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Paleoecological studies from fecal pellets: Stanton's Cave, Grand Canyon, ArizonaIberall, Eleanora Roberta, 1942- January 1972 (has links)
No description available.
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Piapaxa 'Uipi (Big River Canyon)Stoffle, Richard W., Halmo, David B., Evans, Michael J., Austin, Diane E. 06 1900 (has links)
The traditional lands of the Southern Paiute people are bounded by more than 600 miles of Piapaxa (Colorado River) from the Kaiparowits Plateau in the north to Blythe, California in the south. According to traditional beliefs, Southern Paiute people were created in this traditional land and, through this creation, the Creator gave Paiute people a special supernatural responsibility to protect and manage this land including its water and natural resources. Puaxantu Tuvip (sacred land) is the term that refers to traditional ethnic territory. Within these lands no place was more special than Piapaxa 'uipi (Big River Canyon) where the Colorado River cuts through the Grand Canyon.
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Itus, Auv, Te'ek (Past, Present, Future)Stoffle, Richard W., Austin, Diane E., Fulfrost, Brian K., Phillips III, Arthur M., Drye, Tricia F. 09 1900 (has links)
This report concludes the first four years (1992 -1995) of Southern Paiute involvement in the Glen Canyon Environmental Studies (GCES), a program initiated by the Bureau of Reclamation (BOR) in 1982. Southern Paiutes have conducted ethnographic research and participated in the Congressionally mandated Environmental Impact Study (EIS) of Glen Canyon
Dam water release policies on natural and human-made resources found in the Colorado River Corridor. These ethnographic studies have taken place in what is called the Colorado River Corridor which extends 255 miles down stream from Glen Canyon Dam to the end of the free flowing river at Separation Canyon within the Grand Canyon National Park. They have concentrated on investigating the impacts of the Dam's water releases to Southern Paiute cultural resources. Since the Final EIS was published in March 1995, emphasis has been placed on what is called the Adaptive Management Program of the GCES and attention has shifted to monitoring the water release impacts.
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Shelf-to-canyon sedimentation on the South Westland Continental Margin, Westland, New Zealand.Radford, Josh January 2012 (has links)
The South Westland Continental Margin (SWCM) is incised by two major active canyon channels, the Hokitika and Cook canyons, which export large volumes of terrigenous sediment from the active New Zealand landmass to the deep ocean basins. This thesis examines modern sediment textures and compositions of shelf and canyon heads, to interpret depositional and transport processes in shelf-canyon interactions and the dispersal and provenance of SWCM surface sediments. This is the first detailed study of modern sediments south of the Whataroa River which focuses on both shelf and canyon head sediments. Submarine canyons that incise active continental shelves are major conduits for sediment transfer. The frequency and magnitude of this transfer has important implications for ocean nutrient cycling (i.e. organic carbon), the stratigraphy and morphology of continental shelves, and the development of economic mineral deposits. Grain size analysis, petrology, geochemistry, detrital magnetite analysis (microprobe), swath bathymetry, and wave hindcast data are used to interpret the spatial distribution, dispersal, and provenance of surface grab samples, canyon cores, and beach and river samples on the SWCM.
Four main surficial facies are defined from textural and compositional results, primarily reflecting the supply and storm dominated nature of the SWCM. Facies 1 is comprised of inner shelf very fine to medium sand sized quartz, metamorphic lithics, and feldspar. This facies occurs above the mean Hsig wave base (48 m) where silts, clays, and sand sized micas are bypassed further offshore. Facies 2 is a transitional sand to mud facies between 40 -70 m depth where increasing clay, silt, and mica reflect a decrease in the frequency and magnitude of wave orbital remobilisation. Facies 3 is a mud dominated (80-90%), clay rich (7-9%) facies with the highest mica and Al₂O₃ content of all the SWCM facies. The shelves south of the Hokitika canyon are blanketed beyond the inner shelf in facies 3 towards the shelf break. Facies 4 is restricted to the canyon head north rims and is characterised by mixed relict and modern terrigenous sediments and glaucony. Net transport on the SWCM shelf is to the north, particularly during south-westerly storms where wind drift and storm swells may stir and transport the deeper Facies 2 and 3 sediments. The SWCM has an energetic wave climate and numerous high yield mountainous rivers. As a result the shelf has an extensive coverage of silts and clays with sediment transport most likely dominated by nepheloid layers and fluid mud flows during wet storms. North of the Hokitika canyon, shelf width increases as fluvial supply falls, resulting in a more storm dominated shelf as the prevailing hydraulic conditions prevent modern silts and clays from blanketing the outer shelf. Narrower shelf widths and higher fluvial supply between the Hokitika canyon and the Haast region results in more fluvial dominated shelves.
