Chacoan great houses have been described as providing "ritual" or "integrative" venues and as "monumental" in scale and in the amount of labor required for their construction. This study takes the approach that part of the function of community, monumental, or ritual structures is to transmit meaning and that an examination of visibility connections between these structures and small habitation sites in the surrounding community may provide information about the role of these messages in daily practice. Survey data from the Chacoan community at Kin Bineola, New Mexico is analyzed in a GIS environment using a model of visibility and distance developed for this project. The results show that, contrary to expectations, the great house is much less visible than a less monumental "Chacoan structure." Shrines, small structures interpreted as having a ritual function, are by far the most visible, suggesting a more complex relationship between monumentality and visibility.

An important fraction of the reservoirs in the Outer Continental Shelf of the Gulf of Mexico is comprised of thin-bedded deposits from channel-levee systems. These reservoirs are particularly difficult to describe. Not only is their architecture complex but the quality of the reservoir is determined by connection and length of beds below the resolution of usual reflection data. Improved characterization is needed to improve development and production of these reservoirs. This study presents an integrated approach to build a geologically consistent reservoir model, based on the 8 sand reservoir in Northern Green Canyon block 18. The underlying idea of the construction of this model is that reservoir quality is influenced more by the internal architecture than by the statistical values of petrophysical parameters. Seismic interpretation and attribute extraction provided the reservoir geometry and stratigraphy. The structural framework and the limits of the reservoir have been determined, showing the preeminent role of salt and faults in the constitution of this reservoir. Seismic attributes are calibrated to extract areal information on reservoir architecture. Gross thickness and net thickness maps have been estimated using geostatistical methods. Lateral variations in the quality of the 8 sand and the definition zones with different average properties were inferred from geostatistical results. Lithofacies characterization from core showed that 3 facies could be used to describe the internal variability. The fine-scale heterogeneity is described in each zone from vertical facies distribution determined from wells. A truncated Gaussian sequential simulation was performed to reflect both the regional trend and the internal variability on a 150*150*1 ft grid. The major contribution of this work is to show the efficiency of this approach to describe complex reservoirs where the impact of internal variability is a major control of flow efficiency. This is especially valuable when the well information is scarce or not uniformly distributed. This model will be used for flow simulation and sensitivity analysis to improve the field description.

Thesis (M.A.) -- Brigham Young University. Dept. of History, 1949.

Thesis (M.A.) -- Brigham Young University. Dept. of History, 1949. / Electronic thesis. Also available in print ed.

Certain sites within Death Valley National Park contain ample ichnofossils, specifically vertebrate animal tracks, dating back to the Pliocene. Since the majority of these track locations are closed to the general public, their scientific significance and educational value toward improving the geoliteracy of the general public remain unexplored. Based on the impressive amount of ichnofossils present at the park, this research investigates how to improve general public geoliteracy through these tracks, using basic principles and supporting concepts of the National Science Foundation’s Earth Science Literacy Initiative, while respecting the security measures of the park and adhering to National Park Service interpretation guidelines.

