The Ibexian Series (Lower Ordovician), a replacement for "Canadian Series" in North American chronostratigraphy

1993 ◽  
Author(s):  
R.J. Ross ◽  
L.F. Hintze ◽  
Raymond L. Ethington ◽  
J.F. Miller ◽  
M.E. Taylor ◽  
...  
Keyword(s):  
North American ◽  
Lower Ordovician

The Lower Ordovician Brachiopod Syntrophla sp., cf. S. arethusa (Billings 1862) from South Catcher Pond, Northeastern Newfoundland

1973 ◽  
Vol 10 (3) ◽  
pp. 427-430 ◽  
Author(s):  
A. J. Boucot
Keyword(s):  
North American ◽  
Volcanic Rocks ◽  
Lower Ordovician ◽  
First Time

The Lower Ordovician North American Province brachiopod genus Syntrophia is recognized for the first time from northern Newfoundland. It occurs together with other Lower Ordovician fossils (trilobites and conodonts) in a limestone lens interbedded with volcanic rocks that may belong to the Lush's Bight Group.

scholarly journals Summary account of the Lower Ordovician (Arenig) graptolite biostratigraphy of the Cow Head Group, western Newfoundland

1987 ◽  
Vol 35 ◽  
pp. 259-270
Author(s):  
S. Henry Williams ◽  
Robert K. Stevens
Keyword(s):  
Continental Margin ◽  
North American ◽  
Repeated Exposure ◽  
Head Group ◽  
Middle Cambrian ◽  
Lower Ordovician ◽  
Evolutionary Step ◽  
American Standard ◽  
Lower Slope

The Cow Head Group is an allochthonous sequence of Middle Cambrian to late Arenig sedimentary brec­cias, limestones and shales deposited in a deep lower slope environment close to a continental margin. Im­bricate thrusting has resulted in repeated exposure of laterally equivalent "proximal" to "distal" facies which may be correlated using graptolitic control in the interbeds. "Proximal" sections are characterised by massive, coarse breccias with interbedded limestones and green/dark grey shales. More distal ex­posures have fewer and thinner breccias and limestones, while the green/grey shales are replaced pro­gressively by red, non-graptolitic ones. Although the succession is by no mean unbroken or complete, it furnishes one of the best and most con­tinuously graptolitic sections through the Arenig. A new zonal scheme is erected for the Cow Head Group, which could prove suitable as a new North American standard. Furthermore, several limestones and siliceous shales have yielded exquisitely preserved isolated material, permitting integration of fine growth detail with complete flattened specimens. With the exception of the uppermost Arenig U. austrodentatus Zone, Arenig graptoloids possess a pro­sicular origin for thl1• The earliest graptoloids with a metasicular origin for the first theca appear in this zone, including Undulograptus, Cryptograptus and Paraglossograptus. This interval, equivalent to Dai of the Australasian scheme, therefore represents a hitherto unrecorded major evolutionary step in graptolite evolution.

Jujuyaspis borealis and associated trilobites and conodonts from the Lower Ordovician of Texas and Utah

1987 ◽  
Vol 61 (1) ◽  
pp. 112-121 ◽  
Author(s):  
James H. Stitt ◽  
James F. Miller
Keyword(s):  
United States ◽  
South America ◽  
North American ◽  
The United States ◽  
International Agreement ◽  
Lower Ordovician ◽  
Central Texas ◽  
North And South America ◽  
First Time ◽  
North And South

Jujuyaspis borealis is reported from earliest Ordovician (North American usage) limestones in central Texas and western Utah, the first time this species has been recognized in the United States. Jujuyaspis is a widespread olenid trilobite that occurs near the base of the Tremadoc Series in a variety of lithologies in North and South America, Europe, and Asia. When international agreement is reached on the exact horizon at or near the base of the Tremadoc Series that is to be used as the Cambrian–Ordovician boundary, Jujuyaspis will likely prove to be a very useful taxon for recognition of the boundary interval.

Early Ordovician Dounans Limestone fauna, Highland Border Complex, Scotland

1985 ◽  
Vol 76 (4) ◽  
pp. 481-513 ◽  
Author(s):  
J. Keith Ingham ◽  
Gordon B. Curry ◽  
Alwyn Williams
Keyword(s):  
North American ◽  
Red Sandstone ◽  
Middle Ordovician ◽  
Early Ordovician ◽  
Incertae Sedis ◽  
Lower Ordovician ◽  
Carbonate Sequence

ABSTRACTA diverse, but sparsely distributed silicified fauna of over 30 taxa has been recovered from 7·5 tonnes of acid-etched Lower Ordovician Dounans Limestone from the Highland Border Complex, near Aberfoyle. The 13 trilobite taxa obtained include 3 new formally named species: Distazeris adoceta, Punka aetholiciocorus and Ischyrotoma stubblefieldi. Other elements, representing Carolinites, Illaenus, Goniotelina, Sycophantia, Kawina, Heliomeroides, Strotactinus, Ectenonotus, Ceratocephala and an indeterminate bathyurelline are described under open nomenclature although at least 4 are also probably new and 2 more may be conspecific with previously described species. The brachiopods include representatives of Archaeorthis, Nothorthis, Orthidium, ?Camerella, Idiostrophia, Orthambonites and 4 other indeterminate stocks. Gastropods tentatively assigned to Murchisonia, Subulites, Straparollina, Maclurites and Cyrtodiscus are described, as are bryozoans, an orthocone, crinoids, and Incertae sedis.This profoundly North American fauna is Late Canadian ( = mid Arenig) in age and equates with the Cassinian Stage: it is key evidence in showing that the Highland Border rocks are not part of the Dalradian Supergroup whose earliest deformations and metamorphism predate the Ordovician. The field relationships of the limestone, together with evidence from derived clasts in Middle Ordovician and Devonian sequences near Girvan in SW Scotland and at Stonehaven in eastern Scotland suggest that it forms part of a widespread sub-Old Red Sandstone carbonate sequence of Early Ordovician age beneath the northern Midland Valley.

Adaptation of the Connected Speech Test: Rerecording and Passage Equivalency

2020 ◽  
Vol 29 (2) ◽  
pp. 259-264 ◽  
Author(s):  
Hasan K. Saleh ◽  
Paula Folkeard ◽  
Ewan Macpherson ◽  
Susan Scollie
Keyword(s):  
Speech Perception ◽  
North American ◽  
First Language ◽  
Intraclass Correlation ◽  
Normal Hearing ◽  
Connected Speech ◽  
Internal Reliability ◽  
Speech Test ◽  
The Mean ◽  
Unit Standard

Purpose The original Connected Speech Test (CST; Cox et al., 1987) is a well-regarded and often utilized speech perception test. The aim of this study was to develop a new version of the CST using a neutral North American accent and to assess the use of this updated CST on participants with normal hearing. Method A female English speaker was recruited to read the original CST passages, which were recorded as the new CST stimuli. A study was designed to assess the newly recorded CST passages' equivalence and conduct normalization. The study included 19 Western University students (11 females and eight males) with normal hearing and with English as a first language. Results Raw scores for the 48 tested passages were converted to rationalized arcsine units, and average passage scores more than 1 rationalized arcsine unit standard deviation from the mean were excluded. The internal reliability of the 32 remaining passages was assessed, and the two-way random effects intraclass correlation was .944. Conclusion The aim of our study was to create new CST stimuli with a more general North American accent in order to minimize accent effects on the speech perception scores. The study resulted in 32 passages of equivalent difficulty for listeners with normal hearing.

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