Contrasting canyon rim textures and compositions reflect the major influence the Hokitika and Cook canyon heads impose on the SWCM by intercepting modern net northward shelf transport paths. This interception creates a leeward sediment deficit on the canyon north rims where low sedimentation rates prevail and relict sediments are partially exposed. The south and east rims of both canyons are characterised by modern fine grained terrigenous textures and compositions similar to the SWCM middle to outer shelf facies 3. The build-up and storage of these unconsolidated sediments at the south and east rims provides favourable environments for sediment gravity flows that feed into the canyon systems. Wave orbitals can resuspend fine sands up to 50 m below the canyon rims during large storms. This resuspension will be a main driver of canyon head sedimentation in the form of fluid mud flows. Gully networks along the south and east rims of the Hokitika and Cook canyons indicate active submarine erosion, unconfined fluid flow, and sediment gravity flows operate here.
ii
In contrast, the north canyon rims are characterised by gravels and coarse sands out of equilibrium with the prevailing modern hydraulic regime. Relict gravels are particularly prevalent on the Hokitika canyon north rim between 90 – 150 m depth. A lack of active gully networks and the presence of relict terraces and cuspate channels provide further evidence for a relict origin of HCH north rim sediments and little influx of modern fine sediments. North rim sediments on the Hokitika canyon between 90 – 125 m have features characteristic of relict beach and littoral environments. These features include pebble and coarse sand sized siliciclastics, high heavy mineral percentages (i.e. garnet), high Zr and Y levels, elevated SiO₂/Al₂O₃ ratios, and relict shell fragments. Mature glaucony is common on the north rims of both canyons, especially between 180 -200 m depth providing further evidence for extended periods of little to no modern sediment deposition in the canyon lee. Glaucony grains have experienced limited transport and are probably parautochthonous.
The bulk composition of SWCM shelf, canyon, river, and beach sediments is controlled mainly by the hydrodynamic sorting of Alpine Schist derived material. Regional changes in catchment geology are identified in modern SWCM shelf sediments. Ultramafic signals (i.e. enriched trace element patterns and Cr/V and Ni/Y ratios) from the Pounamu Ultramafics and Dun Mountain Ultramafics were identified on the North and Cascade shelves respectively. The contribution of other lithologies to the bulk composition of SWCM sediments is localised due to rapid dilution with Alpine Schist detritus. The low carbonate and skeletal content on the SWCM is due to the energetic wave climate and high fluvial supply on the shelves.
A variety of Cr-rich spinels and magnetites are supplied to the SWCM shelves and vary with regional changes in catchment geology. The Cascade shelf is rich in chromites (containing up to 215,000 ppm Cr) and Cr – rich magnetites sourced from the Dun Mountain Ultramafics via the Cascade River. Shelf, beach, and river samples between the Haast River and Waitaha River are dominated by low-Cr magnetite grains which represent the ‘background’ magnetite composition sourced from rivers draining the Alpine Schist dominated catchments. The dispersal of Cr-rich spinels is limited due to the dilution with low Cr-magnetites from rivers and littoral sediments.
