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Geology and its tangential studies, collectively known and referred to in this thesis as geosciences, have been paramount to the transformation and advancement of society, fundamentally changing the way we view, interact and live with the surrounding natural and built environment. It is important to recognize the value and importance

Geology and its tangential studies, collectively known and referred to in this thesis as geosciences, have been paramount to the transformation and advancement of society, fundamentally changing the way we view, interact and live with the surrounding natural and built environment. It is important to recognize the value and importance of this interdisciplinary scientific field while reconciling its ties to imperial and colonizing extractive systems which have led to harmful and invasive endeavors. This intersection among geosciences, (environmental) justice studies, and decolonization is intended to promote inclusive pedagogical models through just and equitable methodologies and frameworks as to prevent further injustices and promote recognition and healing of old wounds. By utilizing decolonial frameworks and highlighting the voices of peoples from colonized and exploited landscapes, this annotated syllabus tackles the issues previously described while proposing solutions involving place-based education and the recentering of land within geoscience pedagogical models. (abstract)

ContributorsReed, Cameron E (Author) / Richter, Jennifer (Thesis director) / Semken, Steven (Committee member) / School of Earth and Space Exploration (Contributor, Contributor) / School of Sustainability (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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For the geoscience community to continue to grow, students need to be attracted to the field. Here we examine the Incorporated Research Institutions for Seismology (IRIS) Research Experience for Undergraduates (REU) program to understand how the participants' experiences' affects their interest in geoscience and educational and career goals. Eleven interns

For the geoscience community to continue to grow, students need to be attracted to the field. Here we examine the Incorporated Research Institutions for Seismology (IRIS) Research Experience for Undergraduates (REU) program to understand how the participants' experiences' affects their interest in geoscience and educational and career goals. Eleven interns over two years (2013-2014) were interviewed prior to the start of their internship, after their internship, and after presenting their research at the American Geophysical Union annual meeting. This internship program is of particular interest because many of the interns come into the REU with non-geoscience or geophysics backgrounds (e.g., physics, mathematics, chemistry, engineering). Both a priori and emergent codes are used to convert interview transcripts into quantitative data, which is analyzed alongside demographic information to understand how the REU influences their decisions. Increases in self-efficacy and exposure to multiple facets of geoscience research are expressed as primary factors that help shape their future educational and career goals. Other factors such as networking opportunities and connections during the REU also can play a role in their decision. Overall, REU participants who identified as geosciences majors solidified their decisions to pursue a career in geosciences, while participants who identified as non-geosciences majors were inclined to change majors, pursue geosciences in graduate school, or explore other job opportunities in the geosciences.
ContributorsGossard, Trey Marshall (Author) / Semken, Steven (Thesis director) / Garnero, Edward (Committee member) / Reynolds, Stephen (Committee member) / School of Earth and Space Exploration (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
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Though large amounts of nitrogen are allocated to the Earth's mantle, not much is known concerning how it is stored and transported. In this study, stishovite is proposed as a host for nitrogen within the Earth's deep interior. Stishovite was synthesized and heated under nitrogen rich conditions using diamond-anvil cell

Though large amounts of nitrogen are allocated to the Earth's mantle, not much is known concerning how it is stored and transported. In this study, stishovite is proposed as a host for nitrogen within the Earth's deep interior. Stishovite was synthesized and heated under nitrogen rich conditions using diamond-anvil cell equipment and double-sided laser heating. Synthesis pressures ranged from 16 to 44 GPa and temperatures centered at ~1800 K. Experimental products were removed from diamond anvil cells and analyzed for nitrogen content via SIMS and SEM/EDX analysis. Unit cell parameters were obtained through XRD analysis. N solubility in stishovite was calculated to be up to 1.54 wt % from SIMS data through the use of an ion implant and a relative sensitivity factor. XRD data indicated a decrease in unit cell volume at higher pressures, with the c-axis length showing larger compressibility than the a-axis length. Through SEM and EDX analysis, a uniformly low level of N was observed throughout the sample indicating that N was uniformly incorporated into the crystal structure of stishovite. The data suggests that, rather than existing separately from stishovite as a silicon or carbon nitride, N has substituted into the crystal structure of stishovite. Both O and N have largely similar atomic radii, with N being slightly smaller, indicating that N can substitute for O. With the levels of N observed in the experiment, it is implicated that the mantle has an extremely large storage capacity for N. Further experimentation, with the addition of TEM analysis, should be conducted in order to determine the effects of pressure and temperature on the solubility of N in stishovite. Additionally, substitution of N as HN into stishovite should be investigated as HN accounts for the charge imbalance seen when substituting N for O.
ContributorsNoble, Shaela Marie (Author) / Shim, Sang-Heon (Thesis director) / Hervig, Richard (Committee member) / School of Life Sciences (Contributor) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor) / School of Earth and Space Exploration (Contributor)
Created2016-05
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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

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
Description
Gamma-ray bursts (GRBs) are a type of astrophysical transient resulting from the most energetic explosions known in the universe. The explosions occur in distant galaxies, and their bright initial emission may only last a few seconds. Colibri is a telescope being built at the San Pedro Martir

Gamma-ray bursts (GRBs) are a type of astrophysical transient resulting from the most energetic explosions known in the universe. The explosions occur in distant galaxies, and their bright initial emission may only last a few seconds. Colibri is a telescope being built at the San Pedro Martir Observatory in Baja, CA, MX with high sensitivity in order to study these events at a high redshift. Due to how quickly GRBs occur, it is essential to develop an image reduction pipeline that can quickly and accurately detect these events. Using existing image reduction software from Coatli, which was programmed and optimized for speed using python, numerous time trials were performed in order to determine if the pipeline meets the time requirements with various factors being adjusted. The goal of this experiment is for the telescope to respond to, capture, and reduce the images in under 3 minutes. It was determined that the reduction was optimized when the number of files to be reduced was set equal to 16 or higher by changing the batch number and the blank sky subtraction function was performed. As for the number of exposures, one can take up to four 30 second exposures or twenty 5 second exposures and reduce them in under 3 minutes.
ContributorsHeiligenstein, Wren (Author) / Butler, Nathaniel (Thesis director) / Jansen, Rolf (Committee member) / Dimitrova, Tzvetelina (Committee member) / Barrett, The Honors College (Contributor) / School of Earth and Space Exploration (Contributor)
Created2024-05