Cambrian trilobites in central Newfoundland volcanic belt

1968 ◽  
Vol 105 (4) ◽  
pp. 372-377 ◽  
Author(s):  
Marshall Kay ◽  
Niles Eldredge
Keyword(s):  
North America ◽  
New World ◽  
Volcanic Rocks ◽  
Volcanic Belt ◽  
Middle Cambrian ◽  
Atlantic Province ◽  
Volcanic Belts

SUMMARYThe discovery of species of Kootenia and Bailiella known from the Middle Cambrian of western Newfoundland (“Pacific Province”) and southeastern Newfoundland (“Atlantic Province”) in limestone within volcanic rocks near New World Island, eastern Notre Dame Bay, is the first demonstration of the presence of Cambrian in the volcanic belts in North America, and also shows the mixing of forms from the two provinces.

Geochemical and metallogenic relations in volcanic rocks of the southern Slave Province: implications for late Neoarchean tectonics

2006 ◽  
Vol 43 (12) ◽  
pp. 1835-1857 ◽  
Author(s):  
A M Goodwin ◽  
M B Lambert ◽  
O Ujike
Keyword(s):  
Plate Tectonics ◽  
Early Stage ◽  
Volcanic Rocks ◽  
Volcanic Belt ◽  
Gold Deposits ◽  
Tectonic Plates ◽  
Slave Province ◽  
Volcanogenic Massive Sulphide ◽  
Lode Gold Deposits ◽  
Volcanic Belts

Late Neoarchean volcanic belts in the southern Slave Province include (1) in the east, the Cameron River – Beaulieu River belts, which are characterized by stratigraphically thin, flow-rich, classic calc-alkaline, arc-type sequences with accompanying syngenetic volcanogenic massive sulphide deposits; and (2) in the west, the Yellowknife belt, which is characterized by stratigraphically thick, structurally complex, pyroclastic-rich, adakitic, back-arc basin-type sequences, with accompanying epigenetic lode-gold deposits. The volcanic belt association bears persuasive chemical evidence of subduction-initiated magma generation. However, the greenstone belts, together with coeval matching patterned belts in Superior Province of the southern Canadian Shield, bear equally persuasive evidence of prevailing autochthonous–parautochthonous relations with respect to component stratigraphic parts and to older gneissic basement. The eastern and western volcanic belts in question are petrogenetically ascribed to a "westerly inclined" (present geography) subduction zone(s) that produced shallower (east) to deeper (west), slab-initiated, mantle wedge-generated, parent magmas. This early stage microplate tectonic process involved modest mantle subduction depths, small tectonic plates, and small sialic cratons. In the larger context of Earth's progressively cooling, hence subduction-deepening mantle, this late Neoarchean greenstone belt development (2.73–2.66 Ga) merged with the massive end-Archean tonalite–trondhjemite–granodiorite–granite (TTGG) "bloom" (2.65–2.55 Ga), resulting in greatly enhanced craton stability. Successive subduction-deepening, plate-craton-enlarging stages, with appropriate metallotectonic response across succeeding Proterozoic time and beyond, led to modern-mode plate tectonics.

Stratigraphy, paleogeography, and tectonic setting of the Coldbrook Group in the Caledonia Highlands of southern New Brunswick

1977 ◽  
Vol 14 (6) ◽  
pp. 1263-1275 ◽  
Author(s):  
P. S. Giles ◽  
A. A. Ruitenberg
Keyword(s):  
New Brunswick ◽  
Tectonic Setting ◽  
Volcanic Rocks ◽  
Volcanic Belt ◽  
Fine Grained ◽  
Arc Model ◽  
Basement Rocks ◽  
Northwestern Margin ◽  
Intracratonic Basin ◽  
Volcanic Belts

The late Precambrian Coldbrook volcanic sequence and stratigraphic equivalents in southern New Brunswick can be divided into three distinct belts. These have been named the Eastern, Central and Western Volcanic Belts.The Eastern Volcanic Belt, along the Bay of Fundy coast, is characterized by intensely deformed mafic and felsic flows, tuffs, and abundant related volcanogenic sediments. Two thick arkosic sedimentary units in this belt reflect extensive intervals of volcanic quiescence. Fine-grained siliceous siltstone and conglomerate, locally intercalated with these rocks, have probably been derived from erosion of older Precambrian basement rocks to the northwest.The Central Volcanic Belt is composed of generally weakly deformed felsic and lesser mafic flows, and coarse lithic tuffs (including ignimbrites), and very minor intercalated sediments. The almost complete lack of water-lain sediments and presence of ignimbrites suggests subaerial deposition for most of these volcanic rocks. The relationship between rocks of the Central and Eastern Volcanic Belts is one of facies equivalence. The Western Volcanic Belt is also composed of felsic and minor mafic flows and tuffs that resemble those of the Central Volcanic Belt, but they are intensely deformed. Minor volcanogenic sedimentary rocks are intercalated with the volcanic rocks along the northwestern margin of this belt.The nature and distribution of major lithofacies belts in the Coldbrook Group and stratigraphic equivalents appear to be consistent with deposition along the margin of an intracratonic basin. It is possible, however, that further work may prove an ensialic island arc model to be a viable alternative.

