Pre-Mesozoic origin and paleogeography of blocks in the Caribbean, South Appalachian and West African domains and their impact on the post “variscan” evolution

2013 ◽  
Vol 184 (1-2) ◽  
pp. 5-20 ◽  
Author(s):  
Michel Villeneuve ◽  
Boris Marcaillou
Keyword(s):  
West Africa ◽  
Atlantic Ocean ◽  
West African ◽  
Large Area ◽  
Tectonic Event ◽  
Western Sahara ◽  
The North ◽  
Gondwana Margin ◽  
The Caribbean ◽  
North American Craton

Abstract New geodynamical data from West Africa bring consistent informations on the pre-Mesozoic reconstruction within a large area running from the western Sahara to the Colombian cordillera. These new data support a Neoproterozoic Ocean (WANO) between the Amazonian (AMC) and West African (WAC) cratons previously to the Iapetus and Rheic oceans. We delineate 31 blocs detached from the surrounding three continents: NAC (North American Craton), AMC and WAC. 7 came from the WAC margin, 7 from the NAC, 6 from the AMC and 11 from an intermediate volcano sedimentary domain (COB) built on a 1200–1000 Ma oceanic crust. These imbricated blocks formed a tight mosaic by the Hercynian/Alleghanian tectonic event which gave way to the Pangea super-continent. But, during the Atlantic Ocean opening these blocks began to move. They were separated by new oceanic basins. However, previously to the Pangea, blocks from the COB domain formed two sets of garlands located on the northwestern Gondwana margin. The northern one moved to the North until the Silurian to collide the NAC (Taconic tectonic event) meanwhile the southern one remains on the Gondwana margin. All together were gathered by the Carboniferous/Permian time. Then, the framework for the opening of the Atlantic Ocean was not totally disconnected from the “Variscan” collage and many variscan weakness zones were re-used as initial breaking zones. Beyond this tectonic impact, the pre-mesozoic assemblage allows us to compare this “Caribbean” island arc with another one: the Indonesian “Banda” arc. Thus, West Africa is a geological key area for correlations between the Caribbean, the Appalachian, the Brazilian “Nordeste” and the West European domains and for the understanding of the Atlantic Ocean opening process.

scholarly journals Modelling the spread and connectivity of waterborne marine pathogens: the case of PaV1 in the Caribbean

2014 ◽  
Vol 72 (suppl_1) ◽  
pp. i139-i146 ◽  
Author(s):  
Andrew S. Kough ◽  
Claire B. Paris ◽  
Donald C. Behringer ◽  
Mark J. Butler
Keyword(s):  
Field Experiments ◽  
Significant Risk ◽  
Large Area ◽  
Larval Stages ◽  
The North ◽  
Risk Of Mortality ◽  
Rapid Spread ◽  
Waterborne Transmission ◽  
Juvenile Stages ◽  
The Caribbean

AbstractThe PaV1 virus infects spiny lobsters (Panulirus argus) throughout most of the Caribbean, where its prevalence in adult lobsters can reach 17% and where it poses a significant risk of mortality for juveniles. Recent studies indicate that vertical transmission of the virus is unlikely and PaV1 has not been identified in the phyllosoma larval stages. Yet, the pathogen appears subclinically in post-larvae collected near the coast, suggesting that lobster post-larvae may harbour the virus and perhaps have aided in the dispersal of the pathogen. Laboratory and field experiments also confirm the waterborne transmission of the virus to post-larval and early benthic juvenile stages, but its viability in the water column may be limited to a few days. Here, we coupled Lagrangian modelling with a flexible matrix model of waterborne and post-larval-based pathogen dispersal in the Caribbean to investigate how a large area with complex hydrology influences the theoretical spread of disease. Our results indicate that if the virus is waterborne and only viable for a few days, then it is unlikely to impact both the Eastern and Northwestern Caribbean, which are separated by dispersal barriers. However, if PaV1 can be transported between locations by infected post-larvae, then the entire Caribbean becomes linked by pathogen dispersal with higher viral prevalence in the North. We identify possible regions from which pathogens are most likely to spread, and highlight Caribbean locations that function as dispersal “gateways” that could facilitate the rapid spread of pathogens into otherwise isolated areas.

The Royal Navy and West Africa, 1843-1857

2008 ◽  
pp. 133-168
Author(s):  
Mark C. Hunter
Keyword(s):  
West Africa ◽  
Free Trade ◽  
West African ◽  
Economic Interest ◽  
Royal Navy ◽  
The West ◽  
The North ◽  
West African Coast ◽  
African Coast ◽  
American Diplomacy

This chapter analyses the British naval policies concerning West Africa between 1843 and 1857. During this period, Britain sought to encourage legitimate commerce and curtail slavery for its own economic interest, while domestically America feared the British domination of the West African coast. As such, suspicion and mistrust was rife between the two nations, and is in great detail via the abolitionist activity in the North of England; the actions of free traders and slavers; Royal Navy operations; the competition for trade between Britain and France; Commodore Charles Hotham’s slavery suppressing naval strategy; British free trade treaties; and the naval methods of enforcing British goals. It concludes in 1857, with British interests torn between strategic naval aims and domestic pressures, and British and American diplomacy still tense over West African policies.

