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1.
Foraminiferal and conodont faunas at the Devonian–Carboniferous (D–C) boundary in the southern part of the Moravian Karst (Czech Republic) were studied in different facies of the basin slope. The joint presence of foraminifers and conodonts in calciturbidites along with a positive δ13C excursion of the Hangenberg anoxic event enabled the high‐resolution calibration of the late Famennian–early Tournaisian interval (Upper expansa–crenulata conodont zones). The conodont stratigraphic and biofacies succession reveals a strong correlation with other European areas. The Siphonodella sulcata morphotype (close to Group 1 sensu Kaiser and Corradini and “nov. gen. nov. sp. 1” sensu Tragelehn) enters prior to the Hangenberg Event, which resembles Upper and Uppermost Famennian conodont successions from Franconia, Bavaria and Morocco. The diversification of the early siphonodellids takes place after the Hangenberg Event and after the protognathodid radiation. In terms of foraminiferal biostratigraphy, the D–C boundary interval is characterized by the first appearance datum (FAD) of Tournayellina pseudobeata close below the D–C boundary followed by a sequence of Tournaisian bioevents, where apart from the last appearance datums (LADs) of quasiendothyrs, the FADs of the Neoseptaglomospiranella species and chernyshinellids play an important role in a similar manner as in Eastern Europe. The correlation of these bioevents elsewhere is often hindered by glacioeustatically‐driven unconformities and widespread occurrences of unfavourable facies for plurilocular foraminifers (Malevka beds and Bisphaera beds). Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

2.
西藏北喜马拉雅地层分区石炭纪仅发育杜内期一维宪期沉积,时间跨度约30Ma,含亚里组与纳兴组两个岩石地层单位。据吉隆沟地层的特征可识别出潮坪、三角洲及浅海陆棚等沉积相。由层序界面性质与地层结构特征划分为2个Ⅰ型层序、7个Ⅱ型层序、2个层序组,属1个超层序。多数层序仅由海侵体系域(TST)和高水位体系域(HST)两部分组成。  相似文献   

3.
甘肃靖远石炭系研究新进展   总被引:17,自引:6,他引:17  
<正> 甘肃靖远磁窑的石炭系出露完整,富含生物化石,李星学等(1974)作了较详细研究,奠定了本区石炭系层序的基础,首次建立了西北地区属于纳缪尔期的地层单元——靖远组。此后,不少地层和古生物工作者在对靖远磁窑石炭系作过调查,高联达对下石炭统作过孢粉研究(1980),王志浩、王成源(1983),史美良、赵治信(1985)对该区石炭系部分层  相似文献   

4.
The Middle Member of the Zorritas Formation in the Antofagasta region of northern Chile, yielded terrestrial and marine palynomorph assemblages which span the Devonian/Carboniferous boundary. The assemblages show a clear predominance of terrestrial palynomorphs with 70 miospore species, 18 marine phytoplankton species, two non-marine algae and one chitinozoan species, all coming from 15 productive levels. Palynomorphs are poorly preserved and most of them are reworked. Three palynological associations are recognized based on miospores. These are assigned to the Tournaisian–Visean, Tournaisian and probable latest Famennian. Age assignments are discussed in the frame of the spore zonal schemes established for Euramerica and western Gondwana. The stratigraphical distribution of spores allows the identification of the probable position of the Devonian/Carboniferous boundary within the Zorritas Formation. This system boundary is proposed for the first time in Palaeozoic sedimentary rocks of northern Chile. The presence of Gondwanan typical miospore species indicates affinities with this palaeocontinent even though the Tournaisian and Tournaisian–Visean miospore associations support the cosmopolitanism already suggested for the early Carboniferous flora. The significant number of reworked palynomorphs together with the sedimentological analysis of the studied sections, suggest that these deposits were severely impacted by the climatic change and major sea level fluctuations. Similar conditions were recorded in coeval western Gondwana basins.  相似文献   

5.
海南岛南好组剖析   总被引:9,自引:2,他引:7  
南好组是海南岛目前使用最广泛的地层单位之一 ,代表该岛整个下石炭统 ,但其选层型为下志留统而非岩关阶 ,保亭南好地区并不存在下石炭统 ;其副层型原本是青天峡组的层型。据此 ,南好组应予废弃。根据新近发现的吉维特期胞石 Eisenackitina castor、Grahanichitina pilosa、L agenochitina amottensis;法门期牙形刺 Palmatolepisgracilis gracilis、P.gracilis sigmoidalis、Polygnathus germanus;以石燕贝类为主的岩关期腕足动物群 Spirifercf.subgrandis、Fusella cf.fornacensis、Palaeochoristites sp.、Chonetipustula sp.、Marginatia sp.、Rhipidomellaspp.和牙形刺 Siphonodella isosticha- S.cooperi组合 ;以及滑石板期—达拉期牙形刺 Mesogondolella clarki组合 ,岛西北部地区的南好组废弃后可划分出 :中泥盆统吉维特阶 (?) (组名待建 )、上泥盆统法门阶昌江组、下石炭统岩关阶鸡实组 (新名 )、大塘阶青天峡组下段及三棱山组等不同地层单元  相似文献   

