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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Photography and the Falklands Conflict : Homeric heroism in modern warfare

Bingham, Stuart January 2010 (has links)
The Falklands Conflict has always loomed large throughout my adult life. As a young man of 19 years old, I watched the television and read the newspapers with the same degree of excitement and fascination as most of the British population. In the following year, as a direct result of the passion and glory that surrounded the war I joined the British Army as a Royal Military Policeman. It quickly became apparent to myself, if not the military, that this was a poor career choice and that I was never cut out to be a soldier. After a military career lasting no more than a few weeks I went to college and started life as a photographer, joining the Ministry of Defence in the late 1980s. Since then, I have made numerous visits to the Falkland Islands to publicise the work of the soldiers who now defend the islands from any threat of re-invasion. Looking back, it seems that the war was over remarkably quickly, and by modern standards, where the war in Afghanistan is projected to last anything between 10 and 20 years, it was. It has often been described as Britain's last colonial war, the last in a long line of small conflicts that expanded and defended the British Empire. Attitudes to war in the South Atlantic developed in a bubble of patriotism and jingoism that has not been seen since and such attitudes now seem to be forged in imperialism, in a time long past and no longer available to representatives of British culture. However, on a wider stage, the representation of all wars and the men who fight in them has a long history. Each culture has its own way of coming to terms with conflict and death, but in the western world, the origins of the representation of the warrior can be traced back to the Ancient Greeks in general, and Homer in particular. Dr. Jonathan Shay, a psychiatrist with the United States Department of Veteran Affairs has made a compelling argument that breaking the Greek covenant has had lasting implications for the veterans of the Vietnam War. (Shay 1995) This psychoanalytical work has helped provide a model of representation that explains why soldiers are portrayed in the way they are. Without the work of Dr. Shay, I am sure that this thesis would not have taken the course that it has. In pursuing this thesis I have had to accept that there may be implications, perceived or real, for my ongoing work as photographer with the Ministry of Defence. The MoD has in various measures supported this research and to date has made no attempt to direct its course or influence the findings; in fact, at the point of submission, they are unaware of its contents. It is clear, that in this type of research, not all the findings will reflect well on the MoD's past or current working practices, but I believe it is possible for it to learn from the results. My position as an MoD photographer has on the other hand had a positive benefit on the research: I have been able to gain access to archives that have remained closed to others. Hilary Roberts, Head of Photography Collections at the Imperial War Museum, has been very influential in this work and has given me more co-operation and trust than I could have hoped for. She has also allowed me more time to present this work than I could have dared asked for given the nature of the images found in the IWM archive, and that the research spanned the 25 th anniversary celebrations. I remain grateful to Hilary for her unstinting support. Finally, I would like to thank Dr lan Walker for his support and supervisor expertise over far too may years. He has read and re-read this work more times than I care to remember and has remained perennially patient with my inabilities to either type or spell, a problem that has made his job all the more difficult. The research and the writing faltered on several occasions, some more serious than others, but without his skill in getting me to do things that, quite frankly, I really did not want to do, this project would never have been completed. It is to Ian that I hold the deepest debt of gratitude.
2

