Section of Permian deposits and fusulinids in the Halvan Mountains, Yazd province, Central Iran

The Permian section situated northwest of Tabas in the Halvan Mountains is studied and fusulinids occurring in the section are described. The Chili, Sartakht, and Hermez formations distinguished in the section are separated by horizons of bauxitic laterite and belong to the Khan Group formerly ranked as a synonymous formation. Fusulinids occur at two levels in the section. The lower one confined to the Chili Formation yields the so-called Kalaktash fusulinid assemblage of the late Sakmarian age. The second late Asselian assemblage has been discovered in pebbles from conglomerate-breccia in the basal laterite of the Sartakht Formation. A brief characterization of fusulinids is presented and three new species are described. The new Benshiella genus is discriminated from the Rugosofusulinidae family. As Skinner and Wilde (1965, 1966) changed the original diagnosis of the Pseudofusulina genus, we suggest, regarding all species, which have been attributed to this genus but do not satisfy the new diagnosis, as representing the new Nonpseudofusulina genus.     

Fusulinids from the lower Permian Chili Formation of the Rahdar section, Kalmard block, Central Iran

Fusulinids from the Chili Formation are studied in the Rahdar section of the Kalmard block west of the town of Tabas, Central Iran. The Kalaktash and Halvan fusulinid complexes are revealed in the section. The location of the Halvan complex over the Kalaktash one confirms its relatively younger (Late Sakmarian-Early Artinskian) age. The Halvan complex was previously considered to be Asselian. Three new species (Parazellia rahdarensis, Nonpseudofusulina bozorgniai, and Eoparafusulina rahdarensis) and one new subspecies (Benshiella khorasanensis compacta) are described.     

New Permian Aliyak and Kariz Now formations,Alborz Basin,NE Iran: correlation with the Zagros Mountains and Oman

Two new Permian‐aged formations ‘Kariz Now Formation’ and ‘Aliyak Formation’ are proposed for a 65–150 m‐thick succession in the Kariz Now area, with the type section for both (79.5 m thick) located 9 km northeast of Aliyak village ca. 100 km southeast of Mashhad city, northeastern Iran. The lower Kariz Now Formation is composed of siliciclastics. The age of this Formation is poorly constrained but its correlation with the Shah Zeid Formation in the Central Alborz suggests a possible Asselian‐Hermagorian age for the Kariz Now Formation, which implies a hiatus of Yakhtashian–mid Midian (Artinskian–mid Capitanian) age between the siliciclastics of the Kariz Now Formation and carbonates of the disconformably overlying Aliyak Formation. There is also the possibility of a potential correlation of this Formation with the Kungurian Faraghan Formation in the Zagros area. The succeeding Aliyak Formation is mostly composed of carbonate rocks capped by a thin basaltic lava flow. The Aliyak Formation is unconformably overlain by dolostones that are correlated with the Middle Triassic Shotori Formation. Samples were collected from the Kariz Now and Aliyak formations, but fossils were only recovered from the Aliyak Formation. These include calcareous algae, small foraminiferans, fusulinids, crinoid stems and brachiopods. The recovered fusulinid assemblage from the Aliyak Formation is consistent with that of the upper Capitanian Monodiexodina kattaensis–Codonofusiella erki and Afghanella schencki–Sumatrina brevis zones of the Zagros Mountains and with the upper part of the Ruteh Fm in the Alborz Mountains. Although not radiometrically dated, the basaltic lava flow most probably corresponds to similar basaltic lava flows occurring in the uppermost part of the Ruteh Formation in Central Alborz. Thus, the Permian in the studied region developed in a basin that extended westward as far as the Central Alborz. A late Capitanian age for the Aliyak Formation implies it correlates with the Capitanian KS5 in Al Jabal Al‐Akhdar in Oman, with Aliyak Unit 5 potentially representing the Permian maximum flooding surface MFS P25. Copyright © 2014 John Wiley & Sons, Ltd.     

