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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.
101

Structural Geology of Eastern Part of the Malad Summit Quadrangle, Idaho

Shearer, Jay Nevin 01 May 1975 (has links)
The mapped area represents the eastern three-fourths of the Malad Summit Quadrangle, Idaho. It lies mainly in the Bannock Range of southeastern Idaho. The northern and southern margins of the area are 25.5 miles and 17.0 miles, respectively, north of the Idaho-Utah State Line. The Caddy Canyon Formation of Late Precambrian age is the oldest exposed stratigraphic unit. The youngest unit, exclusively of Precambrian age, is the Mutual Formation. The Brigham Formation is considered to be of Late Precambrian to Early Cambrian(?) age. Younger formations of Cambrian to Silurian age are present. The Precambrian units, as well as the Brigham, consist chiefly of quartzite. Younger Paleozoic units are primarily limestone and dolomite. The Precambrian and Paleozoic units are unconformably overlapped by the Wasatch and Salt Lake Formations of Tertiary age. A major thrust fault is widely exposed in the mapped area. It places various formations of early Paleozoic age in thrust contact with the Brigham Formation. Several minor thrust faults are also present. The thrust faulting is related to the Laramide orogeny which was active in western United States from late Jurassic into Eocene. Normal faults, in the mapped area, trend generally north-south x and east-west. The north-south faults, characteristic of the Basin and Range province, are responsible f or most of the relief in the area. The normal faulting began as early as Oligocene and has continued intermittently to the present.
102

Sedimentologic and geophysical study of the stratigraphy and development of modern carbonate Islands, Cotton Key, Florida

Hudley, Joel Wayne. January 2006 (has links)
Thesis (M.A.)--State University of New York at Binghamton, Geological Sciences and Environmental Studies Department, 2006. / Includes bibliographical references.
103

Study on the dissolution of lime and dolomite in converter slag

Deng, Tengfei January 2012 (has links)
In the present study, the dissolution mechanism and rate of lime, limestone and dolomite in converter slag was studied. Lime dissolution in stagnant slag was studied first and dissolution of lime, limestone and dolomite under forced convection were carried out by new experimental setup. Dissolution of different CaO samples into stagnant converter slags was carried out in a closed tube furnace at 1873K. In the case of CaO-‘FeO’-SiO2 slag, the dissolution of CaO rod in the stagnant slag was retarded after the initial period (2 minutes). A dense layer of 2CaO∙SiO2 was found to be responsible for the total stop of the dissolution. It could be concluded that constant removal of the 2CaO∙SiO2 layer would be of essence to obtain high dissolution rate of lime. In this connection, it was found necessary to study the dissolution of lime in moving slag. In order to obtain reliable information of lime dissolution under forced convection, the commonly used rotating rod method was examined. Both CFD calculation and cold model experiments showed evidently that the mass transfer due to radial velocity introduced by forced convection was zero if the rod was centrally placed in a cylindrical container. A new experimental design was therefore developed. A cube was placed in the crucible and stirred by Mo rod along with slag. The whole system could be quenched in order to maintain the state of the system at high temperature. A linear relationship between normalized length and time was obtained for lime dissolution. Different lime samples showed big difference in dissolution rate. It was found that the main mechanism of CaO dissolution in slag was due to the removal of 2CaO∙SiO2 layer. Decomposition and dissolution of limestone and dolomite in slag at 1873 K were studied. The decomposition was carried out both in argon and in slag under argon atmosphere. The decomposition process was simulated using Comsol. The results showed evidently that the decomposition of limestone and dolomite was controlled mostly by heat transfer. It was also found that the decomposition of limestone product: CaO had very dense structure, no matter the sample was decomposed in slag or in argon. The slow decomposition and the dense CaO layer would greatly hinder the dissolution of lime in the slag. The present results clearly indicate that addition of limestone instead of lime would not be beneficial in converter process. Discontinuous 2CaO∙SiO2 layer along with MgO∙Fe2O3 particles was found on the surface of the dolomite sample. Some 2CaO∙SiO2 islands were found in the vicinity of the sample in the slag, which revealed therefore that the dissolution was dominated by the peeling-off of the layer of 2CaO∙SiO2-MgO∙Fe2O3 mixture. 2CaO∙SiO2, (Mg, Fe)Oss along with super cooled liquid phases were found inside dolomite sample close to the surface. 2CaO∙SiO2 phase was replaced gradually by 3CaO∙SiO2 towards the centre of the decomposed sample. / <p>QC 20120829</p>
104

A conditions assessment and treatment recommendations for the main building at the Austin State Hospital

Russell, Mary Kelley 22 February 2012 (has links)
This report addresses building envelope conditions of the Main Building of the Austin State Hospital (ASH), formerly the Texas Lunatic Asylum. Designed in 1857 to be constructed in phases and follow the nationally recognized Kirkbride plan, this four-story, solid limestone wall building remained a patient dormitory for almost a century. At present, the Main Building serves as the administration building for the ASH campus but has experienced deterioration due to inappropriate repairs and neglect as a result of inadequate funding. This report provides a historical record of the Main Building, documents existing exterior conditions, discusses mechanisms of deterioration for conditions and provides selected treatment recommendations. Observed conditions include biological growth, iron staining, limestone erosion, and inappropriate repairs with portland cement. / text
105