Glacio-eustatic lowstands such as the Last Glacial Cold Period (LGCP), represented periods of robust connection of local rivers with the Hokitika and Cook canyon heads, increased interception of littoral transport paths, and compartmentalisation of inter-canyon shelves. Hokitika canyon cores reflect these changes with textural and compositional ‘spikes’ indicating higher terrigenous input during the LGCP. The geochemistry of the terrigenous fraction in the Hokitika canyon provides evidence for enrichment in ferromagnesian and Cr-rich minerals during the LGCP. This is due to the increased connectivity of the Cr-spinel bearing Hokitika River to the canyon head. The Cr/V ratio in particular demonstrates its effectiveness as a proxy for interglacial – glacial change in submarine canyon stratigraphy. Increases and decreases in the connectivity of Cr-bearing fluvial systems during lowstands and highstands respectively can be observed with this ratio.
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Unconsolidated shelf sediments in the area of Scripps and La Jolla Submarine CanyonsWaggoner, James Allen. January 1979 (has links)
Thesis (M.S.)--San Diego State University. / Includes bibliographical references (leaves [61]-65).
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Relating Bedrock Strength to Hydraulic Driving Forces along the Large-Scale Profile of the Colorado River in Glen and Grand CanyonsMackley, Rob D. 01 May 2005 (has links)
The role of bedrock on the longitudinal profile of the Colorado River has intrigued workers for over a century. The river's profile exhibits large-scale (10 to 100 km) variations in geomorphology that are qualitatively associated with changes in rock type. This study provides the first bedrock-strength data to quantitatively test the relation of bedrock-resisting to hydraulic-driving forces in Glen and Grand canyons. The intent of this study is to explore the role, if any, that bedrock has on large-scale geomorphic variations along the profile of the Colorado River. Rock-strength data collected at 84 sites along the river corridor in Glen and Grand canyons include intact-rock strength, fracture spacing , and other characteristics associated with Selby rock-mass strength (RMS). These strength data were statistically related to measurements of channel width, gradient, and calculations of unit stream power.
At the canyon scale (100 km), rocks in Grand Canyon have significantly higher intact-rock strength, lower fracture spacing, and higher RMS than those in Glen Canyon. These observations correspond to the fact that Grand Canyon is steeper and narrower, and has greater mean unit stream power. Furthermore, smaller scale, reach-average values of rock strength correlate significantly to width, gradient, and unit stream power, although there are outliers related to local-scale effects such as rapids. The Colorado River runs in a narrower and steeper channel in reaches confined by resistant bedrock ( e.g., Upper Granite Gorge, RM 77-114). In contrast , reaches floored in weaker bedrock (e.g., lower Marble Canyon, river miles 37 to 58) are associated with wider channels and lower gradient.
This study confirms previous research linking rock type to the geomorphology of the Colorado River. Results imply that knickzones in the profile are persistent features that reflect a dynamic equilibrium between hydraulic-driving and bedrock-resisting forces, rather than transient waves of incision due to tectonics or drainage integration. They support the hypothesis that bedrock sets the long-term, large-scale template for the Colorado River. Bedrock hypothetically acts as a direct control on the river's width and gradient, particularly when the river is in contact with bedrock. Rock-strength and weathering properties of bedrock within tributary catchments, where debris flows initiate, act as an indirect control through their influence on hillslope-to-river sediment production during episodes, such as today, when the river is not on bedrock.