贺兰山北段石炭纪和二叠纪植物群

贺兰山北段石炭纪和二叠纪植物化石经鉴定,计有39属104种。讨论了植物群的性质,划分了5个组合,即(1)晚石炭世早期Bothrodendroncirculare—Mesocalamitescistiformis组合;(2)晚石炭世中期Lepidodendronsubrhombicum—Conchophyllumrichthofenii组合;(3)晚石炭世晚期Lepidodendronszeianum—Neuropterisovata组合;(4)早二叠世早期Lepido dendronposthumii—Callipteridiumkoraiense组合和(5)早二叠世晚期Caulopteriswudaensis—Paratingiadatongensis组合。这5个组合的代表岩组分别为红土洼组、羊虎沟组、太原组下部、太原组中上部和山西组。其地质时代大致相当于纳缪尔B—C期、维斯发期、斯蒂芬期、阿赛尔期、萨克马尔期和阿丁斯克期。植物群含有大量的华夏型分子,为典型的华夏植物群。此外还讨论了植物群的演化。     

东昆仑西段早—中二叠世生物礁相地层层序

本文以大量化石资料为基础，结合生物礁研究成果，重建了东昆仑造山带西段早-中二叠世礁相地层层序，确定了地层时代归属。礁相地层自下而上分为5个岩组。阿其克库勒组为陆块边缘碎屑陆棚之上的碳酸盐沉积和丘状生物礁建造，可建立Ting类Schwagerina-Eoparafusulina组合带和Chalaroschwagerina-Pseudofusulina Parafecunda组合带，对比为下二叠统的中上冲淡，查德尔塔格组为海侵期巨厚块状障壁礁碳酸盐岩，包含Ting类Mis-ellina claudiae组合和一个未定名组合，属中二叠世栖霞期，青石山组和碧云山组为同时异相沉积，前者以礁核相骨架灰岩为主，厚度巨大；后者为礁后-泻湖相黑色富有机质岩层，厚度较薄，二岩组同属Ting类Polydiexodina-Neoschwagerina组合带内Cancerllina liuzhiensis亚带、Neoschwagerina simplex亚带和Afghanella schencki亚带的层位，时代为中二叠世茅口早一中期，喀尔瓦组为类复理石相砂板岩平恶意泥丘灰岩，含Afghanella schencki亚带的Ting化石，地层时代与青石山组（或碧云山组）上部相当。     

Stratigraphy and palynostratigraphy, Karoo Supergroup (Permian and Triassic), mid-Zambezi Valley, southern Zambia

The Karoo Supergroup outcropst in the mid-Zambezi Valley, southern Zambia. It is underlain by the Sinakumbe Group of Ordovician to Devonian age. The Lower Karoo Group (Late Carboniferous to Permian age) consists of the basal Siankondobo Sandstone Formation, which comprises three facies, overlain by the Gwembe Coal Formation with its economically important coal deposits, in turn overlain by the Madumabisa Mudstone Formation which consists of lacustrine mudstone, calcilutite, sandstone, and concretionary calcareous beds. The Upper Karoo Group (Triassic to Early Jurassic) is sub-divided into the coarsely arenaceous Escarpment Grit, overlain by the fining upwards Interbedded Sandstone and Mudstone, Red Sandstone; and Batoka Basalt Formations.Palynomorph assemblages suggest that the Siankondobo Sandstone Formation is Late Carboniferous (Gzhelian) to Early Permian (Asselian to Early Sakmarian) in age, the Gwembe Coal Formation Early Permian (Artinskian to Kungurian), the Madumabisa Mudstone Late Permian (Tatarian), and the Interbedded Sandstone and Mudstone Early or Middle Triassic (Late Scythian or Anisian). The marked quantitative variations in the assemblages are due partly to age differences, but they also reflect vegetational differences resulting from different paleoclimates and different facies.The low thermal maturity of the formations (Thermal Alteration Index 2) suggests that the rocks are oil prone. However, the general scarcity of amorphous kerogen, such as the alga Botryococcus sp., and the low proportion of exinous material, indicates a low potential for liquid hydrocarbons. Gas may have been generated, particularly in the coal seams of the Gwembe Coal Formation, that are more deeply buried.     