Early Paleozoic Hyolitha from North America: reexamination of Walcott's and Resser's type specimens

1988 ◽  
Vol 62 (2) ◽  
pp. 218-233 ◽  
Author(s):  
John Mark Malinky
Keyword(s):  
North America ◽  
Lower Cambrian ◽  
Type Species ◽  
New Genus ◽  
Early Paleozoic ◽  
Type Specimens ◽  
Middle Cambrian ◽  
Upper Cambrian ◽  
New Family ◽  
The Family

Concepts of the family Hyolithidae Nicholson fide Fisher and the genera Hyolithes Eichwald and Orthotheca Novak have been expanded through time to encompass a variety of morphologically dissimilar shells. The Hyolithidae is here considered to include only those hyolithid species which have a rounded (convex) dorsum; slopes on the dorsum are inflated, and the venter may be flat or slightly inflated. Hyolithes encompasses species which possess a low dorsum and a prominent longitudinal sulcus along each edge of the dorsum; the ligula is short and the apertural rim is flared. The emended concept of Orthotheca includes only those species of orthothecid hyoliths which have a subtriangular transverse outline and longitudinal lirae covering the shell on both dorsum and venter.Eighteen species of Hyolithes and one species of Orthotheca from the Appalachian region and Western Interior were reexamined in light of more modern taxonomic concepts and standards of quality for type material. Reexamination of type specimens of H. similis Walcott from the Lower Cambrian of Newfoundland, H. whitei Resser from the Lower Cambrian of Nevada, H. billingsi Walcott from the Lower Cambrian of Nevada, H. gallatinensis Resser from the Upper Cambrian of Wyoming, and H. partitus Resser from the Middle Cambrian of Alabama indicates that none of these species represents Hyolithes. Hyolithes similis is here included under the new genus Similotheca, in the new family Similothecidae. Hyolithes whitei is designated as the type species of the new genus Nevadotheca, to which H. billingsi may also belong. Hyolithes gallatinensis is referred to Burithes Missarzhevsky with question, and H. partitus may represent Joachimilites Marek. The type or types of H. attenuatus Walcott, H. cecrops Walcott, H. comptus Howell, H. cowanensis Resser, H. curticei Resser, H. idahoensis Resser, H. prolixus Resser, H. resseri Howell, H. shaleri Walcott, H. terranovicus Walcott, and H. wanneri Resser and Howell lack shells and/or other taxonomically important features such as a complete aperture, rendering the diagnoses of these species incomplete. Their names should only be used for the type specimens until better preserved topotypes become available for study. Morphology of the types of H.? corrugatus Walcott and “Orthotheca” sola Resser does not support placement in the Hyolitha; the affinities of these species are uncertain.

Dress in North America, The New World 1492-1800.

1991 ◽  
Vol 25 (2) ◽  
pp. 278
Author(s):  
Michele Majer ◽  
Diana de Marly
Keyword(s):  
North America ◽  
New World

Petrology and geochemistry of Cambrian volcanic rocks from the Avalon Zone in New Brunswick

1985 ◽  
Vol 22 (6) ◽  
pp. 881-892 ◽  
Author(s):  
John D. Greenough ◽  
S. R. McCutcheon ◽  
V. S. Papezik
Keyword(s):  
New Brunswick ◽  
Volcanic Rocks ◽  
Trace Element Geochemistry ◽  
Element Geochemistry ◽  
Middle Cambrian ◽  
Mafic Rocks ◽  
Rock Types ◽  
Petrology And Geochemistry ◽  
Eastern Seaboard ◽  
Highly Evolved

Lower to Middle Cambrian volcanic rocks occur within the Avalon Zone of southern New Brunswick at Beaver Harbour and in the Long Reach area. The Beaver Harbour rocks are intensely altered, but the major- and trace-element geochemistry indicates that they could be highly evolved (basaltic andesites) within-plate basalts. The mafic flows from the Long Reach area form two chemically and petrologically distinct groups: (1) basalts with feldspar phenocrysts that represent evolved continental tholeiites with some oceanic characteristics; and (2) a group of aphyric basalts showing extremely primitive continental tholeiite compositions, also with oceanic affinities and resembling some rift-related Jurassic basalts on the eastern seaboard. Felsic pyroclastic rocks in the Long Reach area make the suite bimodal. This distribution of rock types supports conclusions from the mafic rocks that the area experienced tension throughout the Early to Middle Cambrian.