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Space syntax analysis of Chacoan great houses.Cooper, Laurel Martine. January 1995 (has links)
Built form, or human spatial organization, has usually been studied in cultural anthropology and archaeology as dependent on other factors such as social organization. Studies have been limited by a lack of measures permitting comparisons over time and space, so buildings remain little understood despite their visibility in the archaeological record. One approach emerging from multidisciplinary work emphasizes topology over physical characteristics such as shape and size; it examines linkages rather than individual components. The space syntax model of Bill Hillier and the Unit for Architectural Studies at University College London recognizes that spatial patterns are both the product and the generator of social relations. Built form is treated as part of a system of spatial relations, facilitating movement, encounter, and avoidance--both among occupants and between occupants and outsiders. Methods developed through analysis of a broad range of buildings and settlements are available to examine built space and its changes over time. A space syntax model allows a re-examination of great houses in and near Chaco Canyon, New Mexico, built from the mid-A.D. 800s to the mid-1100s. The great houses examined in Chaco Canyon are: Una Vida, Pueblo Bonito, Chetro Ketl, Pueblo del Arroyo, Pueblo Alto, and Kin Kletso. The outliers are Salmon Ruin and West Aztec Ruin. Where sufficient data are available, the control and access features formalized through floorplans are graphed and quantified, allowing comparisons over construction phases and between different sites. The goal is to reevaluate past interpretations, ranging from heavily-populated villages to largely empty redistribution or ceremonial centers. More diversity rather than consistency is apparent from individual great house floor plans, but certain spatial characteristics emerge. Access patterns tend to be asymmetric and non-distributed, becoming deeper over time. Yet the occasional presence of rings, allowing alternate routes within a building, differs from earlier and later building forms. Access patterns differ between and within east and west wings, and the core units, even during comparable time periods. Seen from the perspective of the floor plan, the examples of Chacoan architecture suggest differentiation both within and among great houses.
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A Descriptive Study of Students Who Were Accepted for Admission at West Texas A&M University But Did Not EnrollBarton, Mary Edna 12 1900 (has links)
Each year, institutions of higher education devote valuable financial and personnel resources in the hope of enhancing student recruitment and matriculation. The purpose of this study was to examine the demographic characteristics, the factors that influenced students decisions to apply for admission to a university, their educational intentions, and their reasons for not enrolling after they had been admitted. The subjects of the study were first-time freshmen accepted for admission to a mid-size, public, southwestern university who did not enroll for the fall 1997 semester. Statistically significant differences were found when comparing no-shows and enrolled students by gender, ethnicity, age, ACT/SAT score, and distance of their hometown from the university. There were more female no-shows, and more males enrolled than females; a greater percentage of no-shows reported the distance of their hometown to be more than 200 miles; and the mean test score for no-shows was higher. Factors important in the college selection process found to be statistically significant among the groups were: a greater percentage of Minorities than Caucasians reported the importance of the financial aid award or a scholarship offer; students living within 100 miles of the campus reported the proximity of the university as important, advice received from current or former students and high school counselors was more important to those living more than 100 miles from the campus. Cost of attendance and scholarships were important to students with the higher test scores. Statistically significant reasons cited by the no-shows for not enrolling were more Minorities than Caucasians reported financial difficulties and job demands; students living farther from the campus reported attending other universities while those living within 100 miles reported attending a community college. Recommendations the university studied could pursue include: developing a program to follow-up on the no-shows, directing more energy at recruiting students living within 200 miles of the university, and increasing the availability of scholarships.
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Luminescence Dating of Submarine Canyons: Application to the Monterey Canyon, California / Luminiscensdatering av marina raviner. Tillämpningpå Monterey Canyon, KalifonienHeerema, Catharina January 2016 (has links)
