The Cambrian Fauna of the Leny Limestone, Perthshire, Scotland

2007 ◽  
Vol 98 (02) ◽  
pp. 199-218 ◽  
Author(s):  
Terence P. Fletcher ◽  
Adrian W. A. Rushton
Keyword(s):  
New York ◽  
North American ◽  
Lower Cambrian ◽  
Outer Edge ◽  
Open Ocean ◽  
Middle Cambrian ◽  
Middle Ordovician ◽  
The North ◽  
Appalachian Orogen ◽  
Selection Of

ABSTRACTDark limestones in the old quarries at Leny, Perthshire contain sparse beds with tiny fossils. They are poorly preserved and, though barely affected by the Ordovician Grampian Event tectonism, there is some taphonomic distortion and many are corroded along stylolitised horizons. The fauna mainly comprises trilobites of two types, open-ocean miomerids and polymerid shelf dwellers. MiomeridsCondylopygecf.eliandKiskinella cristataindicate a stratigraphical position equivalent to the base of the paradoxidid Amgan Stage of Siberia; traditionally regarded as ‘Middle Cambrian’. However, the bulk of the Leny miomerids, notably species ofPagetides, are forms described from the outer edge of Laurentia, within theBonnia–OlenellusZone, where it is considered to be ‘Lower Cambrian’. The Leny polymerids were likely transported off-shelf and some are conspecific with taxa in the Laurentian allochthonous Quebec and New York successions of the Early–Middle Ordovician (Taconic) Appalachian Orogen. The Leny Limestone and Shale Member of the Keltie Water Grit Formation is part of the Dalradian Supergroup deposited in an off-shelf Caledonide Grampian Terrane of the Humber Tectonostratigraphical Zone, midway between the North American successions and the Greenland Caledonides.Additional to the trilobites, brachiopods, sponges, hyoliths, bradoriids and a selection of indeterminable organic fragments occur; none of which has any particular age significance.

Lower Cambrian pediculate lingulids from Yunnan, China

1993 ◽  
Vol 67 (5) ◽  
pp. 788-798 ◽  
Author(s):  
Jin Yugan ◽  
Hou Xianguang ◽  
Wang Huayu
Keyword(s):  
New York ◽  
British Columbia ◽  
Lower Cambrian ◽  
Structure And Function ◽  
The Other ◽  
Burgess Shale ◽  
Middle Cambrian ◽  
Middle Ordovician ◽  
Early Ordovician ◽  
And Function

The vermiform pedicle is one of the most distinctive organs of modern lingulids, but it is rarely preserved. Only two fossil specimens of lingulids with pedicle casts have been reported, one from the Ordovician and the other from the Devonian. No record of fossil pedicles of Lingulella and Lingulepis, the dominant Cambrian and Early Ordovician lingulids, is known. Fossil lingulids from the Lower Cambrian of Chengjiang County, Yunnan, suggest that the structure and function of the pedicle of the lingulids has not changed significantly from its first appearance. A comparison of fossil pedicle of lingulids from the Lower Cambrian, Chengjiang County (China), the Burgess Shale, Middle Cambrian, British Columbia (Canada), the Trenton Formation, Middle Ordovician, New York (U.S.A.), and the Devonian, Devonshire (England, U.K.) shows that the delthyrial area to which the pedicle muscles are attached was reduced in length through time until these muscles were completely embraced by the two valves.Two species, Lingulella chengjiangensis n. sp. and Lingulepis malongensis Rong, are described.