Toward a biogeographic regionalization of the Nearctic region: Area nomenclature and digital map

Zootaxa ◽  
2021 ◽  
Vol 5027 (3) ◽  
pp. 351-375
Author(s):  
TANIA ESCALANTE ◽  
GERARDO RODRÍGUEZ-TAPIA ◽  
JUAN J. MORRONE
Keyword(s):  
North America ◽  
Transition Zone ◽  
Rocky Mountain ◽  
Volcanic Belt ◽  
Neotropical Region ◽  
The Arctic ◽  
Digital Map ◽  
Biogeographic Regionalization ◽  
Sierra Madre ◽  
Nearctic Region

We provide a preliminary nomenclatural proposal and a digital map of the Nearctic region, based on published regionalizations, especially Dice (1943), and applying the International Code of Area Nomenclature. The Nearctic region is comprised of three subregions (one of them with two dominions), one transition zone and 29 provinces. The Arctic subregion, in northern North America and Greenland, includes the Eskimoan, Hudsonian, Aleutian and Sitkan provinces. The Western subregion, in western North America, includes the Californian dominion, with the Californian and Oregonian provinces; and the Rocky Mountain dominion, including the Montanian, Saskatchewan, Palusian, Artemisian, Coloradan, Kansan, Mohavian, Navahonian, Sonoran, Chihuahuan, Comanche, and Baja California provinces. The Alleghany subregion, in eastern North America, includes the Illinoian, Canadian, Carolinian, Texan, Austroriparian, and Tamaulipan provinces. The Mexican Transition Zone, situated in the area of overlap with the Neotropical region, includes the Sierra Madre Occidental, Sierra Madre Oriental, Transmexican Volcanic Belt, Sierra Madre del Sur and Chiapas Highlands provinces.  

A numerical analysis of morpho-geographic groups of cultivars of Humulus lupulus based on samples of cones

1981 ◽  
Vol 59 (3) ◽  
pp. 311-324 ◽  
Author(s):  
Ernest Small
Keyword(s):  
Numerical Analysis ◽  
North America ◽  
North American ◽  
New World ◽  
Geographical Origin ◽  
Humulus Lupulus ◽  
Numerical Analyses ◽  
Hybrid Origin ◽  
Morphological Examination ◽  
Humulus Lupulus L

Numerical analyses of hop (strobilus) samples showed that the geographical origin of cultivars of Humulus lupulus L. from North America, Britain, continental Europe, and Japan can be identified with considerable reliability on the basis of morphological examination. Samples of hybrid origin between North American and European plants tended to be similar to American cultivars, but often showed combinations of Old and New World characteristics, making their identification problematical.

scholarly journals Multiple Introductions of the Old World Begomovirus Tomato yellow leaf curl virus into the New World

2007 ◽  
Vol 73 (21) ◽  
pp. 7114-7117 ◽  
Author(s):  
Siobain Duffy ◽  
Edward C. Holmes
Keyword(s):  
North America ◽  
New World ◽  
Tomato Yellow Leaf ◽  
Yellow Leaf ◽  
Old World ◽  
Multiple Introductions ◽  
The Caribbean ◽  
Genomic Regions ◽  
Leaf Curl Virus ◽  
Leaf Curl

ABSTRACT A phylogenetic analysis of three genomic regions revealed that Tomato yellow leaf curl virus (TYLCV) from western North America is distinct from TYLCV isolated in eastern North America and the Caribbean. This analysis supports a second introduction of this Old World begomovirus into the New World, most likely from Asia.

Meadowcroft Rockshelter — Retrospect 1977: Part 1

1979 ◽  
Vol 1 (1) ◽  
pp. 3-44 ◽  
Author(s):  
J. M. Adovasio ◽  
J. D. Gunn ◽  
J. Donahue ◽  
R. Stuckenrath ◽  
J. Guilday ◽  
...  
Keyword(s):  
North America ◽  
Food Processing ◽  
New World ◽  
Western Hemisphere ◽  
Washington County ◽  
Northeastern North America ◽  
Southwestern Pennsylvania

Meadowcroft Rockshelter is a deeply stratified multicomponent site in Washington County, southwestern Pennsylvania. The eleven well defined stratigraphic units identified at the site span at least 16,000, and perhaps 19,000 years of intermittent occupation by groups representing all of the major cultural stages/periods now recognized in northeastern North America. Throughout the extant sequence, the site served as a locus for hunting, collecting and food processing activities which involved the seasonal exploitation of the immediately adjacent Cross Creek valley and contiguous uplands. Presently, Meadowcroft Rockshelter represents the earliest well dated evidence of man in the New World as well as the longest occupational sequence in the Western Hemisphere.

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