Geochemical and Sr, Nd, Pb isotope investigation of the New Caledonia ophiolite

The New Caledonia ophiolite hosts one of the largest obducted mantle section in the world, hence providing a unique insight for the study of upper mantle processes. These mantle rocks belong to an “atypical” ophiolitic sequence, which is dominated by refractory harzburgites but it also includes minor spinel and plagioclase lherzolites. Upper crust is notably absent in the ophiolite, with the exception of some mafic-ultramafic cumulates cropping out in the southern part of the island. Although the New Caledonia ophiolite has been under investigation for decades, its ultra-depleted nature has made its characterization an analytical challenge, so that few trace element data are available, while isotopic data are completely missing. In this thesis a comprehensive geochemical study (major, trace element and Sr-Nd-Pb isotopes) of the peridotites and the associated intrusive mafic rocks from the New Caledonia ophiolite has been carried out. The peridotites are low-strain tectonites showing porphyroclastic textures. Spinel lherzolites are undepleted lithotypes, as attested by the presence of 7-8 vol% of Na2O and Al2O3-rich clinopyroxene (up to 0.5 wt% Na2O; 6.5 wt% Al2O3), Fo content of olivine (88.5-90.0 mol%) and low Cr# of spinel (13-17). Conversely, harzburgites display a refractory nature, proven by the remarkable absence of primary clinopyroxene, very high Fo content in olivine (90.9-92.9 mol%), high Mg# in orthopyroxene (89.8-94.2) and Cr# in spinel (39-71). REE contents show abyssal-type patterns for spinel lherzolites, while harzburgites display U-shaped patterns, typical of fore-arc settings. Spinel lherzolites REE compositions are consistent with relatively low degree (8-9%) of fractional melting of a DMM source, starting in the garnet stability field. Conversely, REE models for harzburgites indicate high melting degrees (20-25%) of a DMM mantle source under spinel faies conditions, consistent with hydrous melting in forearc setting. Plagioclase lherzolites exhibit melt impregnation microtextures, Cr- and TiO2-enriched spinels and REE, Ti, Y, Zr progressive increase with respect to spinel lherzolites. Impregnation models indicate that plagioclase lherzolites may derive from spinel lherzolites by entrapment of highly depleted MORB melts in the shallow oceanic lithosphere. Mafic intrusives are olivine gabbronorites with a very refractory composition, as attested by high Fo content of olivine (87.3-88.9 mol.%), very high Mg# of clinopyroxene (87.7-92.2) and extreme anorthitic content of plagioclase (An = 90-96 mol%). The high Mg#, low TiO2 concentrations in pyroxenes and the anorthitic composition of plagioclase point out an origin from ultra-depleted primitive magmas in a convergent setting. Geochemical trace element models show that the parental melts of gabbronorites are primitive magmas with striking depleted compositions, bearing only in part similarities with the primitive boninitic melts of Bonin Islands. The first Sr, Nd and Pb isotope data obtained for the New Caledonia ophiolite highlight the presence of DM mantle source variably modified by different processes. Nd-Sr-Pb isotopic ratios for the lherzolites (+6.98≤epsilon Ndi≤+10.97) indicate a DM source that suffered low-temperature hydrothermal reactions. Harzburgites are characterized by a wide variation of Sr, Nd and Pb isotopic values, extending from DM-type to EM2 compositions (-0.82≤ epsilon Ndi≤+17.55), suggesting that harzburgite source was strongly affected by subduction-related processes. Conversely, combined trace element and Sr-Nd-Pb isotopic data for gabbronorites indicate a derivation from a source with composition similar to Indian-type mantle, but affected by fluid input in subduction environment. These geochemical features point out an evolution in a pre-Eocenic marginal basin setting, possibly in the proximity of a transform fault, for the lherzolites. Conversely, the harzburgites acquired their main geochemical and isotopic fingerprint in subduction zone setting.

CONFLITO RELIGIOSO, MARTÍRIO E EXALTAÇÃO VISIONÁRIA: O CASO DE ESTEVÃO EM ATOS 6,1-8,3

Nesta dissertação nos propomos a fazer uma leitura da narrativa de Atos dos Apóstolos 6,1-8,3, considerando-a nos moldes de uma antiga tradição de martírio. Os Helenistas entram em conflito com os Hebreus, Estevão entra em atrito com os judeus da diáspora que se reúnem nas sinagogas, e é levado perante o Sinédrio e executado. O motivo de sua execução é a crítica à Lei e ao Templo. Depois de ter uma experiência de êxtase visionário ele é violentamente assassinado. Lucas, todavia, descreve Estevão como herói vitorioso. A realidade de conflitos, oposição, perseguição e martírio não se constitui em derrota, mas em fortalecimento da fé. A morte de Estevão é interpretada dentro desta tradição. A compreensão do caso de Estevão e dos Helenistas é fundamental para entender a continuação do movimento dos seguidores de Jesus e o início do desenvolvimento da Cristologia após o evento pascal.(AU)

