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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.
21

Geologic setting and silver mineralization in the Planchas de Plata area, northern Sonora, Mexico

Segerstrom, Lawrence, 1954- January 1986 (has links)
No description available.
22

AN ANALYSIS OF AGRICULTURAL PRODUCTION IN MEXICO, 1969-1979, AND COMPARISONS WITH THE UNITED STATES.

Salmon-Castelo, Roberto Fernando. January 1982 (has links)
No description available.
23

ENVIRONMENT AND SEASON IN A TROPICAL DECIDUOUS FOREST IN NORTHWESTERN MEXICO

Krizman, Richard Donald, 1931- January 1972 (has links)
No description available.
24

Use of geostatistics in developing drilling programs at the Cananea copper mine

Cervantes-Montoya, Jesús Alberto January 1981 (has links)
No description available.
25

Regional geology in the Opodepe mining area, Sonora, Mexico

Ramírez Muñoz, José January 1979 (has links)
No description available.
26

Geology of the Santa Rosalia mine area, district of Arizpe, Sonora, Mexico

Moore, David Lafayette, 1916- January 1948 (has links)
No description available.
27

Geology and depositional environment of the Oposura massive sulfide deposit, Sonora, Mexico

Marrs, Christopher Dean January 1979 (has links)
No description available.
28

Stratigraphy, depositional environments, and origin of the Cabullona Basin, northeastern Sonora, Mexico.

González-León, Carlos Manuel. January 1994 (has links)
The Cabullona Basin of northeastern Sonora is a structural depocenter that was formed during Late Cretaceous time. The 2.5 km-thick sedimentary fill of this basin, the Cabullona Group, is composed in ascending order of the Corral de Enmedio formation, Camas Sandstone, Packard Shale, Lomas Coloradas formation, and, laterally equivalent to the last two units, El Cemento conglomerate. Abundant vertebrate and invertebrate as well as pollen identifications from these units indicate the Cabullona Group is of middle Santonian to Maastrichtian age. The Corral de Enmedio formation represents shallow lacustrine deposits. Lithofacies of the Camas and Lomas Coloradas formations indicate they were deposited by braided- and meandering-fluvial systems, whereas the eight members of the Packard Shale represent complex fluvio-deltaic-and-lacustrine systems. The El Cemento conglomerate is a thick clastic wedge of coarse-grained alluvial deposits that was deposited adjacent to the structural margin of the basin. Clast composition and paleocurrent directions of the El Cemento conglomerate indicate it was derived from strata of the nearby uplift of the Sierra Anibacachi-Cerro Cabullona. The low-angle, southwest directed Cabullona thrust fault that separates the uplift from the basin formed the structural margin of the basin. The tectono-sedimentary history of the Cabullona Group, its age and regional tectonic setting support the idea that this basin was formed because of typical Laramide-style deformation and indicates that the Rocky Mountain foreland province of Laramide deformation extended southward to northeastern Sonora.
29

MATING SYSTEMS IN TROPICAL MARINE FISHES: THEORY AND CASE STUDIES OF SIMULTANEOUS HERMAPHRODITISM AND PATERNAL CARE (SERRANUS, LABRISOMIDAE, GULF CALIFORNIA).

PETERSEN, CHRISTOPHER WILLIAM. January 1985 (has links)
This study investigates two aspects of tropical reef fish mating systems: the prevalence of paternal care in those species that exhibit some form of parental care, and the evolutionary stability of simultaneous hermaphroditism. Studies of three species of tropical reef fishes from the Gulf of California were used to investigate these two different types of mating systems. Two species of demersal egg guarders with paternal care, Malacoctenus hubbsi and Abudefduf troschelii, were studied to determine the importance of a male's mating status (the number of eggs in his territory) in regard to female choice of mates. In both species, females did not base their choice of mates on the number of eggs in the male's territory, males increased their level of parental care with increasing egg number, and egg survivorship where estimated was independent of brood size. These results corroborate, and offer the first experimental field verification of a crucial assumption of a minimal-care hypothesis proposed a decade ago by Williams (1975). Male reproductive success was studied in greater detail in one species, M. hubbsi. Territory parameters, rather than male size, were the major determinants of male reproductive success. This independence relative to male size was attributed to the unpredictability of good future territories. In Serranus fasciatus all individuals begin reproduction as simultaneous hermaphrodites, but lose female function at large sizes to become males. Males obtain disproportionate reproductive success by maintaining harems of hermaphrodites and defending them from adjacent males. These harems are similar to those found in some sequentially hermaphroditic species. Hermaphrodites obtain most of their reproductive success through female function by spawning with a male, but also engage in an alternative male strategy--streaking on pair spawns--to obtain some male reproductive success. This small amount of male reproductive success by hermaphrodites appears to stabilize simultaneous hermaphroditism with most resources allocated to female function. Facultative alternative male mating strategies in hermaphroditic individuals joins spawning reciprocation as the only known behavioral strategies that provide evolutionary stability for simultaneous hermaphroditic individuals in populations of tropical reef fishes.
30

Coastal landforms and vegetation associations of the straits of Infiernillo Region, Sonora, Mexico: a poleward habitat for mangroves

Sherwin, Robert Winslow, 1945- January 1971 (has links)
No description available.

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