Volcano List
About Alaska's Volcanoes Hazards from Alaska's Volcanoes
Map & Alphabetical List Interactive Map
Eruption Search Volcano Search
|
Text Description: Stratigraphic Unit No. 11b. Interpreted deposit type: tephra fall. Thickness: 5.5 cm (132 cm cumulative; unit broken into 7 subunits based on bedding characteristics). Grain size: coarse to medium ash bound by fine ash stringers. Bedding: massive unit bound by clay/silt stringers. Sorting: well sorted between stringers. Juvenile clast type: black-glassy (dense, scoria-like clasts). Remarks: representative sample. Munsell color-wet: 10YR 2/2. Munsell color-dry: 10YR 4/2. Grain shape: angular-subround. Age: >3930+/-40 yr. B.P. References:  Characterization and discrimination of Holocene tephra-fall deposits, Mount Spurr volcano, Alaska |
This website is supported by the U.S. Geological Survey under Cooperative Agreement Grant G19AC00060 and G19AC00171.
Mention of trade names or commercial products does not constitute their endorsement by the U.S. Geological Survey.
Operations
Response
Staff
Fields of Study
Geology
Color Code Definitions
Webcams
Webicorders
RSAM
Great Sitkin
Cleveland
Glossary
Recent Images
Browse Images
