gsminmag Mineralogical Magazine Mineralogical Magazine 0026-461X Mineralogical Society 10.1180/minmag.1964.033.266.04 Rhythmic Amphibole Overgrowths in Appinites Associated with Explosion-Breccias in Argyll Bowes D. R. Kinloch E. D. Department of Geology, The University, Glasgow, W. 2 Wright A. E. Department of Geology, The University, Birmingham, 15 9 1964 33 266 963 973 Copyright © 1964, The Mineralogical Society 1964 Summary

Tremolite and actinolite form rhythmic overgrowths over hornblende in appinites associated with pipes of explosion-breccia and represent growth under alternating physical conditions arising from increase of gas pressure and its explosive release. The number of overgrowths present in each appinite mass is related to the number of explosions required to breach the particular structural trap that hindered the upward movement of the volatiles.