43 research outputs found
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Giving a Voice to Those Who Have Silenced Their Own
No full textA production analysis of Bert V. Royal's Dog Sees God: Confessions of a Teenage Blockhead, directed by Sutton Arabe
Hydraulic and chemical properties of geosynthetic clay liners in mining applications
No full text2017 Fall.Includes bibliographical references.Geosynthetic clay liners (GCLs) are thin (< 10 mm) factory manufactured hydraulic barriers used in environmental containment systems because of the propensity of bentonite to swell and immobilize water which results in low hydraulic conductivity, k (≤ 2-3×10-11 m/s). GCLs consist of bentonite (clay) bonded or sandwiched between layer(s) of geotextile and/or geomembrane. The effectiveness of GCLs in containment applications has been demonstrated for systems with low ionic strength solutions and leachates, such as municipal solid waste leachates. Increasingly, GCLs are being used in mining applications; these applications require further research and laboratory testing to demonstrate barrier effectiveness. Existing standard test methods are not well suited for testing of mine-waste-leachates; simple procedures to collect effluent for analysis are lacking, commercially available testing equipment is typically incompatible with extreme pH solutions often encountered, and the use of backpressure is recommended requiring testing at elevated pressures. To overcome these limitations, an alternative gravity method without backpressure, paired with a permeameter constructed from non-reactive materials and intended to minimize clogging was used. Validation of the gravity method is demonstrated through k and hydration testing with synthetic mine waste leachates and comparative tests performed by a standard method. Tests results support that GCLs attain saturation, and that the gravity method does not exhibit uncharacteristically low k due to unsaturated conditions. However, the gravity method revealed the possibility of preferential flow through fiber bundles for GCLs with higher degrees of needle punching which was not observed in standard method tests. The cause of the discrepancy between the two methods is hypothesized to be associated with applying backpressure in the standard method, indicating that the standard method may provide an un-conservative estimate of k for higher peel strength GCLs. Regardless, bentonite saturation is shown to occur without backpressure under conditions typical of k testing, illustrating that saturated (maximum k) tests can be achieved without backpressure. The k of GCLs to synthetic mine leachate solutions was tested using the gravity method with the chemical-resistant permeameter. Three different mine waste leachates are investigated, a neutral pH synthetic gold mining process solution, a high pH synthetic bauxite mining process solution, and a low pH synthetic copper mining process solution. Three different GCL products were also investigated, two higher peel strength GCLs (2170 N/m and 3500 N/m), and a standard peel strength GCL (700 N/m). The preliminary results of k testing are reported
INDIGENOUS LAND TENURE AND LAND USE IN ALASKA: COMMUNITY IMPACTS OF THE ALASKA NATIVE CLAIMS SETTLEMENT ACT
No full textThrough the utilization of qualitative methods such as archival analysis, semi-structured interviewing, comparative and extended case studies, and observation, this paper closely examines two related Alaska Native communities. Our purpose is to document the impact of the Alaska Native Claims Settlement Act of 1971 (ANCSA) on land tenure, land use, and community structure. In all, 41 interviews were conducted, focusing on the following issues: (1) the role of the tribal government in relation to the regional and village corporate structure; (2) the recent changes in traditional land uses; and (3) how group decisions are made regarding land management and distribution of resources. By locating ANCSA within a broader context of economic, political, and cultural globalization that seeks to substitute traditional collective rights in land with individual tenure in a "free market" economy, the findings of this research may carefully and cautiously be applied beyond North America to other indigenous-state struggles regarding control of land and resources.United States. -- [Alaska Native Claims Settlement Act], Indians of North America -- Legal status, laws, etc. -- Alaska, Land tenure -- Law and legislation -- Alaska, Indians of North America -- Alaska -- Claims, Indians of North America -- Land tenure -- Alaska, Indians of North America -- Alaska -- Government relations -- History, Land Economics/Use,
Clergy and Commoners: Interactions between medieval clergy and laity in a regional context
No full textThis thesis examines the interactions between medieval clergy and laity, which were complex, and its findings trouble dominant models for understanding the relationships between official and popular religions. In the context of an examination of these interactions in the Humber Region Lowlands during the thirteenth and early fourteenth centuries, this thesis illustrates the roles that laity had in the construction of official and popular cultures of medieval religion. Laity and clergy often interacted with each other and each other's culture, with the result that both groups contributed to the construction of medieval cultures of religion. After considering general trends through an examination of pastoral texts and devotional practices, the thesis moves on to case studies of interactions at local levels as recorded in ecclesiastical administrative documents, most notably bishops' registers. The discussion here, among other things, includes the interactions and negotiations surrounding hermits and anchorites, the complaints of the laity, and lay roles in constructing the religious identity of nuns. The Conclusion briefly examines the implications of the complex relationships between clergy and laity highlighted in this thesis. It questions divisions between cultures of official and popular religion and ends with a short case study illustrating how clergy and laity had the potential to shape the practices and structures of both official and popular medieval religion
