Late Ordovician brachiopods Rafinesquina lata Whiteaves, 1896 and Kjaerina hartae n.sp. from southern Manitoba and the Hudson Bay Lowlands

1995 ◽  
Vol 32 (8) ◽  
pp. 1255-1266 ◽  
Author(s):  
Jisuo Jin ◽  
W. G. E. Caldwell ◽  
B. S. Norford
Keyword(s):  
Depositional Environment ◽  
Late Ordovician ◽  
Red River ◽  
Warm Water ◽  
Ventral Valve ◽  
Hudson Bay ◽  
Hudson Bay Lowlands ◽  
Cardinal Process

Examination of the Late Ordovician strophomenid brachiopod Rafinesquina lata Whiteaves, 1896 from the Selkirk Member of the Red River Formation of southern Manitoba reveals that the two syntypes actually represent two genera and two species, Oepikina lata and Kjaerina hartae n.sp. Specimens typically described as Rafinesquina lata by Whiteaves are large, thick-shelled, strongly but evenly concavo-convex, with randomly spaced, fine, concentric growth lamellae and a high ventral interarea. Affinity of the species to Oepikina lies in its unequal parvicostellae of the ventral valve, conspicuous dorsal peripheral rim, robust cardinal process, and strong lateral trans-muscle septa. Kjaerina hartae is easily distinguished from O. lata by its strongly geniculate and less massive shell, a much lower ventral interarea, prominent concentric rugae, and, internally, considerably weaker trans-muscle septa. The shells of O. lata and K. hartae are unusually large and suggest an open, shallow- and warm-water, subtidal depositional environment for the original sediments of the Selkirk Member of the Red River Formation. Common occurrences of K. hartae in the upper Portage Chute and Surprise Creek formations (Bad Cache Rapids Group) of the Hudson Bay Lowlands, together with other brachiopods and other groups of fossils, support the concept that the epicontinental seas once covering the Hudson Platform and the Williston Platform were connected during Late Ordovician (Maysvillian) time.

scholarly journals Late Ordovician brachiopods and biostratigraphy of the Hudson Bay Lowlands, northern Manitoba and Ontario

1997 ◽  
Author(s):  
J Jin ◽  
W G E Caldwell ◽  
B S Norford
Keyword(s):  
Late Ordovician ◽  
Hudson Bay ◽  
Hudson Bay Lowlands

Late Ordovician brachiopods Rafinesquina lata Whiteaves, 1896 and Kjaerina hartae n.sp. from southern Manitoba and the Hudson Bay Lowlands

1995 ◽  
Vol 32 (12) ◽  
pp. 2168-2168
Author(s):  
Jisuo Jin ◽  
W. G. E. Caldwell ◽  
B. S. Norford
Keyword(s):  
Late Ordovician ◽  
Hudson Bay ◽  
Hudson Bay Lowlands

Evolution of the late Ordovician orthid brachiopod Gnamptorhynchos Jin, 1989 from Platystrophia King, 1850, in North America

2000 ◽  
Vol 74 (6) ◽  
pp. 983-991
Author(s):  
Jisuo Jin ◽  
Renbin Zhan
Keyword(s):  
New Species ◽  
North America ◽  
Mass Extinction ◽  
Type Species ◽  
Late Ordovician ◽  
Red River ◽  
Lower Range ◽  
Cardinal Process ◽  
Senior Synonym ◽  
Morphological Intermediate

Gnamptorhynchos, a rhynchonellid-like orthid brachiopod, evolved from Platystrophia in Maysvillian (early Ashgill) time, and survived both the end-Richmondian and end-Hirnantian episodes of the latest Ordovician mass extinction. The name of the type species of Gnamptorhynchos, G. inversum Jin, 1989, is rejected and replaced by Gnamptorhynchos globatum (Twenhofel, 1928), which is a senior synonym. Gnamptorhynchos manitobensis new species is described here from the Selkirk Member (Maysvillian) of the Red River Formation, southern Manitoba. The new species is characterized by a transversely extended, strongly biconvex to globular shell with prominent umbones, relatively numerous costae and a notothyrial cavity supported dorsally by a short median ridge. It constituted part of a Late Ordovician epicontinental fauna that once spread widely in shallow, equatorial seas of North America. The new species is a morphological intermediate between Platystrophia and Gnamptorhynchos, with Platystrophia-like interareas, hingeline, and cardinal process, but Gnamptorhynchos-like shell posterior and notothyrial platform. Previously, Gnamptorhynchos was known from Hirnantian to mid-Aeronian rocks. The new species extends the lower range of the genus to Maysvillian.

