A Middle Cambrian trilobite faunule from the Meguma Group of Nova Scotia

1991 ◽  
Vol 28 (11) ◽  
pp. 1843-1853 ◽  
Author(s):  
Brian R. Pratt ◽  
John W. F. Waldron
Keyword(s):  
Nova Scotia ◽  
Middle East ◽  
West Africa ◽  
Deep Water ◽  
Middle Cambrian ◽  
Early Ordovician ◽  
Cambrian Trilobite ◽  
East And West ◽  
Faunal Similarity

The Meguma Group of southern Nova Scotia is a thick succession of mostly deep-water siliciclastic sedimentray rocks of uncertain age. Previous fossil finds have been in the Halifax Formation of the upper part of the sequence and have provided Early Ordovician ages. A newly discovered trilobite-bearing bed from the underlying Goldenville Formation yields Middle Cambrian taxa of Acado-Baltic affinity. Specimens belonging to Paradoxides (s.l.), Agraulos, Dorypyge, and Ellipsocephalidae indicate that the Meguma Group is an exotic succession with faunal similarity to the adjacent Avalon Terrane and to Middle Cambrian successions in Europe, the Middle East, and west Africa.

Reply to the discussion by J.W.F. Waldron and C.E. White on “Geochemical signature of Ordovician Mn-rich sedimentary rocks on the Avalonian shelf”1Appears in Canadian Journal of Earth Sciences, 2012, 49(6): 772–774 [doi: 10.1139/e2012-004].

2012 ◽  
Vol 49 (6) ◽  
pp. 775-780 ◽  
Author(s):  
Rolf L. Romer ◽  
Uwe Kroner
Keyword(s):  
Earth Sciences ◽  
Nova Scotia ◽  
Canadian Journal ◽  
Deep Water ◽  
Sedimentary Rocks ◽  
Geochronological Data ◽  
Early Ordovician ◽  
Geochemical Signature

In their comment, Waldron and White state that manganese-rich sedimentary rocks of Nova Scotia and Wales are Cambrian and were deposited in a deep-water turbidite basin called “Megumia” rather than on the Avalonian shelf. Available geochronological data are not in conflict with an Early Ordovician deposition age for manganese-rich sedimentary rocks north of the Rheic suture, including those of Nova Scotia and northern Wales. “Megumia” is part of the Avalonian plate, and the manganese-rich sediments were deposited on its shelf.

Contrasting U–Pb ages from plutons in the Bras d'Or and Mira terranes of Cape Breton Island, Nova Scotia

1990 ◽  
Vol 27 (9) ◽  
pp. 1200-1208 ◽  
Author(s):  
S. M. Barr ◽  
G. R. Dunning ◽  
R. P. Raeside ◽  
R. A. Jamieson
Keyword(s):  
Nova Scotia ◽  
Close Similarity ◽  
Zircon Age ◽  
Middle Cambrian ◽  
Cape Breton Island ◽  
Early Ordovician ◽  
Late Precambrian ◽  
Cape Breton ◽  
Devonian Age

U–Pb dates from zircon, titanite, and monazite in plutons of the Bras d'Or and Mira terranes of southern Cape Breton Island, combined with 40Ar/39Ar and other radiometric age data, indicate that the Bras d'Or and Mira terranes had separate magmatic and metamorphic histories until at least the Middle Cambrian and possibly until the Devonian. The Bras d'Or Terrane is characterized by abundant late Precambrian (ca. 565–555 Ma) dioritic to granitic plutons, as exemplified by the Shunacadie granodiorite ([Formula: see text], U–Pb zircon). Early Ordovician granitic plutons, such as the Kellys Mountain leucogranite with a U–Pb (zircon) age of 498 ± 2 Ma, occur locally. Titanite and 40Ar/39Ar (hornblende) ages from plutons and metamorphic units suggest that widespread metamorphism may have occurred between these plutonic events and (or) during the Early Ordovician plutonism.Plutons in the Mira Terrane appear to have been emplaced at about 620 Ma or before, as exemplified by the Chisholm Brook granodiorite ([Formula: see text]), and to have been unaffected by younger thermal events, as indicated by close similarity of U–Pb (zircon and titanite) and 40Ar/39Ar (hornblende) ages. Plutons of Devonian age are localized in an easterly trending belt in the central part of the terrane. In contrast to the Bras d'Or Terrane, widespread latest Precambrian (ca. 565–555 Ma) to Early Ordovician plutonism and metamorphism appear to have been absent. It is unlikely that the Mira and Bras d'Or terranes were juxtaposed before the Early Ordovician.

