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1.
1 IntroductionThe Wupata'erkan Group, also called Wupata'erkanFormation (Wang et al., 1990), in the western SouthTianshan, China (Fig. 1), mainly comprises gray and darkgray fine-grained clastic rocks, interlayered with medium-acidic volcanic rocks (andesite and quartz porphyry),carbonates, cherts and variegated tuffaceousconglomerates. The chert in the formation was firstly foundin our field trip along sections of the Qiqi'erjianakesu Riverand Kekebiele Daban. Deformation of the group is…  相似文献   

2.
1 IntroductionThe Wupata'erkan Group, also called Wupata'erkanFormation (Wang et al., 1990), in the western SouthTianshan, China (Fig. 1), mainly comprises gray and darkgray fine-grained clastic rocks, interlayered with medium-acidic volcanic rocks (andesite and quartz porphyry),carbonates, cherts and variegated tuffaceousconglomerates. The chert in the formation was firstly foundin our field trip along sections of the Qiqi'erjianakesu Riverand Kekebiele Daban. Deformation of the group is…  相似文献   

3.
通常人们一直认为阿木岗(戈木日)群是所谓“羌塘地块”的前寒武纪或前泥盆纪基底,曾发现古生物化石的“中泥盆统”查桑群和“下二叠统”鲁谷组等是其上的晚古生代盖层沉积。本次工作在阿木岗群和鲁谷组中分别发现中-晚三叠世放射虫化石组合;在查桑群中发现二叠纪中-晚期放射虫化石组合。结合野外实际考察和前人研究成果,本文就有关问题作了讨论。  相似文献   

4.
新疆昆仑山中泥盆世四射珊瑚   总被引:1,自引:0,他引:1  
新疆昆仑山中泥盆世四射珊瑚较为丰富.本文只描述Atelophyllum sp.,Cyatho-phyllum sp.,Disphylloides philomena,Disphyllum carinatum(sp.nov.),Xystriphyllumkunlunense(sp.nov.)等5属3种,其中有二个新种.其共生的有床板珊瑚、层孔虫、及腕足类等.它们均产于中泥盆统布拉克巴什群.可与新疆北部、内蒙、甘肃、陕西、贵州等地的同期地层对比.  相似文献   

5.
A new genus, Hemibashkirella (type species: H. bifurcata, n. sp.), is erected for a phylloporinid bryozoan found in the Middle Devonian (Eifelian stage) of Armenia. Phylloporinids have not hitherto been reported from the Devonian. The new genus appears to be a link between Chasmatoporella Nekhoroshev of the Ordovician and Silurian and Bashkirella Nikiforova of the Carboniferous and Permian. Hemibashkirella differs from Chasmatoporella in having more than two rows of zooecia on the branches and in lacking a median carina. It differs from Bashkirella in having a more sharply defined linear axis and a simpler capillary system.—H. Duncan.  相似文献   

6.
中国南方泥盆系的颗石藻   总被引:2,自引:1,他引:2       下载免费PDF全文
侯奎  陈延成 《地质科学》1991,(3):239-245
本文鉴定和描述了中国南方泥盆系的颗石藻化石,计有两个新属,八个新种和一个未定种。其中中华甲球藻属(新属)(Sinothoracosphaera gen.nov.)包括盘桃中华甲球藻(新种)(S.placenta sp.nov.)和异孔中华甲球藻(新种)(S.heteromorphicpororata sp.nov.);始驳船球石属(新属)(Eopontosphaera gen.nov.)只一个新种,即背篓形始驳船石(新种)(E.basketa sp.nov.)其它五个新属是瘤刺篮石(新种)(Scyphosphaera verruca-cras-sispina sp.nov)、小卷螺海石颗石藻(新种)(Helicopontosphaera snaila sp.nov.)、口盖无缘帽形石(新种)(Calyptrolithus operculum sp.nov.)、口孔棒球藻(新种)(Rhabdosphaerabucca-pororata sp.nov.)、柿子颗石藻(新种)(Coccolithus persimmonus sp.nov.)。一个未定种是篮石未定种(Scyphosphaera sp.)。这些化石均是在深水断槽相中发现的。  相似文献   

