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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

Geologic structure of the western continental margin of south central Baja California based on seismic and potential field data

Coperude, Shane Patrick 14 November 1977 (has links)
Marine geophysical data from the continental margin of Baja California and the Gulf of California, and geological and geophysical data from the Baja California Peninsula and mainland Mexico, outline the major geologic and tectonic features of the Baja California Peninsula and the surrounding areas from 24.5° N. Lat. to 27.5° N. Lat. A crustal and subcrustal cross section consistent with observed gravity and magnetic anomalies, and constrained by seismic refraction stations and the mapped surface geology shows major variations of density and magnetization in these areas. A geologic interpretation of the cross section indicates the rocks of the Pacific continental margin are composed of unconsolidated and semiconsolidated sediments. Tertiary sedimentary rock, metamorphic rock of Franciscan type, and continental crystalline rock probably corresponding to the Peninsular Range batholith. The depth to mantle under the Baja California Peninsula is postulated to be 20 km. In the Gulf of California a section of low-density mantle beginning at a depth of 11 km is necessary to fit the observed gravity values and accounts for the low seismic velocities associated with the mantle in the Gulf. The correlation between the observed magnetic anomalies on the Pacific continental margin of the Baja California Peninsula and the theoretical magnetic anomalies expected from a spreading center shows that the youngest identifiable remanent anomaly on the Pacific side of south central Baja California is anomaly 3' formed at 6 my B.P. The remanent magnetic anomalies extend 50 km landward from the western edge of the continental slope. / Graduation date: 1978
2

Recent changes in the cultural landscape of the cape region of Baja California

Hoffman, Peter Richard, 1947- January 1974 (has links)
No description available.
3

The Mexicali experimental project : an analysis of its changes

Ruesjas, Ana Laura. January 1997 (has links)
During 1975 the Architect Christopher Alexander designed and built an experimental project for low income people in the city of Mexicali, Mexico. The aim of the project was to create a beautiful place, not just of architectural beauty but in its essential spirit, in its quality of life. A number of patterns, taken from the book A Pattern Language, were used to design the environment. The residents played an important role in the design of their place: this, according to the author, would guarantee that the place would directly respond to their physical and spiritual needs. / Today, 20 years later, the project has undergone a lot of changes. People have continued the building process by themselves. Additions, modifications and changes in the use of spaces have blended the project with the neighborhood. This research attempts to describe the project's changes, to explain the motivating factors in its changes, and to evaluate the designer's original goals. It reveals the discrepancy between the architect's intentions and the actual needs of the residents. In this respect, the transformations observed show the incorporation of a culturally-based production process, suggesting the existence of an already inherent building practice that was neglected in the Mexicali approach.
4

The Mexicali experimental project : an analysis of its changes

Ruesjas, Ana Laura. January 1997 (has links)
No description available.
5

Geophysical exploration of the El Arco-Calmalli mining district, Baja California, Mexico

Farías García, Ramón, 1941- January 1978 (has links)
No description available.
6

Community-based sea turtle conservation in Baja, Mexico : integrating science and culture

Bird, Kristin E. 12 April 2002 (has links)
This thesis discusses both theoretical and practical considerations inherent in conducting community-based research within a case study of sea turtle conservation in Baja California, Mexico. A brief background, including the general ecology, status and distribution of sea turtles of the Baja peninsula is presented, with an overview of the current and historic use and management of sea turtles. Several sets of theories provide the context within which the case example is analyzed. A discussion of how concepts of "science" and "knowledge" are shaped and how these perceptions impact choices made in natural resource management and planning is presented. This includes a brief discussion of conservation ethics and conservation rationale, as well as a review of the debates surrounding indigenous knowledge and its application in conservation. A review of community-based efforts in sea turtle conservation is also presented. The data and analysis offered in this thesis is the result of two field seasons working as a member of an interdisciplinary sea turtle conservation team: conducting biological studies, surveys, informal and semi-structured interviews and participant observation. The major goal of this research project was to evaluate a people-oriented approach to conservation. The objectives of the Baja sea turtle conservation project included: the involvement of fishing communities in the development of conservation projects, the involvement of local students and fishermen in the collection of data and the public sharing of research results on a regular basis. Results of this case study suggest that through dependence on the host community for food, equipment, labor and guidance a special connection was established, fostering trust and building the partnerships necessary for long-term conservation success. For this reason, fishermen and other members of the local host communities were more willing to cooperate with outsiders and share their intimate knowledge of their environment - including information on the daily movements and distribution of sea turtles. It is crucial that the fishermen feel empowered before they choose to participate in the sea turtle conservation efforts. They must be viewed, and view themselves, as an integral part of the conservation team contributing valuable knowledge and ideas, not just acting as boat drivers and guides for outside researchers within the host community. Community meetings served as an outlet to voice concerns and share information. The active involvement and participation of local communities is a highly effective tool in the sea turtle conservation efforts in the region. / Graduation date: 2002
7

The relationship of two seagrasses: Zostera marina and Ruppia maritima to the black brant, Branta bernicla nigricans, San Ignacio Lagoon, Baja California, Mexico

Ward, David Hume January 1983 (has links)
ix, 60 leaves : maps ; 28 cm Notes Typescript Thesis (M.S.)--University of Oregon, 1983 Includes vita and abstract Bibliography: leaves 56-60 Another copy on microfilm is located in Archives
8

Effects of local environmental factors and spatial habitat characteristics on the density of a marine gastropod, Megastraea undosa (Wood 1828)

Abshire, Courtney Burke 20 December 2010 (has links)
The ability to identify and define factors which affect the abundance of marine species has been a primary goal of many ecologists. The need to accurately quantify the relationship between an organism and its environment is of critical importance in cases where that organism is the object of commercial harvest and tied to the economic well being of communities. This is especially evident for communities located along the Pacific coast of the Baja California peninsula where local fishing cooperative and their associated communities are dependent on the continuing successful harvest of a limited number of marine species, one of these being the marine gastropod Megastraea undosa (Wood, 1828). I conducted a multi-scale observational study investigating the effects of scale and selected local environmental and regional habitat characteristics of subtidal rocky reefs on the density of M. undosa. The study showed that M. undosa density varied significantly at two scales: quadrat (m2) and reef (100s m2). At the reef level, area and percent total cover were found to have a significant positive relationship with M. undosa density. No measured variable showed a significant association to M. undosa density at the quadrat level. Results suggest that both local and regional factors combine to affect M. undosa density and that their impacts on M. undosa density warrants further study. / text
9

EVOLUTIONARY SIGNIFICANCE OF ADAPTATIONS IN HETEROMYID RODENTS IN BAJA CALIFORNIA, MEXICO

Roth, Edward Lee, 1944- January 1976 (has links)
No description available.
10

The blister beetles of Baja California and adjacent islands (Coleoptera: Meloidae)

Radford, Keith W. January 1960 (has links)
No description available.

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