A severe wildfire burned 454 hectares of a second-growth Douglas-fir forest in 1977 on a north-facing slope in Pattee Canyon, near Missoula, Montana. The slope was aerially seeded with a grass mixture, from which Dactylis glomerata established best. Community structure, conifer regeneration, and the impact of the seeded grass on the plant community were evaluated with two data sets. One set tracked postfire vegetation development from 1979 to 1987 on permanent transects established on upland sites in areas of varying fire severity. The second data set was collected in 1989 on upland sites nearest to the bum edge where conifer regeneration was expected to be greatest. Most stands converged to a similar ordination space by 1987, showing that several key species which established in the initial postfire year determined community structure. These species were largely on-site survivors (including Calamagrostis rubescens, Physocarpus malvaceus, and Spiraea betulifolia) and the seeded grass, D. glomerata. The spread of this species by 1987 to stands that apparently escaped seeding in 1977 suggested that this species may persist at this site. Patterns of species abundance and distribution in 1989 were primarily controlled by factors summarized by a topographic-moisture index and by pre-burn disturbance history. Three general site types were described by an ordination. Areas that appeared as open woodlands in 1937 occurred on ridges and had more xerophytic vegetation in 1989, including native grasses. Conifer regeneration in this region was limited primarily to Pseudotsuga menziesii (Douglas-fir). Areas that appeared as an even, young forest in 1937 were on open slopes and were associated with Pinus contorta (lodgepole pine), Larix occidentalis (western larch), Vaccinum globulare, and Amelanchier alnifolia. Areas that appeared as an older, uneven-aged forest in 1937 were on open slopes near the upper burn edge and were characterized by Douglas-fir and Spiraea betulifolia in 1989. D. glomerata was more successful on the drier ridges and was negatively associated with Calamagrostis rubescens. Competition with C. rubescens, rather than differences in environmental tolerances, most likely restricted D. glomerata to the more xeric sites. An adverse effect of D. glomerata on conifer regeneration was most likely for western larch on xeric sites. Site factors and historical factors were most important in determining patterns of conifer regeneration. Regeneration was moderate on mesic slopes and sparse on xeric ridges. The extreme density of lodgepole pine regeneration (13,000 stems/hectare) in one mesic area reflected the importance of serotiny for post-fire regeneration of this species. Douglas-fir regeneration ranged from 370 stems/ha in a mesic area where no mature survivors were noted to 4045 stems/ha on a mesic slope near survivors. On mesic slopes near survivors, western larch regeneration was 857 stems/ha and was minimal elsewhere. A regression model confirmed the importance of site factors, site history, and availability of seed source for Douglas-fir and lodgepole pine. The model for western larch was only able to explain 14% of regeneration pattern, suggesting that microsite variation as well as other variables would be needed to predict regeneration for this species. / Graduation date: 1992

No description available.

No description available.

The density, diversity, and nest-site selection of riparian breeding birds were studied from 1982 to 1985 in mesquite (Prosopis glandulosa) and tamarisk (Tamarix chinensis) communites along the Colorado River in northern Arizona. Avian density in tamarisk communities was significantly greater (P=0.052 and 0.024 in 1984 and 1985, respectively) than avian density in native mesquite communities with similar vegetative cover and height attributes. Avian diversity was similar in both communities. Breeding bird densities in tamarisk were higher than those reported from other geographic areas. Vegetation structure and shrub species composition were measured at nest sites of eleven species of riparian birds in a tamarisk community to examine avian habitat relationships. Riparian birds exhibited differences in their choice of nesting habitat. Discriminant analysis indicated that Bell's Vireo (Vireo bellii), Yellow Warbler (Dendroica petechia) and Yellow-breasted Chat (Icteria virens) were relative generalists in nest site selection, while Common Yellowthroat (Geothlypis trichas) and Northern Oriole (Icterus galbula) were relative habitat specialists. Bell's Vireo and American Coot (Fulica americana) nested in habitats that were the most different. Willow Flycatcher (Empidonax traillii) and Yellow Warbler nested in habitats that were the most similar. Willow Flycatcher and Yellow Warbler consistently used habitat most similar to that used by all other species. Nest placement preferences of six riparian passerines were examined in the tamarisk community to test the null hypothesis that nest placement in any given species of shrub was random. Ninety-five of 105 nests sampled were located in tamarisk. Five of the six species of passerines exhibited a significant preference for tamarisk for nest placement. A highly significant preference for tamarisk was shown by the four species with the smallest median frequency of tamarisk in their nesting habitat. The usefulness of tamarisk for nest placement was higher than that reported from other areas.

The major goal is to reveal the need to understand the dynamics and impacts of landscape change from a current temporal perspective. This is performed here through the study of various settings in the landscape along Highways 180 and 64/180 in Arizona, being proposed for State Scenic Road designation. Selected landscape segments is the subject and the highways are a flexible platform from which to observe and assess these landscapes. Once sources, kinds of, and magnitude of possible or potential landscape changes and impacts are identified, this study proceeds to prescribe landscape planning strategies for their scenic and open space protection and enhancement. Potential landscape change and its impact should be predicted in order to plan and manage for the protection and enhancement of desired landscape values into the future. It can input people's perceptions to appreciate landscape values from varied perspectives such as: aesthetic, ecological, cultural, and socioeconomic.