Work

Fast or slow: An evaluation of Ti-in-quartz diffusion coefficients through comparisons of quartz and plagioclase diffusion times

Year: 2025

Type: article

Abstract: Diffusion geochronometry using Ti-in-quartz has become a valuable method in understanding the evolution of silicic magmas. However, four different options for Ti diffusivity (DTi) currently exist, spanning three orders of magnitude, resulting in substantially different estimated times and interpretations. We present Ti-in-quartz diffusion times for the Cerro Galán Ignimbrite using the Cherniak et al. [2007] (10.1016/j.chemgeo.2006.09.001), Audétat et al. [2021] (10.1130/g48785.1), Audétat et al. [2023] (10.1038/s41467-023-39912-5), and Jollands et al. [2020] (10.1130/g47238.1) DTi value and (1) compare these against plagioclase diffusion times derived from the same samples, (2) consider evidence for Ti diffusion in quartz under relevant magmatic timescales, and (3) compute derived quartz growth rates for crystals from the Cerro Galán Ignimbrite. On all accounts, we find that the Cherniak et al. [2007] diffusion coefficient yields diffusion times that agree much better with independent evidence than those derived using slower DTi values [Jollands et al. 2020; Audétat et al. 2021; 2023].

Source: Volcanica

DOI: 10.30909/vol/rjfq2443

Authors: Sophia Y. Wang, Guilherme A. R. Gualda, Jordan Lubbers, Adam J. R. Kent

Institutions: Oregon State University, Vanderbilt University, United States Geological Survey, Alaska Volcano Observatory

Language: English

Topic: Geological and Geochemical Analysis

Subfield: Geophysics

Field: Earth and Planetary Sciences

Domain: Physical Sciences

Open Access status: diamond

Funder: National Science Foundation

Awards: Collaborative Research: Synthesizing arc-scale geochemical, petrologic, and geophysical datasets to investigate causes of volcanic diversity in the Cascade Arc, Collaborative Research: The Tumalo Volcanic Center - Probing the Origin of Explosive Pleistocene Silicic Volcanism in Central Oregon