Application of the Very Broadband Rheology Calculator to Inference of Transient Creep Data and Extrapolation to Upper Mantle Structure
Abstract
The Very Broadband Rheology calculator (VBRc) is an open-source library for forward calculating mechanical properties across the entire range of geophysical time scales, from convection to seismic wave propagation. It is designed for two parallel purposes: (1) inference of thermodynamic state and mechanical behavior of the earth, as predicted by extrapolation of laboratory-derived constitutive models, and (2) analysis of experimental data for development of constitutive models within a common tool, towards improving transparency of inter-lab comparison. The aim is to both improve the understanding of discrepancies among laboratory data and models and increase the uptake of laboratory constitutive models by communities that need them for field data analysis, interpretation and prediction. However, upon the VBRc's initial release in late 2019, the mechanical property modules were limited to elastic, viscous and linear anelastic constitutive models for olivine, applicable to upper mantle conditions, and use cases focused on applications to seismic wave speed and attenuation measurements. In this presentation, we will demonstrate how the framework can be used for probabilistic inference of parameters for constitutive models from lab data, including time dependence (by two methods: a frequency-dependence at constant state, or quasistatic evolution of state variables). We will present comparisons between constitutive models in the context of our ``complex viscosity'' framework for lithosphere-asthenosphere structure, with new applications to glacial isostatic adjustment responses. We will also address issues of self-consistency for non-linear dislocation processes across the spectrum of time scales relevant for geophysical observations.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2020
- Bibcode:
- 2020AGUFMMR0220020H
- Keywords:
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- 5104 Fracture and flow;
- PHYSICAL PROPERTIES OF ROCKS;
- 5120 Plasticity;
- diffusion;
- and creep;
- PHYSICAL PROPERTIES OF ROCKS;
- 5144 Wave attenuation;
- PHYSICAL PROPERTIES OF ROCKS;
- 8032 Rheology: general;
- STRUCTURAL GEOLOGY