zeya-Bureya Basin has been analyzed. The formation is of the Maastrichtian to Danian in age and characterized by the cyclicity of the fining-upwards successions. Analysis of environmental changes during the K/T boundary is the focus of this study. Five facies have been identified: Facies A, thick and laterally extensive coarse-grained to medium-grained sandstone units, interpreted as channelfill deposits; Facies B, parallel-laminated to massive mudstone units interpreted as interchannel lakes and flood plain deposits; Facies C, sheet-like medium-grained to fine-grained sandstones interpreted as crevasse splay deposits;Facies D, coal to coaly mudstone beds interpreted as deposits ofpeatlands; Facies E, very poorly sorted sandy mudstone beds interpreted as debris flow deposits. Fluvial environments with the low-relief flat topography was inferred. A channel transported large volumes of clasts, and a flood basin with interchannel lakes and peatlands was deciphered. Any distinct change of sedimentary environments has not been identified throughout the Tsagayan Formation (including the K/T boundary). However, two beds of debris flow deposits were identified. The one occurs at the uppermost part of the lower Tsagayan Subformation and contains dinosaur fossils. The other is intercalated in the upper Tsagayan Subformation. 相似文献