Geochemical evolution of groundwater in the Pleistocene limestone aquifer of Barbados

Jones, Ian Christopher 28 August 2008 (has links)
Not available / text
106

The origin of chert in the Concha Limestone (Permian) of southeastern Arizona

Ervin, Mary Teresa, 1956- January 1986 (has links)
No description available.
107

A description of the limestone blocks of the Tucson Mountain Chaos, Pima County, Arizona

McCoy, Scott, 1939- January 1964 (has links)
No description available.
108

XERIC LIMESTONE PRAIRIES OF EASTERN UNITED STATES

Lawless, Patrick Joseph 01 January 2005 (has links)
Xeric limestone prairies (XLPs) are open, nonforested communities dominatedby native, C4 perennial grasses. In eastern United States, they occur on shallow, rockycalcareous soils in various physiographic provinces from Missouri and Pennsylvaniasouth to Arkansas and Georgia. Floristic, vegetation, and physical environmental datawere collected from 18 XLPs in Kentucky and used in conjunction with data collected inother studies to provide a synthesis for XLP vegetation in eastern United States and acomparison of this vegetation type with limestone cedar glades and deep-soil barrens.XLPs occur on 33 soil series in five orders (Alfisols, Mollisols, Ultisols, Inceptisols, andVertisols) and on limestone, dolomite, and calcareous shale of Cambrian through Tertiarysystems. In Kentucky, XLPs are restricted to the Interior Low Plateaus, where they aremost frequent on the Upper Mississippian Salem Limestone in the KnobstoneEscarpment and Knobs. Three hundred and thirty-five taxa were recorded in the 18 sitessampled in Kentucky, of which 20 (6.0%) are nonnative and 24 (7.2%) state-listed asrare. The majority of the flora is intraneous C3 hemicryptophytes. Thirteen taxa areendemic to XLPs of eastern United States, but none to those in Kentucky. The native, C4perennial grass Schizachyrium scoparium was dominant in 10 of 12 community types inKentucky identified at a scale of 100-m2 and in 21 of 23 studies of XLPs in easternUnited States. The C4 annual grass Sporobolus vaginiflorus had high frequency values inthe majority of sites in Kentucky, where it often was dominant in the most shallow-soilzones. Variability among XLPs in Kentucky and among the floras of XLPs in differentregions is largely attributable to differences in forb species composition. Soil depth is theprimary abiotic source of variability in XLP community types in Kentucky and in manyother regions of eastern United States. Dendrochronological and aerial photographicstudies support the conclusion that the vast majority of XLPs are not primarycommunities. XLPs on the Cambrian Ketona Dolomite in the Ridge and Valley in BibbCounty, Alabama, are perhaps the only sites which represent an edaphic climax.
109

Alvar in the post industrial: (re) introducing alvar plant communities in the inwood quarry

Johnson, Kaila 05 September 2014 (has links)
This practicum investigates the reintroduction of a globally recognized at-risk plant community, Alvar, into an abandoned limestone quarry, located in the town of Inwood, in the Interlake Region of Manitoba. Alvar develops naturally over the course of thousands of years, and also naturally exists on exposed limestone bedrock, which is subsequently one of the greatest indicators of suitable areas for limestone quarrying. By utilizing recent techniques proven to be effective in Alvar regeneration, this practicum focuses on the landscape architect as a pivotal tool in creating a functional landscape, both in terms of environmental, social, and economic integrity. Using an ecotourism-based approach to engage the public with the site, while creating a platform for Alvar regeneration and future scientific research initiatives provides an economic, ecological, and social solution to some of the most negatively viewed aspects of the area. This practicum offers an alternative solution to traditional quarry rehabilitation strategies as well as the at-risk Alvar plant communities: strengthening it by reintroducing it in a post-industrial landscape, while raising awareness about its historic and ecological significance in an ecotourism-based outlet.
110

Effect of ultraviolet light on the removal of red acrylic paint from limestone / Title on signature form: Effects of ultraviolet light on the removal of red acrylic paint from limestone

Biggio, Elizabet T. 04 May 2013 (has links)
Graffiti is a near constant problem for historic structures and monuments, particularly in urban environments. Currently available non-destructive techniques are not always adequate for graffiti removal. Acrylic spray paints, the most common graffiti material, are composed of polymers which are subject to degradation by ultraviolet light. The feasibility of using this mechanism as a tool for graffiti removal was explored through practical experiments. Red acrylic paint was sprayed onto samples Indiana limestone which were then exposed to UV-B light sources for two, four, and six weeks. Following exposure, samples were scrubbed with acetone, a common solvent used in graffiti removal. Relative differences in the paint removal on the treated and untreated sides were observed, with more paint being removed from the treated sides in some cases. Additional samples were coated with titanium dioxide and exposed to ultraviolet light, yielded a greater level of overall paint removal. It was concluded that this mechanism offers promise and warrants further study. / Department of Architecture

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