7.
谭励可  于明旭 《地质论评》1997,43(1):33-44,T002
本文报道了在内蒙古赤峰市红花沟石头道村东山,原认为属太古宙的地层中所发现的多门类微体化石群,其大地构造位置的华北地台北缘内蒙地轴东部。化石群包括见于我国南方寒武世梅树阶的软舌螺类,似软舌螺类,棱管壳类,齿形壳类,开腔骨类,原牙形刺类,单板类,球形壳类,口盖化石等;也有本区特有蠕虫管类及藻类化石,共计20属20种(其中2新属3新种,1相似种,10未定种)证明该区原太古宇中的部分地层时代应属晚震旦世一  相似文献   

8.
论大槽子组和碳山坪组的地质时代   总被引:2,自引:0,他引:2  
<正> 大槽子剖面位于云南省宁蒗县城以南约25km处,是原云南省第二区域地质测量队于70年代发现和测制的,并对泥盆纪地层作了划分、对比和命名。由下而上分别是大瓜坪组、大槽子组、碳山坪组、烂泥箐组和干沟组,其中将大瓜坪组划归早泥盆世晚期,大槽子组和碳山坪组分别与艾菲尔阶和吉维特阶对比,烂泥箐组和干沟组分别与弗拉阶和法门阶对应。大槽子剖面地处泥盆系青藏区和华南区交界处(王钰等1982),且地层发育较  相似文献   

9.
The Raskoh arc is about 250 km long, 40 km wide and trends in ENE direction. The arc is convex towards southeast and terminated by the Chaman transform fault zone towards east. This arc is designated as frontal arc of the Chagai-Raskoh arc system. The Late Cretaceous Kuchakki Volcanic Group is the most widespread and previously considered the oldest unit of the the Raskoh arc followed by sedimentary rock formations including Rakhshani Formation (Paleocene), Kharan Limestone (Early Eocene) and Nauroze Formation (Middle Eocene to Oligocene), Dalbandin Formation (Miocene to Pleistocene), and semi-unconsolidated Subrecent and Recent deposits. The Rakhshani Formation is the most widespread and well-exposed unit of the Raskoh arc. During the present field investigation the Rakhshani forma-tion in the southeastern part of the Raskoh arc, is identified as an accretionary complex, which is designated as Raskoh accretionary complex. The Raskoh accretionary comple is subdivided into three units: (a) Bunap sedimen-tary complex, (b) Charkohan radiolarian chert, and (c) Raskoh ophiolite melange. The Bunap sedimentary complex is farther divided into three tectonostratigraphic units viz., northern, middle and southern. Each unit is bounded by thrust faults, which is usually marked by sheared serpentinites, except northern unit, which has gradational and at places faulted contact with the Kuchakki Volcanic Group. The northern unit is mainly composed of allochthonous fragments and blocks of limestone, sandstone, mudstone and the volcanics in dark gray, greenish gray and bluish gray siliceous flaky shale. At places the shale is metamorphosed into phyllite. This unit is thrust over the middle unit, which exhibits relatively a coherent stratigraphy, represented by greenish gray calcareous flaky shale with intercalation of thin beds and lenticular bodies of mudstone, sandstone and limestone. The middle unit is again thrust over the southern unit, which is mainly composed of large exotic blocks of volcanic rocks, limestone, sand-stone, mudstone and conglomerate embedded in dark gray, greenish gray and bluish gray siliceous flaky shale which is generally moderately argillized. The unit is thrust over the Kharan Limestone. During the present field investigation about 350 meter thick sequence of thin-bedded maroon and green chert intercalated with the siliceous flaky shale of the same colour are discovered within this unit, which is found in the southeastern part of the Ras-koh arc. This chert sequence occurs on the margins of a large exotic block (350m X 3 km) of volcaniclastic rocks of unknown origin, which makes an overturned syncline. This chert sequence is developed on its both limbs and has lower faulted contact with the Bunap sedimentary complex. Two samples collected from this chert sequence yielded radiolarian fauna, which include Parvicingula sp., Laxto-rum sp., Parahsuum cf. simplum, Parahsuum sp., Nassellaria gen. et sp. indet., Hsuum cf. Matsuokai., Archaeo-spongoprunum sp., Nassellaria gen. et sp. indet. and Hagias gen. et sp. indet., Tricolocapsa sp., Hsuum sp., Ris-tola sp., Archaeospongoprunum sp. and Tritrabinate gen. et sp. indet. This radiolarian chert sequence represents the late Early to Middle Jurassic pelagic sediment deposited in Ceno-Tethyan ocean floor; prior to the inception of volcanism in the Raskoh arc and accreted with the arc during Late Cretaceous to Eocene along with the Bunap sedimentary complex of Late Jurassic age.  相似文献   

