Middle and Late Permian radiolarian fossils yielding from siliceous rock pebbles in the Middle and Upper Permian Maizuru Group, Southwest Japan.

NOTE: This article was published in a former series of GEUS Bulletin. Please use the original series name when citing this article, for example: Kresten Nielsen, J., & Hanken, N.-M. (2002). Late Permian carbonate concretions in the marine siliciclastic sediments of the Ravnefjeld Formation, East Greenland. Geology of Greenland Survey Bulletin, 191, 126-132. https://doi.org/10.34194/ggub.v191.5140 _______________ This investigation of carbonate concretions from the Late Permian Ravnefjeld Formation in East Greenland forms part of the multi-disciplinary research project Resources of the sedimentary basins of North and East Greenland (TUPOLAR; Stemmerik et al. 1996, 1999). The TUPOLAR project focuses on investigations and evaluation of potential hydrocarbon and mineral resources of the Upper Permian – Mesozoic sedimentary basins. In this context, the Upper Permian Ravnefjeld Formation occupies a pivotal position because it contains local mineralisations and has source rock potential for hydrocarbons adjacent to potential carbonate reservoir rocks of the partly time-equivalent Wegener Halvø Formation (Harpøth et al. 1986; Surlyk et al. 1986; Stemmerik et al. 1998; Pedersen & Stendal 2000). A better understanding of the sedimentary facies and diagenesis of the Ravnefjeld Formation is therefore crucial for an evaluation of the economic potential of East Greenland.

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Sedimentology and geochemistry of Middle–Upper Permian in northwestern Turpan–Hami Basin, China: Implication for depositional environments and petroleum geology

Energy Exploration & Exploitation ◽

10.1177/0144598718779100 ◽

2018 ◽

Vol 36 (4) ◽

pp. 910-941

Author(s):

Jian Song ◽

Zhidong Bao ◽

Xingmin Zhao ◽

Yinshan Gao ◽

Xinmin Song ◽

...

Keyword(s):

Depositional Environment ◽

Saline Water ◽

Depositional Environments ◽

Source Rocks ◽

Petroleum Exploration ◽

Upper Permian ◽

Late Permian ◽

Humid Climate ◽

Mountain Area ◽

Volcanic Source

Studies have found that the Permian is another important stratum for petroleum exploration except the Jurassic coal measures within Turpan–Hami Basin recently. However, the knowledge of the depositional environments and its petroleum geological significances during the Middle–Late Permian is still limited. Based on the analysis about the sedimentological features of the outcrop and the geochemical characteristics of mudstones from the Middle Permian Taerlang Formation and Upper Permian Quanzijie Formation in the Taoshuyuanzi profile, northwest Turpan–Hami Basin, this paper makes a detailed discussion on the Middle–Late Permian paleoenvironment and its petroleum geological significances. The Middle–Upper Permian delta–lacustrine depositional system was characterized by complex vertical lithofacies assemblages, which were primarily influenced by tectonism and frequent lake-level variations in this area. The Taerlang Formation showed a significant lake transgression trend, whereas the regressive trend of the Quanzijie Formation was relatively weaker. The provenance of Taerlang and Quanzijie Formations was derived from the rift shoulder (Bogda Mountain area now) to the north and might be composed of a mixture of andesite and felsic volcanic source rocks. The Lower Taerlang Formation was deposited in a relatively hot–dry climate, whereas the Upper Taerlang and Quanzijie Formations were deposited in a relatively humid climate. During the Middle–Late Permian, this area belonged to an overall semi-saline water depositional environment. The paleosalinity values showed stepwise decreases from the Lower Taerlang Formation to the Upper Quanzijie Formation, which was influenced by the changes of paleoclimate in this region. During the Middle–Late Permian, the study area was in an overall anoxic depositional environment. The paleoenvironment with humid climate, lower paleosalinity, anoxic condition, and semi-deep to deep water during the deposition of the Upper Taerlang Formation was suitable for the accumulation of mudstones with higher TOC values.