Constraining the age of the last interglacial–glacial transition in the Hudson Bay lowlands (Canada) using U–Th dating of buried wood

2012 ◽  
Vol 7 ◽  
pp. 37-47 ◽  
Author(s):  
G. Allard ◽  
M. Roy ◽  
B. Ghaleb ◽  
P.J.H. Richard ◽  
A.C. Larouche ◽  
...  
Keyword(s):  
Hudson Bay ◽  
Last Interglacial ◽  
Hudson Bay Lowlands

scholarly journals Bird trends from long-term observation data at sites in the Hudson Bay Lowlands

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Rodney W. Brook ◽  
Lisa A. Pollock ◽  
Kenneth F. Abraham ◽  
Glen S. Brown
Keyword(s):  
Hudson Bay ◽  
Observation Data ◽  
Hudson Bay Lowlands ◽  
Long Term Observation

scholarly journals Upper Ordovician graptolites from the Cape Phillips Formation, Canadian Arctic Islands

1987 ◽  
Vol 35 ◽  
pp. 191-202
Author(s):  
M. J. Melchin
Keyword(s):  
Great Britain ◽  
Shallow Water ◽  
Depositional Environment ◽  
Canadian Arctic ◽  
Late Ordovician ◽  
Outer Shelf ◽  
Upper Ordovician ◽  
The World ◽  
Cape Phillips Formation ◽  
Varying Length

Ashgill age graptolites have been collected from seven sections of the Cape Phillips Formation across most of its outcrop belt. The earliest graptolite zone recognisable is that of Orthograptus fastigatus. It is correla­ted with the Dicellograptus ornatus · Zone of the northern Canadian Cordilllera and the Dicellograptus complexus Subzone of the Dicel/ograptus anceps Zone of Great Britain although no dicellograptids have been found at any of the present sections. The overlying zone is that of Paraorthograptus pacificus, an ea­sily recognisable zone around much of the world. Graptolites of the C/imacograptus extraordinarius and Glyptograptus persculptus zones appear to be en­tirely absent from this formation. This is attributed to the Late Ordovician glaciation which has induced regression and submarine erosion in many areas worldwide. The earliest recognisable Silurian zone varies from section to section due to buried or barren intervals and/or hiatuses of varying length. The Parakidograptus acuminatus Zone has been recognised at only one section. At the others, the Atavograptus atavus, the Lagarograptus acinaces-Coronograptus gregarius, the Monograptus convolutus or the Monograptus spiralis Zone (s.1.) are the earliest recognisable Silurian fau­nas. Relatively low fauna! diversities in the Ashgill and lowest Llandovery portion of the section and the to­tal lack of dicellograptids are interpreted to be due to relatively shallow water, outer shelf or carbonate ramp depositional environment.

scholarly journals Constraining the Late Pleistocene history of the Laurentide Ice Sheet by dating the Missinaibi Formation, Hudson Bay Lowlands, Canada

2016 ◽  
Vol 146 ◽  
pp. 288-299 ◽  
Author(s):  
April S. Dalton ◽  
Sarah A. Finkelstein ◽  
Peter J. Barnett ◽  
Steven L. Forman
Keyword(s):  
Late Pleistocene ◽  
Ice Sheet ◽  
Laurentide Ice Sheet ◽  
Hudson Bay ◽  
Hudson Bay Lowlands ◽  
History Of

scholarly journals Late Pleistocene chronology, palaeoecology and stratigraphy at a suite of sites along the Albany River, Hudson Bay Lowlands, Canada

2018 ◽  
Vol 492 ◽  
pp. 50-63 ◽  
Author(s):  
April S. Dalton ◽  
Sarah A. Finkelstein ◽  
Peter J. Barnett ◽  
Minna Väliranta ◽  
Steven L. Forman
Keyword(s):  
Late Pleistocene ◽  
Hudson Bay ◽  
Hudson Bay Lowlands
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