Thesis (S.S.P.)--Smith College, Northampton, Mass., 2008. / V. 1 is a collection of poems ; v. 2 is a collection of essays. Typescript. Includes bibliographical references (v. 2., p. 77-78)

A variety of world-class mineral deposits occur in Mesozoic and Tertiary rocks of the Guerrero terrane. New Pb isotope analyses of various crustal units and ores from distinct subterranes of the Guerrero terrane are presented to trace metal sources in these deposits and infer source reservoirs. New Sr and Nd isotope results are provided to gain insight into the provenance of the crustal rocks from the Guerrero terrane. Triassic schist samples from the Arteaga Complex and Triassic-Jurassic phyllite and slate samples from the Tejupilco metamorphic suite contain radiogenic Pb (206Pb/204Pb = 18.701-19.256) relative to bulk earth models. Cretaceous sedimentary rocks of the Zihuatanejo Sequence are more radiogenic (206Pb/204Pb = 18.763-19.437) than samples from the Huetamo Sequence (206Pb/204Pb = 18.630-18.998). Tertiary intrusive rocks from La Verde, Inguaran, La Esmeralda, and El Malacate plot to the right of the average Pb crust evolution curve of Stacey and Kramers (206Pb/204Pb = 18.705-19.033). Ores from the La Verde and La Esmeralda porphyry copper deposits yield isotopic ratios (206Pb/204Pb = 18.678-18.723) that are generally less radiogenic than the host igneous rocks, but plot within the field defined by the sedimentary rocks from the Huetamo Sequence. Tertiary intrusive rocks from the Zimapan and La Negra districts in the Sierra Madre terrane plot above and to the right of the Stacey-Kramers reference line (206Pb/204Pb = 18.804-18.972). Lead isotope ratios of ore minerals from the Zimapan and La Negra skarn mines (206Pb/204Pb = 18.775-18.975) resemble those of the associated igneous rocks, implying a magmatic Pb input in the skarn deposits. New Sr and Nd isotope data on metamorphic rocks (87Sr/86Sr = 0.707757-0.726494 and 143Nd/144Nd = 0.512109-0.512653) suggest that the basement of the Guerrero terrane originated from sources that had been derived from an old cratonic area. The narrow ranges and generally low 87Sr/86Sr ratios (0.704860-0.705755) and 143Nd/144Nd values (0.512765-0.512772) above that of bulk earth for igneous rocks from Inguaran, El Malacate, and La Esmeralda suggest a relatively low degree of crustal contamination. However, the isotopic values for the La Verde site (87Sr/86Sr = 0.708784 and 143Nd/144Nd = 0.512640) may indicate the involvement of a more evolved crustal component.

No description available.

La caractérisation des distributions spatio-temporelles des déformations transitoires le long de failles actives constitue actuellement l’un des axes privilégiés de recherches visant la compréhension des processus contrôlant le cycle sismique. Dans ce contexte, nous nous intéressons à deux sites d’études aux caractéristiques comportementales distinctes: la lacune sismique de Guerrero, siège de 4 séismes lents depuis 1997 (zone de subduction, d’une longueur de 100 km à l’ouest d’Acapulco au Mexique, dernière rupture en 1911, temps de récurrence ~4 ans) et le segment de Parkfield (segment de 20-30 km le long de la faille de San Andreas, Californie, 7 ruptures successives -Mw6- depuis 1857, temps de récurrence de ~22 ans). Dans le cas du Mexique, nous portons notre attention sur le séisme lent de 2009-2010 survenu au niveau de la lacune sismique et, dans le cas du segment de Parkfield, nous décrivons la déformation post-sismique suite au séisme du 28 septembre 2004, dernière rupture en date de ce segment, sur la période 2005-2010. Nous utilisons l’interférométrie radar différentiel satellitaire (DINSAR), complété de données GPS, pour estimer les faibles déformations (centimétriques) générées en surface par ces types de déformations. À l’issue de ce travail, dans le cas de la lacune sismique de Guerrero, nos mesures semblent montrer que le séisme lent de 2009-2010 affecte la partie sismogène de la lacune tout en affectant une portion de la subduction qui dépasse les limites géographiques de celle-ci. Dans le cas de Parkfield, nous parvenons à mettre en avant une prolongation temporelle jusqu’en 2010 du glissement post-sismique en plus d’une extension spatiale de ce glissement qui dépasse les limites de la rupture de 2004. Ces nouveaux éléments permettent de discuter plus en avant l’impact de ces déformations transitoires sur le comportement de ces systèmes de failles situés tout deux, sur des sites d’intérêts scientifiques majeurs. / Characterizing the spacio-temporal evolution of transient deformations along active faults is, by now, one of the most promising ways to better understand the mechanisms that drive the seismic cycle. In this context, we focused our attention on two areas that exhibit different characteristic behaviour types: the Guerrero seismic gap, a location of 4 consecutive slow slip events since 1997 (subduction zone, 100 km long westward from Acapulco, Mexico, last ruptured in 1911, repeating time ~4 years) and the Parkfield segment (20-30 km long segment, San Andreas fault, California, 7 successive breaks -Mw6- since 1857, repeating time ~22 years). In the case of Mexico, we particularly focused our attention on the 2009-2010 slow slip event that occurred at the gap location. In the case of Parkfield, we described the post-seismic deformation related to the 28th September 2004 Mw6 event (last recorded break) from 2005 to 2010. We used space-based differential radar interferometry (DINSAR) in addition to GPS data, to assess surface displacements at centimeter scale that are in relation with those two phenomena. As an outcome of the work, in the Guerrero seismic gap case, our measurements indicate that the 2009-2010 slow slip event has affected the seismogenic part of the gap and extents outside the spatial limits of it. In the case of Parkfield, our measurements indicate that the Parkfield segment has a post-seismic behaviour that lasts until 2010 at least and spatially extends outside the edge the 2004 coseismic trace along the fault line. These elements allow us to discuss the implication of such transient deformations in the two particular cases of the Guerrero seismic gap and the Parkfield segment, both of first scientific interest.