Missing, Presumed Buried? Bone Diagenesis and the Under-Representation of Anglo-Saxon Children
No full textYesSam Lucy (1994: 26) has stated that a `recognised feature of pre-Christian early medieval cemeteries in eastern England is the smaller number of younger burials recovered¿. Although taphonomic factors such as the increased rate of decay of the remains of children and shallow depth of burial have been suggested as possible explanations for this phenomenon, these have been disregarded in favour of cultural influences, with younger children thought to have been disposed of in a different way from adult remains (Lucy, 1994; Härke, 1997; Crawford, 1999). This paper will review the evidence concerning the treatment of the remains of children during the Anglo-Saxon period. It will then review the factors affecting bone preservation, with special reference to the bones of children, and attempt to assess to what extent the under-representation of children in Anglo-Saxon cemeteries can be attributed to bone preservation and soil type. It will show that hypotheses should not be formulated without full consideration of the taphonomy that may affect the completeness of the archaeological record
Diagenesis and geochemistry of the Lower Permian Ingleside Formation, Owl Canyon area, Larimer County, Colorado
No full text2018 Summer.Includes bibliographical references.The purpose of this study is to determine the diagenetic history and timing of hydrocarbon migration in the Lower Permian Ingleside Formation as revealed in the Ingleside roadcut at Owl Canyon area, Colorado. The studied exposure is divided into fourteen beds composed of quartz arenite sandstone, limestone, dolomite, or siltstone. Observations from outcrop and thin sections, including calcite veins, carbonate-hosted vugs, and carbonate cement, suggest carbonate mobility throughout the outcrop. Stylolites parallel to bedding may have formed by pressure solution related to compaction, and pressure solution of carbonates is one possible source of carbonate that could have precipitated in veins or as cement. The formation was affected by other diagenetic processes, in addition to compaction and carbonate cementation, including feldspar dissolution and alteration and several stages of cementation. Cements include hematite, calcite, dolomite, kaolinite, and quartz overgrowth cement. Hematite cement was determined to have precipitated very early. Poikilotopic carbonate cement was precipitated very early, but after the precipitation of the hematite cement. Blocky calcite and blocky dolomite cements, the most common cements within the formation, were precipitated after the hematite and poikilotopic cements. Kaolinite cement was probably precipitated in association with feldspar dissolution and alteration, or occurred with feldspar dissolution during modern weathering. Hydrocarbon migration probably occurred before the precipitation of the blocky carbonate cement. The relationship between S and MgO in some sandstone samples may indicate that Mg and S have been added by diagenetic fluids. Also, K2O correlates with Al2O3 probably because both elements are mainly in the same phases, clay minerals, micas, K-feldspar, or glauconite. This study of the Ingleside outcrop provides some information about the diagenesis, possible timing of possible hydrocarbon migration through the Ingleside Formation, and geochemical and mineralogical composition of the exposure, which was used to interpret the diagenetic history throughout the outcrop. Therefore, this study adds to understanding of hydrocarbon migration and the hydrocarbon pathways in this part of the Denver Basin
Towards a conceptual framework for user-driven semantic metadata interoperability in digital libraries: A social constructivist approach
No full textPurpose – With the aim of developing a conceptual framework which aims to facilitate semantic metadata interoperability, this paper explores overarching conceptual issues on how traditional library information organization schemes such as Online Public Access Catalogues (OPACs), taxonomies, thesauri, and ontologies on the one hand versus Web 2.0 technologies such as social tagging (folksonomies) can be harnessed to provide users with satisfying experiences. Design/methodology/approach –This paper reviews works in relation to current metadata creation, utilization and interoperability approaches focusing on how a social constructivist philosophical perspective can be employed to underpin metadata decisions in digital libraries. Articles are retrieved from databases such as EBSCO host and Emerald and online magazines such as D-Lib and Ariadne. Books, news articles and blog posts that are deemed relevant are also used to support the arguments put forward in this paper. Findings – Current metadata approaches are deeply authoritative and metadata deployments in