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Stratigraphy and depositional history of the Upper Palaeozoic and Triassic sediments in the Wandel Sea Basin, central and eastern North Greenland

Rapport Grønlands Geologiske Undersøgelse ◽

10.34194/rapggu.v143.8056 ◽

1989 ◽

Vol 143 ◽

pp. 21-45

Author(s):

L Stemmerik ◽

E Håkansson

Keyword(s):

Early Carboniferous ◽

Upper Permian ◽

Lower Permian ◽

Late Permian ◽

The West ◽

Depositional History ◽

Lower Carboniferous ◽

Upper Carboniferous ◽

Lithostratigraphic Units ◽

History Of

A lithostratigraphic scheme is erected for the Lower Carboniferous to Triassic sediments of the Wandel Sea Basin, from Lockwood Ø in the west to Holm Land in the east. The scheme is based on the subdivision into the Upper Carboniferous - Lower Permian Mallemuk Mountain Group and the Upper Permian - Triassic Trolle Land Group. In addition the Upper Carboniferous Sortebakker Formation and the Upper Permian Kap Kraka Formation are defined. Three formations and four members are included in the Mallemuk Mountain Group. Lithostratigraphic units include: Kap Jungersen Formation (new) composed of interbedded limestones, sandstones and shales with minor gypsum - early Moscovian; Foldedal Formation composed of interbedded limestones and sandstones -late Moseovian to late Gzhelian; Kim Fjelde Formation composed of well bedded Iimestones - late Gzhelian to Kungurian. The Trolle Land Group includes three formations: Midnatfjeld Formation composed of dark shales, sandstones and limestones - Late Permian; Parish Bjerg Formation composed of a basal conglomeratic sandstone overlain by shales and sandstones - ?Early Triassic (Scythian); Dunken Formation composed of dark shales and sandstones - Triassic (Scythian-Anisian). The Sortebakker Formation (new) is composed of interbedded sandstones, shales and minor coal of floodplain origin. The age is Early Carboniferous. The Kap Kraka Formation (new) includes poorly known hematitic sandstones, conglomerates and shales of Late Permian age.

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Croonian lecture : The origin of mammals

Proceedings of the Royal Society of London. Series B, Containing Papers of a Biological Character ◽

10.1098/rspb.1913.0061 ◽

1913 ◽

Vol 87 (592) ◽

pp. 87-88

Keyword(s):

Single Case ◽

Lower Jurassic ◽

Upper Permian ◽

Occipital Condyle ◽

Steady Increase ◽

Lower Permian ◽

Secondary Palate ◽

Middle And Upper Permian ◽

Higher Types ◽

Evolution Of Mammals

An endeavour is made to trace the evolution of mammals from Cotylosaurian ancestors through the carnivorous Therapsida. In Upper Carboniferous times the line probably passed through some primitive generalised Pelycosaurs; in Lower Permian through primitive, probably Therocephalian, Therapsids. In Middle and Upper Permian the line passed through the Gorgonopsia. In Triassic times the mammalian ancestors were small generalised Cynodonts. In Lower Jurassic the mammals are so Cynodont-like, and the Cynodonts so mammal-like, that in no single case are we absolutely certain which is which. In the Therocephalia, the Gorgonopsia, and the Cynodontia, the skull is very mammal-like. The zygomatic arch is, as in mammals, formed by the jugal and the squamosal. The teeth are divided into incisors, canines and molars. In the later Gorgonopsians there is an imperfect secondary palate; in Cynodonts a complete secondary palate as in mammals. In Permian Therapsids there is a single occipital condyle; in the Triassic Cynodonts there may he a single condyle slightly divided or two exoccipital condyles. There is, on passing from earlier to later types, a steady increase in the size of the dentary and decrease in the size of the other elements of the jaw. The quadrate also becomes much reduced in the higher types. In Gorgonopsians and probably all earlier types the arch of the atlas is a pair of bones; in Cynodonts, as in mammals, there is a single arch.

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Tectonic Evolution of the West Bogeda: Evidences from Zircon U-Pb Geochronology and Geochemistry Proxies, NW China

Minerals ◽

10.3390/min10040341 ◽

2020 ◽

Vol 10 (4) ◽

pp. 341

Author(s):

Yalong Li ◽

Wei Yue ◽

Xun Yu ◽

Xiangtong Huang ◽

Zongquan Yao ◽

...