10.
内蒙古赤峰早白垩世昆虫化石的新发现   总被引:7,自引:0,他引:7  
任东  朱会忠  陆有泉 《地球学报》1995,16(4):432-439
本文首次描述了内蒙古自治区赤峰市早白垩世九佛堂组的鞘翅目和异翅目昆虫化石4属5种,其中3新属5新种。这些昆虫化石通过与国内、外相关类群的对比,为该区的地层划分、对比和地质时代的确定,提供了最新的依据。由古生态方面分析,该区为湖沼环境,水体充沛,为古黑龙江流域的一部分。文中里阿龙虱科、沼梭科和中生五节蝽科的材料在国内是首次报道。  相似文献   

11.
新疆巴里坤地区早-中泥盆世四射珊瑚   总被引:3,自引:0,他引:3  
新疆巴里坤地区泥盆纪地层发育齐全层序清楚,化石丰富.是研究泥盆纪地层的一个典型地区.下、中泥盆统盛产四射珊瑚,其中下统的四射瑚珊有Syringaxon zhifangense,Ba-arrndeophyllum multiseptatum,B.raritabulatum,B.graciliseptatum.Taralas-ma jungarensis,T.zhifangensis,Pedderolasma junggarensis,Schindewolfiaxinjiangensis,Enterolasma strictum,Orthopaterophyllum xinjiangense,Sinos-pongophyllum(?) sp.,Kyphophyllum(?)deronia,Altaja xinjiangensis,Iowaphyllumjunggarense,Atelophyllum sp.,Diplochone xinjiangensis;中统有Endophyllumnalivkini zhifangense E.zhifangense,Prismatophyllum xinjiangense,Billingsas-traea(?) magxima,Pseudochlamydophyllum zhifangense,Sinodisphyllum xinjian-gense.Sinospongophyllum barkoense,S.junggarense,keriophyllum sp.等.其中新种18个.与上述四射珊瑚共生的还有大量的床板珊瑚和腕足类.它们共同组成巴里坤地区早-中泥盆世独特的生物群落.  相似文献   

12.
Our results present a taxonomic and palaeoecological study on non-marine gastropods from the latest Cretaceous to Paleocene deposits of the Pingyi Basin, Shandong Province, eastern China. These gastropods are systematically described: three species belonging to three genera including Physa dongtaiensis Gu, 1989, Hydrobia datangensis Yü, 1977, and the newly established species Cyathopoma pingyiensis sp. nov.; two indeterminata genera and species including Truncatelloidea gen. et sp. indet., and Pomatiopsidae gen. et sp. indet. Among them, Truncatelloidea gen. et sp. indet. and Cyathopoma pingyiensis sp. nov. are the dominant species with the longest record. Cyathopoma pingyiensis, sp. nov. is the earliest representative of this widely distributed Asian extant genus. Sedimentological facies analysis of the gastropod-bearing beds suggested that Truncatelloidea gen. et sp. indet. lived in a small pond with a river inlet and a shallow lake, while Ph. dongtaiensis, ?Pomatiopsidae gen. et sp. indet, and ?H. datangensis only thrived in the shallow lake. Cyathopoma pingyiensis sp. nov. inhabited the land area around the shallow lake. Our results showed that no significant species change of the gastropod fauna across the K/Pg (Cretaceous/Paleogene) boundary was observed in the Pingyi Basin.  相似文献   