A history of sealing in the Falkland Islands and Dependencies, 1764-1972

Dickinson, Anthony Bertram January 1987 (has links)
Seven species of seals were hunted in the Falkland Islands and Dependencies in the 18th to 20th centuries. Sealing probably began in the Falkland Islands in 1766 after French settlers arrived in 1764. The potential of an industry was not realized until American whalers arrived by 1774. Continued sealing was prevented by the War of Independence, except for an unsuccessful American attempt to establish a wartime fleet at the islands, shipping oil to London. Postwar economic depression prevented Americans returning, sealing instead being done by British southern whale fishery vessels from 1786. Oil was taken from hair seals, and skins from fur seals. Both were shipped to London. Americans returned by 1792 for fur seal skins for the expanding Canton fur trade. This they subsequently monopolized, British merchants being constrained by the East India Company's trading monopoly. Unregulated killing to supply Canton and London markets virtually exterminated fur seals on the Falkland Islands and South Georgia by the late 18th-early 19th centuries. Increased oil demand in America caused elephant seals to be depleted by the mid 19th century. Discovery of the South Shetland, South Orkney Islands and South Sandwich Islands resulted in stocks on these islands also quickly depleted, particularly to supply an American market. Lack of permanent government and settlement in the Falkland Islands in the 18th and early 19th centuries prevented control being exerted over sealers, although attempts were made by colonists from 1828 and by a British administration from 1833. Lack of patrol vessels prevented enforcement. Sealing legislation was introduced by 1881, but stocks and markets had declined to the point where a domestic sealing industry was difficult to establish. This was exacerbated by Canadian and Chilean pelagic sealing and poaching from 1902 to 1911. Stocks gained some respite during World War 1. Fur sealing was prohibited from 1915 in South Georgia and 1921 in the Falkland Islands, where a sea lion oil industry was developed in 1929. This operated sporadically until 1951. Production costs, fluctuating oil prices, and distance from markets are seen as contributory reasons preventing establishment of an industry. The last sealing licence for the Colony was issued in 1967. Elephant seals increased in the late 19th and early 20th centuries at South Georgia to the point where they could again be utilized. The Compaftia Argentina da Pesca began sealing in 1909, beginning an industry which continued successfully until the licencee left the island after the 1964 season due to the poor economics of whaling. 250,000 seals were taken in a well regulated industry, providing an important contribution to the company's revenue from the island. The numbers of elephant seals and fur seals on South Georgia have increased since whaling and sealing ended. Present anti-sealing concerns, lack of markets, exploitation costs and potential tourist attraction make future sealing in the Falkland Islands and Dependencies unlikely.
3

The role of translation and interpretation in the Shaping of a reader's view of world events - The Press and the Falklands war

Fox Kennedy, Winifred Olivia 01 January 1994 (has links)
No description available.
4

Homo Politicus vs Homo Civicus : hur utformar olika politiska system beslut om militärt våld och vilka militära effekter får det för den militära operationen? / Homo Politicus vs Homo Civicus : how does different political societies form decisions to apply military means of violence and what effects will influence the military operation?

Svensson, Carl-Magnus R January 2009 (has links)
<p>Beslutsfattning om militära våldsmedel varierar med en nations civil-militära mönster. Genom att teoretiskt använda maktbegreppet för att beskriva vilka normativa styrprinciper som formar den civil-militära relationen kan den också beskrivas. Teorin appliceras på Falklandskonflikten och Ubåtsincidenterna i Sverige under tidigt 80-tal. Effekterna som undersöks är tid och uppfattning om det strategiska målet som operationen syftar till.  </p><p>Syftet med uppsatsen har varit att undersöka hur olika typer av relationer mellan civila makthavare och den militära organisationen påverkar utformningen av beslut om militärt våld. Uppsatsen förklarar vilka styrprinciper som ligger bakom hur olika politiska system fattar beslut om militärt våld.</p><p>Resultatet indikerar att maktbegreppet är fruktbart för att kategorisera den civil-militära relationen och därmed beskriva hur olika politiska system fattar beslut om militärt våld. Sverige tenderade till att reglera och överlåta våldsbeslut till den militära aktören, men uppvisade en pragmatisk hållning när beslut brådskade. Storbritanniens dominerande drag var förhandling genom samverkan vilket medförde att direktiv var sällsynta. Reella likheter mellan Storbritanniens och Sveriges civil-militära relation existerade. En skillnad var graden av integration. En formell integration av försvarsmaktsledningen i den politiska ledningen socialiserade den militära aktören till att uppfatta politiska intentioner och internaliserar den att ta hänsyn till politiska konsekvenser av våldsmakten. I Sverige uppstod samverkan mellan aktörerna på basis av <em>ad-hoc</em> vilket medförde att den militära aktören fick stora friheter att genomföra operationen på bekostnad av den civila kontrollen</p> / <p>Decision-making on military violence varies with a nation’s civil-military relation. Applying a theoretical framework that uses the concept of power to determine the normative and ruling principles will allow a model to describe and categorise the civil-military relation. The theory is applied on the Falklands conflict and the Swedish issue of violating submarines in the early eighties. The effects that are examined are time and the apprehension of the conception over the strategic goal for the operation.</p><p>The purpose of this study is to examine how different types of relations between politicians and the military organisation, are affecting the design of the decision process. The study explains what normative and ruling principles that are underlying how different political systems make decisions on military violence.</p><p>The results indicate that the concept of power can be fruitful to categorise the civil-military relation and thereby describe how different political systems makes decisions on military violence. Sweden had an inclination towards governmental regulation and to hand over the decisions to the military operator, but had also a pragmatic attitude when decisions were urgently needed. The dominating inclination in UK during the Falklands conflict was to closely co-ordinate actions through negotiations between the civil and military operators. Actual similarities between the UK and Sweden did exist as well. However, a difference was the level of integration. A formal integration of the military supreme command into the Ministry of Defence will socialise the military operator so that he will detect political intentions and internalize him to take decisions with political considerations. In the case of Sweden co-ordination was run on basis of <em>ad-hoc</em> which gave the military operator large amount of freedom to act at the expense of the civil control</p>
5

Homo Politicus vs Homo Civicus : hur utformar olika politiska system beslut om militärt våld och vilka militära effekter får det för den militära operationen? / Homo Politicus vs Homo Civicus : how does different political societies form decisions to apply military means of violence and what effects will influence the military operation?

