BRYOZOAN-ALGAL PATCH-REEFS IN THE UPPER PERMIAN LOWER MAGNESIAN LIMESTONE OF YORKSHIRE, NORTHEAST ENGLAND

1981 ◽  
pp. 187-202 ◽  
Author(s):  
DENYS B. SMITH
Keyword(s):  
Upper Permian ◽  
Patch Reefs

Sphinctozoan sponges from the Permian reefs of South China

1989 ◽  
Vol 63 (4) ◽  
pp. 404-439 ◽  
Author(s):  
J. K. Rigby ◽  
Fan Jiasong ◽  
Zhang Wei
Keyword(s):  
New Species ◽  
South China ◽  
Middle Permian ◽  
Upper Permian ◽  
Late Permian ◽  
New Genera ◽  
Patch Reefs ◽  
New Family ◽  
Eastern Sichuan ◽  
New Occurrences

Middle and Late Permian sphinctozoan sponges described here are from the Middle Permian Maokou and the Upper Permian Wujiaping and Changxing Formations. Most are from near Xiangbo, northwestern Guangxi, but a few are from Upper Permain patch reefs from Laolongdong in eastern Sichuan. The new genera, the porateImbricatocoeliaand the aporateGlomocystospongia, are described, the latter as the type genus for the new family Glomocystospongiidae. New species described includeAmblysiphonella specialis, Amblysiphonella spinosa, Amblysiphonellasp. A,Amblysiphonellasp. B,Colospongia maxima, Colospongiasp. A,Imbricatocoelia elongata, I. irregulara, I. obconica, I. paucipora, Neoguadalupia explanata, Subascosymplegma?paracatenulata, Rhabdactinia depressa, R. irregulara, R. squamula, Salzburgia nana, Glomocystospongia gracilis, Sollasia absita, andS. spheroida. New occurrences ofAmblysiphonella merlai? Parona, 1933,Lichuanospongia typicaZhang, 1983,Polycystocoelia huajiapingensisZhang, 1983,Intrasporeocoelia hubeiensisFan and Zhang, 1985,Rhabdactinia columnariaYabe and Sugiyama, 1934,Uvanella irregularaOtt, 1967,Stromatocoelia asiaticaZhang and Fan (in Fan and Zhang, 1985), andTebagathalamia cylindricumSenowbari-Daryan and Rigby, 1988, are reported. The described assemblage represents the most diverse Permian sphinctozoan sponge fauna known from Asia.

Fish community structure, habitat complexity, and soundscape characteristics of patch reefs in a tropical, back-reef system

2019 ◽  
Vol 609 ◽  
pp. 33-48 ◽  
Author(s):  
RP Lyon ◽  
DB Eggleston ◽  
DR Bohnenstiehl ◽  
CA Layman ◽  
SW Ricci ◽  
...  
Keyword(s):  
Community Structure ◽  
Habitat Complexity ◽  
Fish Community ◽  
Back Reef ◽  
Fish Community Structure ◽  
Patch Reefs ◽  
Reef System

Hydrothermal activity in the Upper Permian Ravnefjeld Formation of central East Greenland – a study of sulphide morphotypes

1998 ◽  
pp. 81-87
Author(s):  
Jesper Kresten Nielsen ◽  
Mikael Pedersen
Keyword(s):  
Base Metal ◽  
Early Period ◽  
Sedimentary Basins ◽  
Hydrothermal Activity ◽  
Source Rocks ◽  
Upper Permian ◽  
Thermal Activity ◽  
East Greenland ◽  
The North ◽  
Alum Shale

