Browsing by Subject "Limestone"
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Item Biological growth on the Alamo(2009-05) Gallagher, Casey Amber; Gale, Frances R.The limestone façade of the Alamo shows several areas of biological growth with black and gray streaks and blotches discoloring the stone. This thesis investigates the identity of the microorganisms on the stone, using two: DNA identification, and lab cultures grown from samples of the biofilm. By using both approaches, a better understanding was gained of the range of organisms present. Through these tests, it was found that the dominant organism on the limestone is cyanobacteria, of the genus Chrooccocus. Lab cultures revealed other organisms, including possibly fungi photobionts and algae. Through analysis and comparison of historic and contemporary photographs, patterns of recolonization are investigated. To further understand the effects of the biocide treatments, cultured samples were treated, and their reactions monitored. To better understand the possible relationship between the Alamo stone and its colonizing organisms, physical properties of the stone were investigated. SEM images, Edax minerology and water absorption were used to characterize the stone. This study is the first of its kind to investigate Native Texas quarried architectural limestone. Although studies have been conducted on historic monuments around the world to identify biological growth, none have focused on Texas limestone. By using both DNA and lab culture identification, this study adds to a wealth of investigations of other conservation professionals, applying it to a subject that has not been studied in this way before. By understanding the colonizing organisms, a sustainable conservation regimen can be determined.Item Comparison of glycine, acetate, and formate as wettability modifiers for carbonate formations(2021-08-19) Baghishov, Ilgar; Okuno, Ryosuke, 1974-Previous studies indicated the efficacy of the simplest amino acid, glycine, as an aqueous additive for enhanced water imbibition in carbonate reservoirs. The objective of this research was to investigate the importance of the amino group of glycine in its enhanced water imbibition and compare glycine with two carboxylates (acetate and formate) with/without adjusting the solution pH. Contact-angle experiments on calcite were carried out at 347 K and atmospheric pressure with 68000-ppm reservoir brine (RB), and 4 different concentrations of glycine, acetate, and formate solutions in RB. To test the hypothesis that calcite dissolution is one of the main mechanisms in wettability alteration by glycine, we performed another set of contact angle experiments by adding HCl to brine, acetate, and formate solutions. HCl was added to match the pH of the glycine solution at the same concentration. We also performed imbibition tests with Texas Cream Limestone cores at 347 K with brine, glycine, acetate, and formate solutions (with and without HCl) in RB at 5.0 wt%. Contact-angle results indicated that glycine changed calcite’s wettability from oil-wet (120°) to water-wet (45°). However, acetate solution was not able to change the wettability to water-wet; and formate moderately decreased the contact angle to 80°. The increase in pH level during the contact angle experiment with glycine solution indicated the consumption of hydrogen ions because of the calcite dissolution. However, the levels of pH in formate and acetate solutions decreased. Imbibition tests with carbonate cores supported the observations from the contact-angle experiments. The oil recovery factor was 31% for glycine solution, 20% for RB, 21% for formate solution, and 19% for acetate solution. This re-confirmed the effectiveness of glycine as an additive to improve the oil recovery from carbonates. An additional set of imbibition tests revealed that acetate at the pH reduced to the same level as glycine was still not able to recover as much oil as glycine. This showed that glycine recovered oil not only because of the calcite dissolution and the carboxyl group, but also because of the amino group. It is hypothesized that the amino group with its electron donor ability creates a chelation effect that makes glycine entropically more favorable to get attached to the calcite surface than acetate. Another important result is that the formate solution at an adjusted pH resulted in a greater oil recovery than RB or RB at the same pH. This indicates that there is an optimal pH for the carboxyl group to be effective in wettability alteration as also indicated by the pH change during the contact-angle experiment.Item A conditions assessment and treatment recommendations for the main building at the Austin State Hospital(2011-12) Russell, Mary Kelley; Holleran, Michael; Gale, Frances R.