The sequence and correlation of Early Ordovician (Arenig) graptolite faunas in the Richardson Trough and Misty Creek Embayment, Yukon Territory and District of Mackenzie, Canada

2006 ◽  
Vol 43 (12) ◽  
pp. 1791-1820 ◽  
Author(s):  
D E Jackson ◽  
A C Lenz

Four graptolite biozones are recorded from the Arenig portion of the Road River Group in the Richardson and Mackenzie mountains in the Yukon and Northwest Territories. In ascending order, these zones are Tetragraptus approximatus, Pendeograptus fruticosus, Didymograptus bifidus, and Parisograptus caduceus australis (new). The Castlemainian stage may be represented by nongraptolitic massive bedded chert. The Arenig–Llanvirn boundary is drawn below the first occurrence of Undulograptus austrodentatus. Fifty-four graptolite taxa are present, and 16 of these species and subspecies are recorded for the first time in this deep-water biotope, namely, Didymograptus? cf. adamantinus, D. asperus, D. dilatans, D. cf. kurcki, D. validus communis, Holmograptus aff. leptograptoides, H. sp. A, Isograptus? sp. nov. A, I. ? dilemma, Keblograptus geminus, Pseudisograptus manubriatus harrisi, Ps. m. koi, Ps. m. janus, Ps. cf. tau, Xiphograptus lofuensis, and Zygograptus cf. abnormis.

1975 ◽  
Vol 12 (4) ◽  
pp. 663-697 ◽  
Author(s):  
Rolf Ludvigsen

Ordovician strata of the South Nahanni River area occur as a western fine clastic facies with graptolitic faunas (Road River Formation) and an eastern carbonate facies with shelly faunas (Broken Skull, Sunblood, Esbataottine, and Whittaker Formations). The lithofacies are controlled by major tectonic features. In the early Ordovician the Selwyn Basin received fine clastic sedimentation (Road River) while carbonate sedimentation (Broken Skull, Sunblood, Esbataottine) was confined to the Root Basin and the fringes of the emergent Redstone Arch. Later in the Ordovician a pronounced transgression caused a marked eastwardly shift of facies belts and resulted in the flooding of the Arch and deposition of a widespread carbonate sheet (Whittaker) in the northeastern part of the study area.The carbonate facies of the Root Basin and south of the Redstone Arch contains a complete record of shelly faunas of Canadian to, probably, Maysvillian age. The Broken Skull Formation consists of craggy weathering, variably sandy carbonates and contains, in its highest parts, the Hesperonomia fauna (Canadian). The Sunblood Formation consists of generally resistant, red-orange-buff weathering limestones and minor dolostones and contains two faunas; the Orthidiella-'Goniotelina' fauna (Whiterockian) and the Bathyurus sp. 1 fauna (?Chazyan). The Esbataottine Formation (proposed) comprises moderately recessive, grey-buff weathering limestones and contains two faunas; the Mimella fauna (Chazyan) and the Doleroides fauna (Blackriveran). The lower Whittaker Formation (Trentonian to ?Maysvillian) comprises three lithosomes containing discrete faunas which appear to represent coeval communities: The Strophomena-Ceraurus fauna in thinly bedded, argillaceous limestones; the Bighornia-Thaerodonta fauna in well bedded, nonargillaceous limestones; and the Hesperorthis-Oepikina fauna in well bedded dolostones. A unique fauna of deep water aspect, the Cryptolithus-Anataphrus fauna, occurs in shales and black limestones of the Road River Formation and is, in part, equivalent to the faunas of the lower Whittaker Formation. The Sunblood, Esbataottine, and Whittaker Formations contain abundant and well preserved silicified trilobites; many of which are reported for the first time from western and northern Canada.