Some social and phenomenological characteristics of psychotic immigrants

1981 ◽  
Vol 11 (2) ◽  
pp. 289-302 ◽  
Author(s):  
Roland Littlewood ◽  
Maurice Lipsedge
Keyword(s):  
Retrospective Study ◽  
West Africa ◽  
Ethnic Group ◽  
West Indian ◽  
Married Women ◽  
West African ◽  
High Rate ◽  
Psychiatric Unit ◽  
The West ◽  
The Caribbean

SynopsisVarious studies have shown: (i) increased rates of psychoses in immigrants to Britain, and a particularly high rate of schizophrenia in the West Indian- and West African-born; and (ii) a greater proportion of atypical psychoses in immigrants. A retrospective study of psychotic inpatients from a London psychiatric unit demonstrated increased rates of schizophrenia in patients from the Caribbean and West Africa. These patients included a high proportion of those with paranoid and religious phenomenology, those with frequent changes of diagnosis, formal admissions, and married women. The West Indian-born had been in Britain for nearly 10 years before first seeing a psychiatrist and, if they had an illness with religious symptomatology, were likely to have been in hospital for only 3 weeks. Rates of schizophrenia without paranoid phenomenology were similar in each ethnic group. It is suggested that the increase in the diagnosis of schizophrenia in the West Indian- born, and possibly in the West African-born, may be due in part to the occurrence of acute psychotic reactions which are diagnosed as schizophrenia.

Social Administration of the Kru. A Preliminary Survey

Africa ◽  
1937 ◽  
Vol 10 (1) ◽  
pp. 75-96 ◽  
Author(s):  
H. Scudder Mekeel
Keyword(s):  
West Africa ◽  
West African ◽  
Preliminary Survey ◽  
The South ◽  
North West ◽  
North East ◽  
The North ◽  
Archaeological Work ◽  
Opening Paragraph ◽  
Physical Type

Opening ParagraphThe Kru, a West African Negro group, inhabit the central and southern part of Liberia. They are surrounded by the Basa peoples to the north-west, by the Grebo to the south-east and by the Putu to the north-east. The informant, Thomas Tarbour (Sieh Tagbweh), from whom the following material was derived, was a native of Grand Cess (Siglipo), a large coast town near the border of the Grebo country. The Kru, along with other related groups in that part of West Africa, have a tradition of having migrated from far to the north-east. The physical type is that of the short, stocky Bush negro. No archaeological work has been done in the region, and such ethnological material as has been collected is a mere beginning.

scholarly journals Remote biomass burning dominates southern West African air pollution during the monsoon

2019 ◽  
Vol 19 (24) ◽  
pp. 15217-15234 ◽  
Author(s):  
Sophie L. Haslett ◽  
Jonathan W. Taylor ◽  
Mathew Evans ◽  
Eleanor Morris ◽  
Bernhard Vogel ◽  
...  
Keyword(s):  
Air Pollution ◽  
West Africa ◽  
Atlantic Ocean ◽  
Biomass Burning ◽  
West African ◽  
Small Scale ◽  
High Background ◽  
Accumulation Mode ◽  
Aerosol Loading ◽  
Biomass Burning Aerosol