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.Item Controls on mixed carbonate-siliciclastic slope and basinal depositional architecture(2022-05-10) Price, Buddy James; Janson, Xavier; Kerans, C. (Charles), 1954-; Mohrig, David; Covault, Jacob; Eberli, Gregor PDeepwater carbonate depositional systems represent historically understudied environments. The Permian Basin provides an advantageous location to re-evaluate these settings due to subsurface data density as well as existing outcrop and subsurface studies providing a framework on which to expand. Regional well log mapping coupled with cores and seismic data highlight a range of carbonate accumulations along the slopes and in the deeper basin indicating a need for updates to current Permian Basin basinal depositional models. Thickness maps and cross sections highlight multiple mounded and elongate carbonate-mud rich accumulations along the western slopes of the Delaware Basin. The mounded nature, lack of platform focused sourcing, and presence of oblique cross-cutting channels suggest these features represent carbonate contourite drifts as opposed to gravity-driven deposits. The drifts extend from the slopes at specific locations corresponding to bathymetric irregularities that likely locally weakened currents, causing deposition. Drift accumulations significantly alter slope geometries but present only one control on slope variation. Additionally, underlying carbonate buildups generates antecedent topography and drives differential compaction which influences platform to basin relief, subsequent slope gradients, and progradation-aggradation ratios. Bottom currents may also locally sweep sediments from toe-of-slope environments, inhibiting progradation. In the deeper basin, mapping highlights previously undocumented calciclastic submarine fans. The fans appear to be point sourced from the platform by antecedent topography, slope reentrants, and regional faults. Some fans extend into the basin over 100km and reach 250m in thickness. The fans range in composition, containing both carbonate debrites and turbidites, and varying volumes of mud-rich siliciclastic turbidites. Runout of gravity flows resulted in concentration of comparatively coarser carbonate material in proximal fan environments and finer siliciclastic mudstone, siltstone, and organic matter in fan fringe environments. This work highlights the first recognition of a carbonate drift system and the expanded interpretation of large-scale calciclastic submarine fans in the Permian Basin. As the Permian Basin represents one of the most heavily studied and geologic data-rich areas in the world, new interpretations of carbonate drift systems and calciclastic submarine fans indicate these systems are likely more common and overlooked in the ancient rock record.Item Douglas Cardinal Guest Lecture(1989-10-23) Cardinal, DouglasAudio files are EID restricted. Individuals without an EID should send an email request to apl-aaa@lib.utexas.edu.Item Effects of Aggregate Gradation and Angularity on VMA and Rutting Resistance(2001-06) Park, Dae-Wook; Chowdhury, Arif; Button, Joe W.The Superpave system adopted the voids in mineral aggregate (VMA) criteria developed by McLeod using the 75-blow Marshall compactor for conventional dense-graded hot mix asphalt (HMA) mixtures. This VMA criteria is a function of only the nominal size of aggregate regardless of shape, texture, or gradation. The Superpave volumetric mixture design process contains a required minimum value for fine aggregate angularity (FAA) as a function of traffic level and position of the layer within the pavement structure. This parameter is reported as the percentage of uncompacted air voids, with larger values generally indicating increased aggregate angularity and, thus, higher VMA and better resistance to permanent deformation. The purpose of this study was to evaluate the effects of FAA and gradation on the resulting VMA of certain HMA mixtures. The effect of FAA was evaluated using mixtures containing coarse limestone combined with six different fine aggregates. Mixtures with three gradations which pass through, above, and below the restricted zone; three different mineral filler contents; and four different values of FAA were analyzed to evaluate the effects of these parameters on VMA of Superpave mixtures. Based on analyses of these tests, mixtures containing fine granite or limestone showed less permanent deformation than mixtures containing fine river gravel or natural rounded sand. FAA values and permanent deformation did not correlate well. Gradations that pass through the restricted zone did not significantly affect mixture VMA. Mineral filler contents and