6.
A new stratigraphic nomenclature is proposed for the approximately 600 m thick, mainly clastic transitional sequence between the underlying Mempelam Limestone and overlying Kubang Pasu/Singa Formation in northwest Peninsular Malaysia. This sequence represents shallow marine deposits of the continental margin of the Sibumasu Terrane during the Middle Palaeozoic (Devonian–Carboniferous). It is separated into several formations. The Timah Tasoh Formation is an approximately 76 m sequence consisting of 40 m of laminated tentaculitid shales at the base, containing Monograptus yukonensis Jackson and Lenz and Nowakia (Turkestanella) acuaria Alberti, giving an Early Devonian (Pragian–Emsian) age, and about 36 m of rhythmically interbedded, light coloured argillo-arenites. The Chepor Formation is about 90 m thick and consists mainly of thick red mudstone interbedded with sandstone beds, of Middle to Late Devonian age. A new limestone unit is recognized and named the Sanai Limestone, which contains conodonts of Famennian age. The Binjal Formation consists of red and white mudstone interbedded with sandstone beds showing Bouma sequences. The Telaga Jatoh Formation is 9 m thick and consists mainly of radiolarian chert. The Wang Kelian Formation is composed of thick red mudstone beds interbedded with silty sandstone, and contain fossils indicative of an Early Carboniferous (Visean) age. The succession was deposited on the outer shelf, with depositional environments vertically fluctuating from prodelta to basinal marine. The Devonian–Carboniferous boundary is exposed at Hutan Aji and Kampung Guar Jentik, and indicates a major regressive event during the latest Devonian.  相似文献   

7.
The stratigraphy of the Devonian to Permian succession in Northwest Peninsular Malaysia is revised. The Timah Tasoh Formation consists of black mudstone containing graptolites and tentaculitids indicating a Pragian or earliest Emsian age. The Sanai Limestone overlies the Timah Tasoh Formation at Sanai Hill B and contains conodonts indicating a Late Devonian (Frasnian to possibly early Famennian) age. In other places, Late Tournaisian chert of the Telaga Jatoh Formation overlies the Timah Tasoh Formation. The overlying Kubang Pasu Formation is predominantly composed of mudstone and sandstone, and can be divided into 3 subunits, from oldest to youngest: (1) Chepor Member; (2) Undifferentiated Kubang Pasu Formation; (3) Uppermost Kubang Pasu Formation. The ammonoid Praedaraelites tuntungensis sp. nov. is reported and described from the Chepor Member of Bukit Tuntung, Pauh. The genus indicates a Late Viséan age for part of the subunit. Dropstones and diamictites from the Chepor Member indicate a glacial marine depositional environment. The Carbo-Permian, undifferentiated Kubang Pasu Formation consists of similar interbedded mudstone and sandstone. The uppermost Kubang Pasu Formation of Kungurian age consists of coarsening upward cycles of clastics, representing a shallow marine, wave- and storm-influenced shoreline. The Permian Chuping Limestone also represents shallow marine, wave- and storm-influenced deposits. A Mid-Palaeozoic Unconformity separating Early–Late Devonian rocks from overlying Late Devonian–Carboniferous deposits probably marks initiation of rifting on Sibumasu, which eventually led to the separation of Sibumasu from Australian Gondwana during the late Sakmarian (Early Permian).  相似文献   