2001 ◽  
Vol 75 (2) ◽  
pp. 466-470 ◽  
Author(s):  
Robert B. Blodgett ◽  
Jiří Frýda ◽  
Alfred C. Lenz

Despite the rapidly expanding knowledge of Lower Devonian brachiopod faunas of the Western Cordillera of Canada (Lenz, 1976, 1977a, 1977b, 1982; Ludvigsen, 1970; Perry, 1984; Perry and Lenz, 1978; Perry et al., 1974, 1981), equivalent data on coeval gastropod faunas from this region are non-existent; to date, no publications have appeared in which gastropods have been described. Blodgett et al. (1988, table 1) provided faunal lists for two Lower Devonian localities in Western Canada: 1) Lochkovian-Emsian age collections from the Mackenzie Mountains, Northwest Territories, collected by the late D. G. Perry as part of his Ph.D. dissertation (Perry, 1984); and 2) an early Emsian collection from the Mt. Lloyd George area, British Columbia. We are currently examining the gastropod material recovered by A. C. Lenz from his richly diverse collections in the Royal Creek area, Yukon Territory, equivalent in age to those gathered by D. G. Perry from the Mackenzie Mountains. This note is the first of several papers focused on these paleobiogeographically significant faunas, and it is our desire to ultimately make clear the character of this Early Devonian province, which appears to include strata of British Columbia, Yukon and Northwest Territories, as well as the non-accreted portion of adjacent east-central Alaska.


1970 ◽  
Vol 48 (3) ◽  
pp. 433-435
Author(s):  
Y. Hiratsuka

From inoculation experiments and morphological examinations, the aecial state of Pucciniastrum sparsum (Wint.) E. Fisch. (= Thekopsora sparsa (Wint.) Magn.) has been identified for the first time in North America from specimens collected in the Northwest Territories and the Yukon Territory. Picea glauca (Moench) Voss, P. mariana (Mill.) BSP., and P. pungens Engelm. (from inoculation only) are reported as new hosts of this fungus. An expanded description of the spermogonia and aecia of the fungus is given.


1987 ◽  
Vol 24 (4) ◽  
pp. 643-653 ◽  
Author(s):  
Alexander D. McCracken ◽  
Alfred C. Lenz

Ordovician conodont faunas from the fine-grained clastic Road River Group in northern Yukon Territory contain a mixture of species from both warm- and cold-water regions. This group in southwestern Northwest Territories also has mixed faunas, whereas conodonts from the carbonate facies are more characteristic of the warm-water regions.Six conodont associations and biozones are identified from the Yukon. Some, such as the early Llanvirn "Cordylodus" horridus – Spinodus spinatus association, contain reworked elements. The Pygodus serra Zone (middle–late Llanvirn) is within the upper P. tentaculatus Zone and well below the G. euglyphus Zone. Genera include Ansella, Periodon, Protopanderodus, Pygodus, and Walliserodus.At Peel River, conodonts are within the P. pacificus Zone. The Blackstone River conodonts occur above the P. pacificus Zone and below the G. persculptus Zone (?) and include Oulodus rohneri, Plectodina florida, and Noixodontus. Amorphognathus ordovicicus, Gamachignathus ensifer, O. ulrichi, and Plectodina tenuis occur in both faunas. These represent Fauna 12, found in late Richmondian strata, rather than the Gamachian Fauna 13 and are assigned to the G. ensifer Zone; both occurrences of G. ensifer are biohorizons. The C.? extraordinarius and G. persculptus zones are not recognized at Peel and Rock rivers and Tetlit Creek.The Ozarkodina n. sp. A – Icriodella sp. B association occurs at Pat Lake between the G. persculptus Zone (?) and the underlying P. pacificus Zone. The Ozarkodina have a Silurian aspect but must be regarded as Ordovician.The Ordovician–Silurian boundary in the Road River Group of the Yukon is best defined using graptolites because of the rare occurrence of conodonts.


2003 ◽  
Vol 140 (2) ◽  
pp. 131-156 ◽  
Author(s):  
D. E. JACKSON ◽  
A. C. LENZ