Cambrian shelf stratigraphy of North Greenland

1997 ◽  
pp. 1-120 ◽  
Author(s):  
Jon R. Ineson ◽  
John S. Peel
Keyword(s):  
Shallow Water ◽  
Deep Water ◽  
Carbonate Platform ◽  
Outer Shelf ◽  
Early Cambrian ◽  
Middle Cambrian ◽  
Water Trough ◽  
Water Carbonate ◽  
Shallow Water Carbonate ◽  
North Greenland

NOTE: This article was published in a former series of GEUS Bulletin. Please use the original series name when citing this article, for example: Ineson, J. R., & Peel, J. S. (1997). Cambrian shelf stratigraphy of North Greenland. Geology of Greenland Survey Bulletin, 173, 1-120. https://doi.org/10.34194/ggub.v173.5024 _______________ The Lower Palaeozoic Franklinian Basin is extensively exposed in northern Greenland and the Canadian Arctic Islands. For much of the early Palaeozoic, the basin consisted of a southern shelf, bordering the craton, and a northern deep-water trough; the boundary between the shelf and the trough shifted southwards with time. In North Greenland, the evolution of the shelf during the Cambrian is recorded by the Skagen Group, the Portfjeld and Buen Formations and the Brønlund Fjord, Tavsens Iskappe and Ryder Gletscher Groups; the lithostratigraphy of these last three groups forms the main focus of this paper. The Skagen Group, a mixed carbonate-siliciclastic shelf succession of earliest Cambrian age was deposited prior to the development of a deep-water trough. The succeeding Portfjeld Formation represents an extensive shallow-water carbonate platform that covered much of the shelf; marked differentiation of the shelf and trough occurred at this time. Following exposure and karstification of this platform, the shelf was progressively transgressed and the siliciclastics of the Buen Formation were deposited. From the late Early Cambrian to the Early Ordovician, the shelf showed a terraced profile, with a flat-topped shallow-water carbonate platform in the south passing northwards via a carbonate slope apron into a deeper-water outer shelf region. The evolution of this platform and outer shelf system is recorded by the Brønlund Fjord, Tavsens Iskappe and Ryder Gletscher Groups. The dolomites, limestones and subordinate siliciclastics of the Brønlund Fjord and Tavsens Iskappe Groups represent platform margin to deep outer shelf environments. These groups are recognised in three discrete outcrop belts - the southern, northern and eastern outcrop belts. In the southern outcrop belt, from Warming Land to south-east Peary Land, the Brønlund Fjord Group (Lower-Middle Cambrian) is subdivided into eight formations while the Tavsens Iskappe Group (Middle Cambrian - lowermost Ordovician) comprises six formations. In the northern outcrop belt, from northern Nyeboe Land to north-west Peary Land, the Brønlund Fjord Group consists of two formations both defined in the southern outcrop belt, whereas a single formation makes up the Tavsens Iskappe Group. In the eastern outcrop area, a highly faulted terrane in north-east Peary Land, a dolomite-sandstone succession is referred to two formations of the Brønlund Fjord Group. The Ryder Gletscher Group is a thick succession of shallow-water, platform interior carbonates and siliciclastics that extends throughout North Greenland and ranges in age from latest Early Cambrian to Middle Ordovician. The Cambrian portion of this group between Warming Land and south-west Peary Land is formally subdivided into four formations.The Lower Palaeozoic Franklinian Basin is extensively exposed in northern Greenland and the Canadian Arctic Islands. For much of the early Palaeozoic, the basin consisted of a southern shelf, bordering the craton, and a northern deep-water trough; the boundary between the shelf and the trough shifted southwards with time. In North Greenland, the evolution of the shelf during the Cambrian is recorded by the Skagen Group, the Portfjeld and Buen Formations and the Brønlund Fjord, Tavsens Iskappe and Ryder Gletscher Groups; the lithostratigraphy of these last three groups forms the main focus of this paper. The Skagen Group, a mixed carbonate-siliciclastic shelf succession of earliest Cambrian age was deposited prior to the development of a deep-water trough. The succeeding Portfjeld Formation represents an extensive shallow-water carbonate platform that covered much of the shelf; marked differentiation of the shelf and trough occurred at this time. Following exposure and karstification of this platform, the shelf was progressively transgressed and the siliciclastics of the Buen Formation were deposited. From the late Early Cambrian to the Early Ordovician, the shelf showed a terraced profile, with a flat-topped shallow-water carbonate platform in the south passing northwards via a carbonate slope apron into a deeper-water outer shelf region. The evolution of this platform and outer shelf system is recorded by the Brønlund Fjord, Tavsens Iskappe and Ryder Gletscher Groups. The dolomites, limestones and subordinate siliciclastics of the Brønlund Fjord and Tavsens Iskappe Groups represent platform margin to deep outer shelf environments. These groups are recognised in three discrete outcrop belts - the southern, northern and eastern outcrop belts. In the southern outcrop belt, from Warming Land to south-east Peary Land, the Brønlund Fjord Group (Lower-Middle Cambrian) is subdivided into eight formations while the Tavsens Iskappe Group (Middle Cambrian - lowermost Ordovician) comprises six formations. In the northern outcrop belt, from northern Nyeboe Land to north-west Peary Land, the Brønlund Fjord Group consists of two formations both defined in the southern outcrop belt, whereas a single formation makes up the Tavsens Iskappe Group. In the eastern outcrop area, a highly faulted terrane in north-east Peary Land, a dolomite-sandstone succession is referred to two formations of the Brønlund Fjord Group. The Ryder Gletscher Group is a thick succession of shallow-water, platform interior carbonates and siliciclastics that extends throughout North Greenland and ranges in age from latest Early Cambrian to Middle Ordovician. The Cambrian portion of this group between Warming Land and south-west Peary Land is formally subdivided into four formations.