Abstract. Vast stretches of agricultural land in southern and central Africa are burnt between June and September each year, which releases large quantities of aerosol into the atmosphere. The resulting smoke plumes are carried west over the Atlantic Ocean at altitudes between 2 and 4 km. As only limited observational data in West Africa have existed until now, whether this pollution has an impact at lower altitudes has remained unclear. The Dynamics-aerosol-chemistry-cloud interactions in West Africa (DACCIWA) aircraft campaign took place in southern West Africa during June and July 2016, with the aim of observing gas and aerosol properties in the region in order to assess anthropogenic and other influences on the atmosphere. Results presented here show that a significant mass of aged accumulation mode aerosol was present in the southern West African monsoon layer, over both the ocean and the continent. A median dry aerosol concentration of 6.2 µg m−3 (standard temperature and pressure, STP) was observed over the Atlantic Ocean upwind of the major cities, with an interquartile range from 5.3 to 8.0 µg m−3. This concentration increased to a median of 11.1 µg m−3 (8.6 to 15.7 µg m−3) in the immediate outflow from cities. In the continental air mass away from the cities, the median aerosol loading was 7.5 µg m−3 (5.9 to 10.5 µg m−3). The accumulation mode aerosol population over land displayed similar chemical properties to the upstream population, which implies that upstream aerosol is a significant source of aerosol pollution over the continent. The upstream aerosol is found to have most likely originated from central and southern African biomass burning. This demonstrates that biomass burning plumes are being advected northwards, after being entrained into the monsoon layer over the eastern tropical Atlantic Ocean. It is shown observationally for the first time that they contribute up to 80 % to the regional aerosol loading in the monsoon layer over southern West Africa. Results from the COSMO-ART (Consortium for Small-scale Modeling – Aerosol and Reactive Trace gases) and GEOS-Chem models support this conclusion, showing that observed aerosol concentrations over the northern Atlantic Ocean can only be reproduced when the contribution of transported biomass burning aerosol is taken into account. As a result, the large and growing emissions from the coastal cities are overlaid on an already substantial aerosol background. Simulations using COSMO-ART show that cloud droplet number concentrations can increase by up to 27 % as a result of transported biomass burning aerosol. On a regional scale this renders cloud properties and precipitation less sensitive to future increases in anthropogenic emissions. In addition, such high background loadings will lead to greater pollution exposure for the large and growing population in southern West Africa. These results emphasise the importance of including aerosol from across country borders in the development of air pollution policies and interventions in regions such as West Africa.

Liberia

2020 ◽  
Author(s):  
Marius Schneider ◽  
Vanessa Ferguson
Keyword(s):  
West Africa ◽  
Atlantic Ocean ◽  
Sierra Leone ◽  
North Atlantic ◽  
Ivory Coast ◽  
North Atlantic Ocean ◽  
Capital City ◽  
The North ◽  
The North Atlantic

Liberia is situated in the southern part of West Africa on the North Atlantic Ocean, bordered by Sierra Leone, Guinea, and Ivory Coast, covering an area of 111,369 square kilometres (km) with a population of 4,958,454. The majority of the population live in the Montserrado county and home to the capital city of Monrovia, with approximately 25 per cent of the Liberian population living in greater Monrovia. Monrovia is the capital and most populous city in Liberia and has the largest artificial port in West Africa. Typically, business hours are Monday to Friday from 0800 to 1700 with banks closing at 1500. The official currency of Liberia is the Liberian dollar (LRD).

The Sacred Language of the Abakuá

2020 ◽  
pp. 1-368
Author(s):  
Lydia Cabrera
Keyword(s):  
West Africa ◽  
West African ◽  
Original Material ◽  
Historical Figures ◽  
The Caribbean ◽  
Lydia Cabrera ◽  
African Institution

This chapter is a translation of the introduction and over 6,000 entries of Abakuá ritual jargon created by Lydia Cabrera from 1938–1959 in Havana and Matanzas, Cuba. Many entries have new commentaries by living Abakuá specialists to clarify obscure issues in the original material. The entries refer to the foundation of Abakuá in West Africa centuries ago, with reference to historical figures in the port of Calabar. They also refer to important Abakuá specialists in Cuba and the adaptation of this West African institution to the Caribbean context.

On vortices initiated over West Africa and their impact on North Atlantic tropical cyclones

2020 ◽  
Author(s):  
Jean-Philippe Duvel
Keyword(s):  
West Africa ◽  
Atlantic Ocean ◽  
North Atlantic ◽  
West African ◽  
Synoptic Scale ◽  
Low Level ◽  
Potential Index ◽  
West African Coast ◽  
African Coast ◽  
Low Levels

AbstractUsing 38 years of the ERA Interim dataset, an objective tracking approach is used to analyze the origin, characteristics and cyclogenesis efficiency (CE) of synoptic-scale vortices initiated over West Africa and the Atlantic Ocean. Many vortex tracks initiated near the coast or over the ocean result from a vertical expansion of a “primary” vortex track that was initiated earlier over West Africa. Low-level (850hPa) primary vortices are initiated mainly in July near the Hoggar mountains (5°E, 24°N), while mid-level (700 hPa) primary vortices are initiated mainly in August-September near Guinea highlands (10°W, 10°N). The CE of all these vortices is about 10% in July and 30% in August. The average CE is however smaller for low-level “Hoggar” vortices because they peak in July when the cyclogenesis potential index of the Atlantic Ocean is weak. Seasonal and interannual modulations of the cyclogenesis is related more to this index than to the number of vortices crossing the West African coast. Cyclogenesis is nearly equally distributed between the coast and 60°W, but the part of the cyclogenesis due to vortices initiated over West Africa decreases from 80% near the coast to about 30% at 60°W. The most probable delay between the vortex vertical expansion and cyclogenesis is 2 days, but it can be up to 10 days. This analysis also confirms previous results, such as the larger CE for vortices extending at low-levels over the continent at 10°N, or the delayed and therefore west-shifted cyclogenesis of low-level “Hoggar” vortices.

