Results 141 to 150 of about 1,952 (183)

Upper Ordovician Shales in Central Kansas

AAPG Bulletin, 1947
Shales approximately equivalent in age to Maquoketa beds in Iowa and to Sylvan strata in Oklahoma form the topmost Ordovician over much of central Kansas. They normally consist of two members: (1) an upper dolomitic gray shale, which is siliceous and cherty in some areas, and (2) a lower soft flaky shale.
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Mottled Upper Ordovician Carbonates in Northwest Georgia

SEPM Journal of Sedimentary Research, 1975
Mottled red and gray-green, silty limestones and calcareous siltstones occur in the Sequatchie Formation (Upper Ordovician) near Ringgold, Georgia. X-ray diffraction and optical methods show that the red mottles are due to the presence of diagenetic hematite, which was formed by oxidation of iron expelled from detrital chlorite.
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JAWED POLYCHAETES FROM THE UPPER SYLVAN SHALE (UPPER ORDOVICIAN), OKLAHOMA, USA

Journal of Paleontology, 2005
A jawed polychaete fauna from the upper 30 m of the Upper Ordovician Sylvan Shale (Richmondian, Ashgill) of Oklahoma is described, based on recovered scolecodonts (polychaete jaws). The fauna includes members of six families: Paulinitidae, Rampho- prionidae, Polychaetaspidae, Atraktoprionidae, Hadoprionidae, and Kalloprionidae.
MATS E. ERIKSSON, STEPHEN A. LESLIE, CLAES F. BERGMAN   +2 more
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Lower Caradocian (upper Ordovician) Chitinozoa from North Wales

Review of Palaeobotany and Palynology, 1971
Abstract Glanrafon (Ordovician) chitinozoan assemblages are described from the River Glaslyn area of North Wales. The rocks from which these Chitinozoa were collected have been metamorphosed to slate grade. The Chitinozoa are used to date the succesion as Lower Caradocian and to correlate within the area. The fauna is compared with material described
Keith Atkinson, Rosa Lesley Moy
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Upper Ordovician stratigraphy of Southampton Island, Northwest Territories

Canadian Journal of Earth Sciences, 1991
The middle to late Caradoc Bad Cache Rapids Formation of Southampton Island consists of three "members": a locally present thin siliciclastic unit, overlain by a highly fossiliferous wackestone, capped by a mudstone, all deposited in a broad, shallow shelf setting.
Keith Dewing, Paul Copper
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Ostracods from the Upper Ordovician Borenshult fauna, Sweden

GFF, 2007
Abstract The Borenshult locality was a temporarily exposed, richly fossiliferous locality with the Hirnantia fauna. It yielded a rich and diverse ostracod assemblage, the Harpabollia harparum association. This association differs from other Upper Ordovician and Llandoverian ostracod faunas of Baltoscandia.
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Upper Ordovician Glaciation in Northwest Africa? Discussion

Geological Society of America Bulletin, 1971
Faunal, paleomagnetic, and sedimentological arguments that claim to show the existence of a continental ice sheet in northwest Africa during the Ordovician and Silurian are questionable. Neither the fauna nor the relevant pole positions necessitate the presence of land ice.
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Upper Ordovician Bryozoa from Sardinia.

1990
This paper presents the taxonomical descriptions of Upper Caradocian to Ashgillian bryozoans recovered from different localities from SW Sardinia and from one locality (Mulargia lake) from SE Sardinia. The investigated fauna belongs to 4 bryozoan orders: the Trepostomata, the Cystoporata, the Cryptostomata and the extant order Tubuliporata.
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Dolomitization in Upper Red River Formation (Upper Ordovician), North Dakota: ABSTRACT

AAPG Bulletin, 1979
The upper Red River Formation (Upper Ordovician) in North Dakota contains four porosity zones which are divided into two different styles of syndepositional dolomitization. The "D" zone is the base of the upper Red River and comprises two regularly interbedded, primary facies: mottled, partially dolomitized, porous mudstone and wackestone overlain by ...
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Upper Middle Ordovician - (?)lower Upper Ordovician conodonts from offshore Kaarehamn wind park, north-east Öland, Sweden.

2016
A new collection of upper Middle Ordovician (Darriwilian) - perhaps extending into lower Upper Ordovician - conodonts is taken from the offshore P4 well (56o58’47.9’’N, 17o1’11.9’’E). Currently 17 genera and 23 species have been identified, comprising the nominate taxa Pygodus serra, Eoplacognathus robustus, Eoplacognathus lindstroemi and Pygodus ...
Ficini F., BAGNOLI, GABRIELLA, Stouge S.
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