8.
牙形石在以碳酸盐岩为主的华北奥陶系划分对比中占有举足轻重的地位。针对华北奥陶纪牙形石的研究已持续近半个世纪,总体上可以分为两个阶段:第一阶段自20世纪70年代到21世纪初,第二阶段为最近10年(2010—2020)。第一阶段以建立牙形石生物地层序列为目标,主要为解决石油勘探过程中地层时代的确定和地层对比的需求;第二阶段的研究以修订化石带为主,目的是与国际地层研究接轨。近年来在华北板块西北缘的工作显示,该区奥陶纪牙形石在纵向上具有显著的生态变化,可分为达瑞威尔期中期、达瑞威尔期晚期—桑比期中期、桑比期晚期—凯迪期中期3个时段。第一时段以介于北美中大陆区和北大西洋区之间的热带台地边缘型牙形石为特征;第二时段以北大西洋型为主混有少量亚澳型牙形石为特征;第三时段以亚澳型和北美中大陆型牙形石混生为特征。在华北西北缘尽可能使用广布性标准牙形石属种进行化石带厘定,共识别牙形石带12个,自下而上分别是达瑞威尔期Histiodella cf. holodentata间隔带、Histiodella kristinae谱系带、Histiodella bellburnensis延限带、Dzikodus tablepointensis间隔带、Eoplacognathus suecicus间隔带、Pygodus serra间隔带和Pygodus anserinus(早期型)间隔亚带,桑比期Pygodus anserinus(晚期型)间隔亚带和Belodina compressa间隔带,凯迪期Belodina confluens间隔带、Yaoxianognathus neimengguensis间隔带和Yaoxianognathus yaoxianensis间隔带。由于部分化石带与国际同名带的对比还存在一些矛盾,尚需今后进一步解决。  相似文献   

9.
Carboniferous deep‐water marine strata have been insufficiently studied in western Junggar, NW China where the deep‐water facies successions have long been disputed in terms of age constraints, sequence and palaeoenvironmental reconstruction. This paper introduces some views in the light of new materials obtained from this region in recent years. The presence of the Visean plant fossils from the upper Ta'erbahatai Formation in the Tarbgatay Mountains indicates that the formation can be extended to the Early Carboniferous epoch in age. This unit also displays obvious diachroneity, which is of Late Devonian to Early Tournaisian age in the Saur Mountains and Late Devonian to Visean age in the Tarbgatay Mountains. The Xibeikulasi, Baogutu and Tailegula formations are widely distributed in northwestern Karamay areas. The scouring structures and graded bedding near the boundaries between the three formations confirm the stratal sequence that they were originally assigned, namely the Xibeikulasi, Baogutu and Tailegula formations in ascending order. The ‘fossil chaos’ of the three formations is due to mistaking fossils of other stratigraphic units for fossils of these three formations. After revision, only the Early Carboniferous fossils are considered reliable, and combined with the newly found plant fossils, the Xibeikulasi, Baogutu and Tailegula formations are re‐assigned to the early Visean, late Visean, and latest Visean to Serpukhovian ages, respectively. An extension of the lower Hala'alate Formation was recognized in the southwestern Hala'alate Mountains. The presence of the latest Early Carboniferous brachiopods constrains the Hala'alate Formation as late Serpukhovian to Bashkirian in age, bearing the mid‐Carboniferous boundary. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

10.
石炭纪—二叠纪旋回层是由晚古生代冈瓦纳冰川的冰期与间冰期的交替而造成的海进—海退循环沉积的层序,出现在全球尤其是北半球的很多地区。根据岩石微相和沉积构造特征,安徽巢湖凤凰山石炭系和州组,可识别出5个海进—海退沉积序列;根据和州组中有孔虫的分布特征,自下而上可分为5个有孔虫带,确定其地质年代是从维宪期晚期到巴什基尔期早期。这5个海进—海退沉积旋回,与华南其他地区和欧美地区的同时代地层中出现的大的海进—海退事件基本一致。  相似文献   

11.
In an attempt to elucidate their ages, the often incomplete and poorly known early Permian marine faunas and sequences of India, Tibet, Pakistan, Afghanistan, Iran and Oman are compared with those of the Perth, Carnarvon and Canning Basins of Western Australia, where faunas are documented and in sequence, and stratigraphic relationships between units are clear. This comparison indicates that the faunas discussed are Latest Asselian or younger in age, and that most of the underlying glacial beds are probably Early Permian (Asselian) in age. By implication, the Permo‐Carboniferous boundary for Gondwana is considered to lie at or near the base of Unit II/Stage 2 and equivalent palynomorph zones throughout Gondwana.  相似文献   

12.
龙木错-双湖-澜沧江板块缝合带与石炭二叠纪冈瓦纳北界   总被引:29,自引:0,他引:29  
1982—1983年间,作者在改则幅和日土幅1:100万区域地质调查中,发现在黑头山—冈玛错—角木日—双湖一带,存在严重解体的蛇绿岩带。后经进一步工作,获悉该带明显地控制了冈瓦纳相和特提斯相石炭、二叠系的分布,并有高压变质带的岩石出露。因此,该带为一条北西西—南东东向的板块缝合带,它应是目前国内外地质界都在寻找的冈瓦纳大陆的北界。  相似文献   