Submarine canyons are major geomorphic features, transporting large quantities of sediments from land to the deep sea. These sediments contain nutrients, enabling life in the deep sea and potentially forming hydrocarbon reservoirs. The transport of sediments towards the deep sea is also important as it links into fundamental concepts of the Earth’s system, such as the global carbon cycle and land surface denudation. Concepts based on the assumption of direct transport of sediments from land to the deep sea. However, how this transport occurs, on what timescales, and if there is potential storage of sediments along the way, is actually poorly known. The current theory is that gravity flow events, such as turbidity events, are the main mechanism behind canyon formation and maintenance. Luminescence dating, an absolute dating method, has been used in an earlier study to look at sediment transport via turbidity currents down the Monterey Canyon, off the coast of California, USA (Stevens et al., 2014). An active upper canyon was found at 1093 metres depth, with frequent events. At 3555 and 3612 metres depth the turbidity events dated were older and indications of major reworking of sediments were found. To pinpoint this change in environments, the present study used luminescence dating in order to get an age estimate of sediments at 2920 meter depth, creating a sequence of ages in the canyon. These cores have captured sediments that have been transported via sand waves, not turbidites. Sand waves are related to the frequent passing of turbidity events, but exact understanding of the mechanisms at hand is poorly understood. Single grain analysis on quartz is used to obtain the individual properties and ages of grains. This gives representative canyon entry ages of the sediments in addition to intrinsic grain properties. The data shows a skewed distribution of grain ages with a narrow, dominant peak between 180 and 240 years within a single core, indicating frequent flushing events and minor reworking of sediments. This is a similar pattern to the core at 1093 meter depth, albeit with increased age, suggesting temporary storage of sediment to at least a depth of 2920 metres. It is proposed that there is a gradual increase in ages down canyon towards 2900 meters depth with a more abrupt transition in environments with increased storage of sediments between 2900 and 3500 meter depth. Sand waves, and the exact relation to turbidites, remain a poorly understood transport mechanisms, but are potentially capable to transport vast amounts of sediments towards the deep sea. / Marina raviner transporterar stora mängder sand från land till havets botten. Men hur sker detta? I nuläget förklaras sandtransport med gravitationsflöde, att gravitationen drar ner sandkornen mot bottnen. Men sker detta vid ett enda stort skede eller i små gradvisa steg? Och kan det vara så att sand, på sin väg till botten, lagras i ravinerna? Det är dessa frågor som jag försöker att kasta ljus på i och med detta projekt.Målet var att komplettera vår kunskap om hur sand förflyttar sig från land till havsbotten genom att studera ifall det har skett en gradvis eller en abrupt transport av sand i ravinen Monterey Canyon vid Kaliforniens kust. Detta har jag gjort genom att datera åldern av sand vid ett djup av 2 920 meter, som i det här fallet deponerats av sandvågor, och sedan jämfört denna ålder med åldrarna på sanden från ett mindre (1 100 m) och större (3 500 m och djupare) djup, vilka analyserades i en tidigare studie (Stevens et al., 2014). Transportmekanism i den studien skiljer sig med min då det rör sig om gravitationsflöden.Med endast några få sandkorn av annan ålder så var den dominerande åldern på kornen i mitt prov mellan 180 till 240 år gamla. Provet vid 1 100 m djup visade sig också ha en liten spridning av ålder vilket tyder på att det skett återkommande utspolning av gammal sand som istället ersatts av ny. Man kan se att det ändå sker en tillfällig lagring av sediment mellan det minsta, studerade djupet och det nyligen tagna provet på 2 900 m, då en svag ökning i ålder kan mätas. Åldern på sandkornen i proven som kom från ett större djup var istället mycket spridd och generellt mycket högre än de från mindre djup. Att det finns en mix av ålder vid ett och samma djup tyder på att sanden vid återkommande tillfällen omfördelats i ravinen.Denna studie antyder att ravinen i fråga är aktiv upp till ett djup av minst 2 920 meter, med bara en svag stegring i ålder med ökande djup. Mellan 2 920 och 3 500 meter ändras miljön vilket gör att sprid-ningen av ålder ökar. Därutöver var det nya provet taget från en plats med ett annorlunda transport-mekanism, sandvågor istället för gravitationsflöde. Sandvågor, och dess relation till gravitationsflöden, är fortsättningsvis en dåligt förstådd transportmekanism som potentiellt är kapabel till att flytta stora mängder sediment till havets botten.
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A preliminary study of the vegetative cover in Spanish Fork Canyon, UtahMarkham, Ben S. 01 January 1939 (has links)
Spanish Fork Canyon is located in central Utah and is part of the Wasatch Mountain range. Since the coming of the white man to this section of country it has been used as a trail. The canyon provides summer range for stock as well as a watershed. Plant densities were determined by the point observation method using series of one-hundred square foot plots. Three areas which have been subject to different grazing uses were studied. The association changes in the canyon are the replacement of sage by slender wheatgrass on the shallow soils and the disclimax condition resulting from over-grazing and fire with the annuals Bromus tectorum and Salsola pestifer replacing the true climax. The sage of protected alluvial fans shows rapid growth recovery and reproduction.
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