The Bend pumice and Tumalo tuff are products of a plinian eruption which occurred sometime between 0.89 and 2.6 m.y. The Bend pumice is a poorly consolidated, air-fall vitric lapilli tuff, which overlies a zone of reworked tephra. Perlitic obsidian in the reworked zone probably represents the remains of a...
The Bend pumice and Tumalo tuff are products of a plinian eruption which occurred sometime between 0.89 and 2.6 m.y. The Bend pumice is a poorly consolidated, air-fall vitric lapilli tuff, which overlies a zone of reworked tephra. Perlitic obsidian in the reworked zone probably represents the remains of a...