A tale of two minerals : using isotopes and trace elements of tourmaline and zircon to constrain fluid and magma sources in diverse settings
Abstract/Contents
- Abstract
- Accessory minerals such as tourmaline and zircon typically comprise a small fraction of a given rock, yet they offer powerful insights into its history that far outweigh their size and abundance. These insights stem from their ability to incorporate a suite of elements and their isotopes that have remarkable petrogenetic utility and retain such information across a range of geologic environments. In this dissertation, I use isotopic and trace element analysis of tourmaline and zircon to constrain the sources of fluids and magmas and understand their evolution in diverse settings. Chapter 1 of this dissertation investigates the probable sources of boron-bearing fluids that gave rise to the presence of hydrothermal tourmaline within a granitic intrusion, its metamorphosed aureole, and its unaltered wallrocks. By examining tourmaline recovered from each locality, I demonstrate via boron isotopic constraints that the ultimate source of boron is the subduction-accretionary rocks of the Franciscan Complex, although its incorporation into the intrusive-metamorphic system is accomplished in various ways. Chapters 2 and 3 of this dissertation involve two related studies that utilize zircon both as a geochronometer and as a geochemical proxy to determine magmatic crystallization ages and to infer the tectonic environments within which a magma system evolved. In Chapter 2, I demonstrate that metamorphosed plutonic and volcaniclastic sedimentary "exotic" blocks within the Yuli Belt mélange of Taiwan represent accreted and deeply-buried fragments of an early--middle Miocene magmatic arc that is a likely precursor to the modern Luzon Arc. This contrasts markedly with the current paradigm that these exotic blocks represent fragments of the South China Sea oceanic crust. In Chapter 3, I analyzed zircons from the late Miocene-- Pleistocene Luzon Arc accreted onto the Taiwan orogen to assess the arc magmatic response to the transition from intra-oceanic subduction to arc-continent collisional regime.
Description
| Type of resource | text |
|---|---|
| Form | electronic resource; remote; computer; online resource |
| Extent | 1 online resource. |
| Place | California |
| Place | [Stanford, California] |
| Publisher | [Stanford University] |
| Copyright date | 2022; ©2022 |
| Publication date | 2022; 2022 |
| Issuance | monographic |
| Language | English |
Creators/Contributors
| Author | Marcaida, Mary Mae |
|---|---|
| Degree supervisor | Grove, Marty, 1958- |
| Thesis advisor | Grove, Marty, 1958- |
| Thesis advisor | Bird, Dennis K |
| Thesis advisor | Dorsey, Rebecca J |
| Thesis advisor | Pamukcu, Ayla Susan |
| Degree committee member | Bird, Dennis K |
| Degree committee member | Dorsey, Rebecca J |
| Degree committee member | Pamukcu, Ayla Susan |
| Associated with | Stanford University, Department of Geology |
Subjects
| Genre | Theses |
|---|---|
| Genre | Text |
Bibliographic information
| Statement of responsibility | Mae Marcaida. |
|---|---|
| Note | Submitted to the Department of Geology. |
| Thesis | Thesis Ph.D. Stanford University 2022. |
| Location | https://purl.stanford.edu/wv984xb3566 |
Access conditions
- Copyright
- © 2022 by Mary Mae Marcaida
- License
- This work is licensed under a Creative Commons Attribution Non Commercial 3.0 Unported license (CC BY-NC).
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