13.
The Wupata‘erkan Group, also called Wupata‘erkan Formation, distributed in the South Tianshan, Xinjiang,China, mainly consists of gray and dark gray fine-grained clastic rocks, interlayered with volcanic rocks, carbonates and cherts. Some ultra-basic rocks (blocks) punctuate the formation. The formation was variously assigned to Silurian-Middle Devonian, Silurian-Lower Devonian, and pre-Devonian, mainly based on Atrypa bodini Mansuy, Hypothyridina parallelepipedia (Brour.) and Prismatophyllum hexagonum Yoh collected from the limestone interlayers, respectively.However, radiolarian fossils obtained from 24 chert specimens of the Wupata‘erkan Group, mainly include Albaillella sp.cf. A. undulata Deflandre, Albaillella sp. cf. A. paradoxa Deflandre, Albaillella cf. A. deflandrei Gourmelon, Albaillella sp. cf. A. indensis Won, Albaillella sp. cf. A. excelsa Ishiga, Kito and Imoto, Albaillella sp. and Latentifistulidae gen. et. sp.indet., are earliest Carboniferous and Late Permian. The earliest Carboniferous assemblage is characterized by Albaillella sp. cf. A. undulata Deflandre, Albaillella sp. cf. A. paradoxa Deflandre, Albaillella cf. A. deflandrei Gourmelon and Albaillella sp. cf. A. indensis Won, and the Late Permian assemblage by Albaillella sp. cf. A. excelsa Ishiga, Kito and Imoto. This new stratigraphic evidence indicates that the Wupata‘erkan Group is possibly composed of rocks with different ages from Silurian to Permian, and therefore, it is probably an ophiolite mrlange. The discovery of Late Permian Albaillella sp. cf. A. excelsa provides more reliable evidence supporting the existence of a Permian relic ancient oceanic basin in the western part of Xinjiang South Tianshan.  相似文献   

14.
Fossils from the Cambrian to Devonian rocks of southern Thailand, the Langkawi Islands, mainland Kedah, Perlis, north Perak and central West Peninsular Malaysia are listed and reviewed, and their stratigraphy and correlation reassessed. The hitherto anomalous record of the trilobite Dalmanitina from Malaysia is reviewed and found to be of latest Ordovician (Hirnantian) age, rather than Lower Silurian age as previously reported, and is considered a probable synonym of the widespread Mucronaspis mucronata. A new stratigraphical nomenclature is erected for part of the Langkawi, mainland Kedah and Perlis area successions, in which the term Setul Limestone (which stretched from the Ordovician to the Devonian) is abandoned and replaced by the Middle Ordovician Kaki Bukit Limestone, the late Ordovician and early Silurian Tanjong Dendang Formation, the Silurian Mempelam Limestone, and the early Devonian Timah Tasoh Formation, all underlying the paraconformity with the late Devonian Langgun Red Beds. There was a single depositional basin in the generally shallow-water and cratonic areas of southern Thailand, Langkawi, and mainland Kedah and Perlis, in contrast to the deeper-water basin of north Perak. Only Silurian rocks are dated with certainty within another basin in central West Malaysia, near Kuala Lumpur, which were also cratonic and shallow-water, although to the east in west Pahang there are basal Devonian deeper-water sediments with graptolites. The area is reviewed in its position within the Sibumasu Terrane, which, in the Palaeozoic, also included central and northern Thailand, Burma (Myanmar) and southwest China (part of Yunnan Province).  相似文献   

15.
The occurrence of belemnites in Mesozoic sediments of the Pacific guyots is established for the first time (rostra Dimitobelidae gen. et sp. indet. from the late Campanian-Maastrichtian detrital limestone of the DVGI Guyot, Belemnitella? sp. from oolitic limestone of the Gelendzhik Guyot, which are presumably of the Santonian-Maastrichtian age, and Belemnitidae? gen. et sp. indet. from the Maastrichtian oolitic limestone of the Butakov Guyot, the Magellan Rise). In recent years, fossil cephalopods important in stratigraphic and paleobiogeographic aspects have been found at five guyots of that rise. New data on fossil invertebrates from the study region suggest breaks in the sedimentation here at the terminal Maastrichtian, Paleogene, and initial Neogene time. Possible limits of vertical migration in the tropical Pacific are estimated for the Late Cretaceous belemnites based on preliminary results of the oxygen isotope analysis.  相似文献   