“Samira Doesn’t Live Here Any More” : Somali-Swedes’ mobility as transnational practice

This article explores transnational experiences within a group of Somali- Swedes, particularly how parents’ transnational practices are transferred to their children and how a transnational social space, built on close relationships on a global scale, is constructed. The readiness to relocate between countries and the implications for the children is illuminated. The onward migration to Egypt is highlighted as an example. According to research on Somalis in diaspora, they explain their propensity to move by claiming to be nomads, but this article indicates that it is also about their desire for better opportunities in combination with the cultural and economic marginalisation experienced in the West.

Ethnicities and values in a changing world

Recent debates about national identity, belonging and community cohesion can appear to suggest that ethnicity is a static entity and that ethnic difference is a source of conflict in itself. "Ethnicities and Values in a Changing World" presents an alternative account of ethnicity and calls into question models of community cohesion that present ethnicity as the source of antagonisms and differences that must be overcome. It suggests instead that ethnicity is itself multiple and changing and is unlikely to be a basis for articulating shared values. This volume brings together an international team of leading scholars in the field of ethnic studies in order to examine innovative articulations of ethnicity and challenge the contention that ethnicity is static or that it necessarily represents traditional values and cultures. Asserting that ethnicity is deployed in part as an expression of values and a model of ethical practice, this book examines displays of ethnicity as assertions of identity and statements about way of life, sense of entitlement and manner of connection to others. "Ethnicities and Values in a Changing World" draws together debates about the articulation of ethnic identity, the nature of our relation to each other and discussions of everyday ethics, thus engaging with discussions of racism, multiculturalism and community cohesion. As such, it will appeal not only to sociologists, but to anyone working in the fields of cultural studies, race and ethnicity, globalization, migration and anthropology. Table of Contents: Introduction: ethnicities, values and old-fashioned racism, Gargi Bhattacharyya; Teaching race and racism in the 21st century: thematic considerations, Howard Winant; Diaspora conversations: ethics, ethicality, work and life; Migrant women's networking: new articulations of transnational ethnicity, Ronit Lentin; 'The people do what the political class isn't able to do': antigypsyism, ethnicity denial and the politics of racism without racism, Robbie McVeigh; Violent urban protest - identities, ethics and Islamism, Max Farrar; Beliefs, boundaries and belonging: African Pentecostals in Ireland, Abel Ugba; On being a 'good' refugee, John Gabriel and Jenny Harding; Narrating lived experience in a binational community in Costa Rica, Carlos Sandoval Garcia; Conclusion: ethnicity and ethicality in an unequal world, Gargi Bhattacharyya; Index.

Ireland:from racism without ‘race’, to ‘racism without racists’

The Irish have been relentlessly racialized in their diaspora settings, yet little historical work engages with “race” to understand Irish history on the island of Ireland. This article provides an interpretation of two key periods of Irish history—the second half of the sixteenth century and the period since 1996—through the lens of racialization. I argue that Ireland's history is exceptional in its capacity to reveal key elements of the history of the development of race as an idea and a set of practices. The English colonization of Ireland was underpinned by a form of racism reliant on linking bodies to unchanging hierarchically stacked cultures, without reference to physical differences. For example, the putative unproductiveness of the Gaelic Irish not only placed them at a lower level of civilization than the industrious English but it also authorizes increasingly draconian ways of dealing with the Irish populace. The period since 1996, during which Ireland has become a country of immigration, illustrates how racism has undergone a transformation into the object of official state policies to eliminate it. Yet it flourishes as part of a globalized set of power relations that has brought immigrants to the developing Irish economy. In response to immigration the state simultaneously exerts neoliberal controls and reduces pathways to citizenship through residence while passing antiracism legislation. Today, the indigenous nomadic Travellers and asylum seekers are the ones that are seen as pathologically unproductive. Irish history thus demonstrates that race is not only about color but also very much about culture. It also illustrates notable elements of the West's journey from racism without race to racism without racists.