Keyword(s):

Tectonic Evolution ◽

Tectonic Setting ◽

Continental Rift ◽

Middle Permian ◽

Upper Permian ◽

Late Permian ◽

Island Arcs ◽

The West ◽

Structural Deformations ◽

Tian Shan

The Bogeda Shan (Mountain) is in southern part of the Central Asian Orogenic Belt (CAOB) and well preserved Paleozoic stratigraphy, making it an ideal region to study the tectonic evolution of the CAOB. However, there is a long-standing debate on the tectonic setting and onset uplift of the Bogeda Shan. In this study, we report detrital zircon U-Pb geochronology and whole-rock geochemistry of the Permian sandstone samples, to decipher the provenance and tectonic evolution of the West Bogeda Shan. The Lower-Middle Permian sandstone is characterized by a dominant zircon peak age at 300–400 Ma, similar to the Carboniferous samples, suggesting their provenance inheritance and from North Tian Shan (NTS) and Yili-Central Tian Shan (YCTS). While the zircon record of the Upper Permian sandstone is characterized by two major age peaks at ca. 335 Ma and ca. 455 Ma, indicating the change of provenance after the Middle Permian and indicating the uplift of Bogeda Shan. The initial uplift of Bogeda Shan was also demonstrated by structural deformations and unconformity occurring at the end of Middle Permian. The bulk elemental geochemistry of sedimentary rocks in the West Bogeda Shan suggests the Lower-Middle Permian is mostly greywacke with mafic source dominance, and tectonic setting changed from the continental rift in the Early Permian to post rift in the Middle Permian. The Upper Permian mainly consists of litharenite and sublitharenite with mafic-intermediate provenances formed in continental island arcs. The combined evidences suggest the initial uplift of the Bogeda Shan occurred in the Late Permian, and three stages of mountain building include the continental rift, post-rift extensional depression, and continental arc from the Early, Middle, to Late Permian, respectively.

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Late Permian Boreal-Tethyan mixed brachiopod fauna from the Maizuru Belt, southwest Japan: Fossil evidence for the tectono-sedimentological setting of the Maizuru Group

The Journal of the Geological Society of Japan ◽

10.5575/geosoc.112.510 ◽

2006 ◽

Vol 112 (8) ◽

pp. 510-518 ◽

Cited By ~ 6

Author(s):

Jun-ichi Tazawa

Keyword(s):

Late Permian ◽

Southwest Japan ◽

Fossil Evidence ◽

Brachiopod Fauna

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Inozoan calcareous Porifera from the Permian reefs in South China

Journal of Paleontology ◽

10.1017/s0022336000036489 ◽

1989 ◽

Vol 63 (6) ◽

pp. 778-800 ◽

Cited By ~ 24

Author(s):

J. Keith Rigby ◽

Fan Jiasong ◽

Zhang Wei

Keyword(s):

South China ◽

Growth Form ◽

Carbonate Platform ◽

Upper Permian ◽

General Nature ◽

Late Paleozoic ◽

Changxing Formation ◽

Middle And Upper Permian ◽

Eastern Sichuan

Inozoans are described from patch reefs on the carbonate platform of eastern Sichuan, from the uppermost Permian Laolongdong reefs in the Changxing Formation (Kazanian–Tatarian) at Beipei, northwest of Chongqing, and from Middle and Upper Permian reefs from the Maokou (Kungurian), Wujiaping (Ufimian), and Changxing Formations at Xiangbo, Longlin County, in northwestern Guangxi. Classification of inozoans, particularly late Paleozoic ones, is still in a state of flux, but genera recognized to date can be keyed using the general nature of the spongocoel, canals, and growth form.New genera described are Intratubospongia, Grossotubenella, Cavusonella, and Radicanalospongia. The new species described are Stellispongia radiata, S. minor, Peronidella beipeiensis, P. regulara, P. parva, Intratubospongia typica, I. tenuiperforata, I. multisi-phonata, I. minima, Grossotubenella parallela, Cavusonella caverna, and Radicanalospongia normala. A Corynella that is not identifiable to species and a sphinctozoan-like inozoan(?) sp. A that has a fibrous-appearing internal skeleton but is poorly preserved are also described. Inozoans and other sponges are major frame-builders in the Permian reefs of South China and our fauna is one of the most diverse late Paleozoic assemblages described to date.

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