scholarly journals A qualitative inquiry of access to and quality of primary healthcare in seven communities in East and West Africa (SevenCEWA): perspectives of stakeholders, healthcare providers and users

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Soter Ameh ◽  
Bolarinwa Oladimeji Akeem ◽  
Caleb Ochimana ◽  
Abayomi Olabayo Oluwasanu ◽  
Shukri F. Mohamed ◽  
...  
Keyword(s):  
Health Insurance ◽  
West Africa ◽  
Primary Healthcare ◽  
A Priori ◽  
Healthcare Providers ◽  
Health Coverage ◽  
Health Seeking ◽  
East And West ◽  
Universal Health

Abstract Background Universal health coverage is one of the Sustainable Development Goal targets known to improve population health and reduce financial burden. There is little qualitative data on access to and quality of primary healthcare in East and West Africa. The aim of this study was to describe the viewpoints of healthcare users, healthcare providers and other stakeholders on health-seeking behaviour, access to and quality of healthcare in seven communities in East and West Africa. Methods A qualitative study was conducted in four communities in Nigeria and one community each in Kenya, Uganda and Tanzania in 2018. Purposive sampling was used to recruit: 155 respondents (mostly healthcare users) for 24 focus group discussions, 25 healthcare users, healthcare providers and stakeholders for in-depth interviews and 11 healthcare providers and stakeholders for key informant interviews. The conceptual framework in this study combined elements of the Health Belief Model, Health Care Utilisation Model, four ‘As’ of access to care, and pathway model to better understand the a priori themes on access to and quality of primary healthcare as well as health-seeking behaviours of the study respondents. A content analysis of the data was done using MAXQDA 2018 qualitative software to identify these a priori themes and emerging themes. Results Access to primary healthcare in the seven communities was limited, especially use of health insurance. Quality of care was perceived to be unacceptable in public facilities whereas cost of care was unaffordable in private facilities. Health providers and users as well as stakeholders highlighted shortage of equipment, frequent drug stock-outs and long waiting times as major issues, but had varying opinions on satisfaction with care. Use of herbal medicines and other traditional treatments delayed or deterred seeking modern healthcare in the Nigerian sites. Conclusions There was a substantial gap in primary healthcare coverage and quality in the selected communities in rural and urban East and West Africa. Alternative models of healthcare delivery that address social and health inequities, through affordable health insurance, can be used to fill this gap and facilitate achieving universal health coverage.

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