16.
<正> 新疆北部阿尔泰山、东、西准噶尔及北天山地区,下、中、上泥盆统皆有床板珊瑚,垂直变化明显,形成了自奥陶纪以来第三个繁盛期。本文将本区泥盆纪床板珊瑚分布规律及其组合特征介绍如下:  相似文献   

17.
Ostracod from the upper Lower to Middle Devonian rocks of the Argentine Precordillera Basin (Talacasto and Punta Negra formations) are studied. One new genus Pircawayra nov. gen., and five species (including three new: Pircawayra gigantea nov. gen. and sp., Lapazites trinodis nov. sp. and Keslingiella? teresae nov. sp.) are defined. The recorded ostracod fauna closely resembles that coeval from Bolivia and South Africa, exhibiting a remarkable endemism, not only at the genus level, but also at the species level. In addition to its low-diversity, the Malvinokaffric ostracod association is also characterized by having large, thick, coarsely ornamented and swollen valves. The similar ostracod composition from the Andean and South African basins suggests faunal exchange between these two areas. Based on the ostracod faunas, the Malvinokaffric Realm is clearly recognizable at least up to the Middle Devonian.  相似文献   

18.
Only two crinoid faunas of Rhuddanian or early Aeronian age have been described hitherto, both from North America. A Rhuddanian pelmatozoan fauna from Haverfordwest, Dyfed, south-west Wales includes the cheirocrinid rhombiferan cystoid Homocystites? sp., plus the following crinoid species: the calceocrinid disparids Calceocrinus turnbulli sp. nov. and Calceocrinus? sp.; the dendrocrinid cladid Dendrocrinus? gasworksensis sp. nov.; the patelliocrinid monobathrid Macrostylocrinus? sp. indet.; columnals of the rhodocrinitid(?) diplobathrid Floricolumnus (col.) sp. cf. F. (col.) girvanensis Donovan and Clark; the rhodocrinitid diplobathrid Chaosocrinus ornatus sp. nov.; and two indeterminate crinoid species. At the familial level this fauna shows strong similarities with coeval, but more diverse, crinoid assemblages from North America, suggesting that endemism did not develop until later in the Silurian.  相似文献   

19.
Lower Devonian corals and stromatoporoids have recently been discovered in limestones among low grade metamorphic rocks on the western margin of the Kon Tum Block (South Viet Nam). This unit has been identified as the Cu Brei Formation. Coral and stromatoporoid species have been described including Squameofavosites aff. spongiosus, Parallelostroma cf. multicolumnum, Amphipora cf. rasilis, A. cf. raritalis, Simplexodictyon cf. artyschtense, Stromatopora cf. boriarchinovi and Stromatopora sp. indet. The Cu Brei Formation is exposed in a small area 6 km in length and 3 km wide at the foot of Cu Brei Mountain (Sa Thay District, Kon Tum Province). As this formation is in marine shelf facies it is probable that further exposures of Lower Devonian sediments may be discovered in the Kon Tum Block. This discovery raises the question of the tectonic history of the metamorphic Kon Tum Block. It is possible that the block was not an area of positive uplift from the beginning of Paleozoic as has been supposed, but was submerged in a marine environment, at least on its outer margins, in the Devonian, and possibly even earlier, in Early Paleozoic.  相似文献   

20.
中国南方泥盆系发现颗石藻   总被引:1,自引:0,他引:1       下载免费PDF全文
颗石藻作为一种超微远洋浮游生物,出现于侏罗纪里阿斯世(Lias),繁盛于晚白垩世至第三纪。最近又有所进展。哈克(Hag,1981)面告,最老的颗石藻出现于石炭纪和二叠纪。本文所报道之颗石藻发现于晚泥盆世,是截至目前为止最老的颗石藻化石。 颗石藻演化迅速,分布广泛,形态特征明显,而且数量众多,对划分对比海相地层有一定的意义。本文只对研究区所采标本的颗石藻进行鉴定、描述和分类。  相似文献   

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