ASU Electronic Theses and Dissertations
This collection includes most of the ASU Theses and Dissertations from 2011 to present. ASU Theses and Dissertations are available in downloadable PDF format; however, a small percentage of items are under embargo. Information about the dissertations/theses includes degree information, committee members, an abstract, supporting data or media.
In addition to the electronic theses found in the ASU Digital Repository, ASU Theses and Dissertations can be found in the ASU Library Catalog.
Dissertations and Theses granted by Arizona State University are archived and made available through a joint effort of the ASU Graduate College and the ASU Libraries. For more information or questions about this collection contact or visit the Digital Repository ETD Library Guide or contact the ASU Graduate College at email@example.com.
- Till, Christy B
- 4 Arizona State University
- 2 Hervig, Richard L
- 2 Roggensack, Kurt
- 1 Allison, Chelsea M
- 1 Bell III, James F
- 1 Christensen, Philip R
- 1 Clarke, Amanda B
- 1 Desch, Steven J
- 1 Perez, Alexandra Marie
- 1 Regier, Margo Regier
- 1 Robinson, Mark S
- 1 Schrader, Devin L
- 1 Semken, Steven
- 1 Sharp, Thomas G
- 1 Wellington, Danika
- 4 English
- 4 Public
Volcanic devolatilization is one of the major processes in the global nitrogen cycle. Past studies have often estimated the magnitude of this flux using volcanic emission measurements, which are limited to currently active systems and sensitive to atmospheric contamination. A different methodological approach requires appropriate analytical parameters for nitrogen analysis in silicate glasses by secondary ion mass spectrometry (SIMS), which have not yet been established. To this end, we analyze various ion implanted basaltic and rhyolitic glasses by SIMS. We demonstrate that water content significantly affects the ion yields of 14N+ and 14N16O−, as well as the background intensity of …
- Regier, Margo Regier, Hervig, Richard L, Roggensack, Kurt, et al.
- Created Date
An exhaustive parameter study involving 133 dynamic crystallization experiments was conducted, to investigate the validity of the planetary embryo bow shock model by testing whether the cooling rates predicted by this model are consistent with the most dominant chondrule texture, porphyritic. Results show that using coarse-grained precursors and heating durations ≤ 5 minutes at peak temperature, porphyritic textures can be reproduced at cooling rates ≤ 600 K/hr, rates consistent with planetary embryo bow shocks. Porphyritic textures were found to be commonly associated with skeletal growth, which compares favorably to features in natural chondrules from Queen Alexandra Range 97008 analyzed, which …
- Perez, Alexandra Marie, Desch, Steven J, Till, Christy B, et al.
- Created Date
Explosive mafic (basaltic) volcanism is not easily explained by current eruption models, which predict low energy eruptions from low viscosity magma due to decoupling of volatiles (gases). Sunset Crater volcano provides an example of an alkali basalt magma that produced a highly explosive sub-Plinian eruption. I investigate the possible role of magmatic volatiles in the Sunset Crater eruption through study of natural samples of trapped volatiles (melt inclusions) and experiments on mixed-volatile (H2O-CO2) solubility in alkali-rich mafic magmas. I conducted volatile-saturated experiments in six mafic magma compositions at pressures between 400 MPa and 600 MPa to investigate the influence of …
- Allison, Chelsea M, Clarke, Amanda B, Hervig, Richard L, et al.
- Created Date
Remote sensing in visible to near-infrared wavelengths is an important tool for identifying and understanding compositional differences on planetary surfaces. Electronic transitions produce broad absorption bands that are often due to the presence of iron cations in crystalline mineral structures or amorphous phases. Mars’ iron-rich and variably oxidized surface provides an ideal environment for detecting spectral variations that can be related to differences in surface dust cover or the composition of the underlying bedrock. Several imaging cameras sent to Mars include the capability to selectively filter incoming light to discriminate between surface materials. At the coarse spatial resolution provided by …
- Wellington, Danika, Bell III, James F, Christensen, Philip R, et al.
- Created Date