scholarly journals Brachiopods [schizophoria, strophodonta (strophodonta), nervostrophia, eostrophalosia and devonoproductus] from the lower upper devonian Waterways formation of northeastern Alberta

1983 ◽  
Author(s):  
A W Norris
Keyword(s):  
Upper Devonian ◽  
Lower Upper ◽  
Northeastern Alberta

Review of the Devonian camerate crinoid Bogotacrinus scheibei Schmidt from Colombia

1987 ◽  
Vol 61 (4) ◽  
pp. 750-757 ◽  
Author(s):  
George C. Mcintosh
Keyword(s):  
North America ◽  
Western Europe ◽  
Lower Devonian ◽  
Appalachian Basin ◽  
Upper Devonian ◽  
Eastern North America ◽  
Late Devonian ◽  
Early Devonian ◽  
Lower Upper

Two recently collected specimens of Bogotacrinus scheibei Schmidt, 1937, from the Devonian (Emsian–Eifelian) Floresta Formation of Colombia reveal that Bogotacrinus is a dicyclic camerate crinoid genus closely related to Pterinocrinus Goldring, 1923 (Lower–Upper Devonian of eastern North America and western Europe), and Ampurocrinus McIntosh, 1981 (Lower Devonian of Bolivia). The new diplobathrid camerate crinoid family Pterinocrinidae, characterized by species with low conical dicyclic cups and rami composed of compound, bipinnulate brachials, is herein proposed to accommodate these three genera. This family originated in western Europe and migrated into the Malvinokaffric and southern Eastern Americas Realms during the Early Devonian and into the northeastern Appalachian Basin by the Late Devonian.

A Unique Dolomite Reservoir: The Upper Devonian Grosmont Formation in Northeastern Alberta, Canada

AAPG Bulletin ◽  
1992 ◽  
Vol 76 ◽  
Author(s):  
HUEBSCHER, H., E. DEMBICKI, and H.
Keyword(s):  
Upper Devonian ◽  
Northeastern Alberta

Contribution a l'etude du Couvinien dans le bassin de Fort-de-Polignac (Sahara)

1961 ◽  
Vol S7-III (5) ◽  
pp. 449-456 ◽  
Author(s):  
Jean Chaumeau ◽  
Philippe Legrand ◽  
Alzine Renaud
Keyword(s):  
Middle Devonian ◽  
Lower Devonian ◽  
Upper Devonian ◽  
Lower Upper ◽  
Shaly Sandstone ◽  
Lateral Variations

Abstract The contact of lower Devonian sandstone and shaly sandstone with middle Devonian shaly limestone is exposed at several points in the vicinity of Fort-de-Polignac in the Sahara. The lower Devonian beds show large lateral variations. Instead of the Givetian (upper middle Devonian) transgressing the lower Devonian, as previously supposed, the transgression began in the center of the basin in the Couvinian or Eifelian, i.e., lower middle Devonian, spread progressively eastward and westward, and did not reach the Oued Samene area until upper Couvinian. The submergence of the lower part of Tihemboka, west of In Akaouet, did not occur until Frasnian (lower upper Devonian).

The Upper Devonian fish locality of Miguasha, Quebec, Canada

1992 ◽  
Vol 6 ◽  
pp. 262-262
Author(s):  
Hans-Peter Schultze
Keyword(s):  
Fish Fauna ◽  
Detailed Comparison ◽  
Upper Devonian ◽  
Single Plane ◽  
Lower Upper ◽  
Plant Fossils ◽  
Marine Deposits ◽  
Dermal Bone ◽  
Freshwater Bodies ◽  
The Baltic

At Miguasha, Québec (earlier referred to as Scaumenac Bay), the Escuminac Formation, lowermost Upper Devonian, yields an abundant and diverse fish fauna and flora. Both vertebrates and plant fossils from the locality are reknowned throughout the world. The excellent preservation, including that of endocranial anatomy, enabled Jarvik to describe and illustrate fine anatomical details of the osteolepiform Eusthenopteron. That gives the wrong impression that Miguasha is throughout the Escuminac Formation an outstanding Conservat Fossil-Lagerstätte.The cliffs at Miguasha bear fishes throughout the approximately 120 m thick Escuminac Formation. The lithology of the sediments changes throughout the sequence. Close to the base of the formation, acanthodians and anaspid-like agnathans occur in laminites, sometimes hundreds on one horizon. In these laminites, soft tissue preservation may occur (anapsid-like agnathans), and diagenetic transformations of acanthodians into organic substance led to misinterprations and recognition of the “larval chordate Scaumenella.” Most common within the sequence are limy concretions with different fish fossils, most commonly Bothriolepis. Three-dimensionally preserved fishes occur within the sandstone-siltstones and sometimes within the concretions. In all these cases, dermal bone is preserved, and in few cases chondral bone too, as in Eusthenopteron. One can characterize these fossiliferous sections of the Escuminac Formation as Concentration Fossil-Lagerstätte, whereas the laminites are Conservat Fossil-Lagerstätten.The depositional environment was previously interpreted as an intermontaneous basin, based on tectonic and paleogeographic position. More recent paleogeographic reconstructions show a connection with Scottish deposits and to marine deposits in the present day North Sea. The lack of invertebrates and of marine plant remains, and the occurrence of vertebrates in other localities were used as additional indicators for freshwater deposition.The sedimentological features are ambiguous, the turbidites, such as those found at Miguasha, can occur in marine or large freshwater bodies. Conchostracans occur, sometimes in the thousands on a single plane, in the basal part of the Escuminac Formation. They occur today in freshwater or brackish environments; the same species as the one in the Escuminac Formation is reported from lower Upper Devonian marine deposits in the Baltic (Koknese, Latvia). A detailed comparison of the fish fauna with other lower Upper Devonian fish faunas indicates a coastal marine environment. That is supported by rare trace fossils and by different chemical analyses of the sediments and 87S/86S analysis of Bothriolepis bones.In conclusion, earlier interpretations of the paleogeographic position of the Escuminac Formation at Miguasha and chemical and faunal indicators contradict each other in the interpretation of the paleoenvironment of the formation.

Proximal Continental Rhythmic Sequences in the Genesee Group (Lower Upper Devonian) of Southeastern New York

1968 ◽  
pp. 109-126 ◽  
Author(s):  
Peter J. R. Buttner
Keyword(s):  
New York ◽  
Upper Devonian ◽  
Lower Upper

Revised Correlations of Lower Upper Devonian Rocks in Western and Central New York

AAPG Bulletin ◽  
1959 ◽  
Vol 43 ◽  
Author(s):  
Wallace De Witt, Jr. (2), George W.
Keyword(s):  
New York ◽  
Upper Devonian ◽  
Lower Upper ◽  
Central New York
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