Invisible but not forgotten: The Afro-Argentine and Afro-Uruguayan experience from the sixteenth to the twentieth centuries

The problem to be examined in this thesis involves the supposedly overlooked history and contributions of Africans and their descendants in the River Plate countries of Argentina and Uruguay. Therefore, the primary purpose of the study is to narrate the social history of Afro-Argentines and Afro-Uruguayans from the sixteenth to the twentieth century. A secondary purpose, moreover, is to synthesize the academic literature on Blacks in the Rio de la Plata and their many cultural and other contributions to the current nation-states of Argentina and Uruguay. This thesis thereby challenges the regnant historiographical argument that African Argentines and African Uruguayans have been “forgotten” as historical actors by scholars both inside and outside the Rio de la Plata. By synthesizing the large body of historical and social science scholarship on Africans in the River Plate, as well as providing a thorough bibliography on the subject, this study attempts to proffer (to borrow the subtitle of Marvin Lewis' 1996 study of Afro-Argentine literature) “another dimension of the Black Diaspora” to the Americas. ^

The cultural politics of Jamaican dancehall music in South Florida

For Jamaicans throughout the Diaspora, dancehall music has emerged as their most potent cultural symbol demarcating their place of origin and continued sense of national belonging. Due to its unapologetic nature and tendency to tackle divisive issues such as those involving race, class, and sex, dancehall has been unfairly branded as wholly misogynistic and violent. This dissertation attempts to counter some of these assertions by exploring the cultural politics of dancehall music in South Florida's Jamaican community. Information for this study was obtained using participant observation, formal, and informal interviews. Participant observation was conducted over a 2 year period at several dancehall clubs and events throughout South Florida. A total of 24 formal and 30 informal interviews were conducted with listeners of the music and business owners who are directly and indirectly involved with the promotion, production, and distribution of dancehall in South Florida. ^ Results show that dancehall enacts cultural politics in three primary ways in South Florida. First, the music serves as one of several types of materials used in the construction of a "Jamaican identity." This is achieved through the lyrical content of the music where social, economic and political issues affecting the island are often discussed and debated. Second, dancehall operates as a form of cultural politics through its nurturing of nationalistic sensibilities. Evidence of this is apparent in the controversy involving dancehall's homophobic stance. Third, dancehall affords Jamaicans in South Florida the ability to transplant and perpetuate the uptown versus downtown divide. ^ Far from being wholly misogynistic and violent, therefore, dancehall is an important tool that can be used to address a wide variety of issues within the local Jamaican context and throughout the Jamaican diaspora. ^

Life pathways of Haitian-American young adults in South Florida

This research examines the life pathways of 1.5 and second generation Haitian immigrants in South Florida. The purpose of the research is to better understand how integration occurs for the children of Haitian immigrants as they transition from adolescence to adulthood. Building upon a prior study of second-generation immigrant adolescents between 1995 and 2000, a sub-set of the original participants was located to participate in this follow-up research. Qualitative interviews were conducted as well as in-depth ethnographic research, including participant observation. Survey instruments used with other second-generation populations were also administered, enabling comparisons with the Children of Immigrants Longitudinal Study (CILS). The results indicate that educational and occupational achievements were markedly below the participants’ original expectations as adolescents. Gender figures prominently in participants’ familial roles and relationships, with men and women distinctly incorporating both Haitian and American cultural practices within their households. Contrary to previous research, these results on the identification of participants suggest that these young adults claim attachment to both Haiti and to the United States. The unique longitudinal and ethnographic nature of this study contributes to the ongoing discussion of the integration of the children of immigrants by demonstrating significant variation from the prior integration trends observed with Haitian adolescents. The results cast doubt on existing theory on the children of immigrants for explaining the trajectory of Haitian-American integration patterns. Specifically, this research indicates that Haitians are not downwardly mobile and integrating as African Americans. They have higher education and economic standing than their parents and are continuing their education well into their thirties. The respondents have multiple identities in which they increasingly express identification with Haiti, but in some contexts are also developing racialized identifications with African Americans and others of the African diaspora.

Italianità on Tour: From the Mediterranean to Southeast Florida, 1896-1939

Italianità on Tour is a cultural history of Italian consciousness in Italy and Southeast Florida from 1896 to 1939. This dissertation examines literary works, folktales, folksongs, artworks, buildings and urban planning as imprints and cultural constructions of Italianità on both sides of the Atlantic, with a special emphasis on the transformations experienced on that journey. The real and/or imagined geo-cultural similarities between the Mediterranean and the Caribbean encouraged pioneers in Southeast Florida to conjure in their new setting an idea of Italianità , regardless of the presence of Italians in the area. Therefore, assessing Italianità, constitutes an important feature in understanding cultural constructions of identities in Miami and neighboring areas. This study, seeks to add Southeast Florida's Caribbean-Italian identity to the existing scholarship on several Italian diaspora representations, whether from a cultural ethnic perspective or from a sense of national belonging. More generally, it will show that there was no quintessential Italian national culture, but only representations of it that élites in Italy and South Florida manufactured, and on the other hand, immigrants imagined and performed upon arrival to America.