FAA value did affect mixture VMA significantly. Higher FAA values yielded higher VMA.Item Fold-related brittle structures and associated strain in a limestone bed of the Carmel Formation, San Rafael Swell, Utah(2015-12) Laciano, Peter Joseph; Marrett, Randall; Cloos, Mark; Ukar, EstibalitzThe San Rafael Swell (SRS) is a basement-cored Laramide uplift located in central-eastern Utah. The SRS is bounded on the east by a 70 km long monocline, a fault-propagation fold, with excellent exposure of sedimentary strata including the Carmel Formation. This monocline is an ideal natural laboratory for studying brittle deformation associated with folding. Qualitative and quantitative observations for brittle structures in a limestone bed near the base of the Carmel Fm. were made in a wide range of bedding dip, curvature, and fold domains. Kinematic data was collected for 2942 structures (1865 veins, 746 stylolites, 314 faults) in 30 locations in order to calculate principal directions of strain. Additionally, data was collected along 71 scanlines at 19 of those locations in order to estimate structure intensities and strain magnitudes. Dekameter-displacement thrust faults, acting as ramps between inferred layer-parallel faults, accommodate orders of magnitude more strain than all other observed brittle structures. These faults are only found in segments of the monocline where bedding dip is high, but curvature is low, which provides strong evidence that limb rotation more strongly controls strain magnitudes than layer bending in the SRS. The trishear model effectively predicts SRS monocline geometry, specifically observed limb thickening, broad, curved hinges, and progressively rotating limb. This is likely due to the dominance of thick, homogeneous rock packages, such as the Navajo Sandstone, in the SRS monocline. In contrast, strain localization within the Carmel Fm. is poorly predicted by trishear: there is strong evidence of flexural slip, and folding induced structure orientations and calculated principal strain directions remain consistent relative to bedding. These strain directions are inconsistent with trishear forward models produced by workers such as Zuluaga et al. (2014) that do not stay consistent relative to bedding. These divergences are likely due to the fact that trishear is a kinematic model that assumes rock homogeneity, while the Carmel Fm. is stratigraphically and mechanically heterogeneous. Because this heterogeneity appears to have a strong effect on strain localization, kink band models likely better estimate strain localization in the Carmel limestone bed as well as other layers in folded heterogeneous strata. The monocline’s interpreted transition from layer-parallel shortening to extension at the steepest locations in the monocline, and thus at most advanced stage of folding, enabled estimation of the dip of the basement fault beneath the SRS as ~30°. This shallow dip contrasts with the steep dip (~60°) assumed for the SRS by Zuluaga et al. (2014) and observed in the Kaibab uplift (Huntoon and Sears, 1975; Tindall, 2000), but is consistent with a recent estimation of 20-40° for the SRS by Davis and Bump (2009) using trishear modeling.Item Gary Cunningham Guest Lecture(1994-02-28) Cunningham, GaryAudio files are EID restricted. Individuals without an EID should send an email request to apl-aaa@lib.utexas.edu.Item The geology of the building stone of Cedar Park and vicinity(1922-06) Barrow, Leonidas Theodore; Bybee, Halbert Pleasant, 1888-1957Item Limestone slurry scrubbing : modeling and parameter estimation(1995-05) Agarwal, Rajesh Satish; Not availableItem Microbial community structure and nitrogen cycling in limestone biofilms(2015-08) Hancock, Tinisha; Brand, Jerry J. (Jerry Jay), 1941-; La Claire, John W; Leibold, Mathew A; Mehdy, Mona; Nobles, David RBiofilms inhabiting rock surfaces were of particular interest for this study, due to their ubiquity in central Texas and possible role in nitrogen cycling. Biofilm samples from an ornamental pond in Austin, Texas were collected over the course of two and a half years. Microscopic analysis indicated that the general physical structure of the biofilm remained constant, but the organisms inhabiting the biofilm varied. Metagenomic analysis confirmed that taxonomic diversity in biofilm communities is dynamic and variable, but the predicted functional capacities appear to be relatively stable throughout the sampling time. Less than one quarter of the variation in the taxonomic community data is explained by climate variables, indicating that a combination of stochastic and deterministic factors may drive community assembly. Limestone biofilm communities may be colonized from guilds of organisms that assemble based on the