digital libraries tend to favour an objectivist approach with focus on metadata simplicity. It is argued that unless information objects are enriched with metadata generated through a collaborative and user-driven approach, achieving semantic metadata interoperability in digital libraries will remain difficult. Practical implications – In this paper, it is indicated that the number of metadata elements (fields) constituting a standard has a direct bearing on metadata richness, which in turn directly affects semantic interoperability. It is expected that this paper will contribute towards a better understanding of harnessing user-driven metadata. Originality/value – As suggested in this paper, a conceptual metadata framework which is underpinned by a social constructivist approach substantially contributes to semantic interoperability in digital libraries
The role of organic matter and other soil properties in Zn2+ activity and AB-DTPA-extractable Zn in soils
No full text2000 Spring.Includes bibliographical references.Zinc is a plant micronutrient as well as a potential heavy metal contaminant in soils. In soil solution, the free Zn activity determines the availability of Zn as a micronutrient and its characteristics as a heavy metal contaminant. A better understanding of the mechanism that controls free Zn activity could improve soil treatments of Zn deficiency or toxicity. In this study, Zn2+ activity (measured by chelation) was related to soil properties for 18 alkaline soils from three farms in eastern Colorado. Organic carbon and pH were statistically significant parameters in a regression with log Zn2+ activity. Principal component analysis and path analysis were studied and applied to these soils. Results of principal component analysis showed that the first principal component, summing clay and total soil Zn and subtracting soil carbon, accounted for 52% of the variability in the soils. Soil pH and inorganic carbon dominated the second principal component, which accounted for 32% of the variability. Results of path analysis showed that direct effects of pH, total soil Zn, and organic carbon are important in predicting free Zn activity in these soils. Indirect effects of clay through organic carbon, of inorganic carbon through pH, and between pH and organic carbon were also important. Results from statistical analyses indicate that adsorption of Zn on organic matter may control Zn solubility in soils. To further explore this potential mechanism, Zn adsorption to organic matter was modeled using the chemical equilibrium model, MINTEQA2, and model results were compared to experimental data from the three Colorado farms. Experimental and model results were in close agreement. Adsorption onto organic matter may control Zn solubility in acidic to neutral soils, while precipitation may control Zn in alkaline soils. The AB-DTPA soil test can also be used as a measure of the availability of micronutrients to plants. AB-DTPA-extractable Zn was measured and correlated to soil chemical properties for soil samples described above. Soil organic carbon and total soil Zn were statistically significant parameters in a linear regression with AB-DTPA extractable Zn. Organic matter and clay contents were positively correlated with AB-DTPA-extractable Zn
Composition and fabric of the Kupferschiefer, Sangerhausen Basin, Germany and a comparison to the Kupferschiefer in the Lubin Mining District, Poland
No full text2013 Fall.Includes bibliographical references.The Kupferschiefer, or "copper shale," is a thin carbonaceous marly shale deposited during the Late Permian within the Zechstein Basin of central Europe. A classic example of a sediment hosted stratiform copper deposit, the Kupferschiefer is mineralized with Cu and other metals of economic interest such as Pb, Zn, and Ag. The unit is overlain by the Zechstein Limestone and underlain by the Weissliegend sandstone; it is most well known in Germany and Poland. Overall, the Kupferschiefer in the Sangerhausen Basin in Germany has been less studied than its counterpart in the Lubin mining district in Poland. Some previous studies compare the Kupferschiefer from the Lubin mining district, and more rarely the Sangerhausen Basin, to other stratiform copper deposits, but few compare data from both locations. This study analyzes, compares, and contrasts geochemical, mineralogical, and petrologic data from five Sangerhausen Basin locations and four locations in the Lubin and Rudna mines of the Lubin mining district. A total of 101 samples were examined: 61 Sangerhausen samples (41 from above the Kupferschiefer-Weissliegend contact, and 20 from below the contact) and 41 Lubin mining district samples (28 from above the Kupferschiefer-Weissliegend contact, and 13 from below the contact). Of these, 62 (36 Sangerhausen and 26 Lubin mining district) were geochemically analyzed, and 65 samples were observed in thin section (35 Sangerhausen, 30 Lubin mining district). The Sangerhausen Basin Kupferschiefer exhibits textural, geochemical, and mineralization characteristics broadly similar to those of the Lubin mining district Kupferschiefer, with a few distinct differences. Sulfide mineralization, in the form of disseminated spherules, blebs, aggregates, framboids, and bedding-parallel and -perpendicular veins, is observed in both locations on macro- and microscopic scales. The most abundant sulfide in mineralized samples from both locations is chalcocite, followed by chalcopyrite. Sulfide mineralization is commonly associated with the presence of quartz and carbonate veins in Lubin mining district samples, while mineralization is rarely associated with these veins in Sangerhausen Basin samples. Fluorescence from hydrocarbons is observed in association with sulfide mineralization in some samples, and is generally more common in samples from the Sangerhausen Basin than in those from the Lubin mining district. Both locations show similar geochemical trends with stratigraphic depth, as the units transition from Weissliegend to Kupferschiefer to Zechstein Limestone. The Sangerhausen Basin Kupferschiefer exhibits P2O5 enrichment (averaging 0.26 wt.