Rights statement: This is the author’s version of a work that was accepted for publication in Lithos. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Lithos, 328-329, 2019 DOI: 10.1016/j.lithos.2019.01.017
Accepted author manuscript, 7.93 MB, PDF document
Available under license: CC BY-NC-ND
Final published version
Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
}
TY - JOUR
T1 - The Gold Flat Tuff, Nevada
T2 - Insights into the evolution of peralkaline silicic magmas
AU - MacDonald, Raymond
AU - Bagiński, Bogusław
AU - Belkin, Harvey
AU - White, John
AU - Noble, D.C.
N1 - This is the author’s version of a work that was accepted for publication in Lithos. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Lithos, 328-329, 2019 DOI: 10.1016/j.lithos.2019.01.017
PY - 2019/3/1
Y1 - 2019/3/1
N2 - The Gold Flat Tuff is the youngest (9.15 Ma) ash-flow sheet erupted from the Black Mountain Volcanic Centre, southwest Nevada, USA. This paper explores some aspects of the very complex nature of the tuff's magmatic plumbing system. The main body of the deposit is a mixed magma product, comprising pantelleritic and comenditic melts derived from independently evolving reservoirs, and antecrysts and enclaves derived from a range of basic to intermediate sources. Metre-scale cognate xenoliths point to the presence of alkali feldspar accumulation zones. The pantellerite contains phenocrysts of fluorite and chevkinite-(Ce). The inferred intermediate magma component contains perrierite-(Ce) phenocrysts. The pantellerite has unusually high contents of F (≤2.2 wt%), F + Cl (≤2.9 wt%) and ZrO 2 (≤1.04 wt%). The high halogen contents may have influenced the evolution of the strongly peralkaline magma. The crystallization conditions are poorly constrained but those for the pantelleritic magma may have been close to water-saturation (>4 wt% melt water) at temperatures ~740 °C and fO 2 around FMQ.
AB - The Gold Flat Tuff is the youngest (9.15 Ma) ash-flow sheet erupted from the Black Mountain Volcanic Centre, southwest Nevada, USA. This paper explores some aspects of the very complex nature of the tuff's magmatic plumbing system. The main body of the deposit is a mixed magma product, comprising pantelleritic and comenditic melts derived from independently evolving reservoirs, and antecrysts and enclaves derived from a range of basic to intermediate sources. Metre-scale cognate xenoliths point to the presence of alkali feldspar accumulation zones. The pantellerite contains phenocrysts of fluorite and chevkinite-(Ce). The inferred intermediate magma component contains perrierite-(Ce) phenocrysts. The pantellerite has unusually high contents of F (≤2.2 wt%), F + Cl (≤2.9 wt%) and ZrO 2 (≤1.04 wt%). The high halogen contents may have influenced the evolution of the strongly peralkaline magma. The crystallization conditions are poorly constrained but those for the pantelleritic magma may have been close to water-saturation (>4 wt% melt water) at temperatures ~740 °C and fO 2 around FMQ.
KW - Chevkinite-(Ce) phenocrysts
KW - Fluorite and
KW - Gold Flat Tuff
KW - Magma mixing
KW - Nevada
KW - Peralkaline rhyolites
KW - Topic:
KW - ash flow
KW - fluorite
KW - magma
KW - magmatism
KW - peralkaline rock
KW - phenocryst
KW - rhyolite
KW - United States
U2 - 10.1016/j.lithos.2019.01.017
DO - 10.1016/j.lithos.2019.01.017
M3 - Journal article
VL - 328-329
SP - 1
EP - 13
JO - Lithos
JF - Lithos
SN - 0024-4937
ER -