Stratigraphic Unit No. 8. Interpreted deposit type: tephra fall - possibly reworked. Thickness: 70 cm. Grain size: coarse ash base grading up to medium to fine ash with a horizon of 2-4 mm rounded ash pods. Bedding: normally graded. Sorting: poorly sorted. Juvenile clast type: black (dense, scoria-like clasts). Remarks: coarse ash base round pods near top of unit 8. Munsell color-wet: 10YR 4/2. Munsell color-dry: 10YR 6/2. Grain shape: subround-angular. Age: >3930+/- 40 yr. B.P.
Characterization and discrimination of Holocene tephra-fall deposits, Mount Spurr volcano, Alaska
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