scholarly journals Stratigraphy and sedimentology of Upper Ordovician to Lower Devonian clastic formations, Cañon Fiord region, Ellesmere Island

1973 ◽  
Author(s):  
H P Trettin
Keyword(s):  
Lower Devonian ◽  
Ellesmere Island ◽  
Upper Ordovician

scholarly journals Chrono-, litho- and conodont bio-stratigraphy of the Rauchkofel Boden Section (Upper Ordovician – Lower Devonian), Carnic Alps, Austria

2017 ◽  
Vol 50 (4) ◽  
pp. 445-469 ◽  
Author(s):  
Hans Peter Schönlaub ◽  
Carlo Corradini ◽  
Maria G. Corriga ◽  
Annalisa Ferretti
Keyword(s):  
Lower Devonian ◽  
Upper Ordovician ◽  
Carnic Alps

Chronometric calibration of mid-Ordovician to Tournaisian conodont zones: a compilation from recent graphic-correlation and isotope studies

1992 ◽  
Vol 129 (6) ◽  
pp. 709-721 ◽  
Author(s):  
Barry G. Fordham
Keyword(s):  
High Resolution ◽  
High Precision ◽  
Time Scale ◽  
Lower Devonian ◽  
New South ◽  
Upper Ordovician ◽  
South Wales ◽  
Isotope Studies ◽  
Stratotype Section ◽  
Upper Silurian

AbstractThree available graphic-correlation analyses are used to calibrate mid-Palaeozoic conodont zonations: Sweet's scheme for the mid- to Upper Ordovician; Kleffner's for the mid- to Upper Silurian; and Murphy & Berry's for the lower and middle Lower Devonian. The scheme of Sweet is scaled by applying the high-precision U-Pb zircon date of Tucker and others for the Rocklandian and linked with that of Kleffner by scaling the graptolite sequence of the Ordovician-Silurian global stratotype section to fit two similarly derived dates from this sequence. The top of Kleffner's scheme, all of Murphy & Berry's, as well as standard zones to the Frasnian are calibrated by using tie-points of the latest Cambridge-BP time-scale (GTS 89). However, the recent microbeam zircon date by Claoué-Long and others for the Hasselbachtal Devonian-Carboniferous auxiliary stratotype is used to calibrate the standard Famennian zones. Also the similarly derived but preliminary determination reported by Roberts and others from the Isismurra Formation of New South Wales is tentatively taken as the top of the Tournaisian and so used to calibrate Tournaisian zones. Despite the considerable extrapolation required to compile these schemes and their inherent errors, the resultant time-scale closely agrees with other dates of Tucker and others from the Llanvirn as well as the GTS 89 Homerian-Gorstian tie-point. This suggests that stratigraphic methods can be usefully applied to geochronometry. The Llandovery appears to have lasted longer (16 m. y.) than usually envisaged and the Ordovician-Silurian boundary may need to be lowered to approximately 443.5 Ma. Certainly, chrons varied widely in duration and further stratigraphic studies to estimate their relative durations as well as high-resolution dating for their calibration will be crucial to more accurate biochronometries.

Biostratigraphic significance of lower Paleozoic microfaunas from eastern Canada

2004 ◽  
Vol 41 (5) ◽  
pp. 489-505 ◽  
Author(s):  
Esther Asselin ◽  
Aïcha Achab ◽  
Azzedine Soufiane
Keyword(s):  
New Brunswick ◽  
Lower Devonian ◽  
Head Group ◽  
Upper Ordovician ◽  
Eastern Canada ◽  
Lower Paleozoic ◽  
Anticosti Island ◽  
Gaspe Peninsula ◽  
Gaspé Peninsula ◽  
Mapping Program

Chitinozoan studies recently carried out in the “Appalachian Forelands and St. Lawrence Platform” National Geoscience Mapping Program (NATMAP) project have confirmed the regional biostratigraphic value of a number of chitinozoan species and led to a better documentation of their stratigraphic and geographic distribution in eastern Canada. The typical Darriwilian microfaunas first described from the Table Head Group of western Newfoundland and containing Conochitina chydaea are now recognised in the Rivière Ouelle Formation at Les Méchins, Gaspé Peninsula. In the Upper Ordovician successions of the St. Lawrence Platform at Neuville and in the Charlevoix area, Quebec, Conochitina primitiva is indicative of the multidens–pre-americanus graptolite zonal range, Hercochitina duplicitas of the americanus Zone, and Hercochitina spinetum and Acanthochitina cancellata characterize the ruedemanni – lower spiniferus zonal interval. The occurrence of Cyathochitina vaurealensis and Hercochitina crickmayi in turbidite deposits of the Grog Brook Group of northwestern New Brunswick confirms the minimal facies dependence of these two Richmondian index species. Eisenackitina dolioliformis, characteristic of the late Aeronian and Telychian successions of Arctic Canada, Gaspé Peninsula, and Anticosti Island, is now recognised in samples from the Upsalquitch Formation of northwestern New Brunswick and the Cabano Formation of the Rimouski area in Quebec. The palynological data from Devonian successions of the Matapedia Valley, the Rimouski area, and the Beauce – Eastern Townships region show that the succession of Lower Devonian chitinozoan assemblages of the Forillon Peninsula based on short-ranging species can be used in establishing regional correlations in the Gaspé Belt.

scholarly journals Upper Neoproterozoic to Lower Devonian stratigraphy of northeast Ellesmere Island

2008 ◽  
Author(s):  
K Dewing ◽  
U Mayr ◽  
J C Harrison ◽  
T de Freitas
Keyword(s):  
Lower Devonian ◽  
Ellesmere Island

scholarly journals Upper Neoproterozoic to Lower Devonian stratigraphy of northeast Ellesmere Island

2009 ◽  
Author(s):  
K Dewing ◽  
U Mayr ◽  
J C Harrison ◽  
T de Freitas
Keyword(s):  
Lower Devonian ◽  
Ellesmere Island
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