Svensson, Carl-Magnus R January 2009 (has links)
Beslutsfattning om militära våldsmedel varierar med en nations civil-militära mönster. Genom att teoretiskt använda maktbegreppet för att beskriva vilka normativa styrprinciper som formar den civil-militära relationen kan den också beskrivas. Teorin appliceras på Falklandskonflikten och Ubåtsincidenterna i Sverige under tidigt 80-tal. Effekterna som undersöks är tid och uppfattning om det strategiska målet som operationen syftar till.   Syftet med uppsatsen har varit att undersöka hur olika typer av relationer mellan civila makthavare och den militära organisationen påverkar utformningen av beslut om militärt våld. Uppsatsen förklarar vilka styrprinciper som ligger bakom hur olika politiska system fattar beslut om militärt våld. Resultatet indikerar att maktbegreppet är fruktbart för att kategorisera den civil-militära relationen och därmed beskriva hur olika politiska system fattar beslut om militärt våld. Sverige tenderade till att reglera och överlåta våldsbeslut till den militära aktören, men uppvisade en pragmatisk hållning när beslut brådskade. Storbritanniens dominerande drag var förhandling genom samverkan vilket medförde att direktiv var sällsynta. Reella likheter mellan Storbritanniens och Sveriges civil-militära relation existerade. En skillnad var graden av integration. En formell integration av försvarsmaktsledningen i den politiska ledningen socialiserade den militära aktören till att uppfatta politiska intentioner och internaliserar den att ta hänsyn till politiska konsekvenser av våldsmakten. I Sverige uppstod samverkan mellan aktörerna på basis av ad-hoc vilket medförde att den militära aktören fick stora friheter att genomföra operationen på bekostnad av den civila kontrollen / Decision-making on military violence varies with a nation’s civil-military relation. Applying a theoretical framework that uses the concept of power to determine the normative and ruling principles will allow a model to describe and categorise the civil-military relation. The theory is applied on the Falklands conflict and the Swedish issue of violating submarines in the early eighties. The effects that are examined are time and the apprehension of the conception over the strategic goal for the operation. The purpose of this study is to examine how different types of relations between politicians and the military organisation, are affecting the design of the decision process. The study explains what normative and ruling principles that are underlying how different political systems make decisions on military violence. The results indicate that the concept of power can be fruitful to categorise the civil-military relation and thereby describe how different political systems makes decisions on military violence. Sweden had an inclination towards governmental regulation and to hand over the decisions to the military operator, but had also a pragmatic attitude when decisions were urgently needed. The dominating inclination in UK during the Falklands conflict was to closely co-ordinate actions through negotiations between the civil and military operators. Actual similarities between the UK and Sweden did exist as well. However, a difference was the level of integration. A formal integration of the military supreme command into the Ministry of Defence will socialise the military operator so that he will detect political intentions and internalize him to take decisions with political considerations. In the case of Sweden co-ordination was run on basis of ad-hoc which gave the military operator large amount of freedom to act at the expense of the civil control
6

Poslední vojenská diktatura v Argentině v letech 1976 - 1983 / The last military dictatorship in Argentina in the years 1976 - 1983

Rosenkrancová, Eva January 2014 (has links)
(in English) The thesis discusses the government of the most recent military dictatorship in Argentina in 1976-1983. The first chapter defines the basic concepts that are important for the proper interpretation of the work and provides a brief overview of the political developments and the situation in the country in the 20th century that preceded the last military coup. The main part of the thesis gives the characteristics of the period 1976-1983, that is rise to power, action and fall of the military dictatorship with a reflection of the development of relations with the USA and Argentina in this period of time. It also delivers a view of the Falklands War, which accelerated the transition from dictatorship to democracy in Argentina. The work also includes insight into the present in the context of the impact of the seven-year military junta to Argentine society as well as the question of the future of the islands, in the context of the continuing recognition of Argentina's claims to sovereignty over the islands.
7