13.
云南保山地区的下石炭统   总被引:4,自引:1,他引:4  
王向东  朱夔玉 《地层学杂志》1993,17(4):241-255,T002
<正> 云南保山地区下石炭统及其生物群曾引起许多学者的兴趣(Reed l927;王鸿桢,1945;段丽兰,1973,1985;宋学良,1982;金玉玕、方润森,1983;杨宗仁,1983;陈重泰,1984;陈根保,1984;金苏华,1992),其主要原因在于丰富而特殊的生物类群,悬而未决的地层问题以及独特的生物地理位置。本文以4条剖面(图1)为基础,依据多门类的生物化石对诸如本区杜内/维宪阶界线、Siphonophyllia-Keyserlingophyllum(Humboldtia)动物群的时代、冷水(凉水)珊瑚动物群、岩石地层单位等问题进行讨论。  相似文献   

14.
The Malay Peninsula is characterised by three north–south belts, the Western, Central, and Eastern belts based on distinct differences in stratigraphy, structure, magmatism, geophysical signatures and geological evolution. The Western Belt forms part of the Sibumasu Terrane, derived from the NW Australian Gondwana margin in the late Early Permian. The Central and Eastern Belts represent the Sukhothai Arc constructed in the Late Carboniferous–Early Permian on the margin of the Indochina Block (derived from the Gondwana margin in the Early Devonian). This arc was then separated from Indochina by back-arc spreading in the Permian. The Bentong-Raub suture zone forms the boundary between the Sibumasu Terrane (Western Belt) and Sukhothai Arc (Central and Eastern Belts) and preserves remnants of the Devonian–Permian main Palaeo-Tethys ocean basin destroyed by subduction beneath the Indochina Block/Sukhothai Arc, which produced the Permian–Triassic andesitic volcanism and I-Type granitoids observed in the Central and Eastern Belts of the Malay Peninsula. The collision between Sibumasu and the Sukhothai Arc began in Early Triassic times and was completed by the Late Triassic. Triassic cherts, turbidites and conglomerates of the Semanggol “Formation” were deposited in a fore-deep basin constructed on the leading edge of Sibumasu and the uplifted accretionary complex. Collisional crustal thickening, coupled with slab break off and rising hot asthenosphere produced the Main Range Late Triassic-earliest Jurassic S-Type granitoids that intrude the Western Belt and Bentong-Raub suture zone. The Sukhothai back-arc basin opened in the Early Permian and collapsed and closed in the Middle–Late Triassic. Marine sedimentation ceased in the Late Triassic in the Malay Peninsula due to tectonic and isostatic uplift, and Jurassic–Cretaceous continental red beds form a cover sequence. A significant Late Cretaceous tectono-thermal event affected the Peninsula with major faulting, granitoid intrusion and re-setting of palaeomagnetic signatures.  相似文献   

15.
石炭纪年代地层学研究概况   总被引:20,自引:6,他引:14  
国际石炭系分会尝试性地将石炭系分成两部分 ,下石炭亚系或 Mississipian及上石炭亚系或 Pennsylvani-an,前者包括 3个统 :Tournaisian,Visean,Serpukhovian;后者包括 4个统 :Bashkirian,Moscovian,Kasimovian以及Gzhelian。由于全球对比的需要 ,西欧和北美的统级年代单位作为辅助性序列也被置于综合年代地层表中。石炭系底界、中间界线及顶界的 GSSP已经分别确立在法国的 L aserre剖面 ,美国的 Arrow Canyon剖面 ,哈萨克斯坦的Aidaralash Creek剖面。据西欧及澳大利亚的同位素年龄数据 ,石炭纪的时间跨度为 5 3 Ma。中国的石炭系划分成丰宁亚系和壶天亚系 ,前者包括岩关统和大塘统以及汤粑沟阶 ,旧司阶 ,上司阶和德坞阶 ;后者包括威宁统和马平统以及罗苏阶 ,滑石板阶 ,达拉阶和小独山阶。  相似文献   

