Hand Sample: Lapilli tuff containing pieces of pumice (HA-23) and trachyte obsidian (HA-22) ranging in size from 0.1cm to 1.5cm. Clasts are held together in light-colored ash. Sample surface crumbles when handled. Lapilli describes the size of the clasts, indicating a range in diameter of approx. 2 to 64mm.
Thin Section: Groundmass is predominantly clasts of pumice and trachyte obsidian, which are composed of glass and plagioclase grains in a glass matrix material.
Is Part Of
Volcanic Phenomena Suite - The Hawaiian Islands of Hawaii and Oahu
Number of Thin Sections