Stress and Strain during Shock Metamorphism

This is a Preprint and has not been peer reviewed. This is version 1 of this Preprint.

Downloads

Download Preprint

Authors

Auriol S. P. Rae , Michael H. Poelchau, Thomas Kenkmann

Abstract

Shock metamorphism is the process by which rocks, and the minerals within them, transform during the passage of a shock wave. Shock effects, such as shatter cones, are critical for the identification of impact structures and have commonly been used to infer mechanical and structural information on the cratering process. To make these inferences, the mechanics of shock wave behavior must be understood. Here, we use numerical simulations to demonstrate how stresses act during shock metamorphism across all regions of the target that experience solid-state shock metamorphism. Furthermore, our numerical simulations predict the strains that are produced as a consequence of those stresses. The results show that the magnitude and orientation of stress and strain during shock metamorphism are variable throughout the target, both spatially and temporally, even between rocks that experience the same peak shock pressure. The provenance of a sample relative to the point of impact and the timing/mechanism of the formation of a shock effect must both be considered when making structural interpretations. The stress and strain magnitudes and orientations as functions of time and location presented in this study provide the constraints that enable a greater understanding of the formation of a variety of shock deformation effects. We demonstrate this with a case study of shatter cones at the Gosses Bluff impact structure. We hope that our results can be used to guide geologists and petrologists in the interpretation of shock metamorphic effects.

DOI

https://doi.org/10.31223/X5HC8W

Subjects

Geology, Planetary Geology, Planetary Geophysics and Seismology, Tectonics and Structure

Keywords

Stress, Strain, Impact Cratering, Shock Metamorphism, Shatter Cones

Dates

Published: 2021-04-15 12:12

Last Updated: 2021-04-15 19:12

License

CC BY Attribution 4.0 International

Add a Comment

You must log in to post a comment.


Comments

There are no comments or no comments have been made public for this article.