Matching Items (201)
Description
Hydraulic fracturing, or fracking, has become a common practice in United States oil fields for enhancing their productivity. Among the concerns regarding fracking, however, is the possibility that it could trigger shallow earthquakes. The brine that results from fracking is injected into the subsurface for disposal. This brine causes a pore pressure gradient that is commonly believed to trigger failure along critically stressed subsurface faults. In Timpson, a small city in eastern Texas, earthquakes have become much more common since two injection wells were installed in 2007. 16 events of M_W > 2 have been detected since 2008 and are believed to be associated with failure along a subsurface fault. Applying interferometric synthetic aperture radar, we analyzed 3 sets of SAR images from the Advanced Land Observing Satellite (ALOS) from May 2007 to December 2010. Using these data sets, XX interferograms were generated. From these interferograms, it was possible to determine the spatial and temporal evolution of the crustal deformation in the line-of-sight of the satellite. The results show strong evidence of uplift in the region adjacent to the injection wells. While previous studies have established a strong connection between fluid injection and increased seismicity, this is to our knowledge the first observed case of crustal deformation that has been observed as a result of hydraulic fracturing fluid disposal.
ContributorsSedlak, Alexander Paul Woodward (Author) / Shirzaei, Manoochehr (Thesis director) / Vivoni, Enrique (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / Department of Chemistry and Biochemistry (Contributor) / School of Geographical Sciences and Urban Planning (Contributor) / School of Earth and Space Exploration (Contributor)
Created2014-05
Description
Many radioactive decay schemes employed in geochronology prove imprecise when placing accurate age constraints on young basalt flows. The (U-Th)/He systematics of detrital zircon and apatite within baked zones is examined as an alternative. Parent-daughter radioisotope ratios within grains from baked zones can completely reset if subjected to temperatures high enough and long enough for bulk diffusive loss. Presented here is the reproducibility of initial attempts to date flows by examining the (U-Th)/He geochronology of grains within baked zones. We examine grains from two localities within the San Francisco Volcanic Field and the Mormon Volcanic Field in northern Arizona. Thirteen zircon and apatite grains yielded from locality 2 collected from the uppermost 10 cm beneath a 7m flow of a basalt yield an apparent age of 4.39 ± 0.28 Ma (2σ), which is within range of published Middle Pliocene ages. Twenty-nine grains from locality 1 collected from the uppermost 20 cm beneath a 2 to 5m flow yield dates ranging from 0.47 ± 0.02 Ma to 892.77 ± 27.02 Ma, indicating the grains were partially reset or not reset at all. The degree to which grains are reset depends on a variety of factors detailed in this study. With these factors accounted for however, our study confirms application of this indirect dating technique is a useful tool for dating basaltic flows.
ContributorsCronk, Stephanie Sarah (Author) / Hodges, Kip (Thesis director) / van Soest, Matthijs (Committee member) / Barrett, The Honors College (Contributor) / School of Earth and Space Exploration (Contributor)
Created2014-05
Description
Blue Mound State Park, located in the state of Wisconsin (USA), is host to a topographic anomaly known as Blue Mound. This mound is the western of the two mounds that make up the park, and it marks the highest elevation in southern Wisconsin. Unlike its eastern sibling, Blue Mound possesses an unusual chert cap that may have protected it from erosion, thus preserving its stratigraphic integrity. Although Blue Mound's unique chert armor was noted in 1927 by the Wisconsin Geological and Natural History Survey, no published work has satisfactorily explained its origin. As little was known about the formation of cherts until the mid-to-late 1900s, the Blue Mound cap was classified merely as a Silurian dolostone into which chert had somehow become integrated (Steidtmann). However, the published observations of the Blue Mound chert do not necessarily match with the classification granted by the Wisconsin Geological and Natural History Survey, nor were any convincing interpretations offered regarding the presence of the chert. Since 1927, significant progress in the field of sedimentology has been achieved. There now exists knowledge that may fill the gaps between observation and interpretation in the Blue Mound survey. The observations in the 1927 bulletin correspond with modern notions of a paleokarst chert breccia, which forms a chert rubble or residuum. A chert breccia is formed when existing clasts, or pieces, of chert become cemented together by further chert deposition (Kolodny, Chaussidon and Katz). This can form large boulders of chert rubble that resist erosion. Accumulation of chert rubble has been documented to form along old weathering surfaces as an insoluble residue in environments similar to Blue Mound (Kolodny, Chaussidon and Katz). The purpose of this investigation was to verify the observations within the 1927 survey of the Blue Mound chert, and determine through field observations and sample study if the Blue Mound chert fits the model of a paleokarst chert breccia.