functional requirements prescribed by environmental conditions and resource availability. Natural biofilm samples were collected from other distinct patches of limestone in green spaces near Austin. Natural biofilms were thicker and more complex than the ornamental pond biofilms, yet they were not significantly different from each other in terms of their taxonomic community composition. The functional diversity of the natural biofilms was nearly identical to that seen in the ornamental pond biofilms. Taxonomic and functional diversity in natural biofilms were strongly correlated and significantly dissimilar. A strong negative correlation between actinobacteria abundance and bacteroidetes abundance was found, indicating that these organisms might be competitors. Cyanobacteria abundance was positively correlated with both humidity and precipitation, indicating that cyanobacteria might require more water than other organisms in the biofilm community. Organisms within limestone biofilm communities were capable of fixing atmospheric nitrogen, but the rate of nitrogenase activity was highly variable throughout the sampling period. Nostoc was the most abundant and active nitrogen-fixing organism. The abundance of cyanobacteria capable of fixing nitrogen was prone to fluctuation, whereas the abundance of non-photosynthetic nitrogen fixers remained relatively constant. Nitrogenase activity in the light reflects a combined effort between cyanobacterial and other nitrogen fixers and a consortium of other nitrogen fixers may be solely responsible for nitrogenase activity in the dark.Item Microbial influence on the kinetics of karstification(2008-12) Steinhauer, Elspeth Susan; Bennett, Philip C. (Philip Charles), 1959-The traditional model of karst and cave formation is that of carbonic acid limestone dissolution, where biologically-produced CO₂ in meteoric water reacts with and dissolves limestone. However, an alternative model has been proposed for several karst sysems where sulfide is abundant, known as sulfuric acid speleogenesis (SAS). Here, acid produced by chemoautotrophic sulfur-oxidizing bacteria (SOB) corrodes limestone while producing dissolved calcium and sulfate. Little is known about the rate of limestone dissolution due to SOB activity, or the nature of the microbe-limestone attachment and interaction. The field site for this study is Lower Kane Cave, WY, an active SAS-formed cave where rapid steam H₂S oxidation is associated with sulfur-oxidizing microbial mats. In this study, the rate of limestone dissolution due to microbial oxidation of reduced sulfur compounds was investigated using laboratory and field microcosms. Laboratory chemostat chamber experiments were designed to mimic the cave environment with and without SOB (native Kane Cave bacteria and Paracoccus versutus), and using different energy sources (thiosulfate, sulfide, and elemental sulfur stored in bacterial filaments). Limestone dissolution rates of abiotic chemostat experiments from this study are comparable to those in previous literature. However, dissolution rates from the experiments with bacteria are 3-4 times faster than the abiotic control rates, a result which is consistent across duplicate experiments and between experiments using different types of SOB. This rate increase represents a complex chemical system influenced by the bacteria on the mineral surface. SEM images confirm that the limestone chips both in the cave and in the biotic chemostat chambers are uniformly covered in biofilm, and that the mineral surface beneath the biofilm is much more etched and corroded than the surface of limestone chips dissolving without bacteria. The results from the lab experiments and the cave microcosms suggest that a biofilm on limestone chips will physically and chemically separate the mineral surface from the bulk solution. Because the bacteria are generating acid directly on the mineral surface, a microenvironment develops beneath the biofilm with low-pH and low saturation state with respect to calcite. The neutrophilic sulfur oxidizing bacteria found in the cave and used in the experiments benefit from attachment to limestone (high buffering capacity), and create a microenvironment that triggers limestone corrosion at a rate several times faster than the abiotic rate.Item Proprietary Specifications(1988-03-05) Jinkins, Jay (Julius L.)Audio files are EID restricted. Individuals without an EID should send an email request to apl-aaa@lib.utexas.edu.Item Sills and laccoliths(2009-04) Barker, Daniel S.Item Some microscopic characteristics of the Bend and Ellenburger limestones(University of Texas at Austin, 1927) Udden, Johan August, 1859-1932Item Structural diagenesis of bed-parallel and bed-normal fractures, Cretaceous