Eroded ash flow tuffApril 30, 2017/in /by Marli Miller differential erosion, volcanic, pyroclastic, weathering https://geologypics.com/wp-content/uploads/2017/04/geologic-time-pics-logo-300x115.png 0 0 Marli Miller https://geologypics.com/wp-content/uploads/2017/04/geologic-time-pics-logo-300x115.png Marli Miller2017-04-30 20:09:182017-09-24 16:36:59Eroded ash flow tuff