Fixed-slope P$ rm sb{s}$-$ mu sb{ rm H2O}$ diagrams have been generated for the pseudoternary systems $ rm SiO sb2$-$ rm Na sb2 ZrO sb3$-$ rm H sb2O$ and $ rm SiO sb2$-$ rm CaZrO sb3$-$ rm H sb2O$ as first approximations to P-T phase relations for the Na- and Ca-zirconosilicates, respectively. Two possible topologies were determined for each pseudoternary based on an interchange of stable and metastable invariant points. Although for the $ rm SiO sb2$-$ rm Na sb2 ZrO sb3$-$ rm H sb2O$ system the correct topology cannot yet be resolved, owing to a lack of constraints from experimental and field observations, chemographic analysis reveals that the critical observation would be either the coexistence or incompatibility of the divariant mineral assemblage: elpidite + parakeldyshite. / The observed replacement of armstrongite by gittinsite + quartz in the Strange Lake peralkaline complex, Canada, suggests that the preferred topology for the $ rm SiO sb2$-$ rm CaZrO sb3$-$ rm H sb2O$ system may be the one in which the calcium catapleiite-, quartz- and calciohilairite-absent invariant points are stable. / Synthesis experiments in the $ rm SiO sb2$-$ rm CaZrO sb3$-$ rm H sb2O$ system resulted in the formation of the compound $ rm{Ca sb2 ZrSi sb4 O sb{12}}$ as well as zircon, baddeleyite, xonotlite and wollastonite under various conditions, but synthesis of naturally-occurring Ca-zirconosilicates remained elusive.
Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.56671 |
Date | January 1992 |
Creators | Marr, Robert A. (Robert Allen), 1965- |
Publisher | McGill University |
Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
Language | English |
Detected Language | English |
Type | Electronic Thesis or Dissertation |
Format | application/pdf |
Coverage | Master of Science (Department of Geological Sciences.) |
Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
Relation | alephsysno: 001315262, proquestno: AAIMM80448, Theses scanned by UMI/ProQuest. |
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