Welcome!
Hi, I’m Crystal Luna. I’m currently a graduate student at the University of Wyoming working under Dr. Michael Cheadle and Dr. Barbara John.
I'm a native Texan and served in the Army National Guard for 8 years as an Intelligence Analyst. I worked as a mathematics supplemental instructor/instructional assistant for 5 years at Tarrant County College. I also worked for Shimadzu Institute in their Environmental, Forensics and Material Science Lab for 2 years. Additionally, I've done GIS work as a Telecom Engineer and during my time as an Intelligence Analyst.
Current Research
Studying beautiful rocks from Pito Deep, a site at the bottom of Pacific Ocean, near Easter Island to understand how ocean crust forms. Detailed continental style mapping of crustal sections at Pito Deep was performed using a combination of high-resolution outcrop mapping by AUV and oriented sampling by ROV.
Analyzing the geochemistry of gabbroic rock samples taken in situ at Pito Deep, a tectonic window which exposes lavas, dikes, and >1 km of gabbro. Investigating the formation of fast-spread ocean crust with the aim of understanding what model best reflects their formation as well as working to improve the representative stratigraphy for fast-spread ocean crust.
Pito Deep is located near the edge of the Easter Microplate, a small tectonic plate rotation allowing fault blocks to expose lower ocean crust. (Cheadle, personal communication, 2020).
The gabbro glacier and sheeted sill models are the current end member models describing the processes leading to the formation of fast-spread ocean crust.
The sheeted sill model proposes melt emplaced at various depths into multiple sills.
The gabbro glacier flow model proposes constant melt migration into an axial melt lens (AML) with accompanying flow of crystals downward and outward
Schematic diagram highlighting differences between end-member models for formation of fast-spread ocean crust (by Gess, after Coogan, 2007).
My research project focuses on the element analysis of plagioclase, olivine, and pyroxene. Chemical compositions are indicators of the type of melt the minerals crystallized from (e.g. primitive vs evolved) which suggest processes leading to their formation (e.g. gabbro glacier flow vs sheeted sill). Specifically, I will be looking at major element analyses of anorthite content (An content) in plagioclase, forsterite content (Fo content) in olivine as well as Mg# (Mg/(Fe+Mg)) in clinopyroxene. Also, some minor element analyses of Fe2O3 and NiO in plagioclase, TiO2 in clinopyroxene, and Cr2O3 in olivine will be evaluated. More primitive melts (e.g. high Mg#, An content, and Fo content) may suggest a gabbro glacier flow type of model while "sawtooth" trends in primitive to evolved compositions up section may reflect sill emplacement as in the sheeted sill model. Although, there's also the possibility that a hybrid or other model may be necessary to describe results from analyses.
Significance
Ocean crust forms 60% of the Earth’s surface, 35% of which formed at fast spreading ridges, although we still do not fully understand how fast-spread crust forms. This work can provide answers to the long-unanswered questions about how this crust forms.
Crystal Luna
1000 University St.
Department of Geology and Geophysics
Email:
cluna2@uwyo.edu