First record of Gzhelian and Asselian Fusulinids from the Vazhnan Formation (Sanandaj-Sirjan zone of Iran)

The Vazhnan Formation, formerly attributed to the Sakmarian is now shown to be of the Gzhelian-Asselian age. Accordingly it is correlative with the concurrent Zaladou Formation of Central Iran and Dorud Group of Alborz. This suggests a vast transgression that covered the greater part of the Iranian territory in the terminal Carboniferous-initial Permian. The work includes brief characterization of fusulinids found in the formation section.     

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

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。     

Fusulinid biostratigraphy of the Lower Permian Zweikofel Formation (Rattendorf Group; Carnic Alps,Austria) and Lower Permian Tethyan chronostratigraphy

The Zweikofel Formation of the Rattendorf Group in the Carnic Alps (Austria) is 95–102 m thick and consists of a cyclic succession of thin‐ to thick‐bedded fossiliferous limestone and intercalated thin intervals of siliciclastic sediment. The siliciclastic intervals were deposited in a shallow marine nearshore environment. The variety of carbonate facies indicates deposition in a shallow neritic, normal‐saline, low‐ to high‐energy environment. The Zweikofel Formation is characterized by a paracyclic vertical arrangement of facies and represents sedimentary sequences that are not well understood elsewhere in the Tethys. Fusulinids and conodonts from the upper Grenzland and Zweikofel formations in the Carnic Alps clearly suggest that what has been called ‘Sakmarian’ in the Tethys includes both the Sakmarian and Artinskian stages of the Global Time scale. Fusulinids from the lower part of the Zweikofel Formation at Zweikofel closely resemble those of the Grenzland Formation and approximately correlate with the upper part of the Sakmarian and lower part of the Artinskian of the Global Time scale. The upper part of the Zweikofel Formation correlates approximately with the lower‐middle (?) parts of the Artinskian Stage of the Global Time scale. A new regional Hermagorian Stage of the Tethyan scale is proposed between the Asselian and Yakhtashian. The lower boundary of the Hermagorian Stage is proposed to be located at the base of bed 81 in the 1015 section of Darvaz (Tadzhikistan). The boundary between the Hermagorian and Yakhtashian stages is placed at the base of bed 73 in the Zweikofel section at Zweikofel, Carnic Alps. In the Darvaz region, Tadzhikistan, the type area for the Yakhtashian Stage, this boundary has never been precisely defined. The entire fusulinid assemblage of the upper part of the Grenzland and Zweikofel formations reported herein includes 62 species of 18 genera, of which one subgenus and 12 species and subspecies are new. Copyright © 2012 John Wiley & Sons, Ltd.     

川西波格西地区晚古生代岩石地层厘定

在对四川西部巴塘县波格西地区晚古生代地层剖面研究的基础上,从岩性、岩相分析入手,将该区地层划分为６个组级岩石地层单位。根据所含化石确定地层形成时代为泥盆纪至二叠纪。在与邻区岩石地层对比基础上,将木里小区前人已建立的崖子沟组延入本区,修订了波格西组和龙巴组含义,新建了那来组、夺给组和帮相组,选定了剖面层型。从而完善了稻城小区晚古生代岩石地层系统。     

Palynological assemblages of non-marine rocks at the Permian–Triassic boundary, western Guizhou and eastern Yunnan, South China

Marine and non-marine facies of the Permian–Triassic boundary stratigraphic set (PTBST) are well developed in South China. Palynological assemblages enable subdivision and correlation of the Permian–Triassic boundary (PTB) rocks. Three palynological assemblages are recognized across the PTBST in two terrestrial PTB sections in western Guizhou and eastern Yunnan, South China. Assemblage 1 (Xuanwei Formation) is a Late Permian palynological assemblage dominated by ferns and pteridosperms, with minor gymnosperms. Most taxa are typical long-ranging Paleozoic forms, but the appearance of Lueckisporites confirms a Late Permian age for this assemblage. Assemblage 2 (PTBST) is marked by an abrupt decrease in palynomorph abundance and diversity, and thriving fungal/algal(?) spores. Assemblage 2 is still dominated by ferns and pteridosperms, with a few gymnosperms, but is characterized by a mixed palynoflora containing both Late Permian and Early Triassic elements. Most taxa are typical Late Permian ones also found in Assemblage 1, however, some taxa of Early Triassic aspect, e.g. Lundbladispora and Taeniaesporites, appeared for the first time. In Assemblage 3 (top Xuanwei Formation and Kayitou Formation), the proportion of gymnosperm pollen increases rapidly, exceeding that of ferns and pteridosperms, but the abundance of palynomorphs is still low. Typical Early Triassic taxa (such as Lundbladispora, Aratrisporites and Taeniaesporites) are present in greater abundance and confirms an Early Triassic age for this assemblage.     