Climbing the Mountain of Conflict: Margaret Thatcher's Falklands Crisis

Waldman, Benjamin F 01 January 2015 (has links)
Early in her Prime Ministership, Margaret Thatcher fought an unlikely diversionary war far from home for the ownership of the Falkland Islands. The Islands lie off of Argentina’s coast about 8,000 miles from London, but have been subject to Britain’s rule since 1836. In April 1982, hoping to distract from domestic political and economic turmoil, Argentina’s military dictatorship ordered a surprise invasion of the Islands. Thatcher, Britain’s first female Prime Minister, responded in full force. By early May, a British fleet reached the Islands. By June, despite American efforts to stop a war between its allies, Britain launched an assault on the Islands and took them back by force. Thatcher’s victory propelled her to immense popularity in late-1982 and 1983, and the Argentine dictatorship’s defeat gave life to a people’s revolt that quickly ended the regime and decades of military leadership. This thesis examines Thatcher’s leadership in April 1982, before Britain launched its retaliatory invasion of the Islands. It seeks to answer how Thatcher managed to make the war possible and popular in three key arenas: with her own cabinet and government, with the United States and the United Nations, and ultimately with the British public. This study operates on the idea that the war served as an intentional diversion for Thatcher, who had struggled domestically as Prime Minister up until the Falklands Crisis. Utilizing newly released archival documents from the Thatcher government, this study shows the Prime Minister never had any interest in avoiding war, undermining any potential for peace as it emerged.
8

A política externa brasileira frente ao conflito das Falklands/Malvinas (1982)

Espósito Neto, Tomaz 24 August 2006 (has links)
Made available in DSpace on 2016-04-27T19:31:24Z (GMT). No. of bitstreams: 1 Tomaz Esposito Neto.pdf: 1186365 bytes, checksum: e6020e106fe7e941fc5845b974a65a56 (MD5) Previous issue date: 2006-08-24 / Em 04 de abril de 1982, as forças armadas argentinas empreenderam uma ação militar para a (re)conquista das ilhas Falklands/Malvinas, iniciando um conflito bélico entre a Grã Bretanha e a Argentina, que durou 74 dias, com a vitória das tropas reais britânicas. A ação argentina surpreendeu a comunidade internacional, e, colocou fim as negociações entre o Reino Unido e a Argentina sobre a soberania do arquipélago, realizadas sob os auspícios da ONU. A evolução do conflito anglo-argentino colocou a diplomacia brasileira em uma posição delicada, pois a guerra envolvia dois países importantes nas relações exteriores brasileiras. De um lado, a economia brasileira dependia do mercado, em especial o financeiro, do Reino Unido. Por outro, a Argentina, desde a resolução da questão hidroelétrica de Itaipu-Corpus em 1979, era um país considerado chave nas relações exteriores brasileiras. Diante deste quadro, o objetivo do presente trabalho é contextualizar e analisar a atuação internacional do Brasil frente ao conflito das Falklands/Malvinas de 1982. Analisando, através do conflito, alguns elementos da política externa brasileira do Governo Figueiredo (1979-1984)
9

Estratigrafia magnética e magnetismo ambiental do sítio DSDP-511 (Platô das Falklands) durante o limite Barremiano-Aptiano / Magnetostratigraphy and environmental magnetism of the site DSDP-511 (Falkland Plateau) during the Barremian-Aptian boundery