16.
广州地区晚泥盆世至早石炭世地层及植物组合   总被引:2,自引:0,他引:2  
金建华  吴起俊 《地层学杂志》2001,25(3):166-173,206
广州地区晚泥盆世至早石炭世地层发育良好 ,出露地层为上泥盆统金钱岭组、沙水岗组以及下石炭统龙江组、石磴子组、测水组和梓门桥组 ,含有非常丰富的动植物化石 ,其中 ,广州市西北郊出露有陆相晚泥盆世至早石炭世地层的连续剖面 ,是研究陆相泥盆系与石炭系界线的理想剖面。含植物化石的陆相地层沙水岗组、龙江组和测水组中的植物化石可划分为 4个组合 ,自下而上为 :1) L epidodendropsis hirmeri- Sublepidodendron mirabile- H ama-tophyton verticillatum组合 ,代表沉积为沙水岗组 ,时代为晚泥盆世晚期 ;  2 ) Sublepidodendron mirabile-Rhodeopteridium cf. hsianghsiangense组合 ,代表沉积为龙江组 ,时代为早石炭世杜内期 ;  3) Cardiopteridiumspetsbergense- Triphyllopteris collombiana- Adiantites gothanii组合 ,代表沉积为测水组下段 ,时代为早石炭世维宪早期 ;  4) Archaeocalamites scrobiculatus- Cardiopteridium spetsbergense- Paripteris gigantea组合 ,代表沉积为测水组上段 ,时代为早石炭世维宪晚期  相似文献   

17.
The paper describes a Serpukhovian Stage section, exposed along the Ural River near the village of Verkhnyaya Kardailovka (Bashkortostan). The section is uniquely complete and is proposed as a GSSP candidate for the base of the Serpukhovian. The Upper Visean and Serpukhovian beds are represented by relatively deep facies, which contain ammonoids, conodonts, ostracods, foraminifers, and other fossils. The section is described bed-by-bed and subdivided into zones based on four faunal groups. The lower boundary of the Serpukhovian is placed at the base of the Lochriea ziegleri conodont zone. The stratigraphic units are correlated with synchronous beds of the East European Platform, the Donets Basin, Western Europe, Central Asia, and North America.  相似文献   

18.
It is well known that western Myanmar is underlain by a continental fragment, the West Burma Block, but there are arguments about its origin and the time of its arrival in SE Asia. This study presents the first petrological, XRD diffraction, heavy mineral and detrital zircon U-Pb age data from turbidite sandstones in the Chin Hills that were deposited on West Burma crust in the Triassic. These sandstones contain detritus derived from areas surrounding West Burma and thus help resolve arguments about its location in the Palaeozoic and Mesozoic. West Burma, Sibumasu and Western Australia have similar populations of Archean zircons derived from Western Australian cratons. Until the Devonian all formed part of the Gondwana supercontinent. The abundance of Archean zircons decreases from Western Australia to West Burma and then to Sibumasu. This is consistent with their relative positions in the Gondwana margin, with Sibumasu furthest outboard from Western Australia. Differences in zircon populations indicate that Indochina was not close to West Burma or Sibumasu in Gondwana. West Burma contains abundant Permian and Triassic zircons. These are unknown in Western Australia and different from those of the Carnarvon Basin; they were probably derived from SE Asian tin belt granitoids. Cr spinel is present in most West Burma sandstones; it is common in SE Asia but rare in Western Australia. These new data show that West Burma was part of SE Asia before the Mesozoic and support suggestions that the Argo block that rifted in the Jurassic is not West Burma.  相似文献   

19.
<正> 下扬子地区早石炭世地层发育,研究历史早,工作精度高。笔者在前人的基础上,对区内岩石地层剖面和沉积构造作了详细观察,分析了沉积物来源和古生物特征,建立了四个海进—海退的沉积序列,讨论其时代。把本区划分为三个沉积相带:北带——滨海、宝应到巢县一带;中带——南京、镇江、溧阳至泾县一带;南带——江阴、宜兴、湖州、宣城沿长江至鄂东南(图1)。  相似文献   

20.
首次在准噶尔西北部塔尔巴哈台组上部发现了早石炭世维宪期植物化石 Archaeocalamites scrobiculatus,Sublepidodendron grabaui,S. mirabile,S. cf. mirabile,Sublepidodendron sp., Lepidodendropsis sp., Mesocalamites sp., Sigillaria sp., Rhodiopteridium?sp.,Knorria sp.,证实了该组的时代可延续到早石炭世。根据研究区塔尔巴哈台组和上覆黑山头组的生物组合面貌及二者的接触关系,论证了塔尔巴哈台组顶部和黑山头组在准噶尔西北部具有明显的穿时性,前者从杜内期延续到维宪期,后者从杜内期延续到谢尔普霍夫期。与植物化石共同保存的深水相遗迹化石指示了塔尔巴哈台地区在早石炭世早中期为半深海-深海沉积环境,不同于东部吉木乃地区同期的滨浅海沉积环境,说明准噶尔西北部在早石炭世存在着不同的沉积体系。北疆地区早石炭世广泛的海侵活动以及额尔齐斯-斋桑洋向南侧哈萨克斯坦板块俯冲是造成这种沉积差异的主控因素,同时也造成了塔尔巴哈台组和黑山头组在区域上具穿时性。  相似文献   

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