Crato Formation carbonate rocks, NE Brazil(2017-12) McKinnon, Elizabeth Anne; Laubach, Stephen E. (Stephen Ernest), 1955-Here I show that structures exposed in the limestone quarries of the Araripe Basin provide information on the fracture porosity evolution in laminated members of early Cretaceous Brazilian interior basins and provide insight in to the Crato Formation as an analog for offshore reservoirs and its role as a semi-permeable aquitard in the Araripe Basin. Permeable pathways in the microbial laminites of the Crato Formation were enhanced first by fracturing caused by elevated fluid pressures, next by fracturing caused by increasing overburden related to burial, next by jointing caused by decreasing overburden related to uplift and finally by dissolution along joint walls. Porosity was reduced by cementation of fractures, both during and after opening, and later enhanced by dissolution of cements and included host rock within veins. Bed-parallel fractures generated by fluid overpressure may be present in well-layered regions of pre-salt source rocks assuming petroleum generation is significantly high or fluid overpressure occurred sufficiently early in the burial history of pre-salt source rocks. Bed-parallel fractures may serve as storage sites or assist in the lateral transport of fluids to vertical escape pathways. The orientation of bed-normal structures in the Crato Formation is likely different from the orientation of bed-normal structures in pre-salt source rocks due to differences in the basement framework between the Araripe Basin and offshore basins such as the Campos Basin. Open joints are unlikely in subsurface reservoirs due to their relationship with exhumation. According to speleothem growth, open and partially occluded joints in the Crato Formation likely provide permeable pathways for water between the superior and middle aquifers of the Araripe Basin. This fluid movement may be enhanced along bedding planes and/or semi-permeable, bed-parallel gypsum veins with high porosity.Item Surfactant/polymer flood design for a hard brine limestone reservoir(2013-08) Pollock, Trevor Storm; Sharma, Mukul M.A limited number of laboratory studies and pilot programs have been reported in chemical Enhanced Oil Recovery (EOR) flooding of carbonate reservoirs (Adams & Schievelbein, 1987). Fewer still have involved surfactants in limestone reservoirs. No surfactant/polymer flood on a field wide basis of a carbonate reservoir has ever been documented in the literature (Manrique, Muci, & Gurfinkel, 2010). This void represents a colossal opportunity given that nearly a third of the 32 billion barrels of oil consumed in the world each year come from carbonate reservoirs (Sheng, 2011, pp. 1, 254). This thesis is based on experiments with a high hardness (~5,000 ppm divalent ions) carbonate field. Phase behavior, aqueous stability, and core flood experiments were performed using polymer and various surfactants and co-solvents. Both commercially available and laboratory synthesized surfactants were tested. The objective was to optimize the chemical injection design in order to lower interfacial tension between water and oil in the reservoir. Research was also done with alkali intended for use with hard brines. The main challenges when working with hard brine were poor solubilization and low aqueous stability limits. However, highly propoxylated and ethoxylated surfactants mixed with internal olefin sulfonates, hydrophilic sulfates, and sec-butanol were observed to have very high solubilization ratios, fast phase behavior equilibration times, negligible viscous macroemulsion effects, and excellent aqueous stability. Spinning drop interfacial tensiometer tests confirmed low IFT values were obtained for a range of acceptable salinities with hard brine. Three core floods were performed using one of the surfactant formulations developed. One flood was done with field core, brine, and crude oil and failed to meet expectations because of high levels of heterogeneity (vugs) within the core that lead to an elongated oil bank and low and slow oil recovery. The other floods were done with Estillades Limestone. The first Estillades flood used hard synthetic field brine and had better mobility but poor oil recovery. The last core flood had good mobility and recovered 90% of the residual oil to water flooding, but only after a total of 1.1 pore volumes of 1.0 wt% surfactant solution were injected. The results provided in this thesis constitute proof of concept that S/P flooding can be done in high salinity and hardness reservoirs.Item Ted Flato Guest Lecture(1994-02-25) Flato, TedAudio files are EID restricted. Individuals without an EID should send an email request to apl-aaa@lib.utexas.edu.