Stratigraphic and palaeoenvironmental framework of the Early Permian sequence in the Salt Range, Pakistan

The Early Permian Gondwana regime succession of the Nilawahan Group is exposed only in the Salt Range of Pakistan. After a prolonged episode of non-deposition that spanned much of the Palaeozoic, the 350?m thick predominantly clastic sequence of the Nilawahan Group records a late glacial and post-glacial episode in which a range of glacio-fluvial, marine and fluvial environments evolved and accumulated. The Early Permian succession of the Salt Range has been classified into four formations, which together indicates a changing climatic regime during the Early Permian in the Salt Range region. The lower-most, Tobra Formation unconformably overlies a Cambrian sequence and is composed of tillite, diamictite and fresh water facies, which contain a floral assemblage (Gangamopteris and Glossopteris) that confirms an Asselian age. The Tobra Formation is overlain by marginal marine deposits of the Dandot Formation (Sakmarian), which contain an abundant brachiopods assemblage (Eurydesma and Conularia). Accumulation of the Dandot Formation was terminated by a regional sea-level fall and a change to the deposition of the fluvial deposits of the Warchha Sandstone (Artinskian). The Warchha Sandstone was deposited by high sinuosity meandering, avulsion prone river with well developed floodplains. This episode of fluvial sedimentation was terminated by a widespread marine transgression, as represented by the abrupt upward transition to the overlying shallow marine Sardhai Formation (Kungurian). The Early Permian Gondwana sequence represented by the Nilawahan Group is capped by predominantly shallow shelf carbonate deposits of the Tethyan realm. The sedimentologic and stratigraphic relationship of these four lithostratigraphic units in the Salt Range reveals a complex stratigraphic history for the Early Permian, which is mainly controlled by eustatic sea-level change due to climatic variation associated with climatic amelioration at the end of the major Gondwana glacial episode, and the gradual regional northward drift to a lower latitude of the Indian plate.     

新疆塔里木盆地哈拉奇地区晚石炭世一早二叠世哈拉奇组的建立

哈拉奇组为新疆阿合奇县开展1：5万区域地质矿产调查工作时建立的岩石地层单位,分布在新疆阿合奇县哈拉奇地区北部,主要为一套深水碳酸盐沉积,与该区南部属碳酸盐台地沉积的康克林组在岩性、岩石组合及古生物组合上形成明显的差别。通过对该组重力流成因的生物屑砾屑灰岩中古生物化石的研究,确定其筵带为Triticites带和Pseudoschwagerina带,进而确定该组地质时代为晚石炭世-早二叠世,与南区康克林组为同时异相沉积。哈拉奇组的建立完善了该地区上石炭统一下二叠统的地层系统,确定了该地区晚石炭世-早二叠世台地边缘斜坡相的存在,对塔西北地区晚石炭世-早二叠世岩相古地理研究具有重要意义。     

Research on Outcrop Sequence Stratigraphy of Permian in Middle—Lower Yangtze Region

