The Salado River fault: reactivation of an Early Jurassic fault in a transfer zone during Laramide deformation in southern Mexico

During Pangea breakup, several Jurassic extensional to transtensional basins were developed all around the world. The boundaries of these basins are major structures that accommodated continental extension during Jurassic time. Therefore, reconstructing the geometry of Jurassic basins is a key factor in identifying the major faults that produced continental attenuation during Pangea breakup. We reconstruct the tectono-sedimentary evolution of the Jurassic Tlaxiaco Basin in southern Mexico using sedimentologic, petrographic, and U-Pb geochronologic data. We show that the northern boundary of the Tlaxiaco Basin was an area of high relief composed of the Paleozoic Acatlán Complex, which was drained to the south by a set of alluvial fans. The WNW-trending Salado River–Axutla fault is exposed directly to the north of the northernmost fan exposures, and it is interpreted as the Jurassic structure that controlled the tectono-sedimentary evolution of the Tlaxiaco Basin at its northern boundary. The eastern boundary is represented by a topographic high composed of the Proterozoic Oaxacan Complex, which was exhumed along the NNW-trending Caltepec fault and was drained to the west by a major meandering river called the Tlaxiaco River. Data presented in this work suggest that continental extension during Pangea breakup was accommodated in Mexico not only by NNW-trending faults associated with the development of the Tamaulipas–Chiapas transform and the opening of the Gulf of Mexico, but also by WNW-trending structures. Our work offers a new perspective for future studies that aim to reconstruct the breakup evolution of western equatorial Pangea.

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Overcoming Challenges of International Migration Research: A Case Study Approach in Southern Mexico

MIGRATION LETTERS ◽

10.33182/ml.v13i1.268 ◽

2016 ◽

Vol 13 (1) ◽

pp. 131-143

Author(s):

Julie Boyles

Keyword(s):

International Migration ◽

Common Ground ◽

Data Gathering ◽

Ethnographic Case Study ◽

Case Study Approach ◽

Southern Mexico ◽

Mixed Methods Approach ◽

Study Approach ◽

Migration Research

An ethnographic case study approach to understanding women’s actions and reactions to husbands’ emigration—or potential emigration—offers a distinct set of challenges to a U.S.-based researcher. International migration research in a foreign context likely offers challenges in language, culture, lifestyle, as well as potential gender norm impediments. A mixed methods approach contributed to successfully overcoming barriers through an array of research methods, strategies, and tactics, as well as practicing flexibility in data gathering methods. Even this researcher’s influence on the research was minimized and alleviated, to a degree, through ascertaining common ground with many of the women. Research with the women of San Juan Guelavía, Oaxaca, Mexico offered numerous and constant challenges, each overcome with ensuing rewards.

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The value, costs, and meaning of transnational migration in rural Oaxaca, Mexico

MIGRATION LETTERS ◽

10.33182/ml.v6i1.83 ◽

2006 ◽

Vol 3 (1) ◽

pp. 15-25 ◽

Cited By ~ 1

Author(s):

Jeffrey H. Cohen ◽

Bernardo Rios ◽

Lise Byars

Keyword(s):

Social Networks ◽

Sense Of Belonging ◽

Southern California ◽

Transnational Migration ◽

Urban Centers ◽

Cultural Economic ◽

Southern Mexico ◽

Shared Identity ◽

The Social

Rural Oaxacan migrants are defined as quintessential transnational movers, people who access rich social networks as they move between rural hometowns in southern Mexico and the urban centers of southern California. The social and cultural ties that characterize Oaxacan movers are critical to successful migrations, lead to jobs and create a sense of belonging and shared identity. Nevertheless, migration has socio-cultural, economic and psychological costs. To move the discussion away from a framework that emphasizes the positive transnational qualities of movement we focus on the costs of migration for Oaxacans from the state’s central valleys and Sierra regions.

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