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Text Description: GI tephra occurs at site B approximately 8 m above the newly identified Charley River tephra that is also present at site A. GI tephra consists mostly of colorless, bubble-wall glass shards with some brown glass and pumice fragments. Mineral grains, which are sparse, include feldspar, apatite, and orthopyroxene. The composition reported here is the average of two samples from the Chester Bluff area: UT1666 and UT1743. Two populations of glass identified by Froese et al. (2003), and a single point with a different composition. References: ![]() |
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