First record of Labyrinthus soraufi Kobluk from the southern Appalachians: Lower Cambrian Shady Dolomite, Virginia

1982 ◽  
Vol 19 (5) ◽  
pp. 1094-1098 ◽  
Author(s):  
David R. Kobluk
Keyword(s):  
North American ◽  
Lower Cambrian ◽  
First Record ◽  
Geographic Range ◽  
Southern Appalachians ◽  
Middle Cambrian ◽  
The North

Labyrinthus soraufi Kobluk 1979, previously known only from the upper Lower Cambrian Forteau Formation of southern Labrador, has been found within upper Lower Cambrian to lower Middle Cambrian Epiphyton mounds from the upper part of the Shady Dolomite in southwestern Virginia. This problematical fossil was a contributor to framework growth in both of its known occurrences. This find extends the geographic range of this fossil to include the southern Appalachians, and shows that L. soraufi is not a fossil unique to the Cambrian of Labrador but may possibly occur more widely through the North American Lower (and Middle?) Cambrian. The absence of archaeocyathids from the Epiphyton mounds in the Upper Shady Formation shows that L. soraufi was not restricted to archaeocyathid-bearing mounds or reefs.

Étude géologique du socle ante-mésozoique au nord du Massif Armoricain: limites et structures de la Domnonée

1975 ◽  
Vol 279 (1288) ◽  
pp. 123-135 ◽  
Keyword(s):  
Seismic Data ◽  
Lower Cambrian ◽  
The South ◽  
The West ◽  
Middle Cambrian ◽  
Middle Ordovician ◽  
Fundamental Structure ◽  
The North ◽  
Caledonian Orogeny

The study of samples taken on the bottom of the sea north of the Massif Armoricain, and the geological, magnetic, gravimetric and seismic data collected on land and at sea, confirms that this region is characterized by: (1) a series of horsts where fragments of Pentevrian and Cadomian orogenies outcrops; (2) gullies, or synclines, of Palaeozoic terrain. The separation of the horsts is the result of tectonic shearing which developed during the Ordovician, Carboniferous and Triassic ages. The Cadomian chain, which constituted the fundamental structure of the region, was broken up very early and is no longer recognizable. In the west, traces of this chain seem to have lasted until the Llanvirnian. In the east, the uplands, which were probably less harsh, were levelled before the start of the lower Cambrian age. A general upwarp of the eastern part between the middle Cambrian and the middle Ordovician could correspond to a reaction to the Caledonian orogeny. The northern part of the Alassif Armoricain had little part in the Hercynian paroxysm, however, this period witnessed an important tangential tectonism, the horsts riding over the edges of the synclines. The western formations show more marked structures than the eastern formations. The area which has been studied largely corresponds to the Domnonean domain, a puzzle of horsts and grabens. The Domnonea is itself a large horst, limited to the north by thick Palaeozoic sequences and to the south by the central Armorican zone and the Mancellian domain.

scholarly journals Impacts of Large-Scale Circulation on Urban Ambient Concentrations of Gaseous Elemental Mercury in New York, USA

2017 ◽  
Author(s):  
Huiting Mao ◽  
Dolly Hall ◽  
Zhuyun Ye ◽  
Ying Zhou ◽  
Dirk Felton ◽  
...  
Keyword(s):  
New York ◽  
North American ◽  
Large Scale ◽  
Measurement Data ◽  
Elemental Mercury ◽  
Urban Site ◽  
Large Scale Circulation ◽  
Gaseous Elemental Mercury ◽  
The North ◽  
The Impact

Abstract. The impact of large-scale circulation on urban gaseous elemental mercury (GEM) was investigated through analysis of 2008–2015 measurement data from an urban site in New York City (NYC), New York, USA. Distinct annual cycles were observed in 2009–2010 with mixing ratios in warm seasons (i.e. spring–summer) 10–20 ppqv (~ 10 %–25 %) higher than in cool seasons (i.e. fall–winter). This annual cycle was disrupted in 2011 by an anomalously strong influence of the North American trough in that warm season and was reproduced in 2014 with annual amplitude enhanced up to ~ 70 ppqv associated with a particularly strong Bermuda High. North American trough axis index (TAI) and intensity index (TII) were used to characterize the effect of the North American trough on NYC GEM especially in winter and summer. The intensity and position of the Bermuda High had a significant impact on GEM in warm seasons supported by a strong correlation (r reaching 0.96, p 

scholarly journals Carbon cycling in the North American coastal ocean: A synthesis