Islam and Trade in the Bilād AL-Sūdān, Tenth-Eleventh Century A.D.

1983 ◽  
Vol 24 (4) ◽  
pp. 431-440 ◽  
Author(s):  
Michael Brett
Keyword(s):  
Twentieth Century ◽  
West Africa ◽  
Eleventh Century ◽  
West African ◽  
Legal Basis ◽  
African Society ◽  
Western Sahara ◽  
Legal Opinions ◽  
The Law ◽  
Muslim Communities

Two fatwā-s or legal opinions of the jurist al-Qābisī at Qayrawān about the year A.D. 1000 show the way in which the Law of Islam was used to protect the Muslim against the hazards of trans-Saharan trade with the Bilād al-Sūdan. Trade was to be conducted as far as possible in accordance with the Law, and approval was given to the establishment of Muslim communities in the Bilād al-Sūdān under the authority of a nāzir or ‘watchman’, with the consent of the pagan king of the country. The formation of Muslim communities on this legal basis, and their incorporation into the pattern of West African society, were important for the subsequent character of Islam in West Africa. Meanwhile, among the ‘stateless’ Berber peoples of the Western Sahara, the doctrines of the Malikite school were subject to a different interpretation by Ibn Yasln, which came into open conflict with the views of al-Qābisī when the Almoravids sacked the Muslim city of Awdaghast for submitting to the pagan king of Ghana. This conflict of attitudes to paganism remained a feature of West African Islam down to the twentieth century.

Mbadamassi of Lagos: A Soldier for King and Kaiser, and a Deportee to German South West Africa

2009 ◽  
Vol 2 (1) ◽  
pp. 103-124
Author(s):  
Jan-Bart Gewald
Keyword(s):  
West Africa ◽  
South African ◽  
Military Service ◽  
West African ◽  
The South ◽  
The West ◽  
The North ◽  
German Army ◽  
South West ◽  
South West Africa

Abstract In 1915 troops of the South African Union Defence Force invaded German South West Africa, present day Namibia. In the north of the territory the South African forces captured an African soldier serving in the German army named Mbadamassi. Upon his capture Mbadamassi demanded to be released and claimed that he was a British national from Nigeria. In addition, he stated that he had served in the West African Frontier Force, and that he had been shanghaied into German military service in Cameroon. Furthermore, whilst serving in the German army in Cameroon, Mbadamassi claimed that he had participated in a mutiny, and that, as a consequence, he had been deported to GSWA. The article covers the remarkable military career of the African soldier, Mbadamassi, who between 1903 and 1917 served both the King of the British Empire as well as the Kaiser of the German Empire. In so doing, the article sheds light on the career of an individual African soldier serving in three colonial armies; the West African Frontier Force, the Schutztruppe in Cameroon, and the Schutztruppe in GSWA. The article argues that beyond the fact that colonial armies were institutions of repression, they also provided opportunity for those willing or condemned to serve within their ranks. Furthermore the article provides some indication as to the extent of communication that existed between colonial subjects in the separate colonies of Africa at the time. En 1915, les troupes de l'Union de l'Afrique du Sud ont envahi l'Afrique du Sud-Ouest allemande, l'actuelle Namibie. Dans le Nord du territoire, les forces sud-africaines ont capturé un soldat africain servant dans l'armée allemande nommé Mbadamassi. Celui-ci exigea d'être libéré et revendiqua être un Britannique du Nigeria. De plus, il déclara avoir servi dans la West African Frontier Force et avoir été enrôlé de force dans l'armée allemande au Cameroun. En outre, pendant qu'il servait dans l'armée allemande au Cameroun, Mbadamassi a prétendu avoir pris part à une mutinerie, ce qui avait conduit à sa déportation vers l'Afrique du Sud-Ouest allemande. Cet article couvre la remarquable carrière militaire du soldat africain Mbadamassi, qui, entre 1903 et 1917, a servi à la fois le roi de l'empire britannique et le Kaiser de l'empire allemand. Ainsi, l'article éclaire sur la carrière individuelle d'un soldat africain servant dans trois armées coloniales; la West African Frontier Force, le Schutztruppe au Cameroun et le Schutztruppe en Afrique du Sud-Ouest allemande. L'article soutient qu'au-delà du fait que les armées coloniales étaient des institutions de répression, elles ont aussi offert la possibilité à ceux qui le voulaient ou ceux qui y étaient condamnés de servir dans leurs rangs. En outre, l'article fournit une indication sur l'étendue de la communication qui a existé entre les sujets coloniaux dans les colonies d'Afrique séparées de l'époque.

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