According to the latest International Chronostratigraphic Scheme (ICS, 2000), the Permian in the Middle-Lower Yangtze region of South China can e divided into three series and nine stages relevant to the traditional six stages of South China. From Assellian to Changxingian of Permian, 44 Main age range, the strata are composed of 14 third-order sequences, each of which is 3.14 Ma in average age range. There is one third-order sequence of Zisongian, equivalent to middle and upper Chuanshan Formation or equal to Asselian and two thirds of Sakmarian. There are two third-order sequences, corresponding to Liang-shan Formation or Zhenjiang Formation and upper Chuanshan Formation, which are assigned to Longlingian, coinciding with Artinskian and one third of Sakmarian. In addition, three third-order sequences, equal to Qixia Formation, are attributed to Chhsian, corresponding to Kubergandian and one third of Roadian. Four third-order sequences, comprising Gufeng, Maokou, Yanqiao,Yinping and Wuxue formations, are assigned to Maokouan, equivalent to two thirds of Roadian, Wordian and Capitanian. Two third-order sequences, equal to Longtan Formation or Wujiaping Formation, are included in Wuchiapingian. Other two third-order sequences, corresponding to changxing Formation or Dalong Formation, are assigned to Changhsingian. In brief, these above third-order sequences can be incorporated into 4 sequences sets.     

西藏北部申扎地区德日昂玛-下拉山石炭二叠系生物地层划分

吉林地质调查院在西藏北部申扎地区进行地质调查时，对石炭纪一二叠纪地层进行了详细研究，自下而上划分为永珠组、拉嘎组、昂杰组、下拉组和木纠错组，并进行了生物地层划分，在永珠组建立了Gnathodus girtyi-Gnathodus tezanus牙形刺组合、Goniatites菊石带、Choristites-Spirigerella腕足组合和Trigonatreta cf．paucicostulata-Elivella baschkirica腕足组合；昂杰组建立了Spiriferella-Costiferina腕足组合；下拉组建立了Ipciphyllure-Waagenophyllum-Wentzelellites珊瑚组合、Dielasma millepunctatum-psudoantiquatonia mutabilis腕足组合和Neoschwagerina筵带。     

新甘交界北山地区早二叠世红柳河群的建立

经1:5万区域地质调查研究,北山地区原红柳河组规模巨大,岩性、岩相差异明显,按岩石地层划分原则,应进一步分组.原红柳河组内部有4套岩性、岩相差异较大的岩石组合,以3次砾岩事件和1次火山岩事件为标志,代表了4个不同的沉积阶段,与之对应出现了4个重要的沉积(不整合)界面.依据这4个界面对早二叠世红柳河组进行了重新划分,即下二叠统河西组(P1h)、红柳村组(P1hl)、芦苇井组(P1l)和红柳井组(P1hj).在河西组采集到大量的腕足、苔藓虫等海相动物化石,在芦苇井组第二岩性段含炭粉砂岩中获孢粉化石组合,其时代属于二叠纪.本区新建的4个组实际上是由一个规模较大的老组再分组的结果.按岩石地层单位修定的要求,建议原红柳河组上升为群.     

Smaller foraminifers from the Permian of Central Iran

Six assemblages of smaller foraminifers are first distinguished and described from sections of the Kalmard tectonic block, Central Iran. The assemblages that have been studied are correlated with concurrent assemblages from the East European platform, Cis-Urals, Darvaz, Northern Pamir, and some other regions of the Tethyan Realm. The results of correlation and available data on fusulinids and conodonts occurring in association with smaller foraminifers are used for dating the assemblages whose distribution ranges span the stratigraphic interval from the early Sakmarian (lower assemblage) up to the Kubergandian (uppermost assemblage). New species Frondina iranica sp. nov. discovered in the study region is described.     

Stratigraphy, biostratigraphy and C-isotopes of the Permian–Triassic non-marine sequence at Dalongkou and Lucaogou, Xinjiang Province, China

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.     

The Age and Character of the Yu''erhong Flora from Yumen, Gansu

From a fresh field investigation, it has been ascertained that the Late Palaeozoic Yu'erhong (Yuernhung) flora from Yu'erhong, Yumen, Gansu, northwestern China, studied by Bohlin in 1971 includes plants from the Westphalian Yangfukou Formation and the Stephanian to Sakmarian Taiyuan Formation. The Yu'erhong flora from the Yanghukou Formation is dominated by Euramerican elements with a few elements of the Cathaysian flora. No Angarian elements have be found in this section for lack of Late Permian strata. The specimens studied by Bohlin might possibly come from the upper part of the Upper Permian at tne southeastern corner . of the Yu'erhong basin. Those fossils from different horizons and localities might be mixed with each other during collection ;so they fail to reflect the exact horizon of certain plant fossils.