2018 ◽  
Author(s):  
Katja Fennel ◽  
Simone Alin ◽  
Leticia Barbero ◽  
Wiley Evans ◽  
Timotheé Bourgeois ◽  
...  
Keyword(s):  
Ocean Acidification ◽  
North American ◽  
Inorganic Carbon ◽  
Co2 Flux ◽  
Carbon Fluxes ◽  
Coastal Ocean ◽  
Open Ocean ◽  
The Arctic ◽  
The North ◽  
Anthropogenic Carbon

Abstract. A quantification of carbon fluxes in the coastal ocean and across its boundaries, specifically the air-sea, land-to-coastal-ocean and coastal-to-open-ocean interfaces, is important for assessing the current state and projecting future trends in ocean carbon uptake and coastal ocean acidification, but is currently a missing component of global carbon budgeting. This synthesis reviews recent progress in characterizing these carbon fluxes with focus on the North American coastal ocean. Several observing networks and high-resolution regional models are now available. Recent efforts have focused primarily on quantifying net air-sea exchange of carbon dioxide (CO2). Some studies have estimated other key fluxes, such as the exchange of organic and inorganic carbon between shelves and the open ocean. Available estimates of air-sea CO2 flux, informed by more than a decade of observations, indicate that the North American margins act as a net sink for atmospheric CO2. This net uptake is driven primarily by the high-latitude regions. The estimated magnitude of the net flux is 160 ± 80 Tg C/y for the North American Exclusive Economic Zone, a number that is not well constrained. The increasing concentration of inorganic carbon in coastal and open-ocean waters leads to ocean acidification. As a result conditions favouring dissolution of calcium carbonate occur regularly in subsurface coastal waters in the Arctic, which are naturally prone to low pH, and the North Pacific, where upwelling of deep, carbon-rich waters has intensified and, in combination with the uptake of anthropogenic carbon, leads to low seawater pH and aragonite saturation states during the upwelling season. Expanded monitoring and extension of existing model capabilities are required to provide more reliable coastal carbon budgets, projections of future states of the coastal ocean, and quantification of anthropogenic carbon contributions.

scholarly journals A procura pela libertação em Exodus: a dimensão trágica do deslocamento de refugiados nas imagens de Mauricio Lima

2020 ◽  
Vol 7 ◽  
pp. 1-18
Author(s):  
Janayna Ávila
Keyword(s):  
New York ◽  
Qualitative Research ◽  
North American ◽  
New York Times ◽  
The New York Times ◽  
The North ◽  
Personal Interactions ◽  
Analysis Of The Images ◽  
Expressive Dimension

This article reflects on the issue of the refugees from four photographs of the series Exodus by Brazilian photographer Mauricio Lima, published on the North American newspaper The New York Times and Pulitzer winner in 2016. Its main objective is to analyze the boundaries between the duty of contemporary photojournalism and the obtainmentof images of refugees. For that, we used as theoretical reference reflections proposed by Appadurai, Bauman, Martínez, Sontag, Shore, Rouillé and Zanforlin. Methodologically, we worked with qualitative research and case study from the analysis of the images and bibliographic research. As a result, it is considered that Lima’s images bring original expressive dimension and seek personal interactions to build profound narratives.

Why Tiempo is under attack

1984 ◽  
Vol 13 (1) ◽  
pp. 21-22
Author(s):  
George Black
Keyword(s):  
New York ◽  
Latin America ◽  
El Salvador ◽  
Central America ◽  
North American ◽  
Armed Forces ◽  
The North ◽  
The Government

‘Those who are not with the government are considered enemies of Honduras, anti-patriots, Communists’ says Tiempo's editor, Manuel Gamero Honduras was until recently an area of calm in the stormy region of Central America. Now, however, its civilian government is hard-pressed by the armed forces who have involved the country in the struggle against the Sandinista government in Nicaragua and the guerrilla fighters in El Salvador. Both Honduras' press and university are coming increasingly under attack, as George Black, a British journalist who is on the staff of the North American Congress on Latin America in New York, here explains.

Sign in / Sign up

Export Citation Format

Share Document