Sample: Jensen_Palisades-11_average
| Sample ID: |
Jensen_Palisades-11_average [1] |
| Station ID: |
Jensen_Palisades_East |
| AT Num: |
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| Volcano: |
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| Possible source: |
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| Eruption: |
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| Collector: |
Jensen, B. J. L. |
| Date sampled: |
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| Sample type 1: |
Tephra Fall |
| Color: |
gray |
| Final unit: |
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| Text Description: |
The composition reported here is the average of analyses of two samples: UA1126 and UA2082. This bed was found within inorganic loess 50-75 cm below OCt at two measured sections at Site B . It is a diffuse, discontinuous, gray tephra with a maximum thickness of 0.3 cm. Its stratigraphic position relative to SC-F is uncertain since they have not been found in the same section. However, Jensen and others (2013) tentatively place SC-F stratigraphically below P11 because at all sites where it is found, P11 is within 1 m of OCt, while SC-F is generally 2-6 m below OCt (Figs. 2 and 3; Jensen and others, 2013). Glass morphology is distinct, consisting almost entirely of blocky, thick-walled pumice, often elongate, with common microcryts and small, evenly distributed vesicles. Phenocrysts are rare and are dominantly plagioclase with minor amphibole. |
| Sample Location: |
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References Cited
Jensen, B.J.L., Reyes, A.V., Froese, D.G., and Stone, D.B., 2013, The Palisades is a key reference site for the middle Pleistocene of eastern Beringia: new evidence from paleomagnetics and regional tephrostratigraphy: Quaternary Science Reviews, v. 63, p. 91-108, http://dx.doi.org/10.1016/j.quascirev.2012.11.035