Thermal influences on spontaneous rock dome exfoliation

Nature Communications
By: , and 

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Abstract

Rock domes, with their onion-skin layers of exfoliation sheets, are among the most captivating landforms on Earth. Long recognized as integral in shaping domes, the exact mechanism(s) by which exfoliation occurs remains enigmatic, mainly due to the lack of direct observations of natural events. In August 2014, during the hottest days of summer, a granitic dome in California, USA, spontaneously exfoliated; witnesses observed extensive cracking, including a ~8000 kg sheet popping into the air. Subsequent exfoliation episodes during the following two summers were recorded by instrumentation that captured—for the first time—exfoliation deformation and stress conditions. Here we show that thermal cycling and cumulative dome surface heating can induce subcritical cracking that culminates in seemingly spontaneous exfoliation. Our results indicate that thermal stresses—largely discounted in dome formation literature—can play a key role in triggering exfoliation and therefore may be an important control for shaping domes worldwide.

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Thermal influences on spontaneous rock dome exfoliation
Series title Nature Communications
DOI 10.1038/s41467-017-02728-1
Volume 9
Year Published 2018
Language English
Publisher Nature
Contributing office(s) Geology, Minerals, Energy, and Geophysics Science Center
Description Article 762; 12 p.
First page 1
Last page 12