Twenty-two graptolite species are described from the Tremadoc portion of the Road River Group. In a 220 m thick, graptolite-rich section on Peel River, six graptolite biozones are recognized which in ascending order are: Staurograptus dichotomus, Anisograptus matanensis, Adelograptus cf. A. tenellus, Adelograptus antiquus, Kiaerograptus pritchardi and Paradelograptus kinnegraptoides. The Psigraptus fauna appears to be confined to a single bedding-plane within a thick interval dominated by Adelograptus cf. A. tenellus, and for this reason we propose a new zone characterized by the latter species rather than identify a Psigraptus Biozone as in China. The Adelograptus cf. A. tenellus Biozone has yielded Adelograptus? bulmani Spjeldnaes 1963, which we propose as the type species for the new genus Ancoragraptus. Graptolites recorded from the Tremadoc of the Yukon for the first time are: Ancoragraptus bulmani, Clonograptus magnificus, C. cf. C. multiplex, C. cf. C. rigidus, Hunnegraptus copiosus, Kiaerograptus? bulmani and K? kutchini sp. nov.


1976 ◽  
Vol 13 (10) ◽  
pp. 1466-1478 ◽  
Author(s):  
D. G. Perry ◽  
B. D. E. Chatterton

The trilobite genus Phacops is documented for the first time in northwestern or Arctic Canada from Emsian age beds of the Delorme Formation, western Mackenzie Mountains. Phacops natlenis n. sp. is described; it shows closest morphologic affinity to P. spedeni Chatterton from late Emsian age beds of southeastern Australia. Other Emsian trilobite genera from the Delorme Formation in the Sekwi Mountain map-area, Mackenzie Mountains include: Lacunoporaspis, Ceratarges?, Acanthopyge (Mephiarges), Leonaspis, and Koneprusia?.


1971 ◽  
Vol 49 (6) ◽  
pp. 899-902
Author(s):  
James H. Ginns ◽  
Ruth Macrae

Forty-eight species of Polyporaceae are reported for the first time from the four western Provinces and Yukon and District of Mackenzie of the Northwest Territories. The number of species reported are from Manitoba 11, Saskatchewan 8, Alberta 20, British Columbia 10, Yukon Territory 4, and Northwest Territories (Mackenzie Dist.) 13.


2020 ◽  
pp. jgs2020-170
Author(s):  
P. Cózar ◽  
I. D. Somerville

Analysis of foraminiferal assemblages from the Viséan-Serpukhovian boundary interval in Britain has led to the recognition that levels correlated with the first occurrence of Lochriea ziegleri at the base of the Serpukhovian Stage can be established by the foraminifer Neoarchaediscus gregorii in England and Scotland, which first occurs from the Single Post and Cockleshell limestones in northern England and laterally equivalent levels, as well as Asteroarchaediscus bashkiricus, and A. rugosus (except for South Wales). Contrary to some previous studies, the base of the Serpukhovian does not equate with the base of the Namurian (Pendleian Substage), but lies approximately at the early-late Brigantian boundary, based on the first occurrence of Neoarchaediscus postrugosus. Four foraminiferal assemblages are distinguished in the early Serpukhovian (7-10) and four assemblages in the late Serpukhovian (11-14). Despite the contrast in facies, it is now recognised for the first time that throughout the Midland Valley of Scotland, northern England and South Wales. the foraminiferal assemblages from shallow-water platform facies are completely compatible with the ammonoid subzones from deep-water basinal facies, with no apparent mismatches. There appears to be close comparability of foraminiferal assemblages and first appearance datums of marker species with most of the international foraminiferal zonal schemes in Russia.Supplementary material:https://doi.org/10.6084/m9.figshare.c.5240408


1994 ◽  
Vol 68 (2) ◽  
pp. 218-223 ◽  
Author(s):  
J. Keith Rigby ◽  
Brian D. E. Chatterton

Several specimens of the small hexactinellid, Cyathophycus mackenziensis n. sp., were collected from pale brown, shaly mudstone of the Road River Formation. The sponges are of Wenlock age and were collected from near Avalanche Lake, Mackenzie Mountains, Northwest Territories, Canada. The small, steeply obconical sponges have skeletons in crudely ranked quadrules to at least third-order, with first-order openings generally 2 mm high and 1 mm wide. Successive orders decrease in stages approximately half that of larger elements. A moderately irregular dermal(?) layer with circular parietal gaps is suggested in some specimens. The new species is consistently finer textured than either the type species Cyathophycus reticulatus Walcott, 1879, or the later described Cyathophycus quebecensis Dawson, 1889.


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