Carmo, Janine Araujo do 25 October 2017 (has links)
O Cretáceo inferior é caracterizado por mudanças drásticas em todos os envelopes terrestres, envolvendo desde variações geodinâmicas a importantes mudanças paleoclimáticas. Entretanto, há poucos registros desses eventos no hemisfério sul, sendo o DSDP-511 o principal deles. Com objetivo de gerar melhores vínculos temporais para os registros do Cretáceo Inferior no hemisfério sul, foram realizados estudos paleomagnéticos e de magnetismo ambiental em alta resolução espacial em uma secção do sítio DSDP-511 (núcleos 58 e 59), a qual corresponde ao intervalo entre 508,77 a 523,94 mbsf (meters below sea floor) e abrange os estágios Barremiano e Aptiano. A compreensão dos eventos paleoclimáticos neste sítio não é trivial, uma vez que, além de ambiguidade nas idades inferidas pela bioestratigrafia, apenas parte do evento de anoxia oceânica OAE 1a está registrada devido a uma lacuna de amostragem. Foram identificados dois principais portadores magnéticos através da análise de curvas de aquisição e desmagnetização de magnetização remanente anisterética (ARM) e magnetização remanente isotérmica (IRM). O mineral de baixa corecividade é a magnetita, confirmada a partir da desmagnetização de IRM triaxial. Sua origem é provavelmente detrítica. O portador de alta coercividade foi interpretado como hematita. A contribuição relativa dos portadores magnéticos apresentou uma variação acentuada no intervalo entre 512 e 514 mbsf, sendo manifestada através de um pico em todos os parâmetros de magnetismo ambiental. Esta variação está associada também à maior concentração de minerais magnéticos neste intervalo e coincide com um marcado aumento na temperatura da superfície dos oceanos. Após desmagnetização progressiva e identificação da componente magnética característica foram definidas duas zonas de polaridade normal e uma zona de polaridade reversa (518,9 e 518,16 mbsf). Além disso, foi definida uma zona discreta de polaridade reversa em 509,20 mbsf. Os resultados encontrados apresentam diferenças significativas quando comparadas com estudos anteriores no mesmo testemunho. Uma datação Re-Os em folhelhos negros de 125,3 ± 2,2 Ma entre 519,01 e 519,40 mbsf foi obtida recentemente e forneceu um vínculo absoluto de idade para o intervalo estudado. O padrão de reversões encontrado foi compatível com a presença dos chrons M0r e ISEA. O modelo de idades proposto permite reposicionar o evento OAE 1a entre as profundidades 513,5 a 518 mbsf, incluindo a parte não recuperada do testemunho. Esta interpretação também compatível com dados de TOC e de 13C obtidos recentemente por outros autores. / The lower Cretaceous is characterized by drastic changes in the Earth, from geodynamic variations to important paleoclimatic changes. However, there are few records of these events in the southern hemisphere, the DSDP-511 being the most comprehensive one. In order to provide better temporal constraints for the lower Cretaceous records in the southern hemisphere, paleomagnetic and high-resolution environmental magnetism studies were performed in a section of the DSDP-511 site (cores 58 and 59), which corresponds to the interval between 508.77 to 523.94 mbsf (meters below sea floor) and covers the Barremian and Aptian stages. The correct assessment of paleoclimatic events at this site is not trivial because, in addition to the ambiguity at the ages inferred by biostratigraphy, only part of the OAE 1a (oceanic anoxic event) was recovered. Two main magnetic carriers were identified through the analysis of acquisition and demagnetization of anhysteretic remanent magnetization (ARM) and isothermal remanent magnetization (IRM) curves. The low coercivity mineral is magnetite, as attested by triaxial IRM demagnetization. Its origin is likely detrital. The high coercivity carrier was interpreted as hematite. The relative contribution of magnetic carriers has a strong variation in the interval between 512 and 514 mbsf, being manifested by a peak in all parameters of environmental magnetism. This variation is also associated with the higher concentration of magnetic minerals and coincides with a marked increase in the sea surface temperature in this interval. After stepwise demagnetization and identification of the characteristic magnetic component, two zones of normal polarity and a zone of reverse polarity (518.9 and 518.16 mbsf) were defined. In addition, a discrete zone of reverse polarity was defined at 509.20 mbsf. The results obtained present significant differences when compared with previous studies in the same core. A Re-Os dating on black shales of 125.3 ± 2.2 Ma between 519.01 and 519.40 mbsf was obtained recently and provided an absolute constraint onto which the polarity zones could be matched. The pattern of reversions found is compatible with the presence of chrons M0r and ISEA. The proposed age model allows repositioning the OAE 1a event between depths 513.5 to 518 mbsf in the core and overlap the unrecovered part. This interpretation is also compatible with TOC and 13C data recently obtained by other authors.
10

Estratigrafia magnética e magnetismo ambiental do sítio DSDP-511 (Platô das Falklands) durante o limite Barremiano-Aptiano / Magnetostratigraphy and environmental magnetism of the site DSDP-511 (Falkland Plateau) during the Barremian-Aptian boundery

