Search results for "Interstitial water"

Vesiculated tuffs and associated features

1974

Vesiculated tuffs are tuffs that contain vesicles between the ash particles. Formation of the vesicles is the result of trapping of steam, the transporting agent of volcanic base surges, in wet, muddy or sticky ash deposited by the base surges. Vesiculated tuffs are described from various maars and tuff-rings in Europe (Iceland, France, Germany) and USA together with associated surface features such as: gravity flowage ripples, mud flow channels, current ripples, and current ridges. Other features described are: plastering of ash against obstacles and vesiculated accretionary lapilli, the latter containing vesicles in the outer layer. Vesiculated base surge deposits probably contained as mu…