%) compared to Lubin mining district Kupferschiefer and average shale P2O5 values (averaging 0.13 wt.% and 0.16 wt.%, respectively). Copper concentrations are greater in samples from the Lubin mining district (~14 wt.% max, most samples above ~1 to 2 wt.%) compared to Sangerhausen samples (~10 wt.% max, most samples below 0.5 wt.%). The lower ~25 cm of the Kupferschiefer is enriched in ore metals (Cu, Ag, Pb, Zn, and U) in both locations, and in the Sangerhausen Basin, in middle rare earth elements (REEs) as well. This suggests that the reactions resulting from interaction between fluids migrating from the underlying Weissliegend and overlying Zechstein evaporates mostly occurred in the lower 20 cm of the Kupferschiefer. Assuming that the REEs were carried in the mineralizing fluids, the differences in REE patterns from Sangerhausen samples taken 7 and 8 cm above the basal contact of the Kupferschiefer suggest that even within a single basin the reactions resulting from fluid interaction did not occur at the same stratigraphic level at all locations. The strata-form nature of the deposit suggests large scale bedding-parallel fluid flow. On a smaller scale, the orientation of sulfide, quartz, and carbonate veins and of elongated sulfide macro-blebs suggests that the local, small-scale flow direction is preferentially bedding-parallel as well, especially in the lower 20 to 30 cm of the Kupferschiefer where the matrix is primarily composed of alternating lenses of carbon- and clay-rich pods, and carbonate-rich pods. However, the presence of bedding-perpendicular sulfide blebs and carbonate and quartz veins illustrate that flow was not exclusively bedding-parallel. The Lubin mining district probably experienced at least two pulses of fluid flow, as illustrated by the presence of veins that exhibit alternating carbonate and sulfide precipitation; similar characteristics were not observed in the Sangerhausen Basin samples. The presence of both yellow and blue fluorescence of bitumen in Sangerhausen samples, however, suggests that there were at least two pulses of hydrocarbon migration. The generally well-sorted Lubin mining district Weissliegend was more permeable than the poorly-sorted Sangerhausen Basin Weissliegend
Effect of tailings composition on the shear strength behavior of mine waste rock and tailings mixtures
No full text2014 Fall.Includes bibliographical references.The objective of this study was to evaluate the effect of mine tailings composition on the shear behavior and shear strength of co-mixed mine waste rock and tailings (WR&T). Crushed gravel was used as a synthetic waste rock and mixed with four types of tailings: (1) fine-grained garnet, (2) coarse-grained garnet, (3) copper, and (4) soda ash. Co-mixed WR&T specimens were prepared to target mixture ratios of mass of waste rock to mass of tailings (R) such that tailings "just filled" inter-particle void space of the waste rock (Ropt) prepared at the maximum void ratio of waste rock alone. Triaxial compression tests were conducted on waste rock, tailings, and co-mixed specimens at effective confining stresses (σʹc) of approximately 5, 10, 20, and 40 kPa. Low σʹTcT were selected to assess performance of co-mixed WR&T in final earthen cover applications for waste containment facilities. Waste rock and co-mixed WR&T specimens were 150-mm in diameter by 300-mm tall, whereas tailings specimens were 38-mm in diameter by 76-mm tall. Waste rock was tested with drained and undrained conditions, whereas undrained conditions were used for tailings and co-mixed specimens to reduce testing duration. Shear strength of the WR&T mixtures was comparable to that of waste rock alone. The effective stress friction angle (φʹ) of waste rock was 41°, whereas φʹ of the tailings ranged from 34° (copper) to 41° (soda ash). The WR&T mixtures had an average φʹ = 40° for fine-garnet mixtures and 39° for coarse-garnet and copper mixtures, which are similar to waste rock alone and suggests that the waste rock skeleton controlled shear strength of these mixtures. The soda ash mixtures had a slightly lower φʹ of 38° compared to waste rock alone, which was attributed to clay-sized tailings particles lubricating contacts between waste rock particles. Shear behavior of co-mixed WR&T was controlled by the tailings fraction when tailings were composed of silt and mixed to a ratio of R Ropt, which likely prevented involvement of the tailings fraction in transferring normal and shear stresses. The equivalent granular void ratio (e*), based on the global void ratio (eg) and tailings content, accurately characterized the soil structure of co-mixed WR&T by accounting for the contribution of tailings particles in transferring stress. The equivalent granular state parameter (Ψ*), determined using e*, was able to capture the shear behavior of all waste mixtures. Shear strength behavior of co-mixed WR&T can be predicted using Ψ* provided R, eg, and the steady state line of the WR&T mixture are known