ContributorsGalarowicz, Calley (Author) / Knauth, Paul (Thesis director) / Semken, Steven (Committee member) / Martin, Thomas (Committee member) / Barrett, The Honors College (Contributor) / School of Earth and Space Exploration (Contributor)
Created2013-05
Description
Understanding more about the similarities and differences in cultural perceptions of climate change-related disease causation can better inform culturally specific public health measures. Using interviews conducted with 685 adults in eight diverse global locations ranging from Fiji and China to England and Phoenix, Arizona, this study explores climate change-disease beliefs within and across diverse cultures and comparisons between cultural and scientific models. A cultural consensus analysis was employed to identify a "culturally correct" model for each study site. Next, a scientific model was generated based on current scientific consensus regarding climate change- disease connections. Using the Quadratic Assignment Procedure (QAP), we determined the amount of correlation shared between the scientific model and each cultural model. The analysis revealed a high level of intercorrelation between the models of English speaking, economically developed sites such as Phoenix, Arizona. Additionally, cultural models from the non-English speaking sites were highly intercorrelated with one another. Overall, the English speaking sites tended to have more complex models with a greater density of causal links. Cultural models from the English speaking sites also demonstrated high levels of correlation with the scientific model. In comparison, the cultural models from the non-English speaking sites exhibited little correlation with the scientific model. Based on these findings, we suggest that cultural beliefs related to climate change-related disease causation may be influenced by complex local factors. For example, differences in education and media influences along with localized differences in climate change impacts may, in part, contribute to divergences between the cultural models.
ContributorsMcAlister, Alyssa Brittney (Author) / Wutich, Amber (Thesis director) / Brewis Slade, Alexandra (Committee member) / Barrett, The Honors College (Contributor) / School of Earth and Space Exploration (Contributor) / School of Human Evolution and Social Change (Contributor) / School of Mathematical and Statistical Sciences (Contributor)
Created2014-05
Description
There are many outstanding questions regarding the petrologic processes that give rise to andesitic and basaltic magmas in subduction zones, including the specifics that govern their geographical distribution in a given arc segment. Here I investigate the genesis of calc-alkaline and tholeiitic basalts from the Lassen Volcanic Center in order to determine the pressure, temperature, source composition, and method of melting that lead to the production of melt in the mantle below Lassen. To this aim, a suite of primitive basalts (i.e. SiO2<52 and Mg#>65) are corrected for fractional crystallization by adding minerals back to the bulk rock composition with the goal of returning them to a primary composition in equilibrium with the mantle. Thermobarometry of the primary melt compositions is conducted to determine temperature and pressure of melting, in addition to a forward mantle modeling technique to simulate mantle melting at varying pressures to constrain source composition and method of melting (batch vs. fractional). The results from the two techniques agree on an average depth of melt extraction of 36 km and a source composition similar to that of depleted mantle melted by batch melting. Although attempted for both calc-alkaline and tholeiitic basalts, the fractional crystallization correction and thus the pressure-temperature calculations were only successful for tholeiitic basalts due to the hydrous nature of the calc-alkaline samples. This leaves an opportunity to repeat this study with parameters appropriate for hydrous basalts, allowing for the comparison of calc-alkaline and tholeiitic melting conditions.
ContributorsSheppard, Katherine Davis (Author) / Till, Christy (Thesis director) / Hervig, Richard (Committee member) / Barrett, The Honors College (Contributor) / School of Earth and Space Exploration (Contributor)
Created2015-05
Description
In an effort to gauge on-campus resident's satisfaction with services provided by Century Link and the University Technology Office as well as understand the resident's technology usage habits, the Performance Based Research Studies Group at ASU conducted a survey to collect the data needed to initiate improvements. Unlike previous years, the 2015 edition of the survey was distributed more efficiently by engaging University Housing staff members (those who work closest with the residents). The result was a 288% increase in responses from the previous year, totaling 2352 respondents and a 167% increase in the number of Residential Halls surveyed, totaling 24. As a primary concern, on a scale of zero to five, the average Internet satisfaction rating was 2.42. In the comments section residents reported issues with the reliability and speed of the ASU networks. It was further determined that residents were dissatisfied with the television services with an average satisfaction rating of 2.91; and the vast majority of comments regarding television services demanding that the ESPN channels be provided. In addition to the metrics on resident satisfaction, it was found that the majority of on-campus residents do not utilize hard-wired ports. Based on the information gathered from this survey, it is recommended that the University Technology Office: 1) focus efforts on upgrading, expanding, and improving the existing ASU networks in particular the reliability and speed of those networks, 2) invest in a broader channel line-up to at minimum provide the ESPN channels, and 3) start an awareness campaign to educate residents on the usage of hard wired ports with the goal of increasing hard wired port usage. As a corollary to information gathered from the survey, it is possible to begin building technology usage profiles on each building and even building such profiles on each residential college and academic unit to better understand the clientele and adapt the services a necessary.