Thesis--University of Michigan. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

The tropes of the diablo, the macho, the indio and the bronco have served as a means by which the state of Guerrero, Mexico, has been discursively defined, both externally and internally. I employ a critical reading of these tropes in an analysis of several commemorative performances that characterize the historical imaginary of northern Guerrero. The heart of the study is a description and analysis of the Diablos of Telolopan, a tradition which is celebrated as part of the Fiestas Patrias, and commemorates local participation in Mexico’s War for Independence, 1810-1821. I compare this tradition with other regional commemorations, including alternative fiestas patrias, the Abrazo of Acatempan, and the Festival of Cuauhtémoc, arguing that commemorative performance forms part of a poetics of history which resists the imposition of national hegemonic historiography. I complement the study of local history-making with an analysis of the way in which space and memory come together in the practices that surround death in Teloloapan. / text

Thesis--University of Michigan. / Includes bibliographical references. Also issued in print.

The investigation of the relationships between migration processes and the reconstructions of social identities and of social relations within local, national and international contexts illustrates how social change in an Oaxacan community in Mexico is a complex, multi-faceted process. This study examines how migration processes and social change shape and are shaped by people and practices in specific historical moments interacting dialectically with broader social, economic and political structures. By paying greater attention to the quotidian and to the choices that people make as they go about their daily lives, the heterogeneity and multiplicity of community members' subjectivities and experiences are highlighted. Gender, ethnicity, race, age, class, sexuality, and religion are examined as crucial variables in processes of social differentiation and in the social reproduction of gender/racial/class hierarchies in which women and men are situated. The research applies the concept of hegemony to demonstrate that power is not separate from meaning; the social construction of meanings plays an important role in the creation of consent, collaboration or resistance. Community members have internalized their own domination through hegemonic processes, reproducing the dominant social order, yet they frequently challenge their own particular social locations within this social order. Migration processes and the globalization of communication and consumption in advanced capitalism have played key roles in these processes. New experiences and information technologies have led to a redefining and re-presenting of meanings and practices which have had negative and positive impacts on individuals, on families and on the community.

No description available.

Remittances form an important source of revenue for many farm households and rural communities. In spite of their significance, how remittances are expended is not well studied. Neoclassical economic theory indicates that the welfare of recipients unequivocally improves as the household budget line increases. Which new combination of goods, such as production and leisure, is selected on the budget line depends on household and community preferences. The literature suggests many factors influence preferences. The original resource endowment defines production possibilities. Regional economic conditions determine agricultural profitability and alternative investment opportunities. The volume and timing of remittances influence a farmer's willingness to accept risk. Socio-economic survey data from 54 households in the village of El Rosario Micaltepec, Puebla in the Mixteca Baja region illustrate the conditions under which certain households may choose to invest remittances in agricultural production. Data on the activities of the migrant village associations of two villages are used to evaluate the circumstances that favor community investment of migrant-donated funds over their conspicuous consumption.