Janine Araujo do Carmo 25 October 2017 (has links)
O Cretáceo inferior é caracterizado por mudanças drásticas em todos os envelopes terrestres, envolvendo desde variações geodinâmicas a importantes mudanças paleoclimáticas. Entretanto, há poucos registros desses eventos no hemisfério sul, sendo o DSDP-511 o principal deles. Com objetivo de gerar melhores vínculos temporais para os registros do Cretáceo Inferior no hemisfério sul, foram realizados estudos paleomagnéticos e de magnetismo ambiental em alta resolução espacial em uma secção do sítio DSDP-511 (núcleos 58 e 59), a qual corresponde ao intervalo entre 508,77 a 523,94 mbsf (meters below sea floor) e abrange os estágios Barremiano e Aptiano. A compreensão dos eventos paleoclimáticos neste sítio não é trivial, uma vez que, além de ambiguidade nas idades inferidas pela bioestratigrafia, apenas parte do evento de anoxia oceânica OAE 1a está registrada devido a uma lacuna de amostragem. Foram identificados dois principais portadores magnéticos através da análise de curvas de aquisição e desmagnetização de magnetização remanente anisterética (ARM) e magnetização remanente isotérmica (IRM). O mineral de baixa corecividade é a magnetita, confirmada a partir da desmagnetização de IRM triaxial. Sua origem é provavelmente detrítica. O portador de alta coercividade foi interpretado como hematita. A contribuição relativa dos portadores magnéticos apresentou uma variação acentuada no intervalo entre 512 e 514 mbsf, sendo manifestada através de um pico em todos os parâmetros de magnetismo ambiental. Esta variação está associada também à maior concentração de minerais magnéticos neste intervalo e coincide com um marcado aumento na temperatura da superfície dos oceanos. Após desmagnetização progressiva e identificação da componente magnética característica foram definidas duas zonas de polaridade normal e uma zona de polaridade reversa (518,9 e 518,16 mbsf). Além disso, foi definida uma zona discreta de polaridade reversa em 509,20 mbsf. Os resultados encontrados apresentam diferenças significativas quando comparadas com estudos anteriores no mesmo testemunho. Uma datação Re-Os em folhelhos negros de 125,3 ± 2,2 Ma entre 519,01 e 519,40 mbsf foi obtida recentemente e forneceu um vínculo absoluto de idade para o intervalo estudado. O padrão de reversões encontrado foi compatível com a presença dos chrons M0r e ISEA. O modelo de idades proposto permite reposicionar o evento OAE 1a entre as profundidades 513,5 a 518 mbsf, incluindo a parte não recuperada do testemunho. Esta interpretação também compatível com dados de TOC e de 13C obtidos recentemente por outros autores. / The lower Cretaceous is characterized by drastic changes in the Earth, from geodynamic variations to important paleoclimatic changes. However, there are few records of these events in the southern hemisphere, the DSDP-511 being the most comprehensive one. In order to provide better temporal constraints for the lower Cretaceous records in the southern hemisphere, paleomagnetic and high-resolution environmental magnetism studies were performed in a section of the DSDP-511 site (cores 58 and 59), which corresponds to the interval between 508.77 to 523.94 mbsf (meters below sea floor) and covers the Barremian and Aptian stages. The correct assessment of paleoclimatic events at this site is not trivial because, in addition to the ambiguity at the ages inferred by biostratigraphy, only part of the OAE 1a (oceanic anoxic event) was recovered. Two main magnetic carriers were identified through the analysis of acquisition and demagnetization of anhysteretic remanent magnetization (ARM) and isothermal remanent magnetization (IRM) curves. The low coercivity mineral is magnetite, as attested by triaxial IRM demagnetization. Its origin is likely detrital. The high coercivity carrier was interpreted as hematite. The relative contribution of magnetic carriers has a strong variation in the interval between 512 and 514 mbsf, being manifested by a peak in all parameters of environmental magnetism. This variation is also associated with the higher concentration of magnetic minerals and coincides with a marked increase in the sea surface temperature in this interval. After stepwise demagnetization and identification of the characteristic magnetic component, two zones of normal polarity and a zone of reverse polarity (518.9 and 518.16 mbsf) were defined. In addition, a discrete zone of reverse polarity was defined at 509.20 mbsf. The results obtained present significant differences when compared with previous studies in the same core. A Re-Os dating on black shales of 125.3 ± 2.2 Ma between 519.01 and 519.40 mbsf was obtained recently and provided an absolute constraint onto which the polarity zones could be matched. The pattern of reversions found is compatible with the presence of chrons M0r and ISEA. The proposed age model allows repositioning the OAE 1a event between depths 513.5 to 518 mbsf in the core and overlap the unrecovered part. This interpretation is also compatible with TOC and 13C data recently obtained by other authors.

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