Ultra-slow aging dynamics of glass and its application to geological dating.

Abstract

The ultra-slow relaxation dynamics of glasses at ambient temperature provide a promising alternative for dating glasses with extremely low isotopic content that cannot be dated using traditional radiometric methods. However, these ultra-slow, nonlinear aging dynamics remain poorly understood due to the lack of accurate theoretical models and long-term experimental validation. Existing equilibrium-based dynamics models substantially overestimate relaxation times at temperatures far below the glass transition temperature, making it difficult to model and quantify non-equilibrium aging over geological timescales. We address this challenge by formulating an empirical equation that quantifies the non-equilibrium effective relaxation time (τ_eff) for various glasses, including metallic glasses, organic amber, and lunar glasses. Our findings demonstrate a universal nonlinear aging dynamics governed by a single τ_eff, which follows a robust empirical relation parameterized by aging temperature and material-specific fragility. Employing this equation, we propose a universal glass kinetics dating method, conceptually analogous to radioactive decay, where τ_eff serves as a material-specific decay constant. This approach enables dating of glassy materials over timescales spanning decades to billions of years. This work bridges a fundamental gap in glass aging theory and establishes a practical framework for dating geological and planetary glasses.