ContributorsMcculloch, John Patrick (Author) / Kashiwagi, Dean (Thesis director) / Kashiwagi, Jacob (Committee member) / Barrett, The Honors College (Contributor) / School of Earth and Space Exploration (Contributor) / Department of Information Systems (Contributor) / School of Mathematical and Statistical Sciences (Contributor)
Created2015-05
Description
Membrane proteins located within or as attachments to the cell membrane play critical roles in many essential cellular functions and host-pathogen interactions. Knowledge of the structure and function of membrane proteins in pathogenic species can allow for the development of specific vaccines and therapeutic agents against the pathogen. Francisella tularensis is an intracellular pathogen that is the causative agent of the severe, life-threatening infection, tularemia, in humans and other small mammals. F. tularensis is prevalent within the environment and is a potential bioterrorism agent due to its high virulence and its ability to be spread easily as an aerosol. The CapBCA membrane protein complex has been identified as a virulence factor of F. tularensis. This project, derived from the Membrane Proteins in Infections Diseases (MPID) Project, aims to successfully express the membrane proteins CapBCA, which are crucial to the pathogenic properties of F. tularensis. To accomplish this goal, methods for in vivo recombinant expression and purification of membrane proteins are in the process of being developed. The expression of the CapA component has been successful for some time, therefore, the goal of this study is to develop an approach toward recombinant in vivo membrane protein expression of both the CapB and CapC components of the CapBCA membrane protein complex. In this study, the CapB and CapC components were expressed for the first time in vivo through the use of the novel MPID vector, pelB-MBP. The expression of the CapB and CapC components will allow for large-scale expressions to commence with the end goal of determining the crystal structures of the individual proteins or the complex. Ultimately, it is hoped that knowledge of these molecular structures can lead to the development of a vaccine or other therapeutic agents against this pathogen.
ContributorsTrimble, Kelli Lauren (Author) / Fromme, Petra (Thesis director) / Hansen, Debra (Committee member) / Barrett, The Honors College (Contributor) / Department of Chemistry and Biochemistry (Contributor) / School of Film, Dance and Theatre (Contributor)
Created2015-05
Description
Spacebound is a mobile application that helps people understand astronomical distances by converting their distances walked on Earth to an interstellar scale. To better navigate outer space, the app presents predefined distance scales and journeys with various objects (planets, asteroids, stars) to explore. Spacebound hopes to be a gamified approach for exploring outer space and also an educational app where the user can learn more about objects as they visit them.
ContributorsSadachar, Shivam (Author) / O'Rourke, Joseph (Thesis director) / Loyd, Parke (Committee member) / Melodie, Kao (Committee member) / Computer Science and Engineering Program (Contributor) / School of Earth and Space Exploration (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
Description
Drylands, though one of the largest biomes, are also one of the most understudied biomes on the planet. This leaves scientists with limited understanding of unique life forms that have adapted to live in these arid environments. One such life form is the hypolithic microbial community; these are autotrophic cyanobacteria colonies that can be found on the underside of translucent rocks in deserts. With the light that filters through the rock above them, the microbes can photosynthesize and fix carbon from the atmosphere into the soil. In this study I looked at hypolith-like rock distribution in the Namib Desert by using image recognition software. I trained a Mask R-CNN network to detect quartz rock in images from the Gobabeb site. When the method was analyzed using the entire data set, the distribution of rock sizes between the manual annotations and the network predictions was not similar. When evaluating rock sizes smaller than 0.56 cm2 the method showed statistical significance in support of being a promising data collection method. With more training and corrective effort on the network, this method shows promise to be an accurate and novel way to collect data efficiently in dryland research.
ContributorsCollins, Catherine (Author) / Throop, Heather (Thesis director) / Das, Jnaneshwar (Committee member) / Aparecido, Luiza (Committee member) / School of Earth and Space Exploration (Contributor) / School of Art (Contributor) / School of International Letters and Cultures (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
Description
The Star Planet Activity Research CubeSat (SPARCS) will be a 6U CubeSat devoted to photometric monitoring of M dwarfs in the far-ultraviolet (FUV) and near-ultraviolet (NUV) (160 and 280 nm respectively), measuring the time-dependent spectral slope, intensity and evolution of M dwarf stellar UV radiation. The delta-doped detectors baselined for SPARCS have demonstrated more than five times the in-band quantum efficiency of the detectors of GALEX. Given that red:UV photon emission from cool, low-mass stars can be million:one, UV observation of thes stars are susceptible to red light contamination. In addition to the high efficiency delta-doped detectors, SPARCS will include red-rejection filters to help minimize red leak. Even so, careful red-rejection and photometric calibration is needed. As was done for GALEX, white dwarfs are used for photometric calibration in the UV. We find that the use of white dwarfs to calibrate the observations of red stars leads to significant errors in the reported flux, due to the differences in white dwarf and red dwarf spectra. Here we discuss the planned SPARCS calibration model and the color correction, and demonstrate the importance of this correction when recording UV measurements of M stars taken by SPARCS.
ContributorsOsby, Ella (Author) / Shkolnik, Evgenya (Thesis director) / Ardila, David (Committee member) / School of Earth and Space Exploration (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05