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., & Pedersen, M. (1998). Hydrothermal activity in the Upper Permian Ravnefjeld Formation of central East Greenland – a study of sulphide morphotypes. Geology of Greenland Survey Bulletin, 180, 81-87. https://doi.org/10.34194/ggub.v180.5090 _______________ Bituminous shales of the Ravnefjeld Formation were deposited in the subsiding East Greenland basin during the Upper Permian. The shales are exposed from Jameson Land in the south (71°N; Fig. 1) to Clavering Ø in the north (74°20′N) and have attracted considerable attention due to their high potential as hydrocarbon source rocks (Piasecki & Stemmerik 1991; Scholle et al. 1991; Christiansen et al. 1992, 1993a, b). Furthermore, enrichment of lead, zinc and copper has been known in the Ravnefjeld Formation on Wegener Halvø since 1968 (Lehnert-Thiel 1968; Fig. 1). This mineralisation was assumed to be of primary or early diagenetic origin due to similarities with the central European Kupferschiefer (Harpøth et al. 1986). Later studies, however, suggested base metal mineralisation in the immediately underlying carbonate reefs to be Tertiary in age (Stemmerik 1991). Due to geographical coincidence between the two types of mineralisation, a common history is a likely assumption, but a timing paradox exists. A part of the TUPOLAR project on the ‘Resources of the sedimentary basins of North and East Greenland’ has been dedicated to re-investigation of the mineralisation in the Ravnefjeld Formation in order to determine the genesis of the mineralisation and whether or not primary or early diagenetic base metal enrichment has taken place on Wegener Halvø, possibly in relation to an early period of hydrothermal activity. One approach to this is to study the various sulphides in the Ravnefjeld Formation; this is carried out in close co-operation with a current Ph.D. project at the University of Copenhagen, Denmark. Diagenetically formed pyrite is a common constituent of marine shales and the study of pyrite morphotypes has previously been successful from thermalli immature parts of elucidating depositional environment and thermal effects in the Alum Shale Formation of Scandinavia (Nielsen 1996; Nielsen et al. 1998). The present paper describes the preliminary results of a similar study on pyrite from thermally immature parts of the Ravnefjeld Formation which, combined with the study of textures of base metal sulphides in the Wegener Halvø area (Fig. 1), may provide an important step in the evaluation of the presence or absence of early thermal activity on (or below) the Upper Permian sea floor.

Sequence stratigraphy of source and reservoir rocks in the Upper Permian and Jurassic of Jameson Land, East Greenland

1998 ◽  
pp. 43-54 ◽  
Author(s):  
Lars Stemmerik ◽  
Gregers Dam ◽  
Nanna Noe-Nygaard ◽  
Stefan Piasecki ◽  
Finn Surlyk
Keyword(s):  
Sequence Stratigraphy ◽  
Middle Jurassic ◽  
Sedimentary Basins ◽  
Upper Jurassic ◽  
Oil Field ◽  
Source Rocks ◽  
Upper Permian ◽  
Shallow Marine ◽  
East Greenland ◽  
Reservoir Rocks

NOTE: This article was published in a former series of GEUS Bulletin. Please use the original series name when citing this article, for example: Stemmerik, L., Dam, G., Noe-Nygaard, N., Piasecki, S., & Surlyk, F. (1998). Sequence stratigraphy of source and reservoir rocks in the Upper Permian and Jurassic of Jameson Land, East Greenland. Geology of Greenland Survey Bulletin, 180, 43-54. https://doi.org/10.34194/ggub.v180.5085 _______________ Approximately half of the hydrocarbons discovered in the North Atlantic petroleum provinces are found in sandstones of latest Triassic – Jurassic age with the Middle Jurassic Brent Group, and its correlatives, being the economically most important reservoir unit accounting for approximately 25% of the reserves. Hydrocarbons in these reservoirs are generated mainly from the Upper Jurassic Kimmeridge Clay and its correlatives with additional contributions from Middle Jurassic coal, Lower Jurassic marine shales and Devonian lacustrine shales. Equivalents to these deeply buried rocks crop out in the well-exposed sedimentary basins of East Greenland where more detailed studies are possible and these basins are frequently used for analogue studies (Fig. 1). Investigations in East Greenland have documented four major organic-rich shale units which are potential source rocks for hydrocarbons. They include marine shales of the Upper Permian Ravnefjeld Formation (Fig. 2), the Middle Jurassic Sortehat Formation and the Upper Jurassic Hareelv Formation (Fig. 4) and lacustrine shales of the uppermost Triassic – lowermost Jurassic Kap Stewart Group (Fig. 3; Surlyk et al. 1986b; Dam & Christiansen 1990; Christiansen et al. 1992, 1993; Dam et al. 1995; Krabbe 1996). Potential reservoir units include Upper Permian shallow marine platform and build-up carbonates of the Wegener Halvø Formation, lacustrine sandstones of the Rhaetian–Sinemurian Kap Stewart Group and marine sandstones of the Pliensbachian–Aalenian Neill Klinter Group, the Upper Bajocian – Callovian Pelion Formation and Upper Oxfordian – Kimmeridgian Hareelv Formation (Figs 2–4; Christiansen et al. 1992). The Jurassic sandstones of Jameson Land are well known as excellent analogues for hydrocarbon reservoirs in the northern North Sea and offshore mid-Norway. The best documented examples are the turbidite sands of the Hareelv Formation as an analogue for the Magnus oil field and the many Paleogene oil and gas fields, the shallow marine Pelion Formation as an analogue for the Brent Group in the Viking Graben and correlative Garn Group of the Norwegian Shelf, the Neill Klinter Group as an analogue for the Tilje, Ror, Ile and Not Formations and the Kap Stewart Group for the Åre Formation (Surlyk 1987, 1991; Dam & Surlyk 1995; Dam et al. 1995; Surlyk & Noe-Nygaard 1995; Engkilde & Surlyk in press). The presence of pre-Late Jurassic source rocks in Jameson Land suggests the presence of correlative source rocks offshore mid-Norway where the Upper Jurassic source rocks are not sufficiently deeply buried to generate hydrocarbons. The Upper Permian Ravnefjeld Formation in particular provides a useful source rock analogue both there and in more distant areas such as the Barents Sea. The present paper is a summary of a research project supported by the Danish Ministry of Environment and Energy (Piasecki et al. 1994). The aim of the project is to improve our understanding of the distribution of source and reservoir rocks by the application of sequence stratigraphy to the basin analysis. We have focused on the Upper Permian and uppermost Triassic– Jurassic successions where the presence of source and reservoir rocks are well documented from previous studies. Field work during the summer of 1993 included biostratigraphic, sedimentological and sequence stratigraphic studies of selected time slices and was supplemented by drilling of 11 shallow cores (Piasecki et al. 1994). The results so far arising from this work are collected in Piasecki et al. (1997), and the present summary highlights the petroleum-related implications.

