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Akutan AKSD Augustine - Homer Augustine - island Augustine - Lagoon Augustine - low light Cleveland CLCO Gareloi Great Sitkin Great Sitkin -GSIG Iliamna Iliamna IVE Kanaga Kanaga - KIMD Makushin Okmok OKIF Pavlof - BLHA Pavlof - DOL Peulik Redoubt - CI Redoubt - DFR Redoubt - Hut Shishaldin Shishaldin-WTUG SpurrCKT Tanaga Wrangell
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Text Description: Juvenile clast-rich layer. The basal J1 layer is the thickest layer and is comprised entirely of inflated fresh scoria that is commonly black. Scoria sags, reverse grading, and bomb horizons exist in J1 at the sites closest to the caldera, 6-8 km from the rim. References:  Physical volcanology of a sub-plinian and phreatomagmatic eruption at Okmok Volcano, Alaska: implications for explosive mafic volcanism |
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