Late Permian carbonate concretions in the marine siliciclastic sediments of the Ravnefjeld Formation, East Greenland

2002 ◽  
pp. 126-132
Author(s):  
Jesper Kresten Nielsen ◽  
Nils-Martin Hanken
Keyword(s):  
Mineral Resources ◽  
Sedimentary Basins ◽  
Sedimentary Facies ◽  
Carbonate Reservoir ◽  
Upper Permian ◽  
Late Permian ◽  
East Greenland ◽  
Reservoir Rocks ◽  
Carbonate Concretions ◽  
Siliciclastic Sediments

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.

scholarly journals Characteristics of Mineralogy, Lithofacies of Fine-Grained Sediments and Their Relationship with Sedimentary Environment: Example from the Upper Permian Longtan Formation in the Sichuan Basin

Energies ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3662
Author(s):  
Hongzhi Yang ◽  
Liangbiao Lin ◽  
Liqing Chen ◽  
Yu Yu ◽  
Du Li ◽  
...  
Keyword(s):  
Mineral Composition ◽  
Sichuan Basin ◽  
Sedimentary Environment ◽  
Organic Matter Content ◽  
Upper Permian ◽  
Carbonaceous Shale ◽  
Carbonate Minerals ◽  
Thin Sections ◽  
Terrestrial Input ◽  
The Sichuan Basin

The Longtan Formation of the Upper Permian in the Sichuan Basin has become a significant target for shale gas exploration in recent years. Multiple methods, including outcrop observations, thin sections, total organic matter content, X-ray diffraction and scanning electron microscopy were used to investigate the mineralogy, shale lithofacies assemblages and their relationships with the deposition environment. The mineral composition of the Longtan Formation has strong mineral heterogeneity. The TOC values of the Longtan Formation have a wide distribution range from 0.07% to 74.67% with an average value of 5.73%. Four types of shale lithofacies assemblages of the Longtan Formation could be distinguished, as clayey mudstone (CLS), carbonaceous shale (CAS), siliceous shale (SS) and mixed shale (MS) on the basis of mineral compositions. The TOC values of various types of shale lithofacies assemblages in the Longtan Formation varied widely. The shore swamp of the Longtan Formation is most influenced by the terrestrial input and mainly develops CLS and MS. The tidal flat is influenced by the terrestrial input and can also deposit carbonate minerals, developing CLS, CAS and MS. The shallow water melanged accumulation shelf develops CAS and MS, dominated by clay and carbonate minerals. The deep water miscible shelf develops CLS and SS, whose mineral composition is similar to that of the shore swamp, but the quartz minerals are mainly formed by chemical and biological reactions, which are related to the Permian global chert event. The depositional environment of the Longtan Formation controls the shale mineral assemblage of the Longtan Formation and also influences the TOC content.

Physiography, Ecology, and Sediments of Two Bermuda Patch Reefs

1971 ◽  
Vol 79 (6) ◽  
pp. 647-668 ◽  
Author(s):  
Peter Garrett ◽  
Donald L. Smith ◽  
Augustus O. Wilson ◽  
David Patriquin
Keyword(s):  
Patch Reefs
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