Sample: Jensen_Palisades_East_PAL_tephra_average
| Sample ID: |
Jensen_Palisades_East_PAL_tephra_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: |
pink |
| Final unit: |
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| Text Description: |
The composition reported here is the average of analyses of six samples: UA1199, UA1200, UA1201, UA1305, UA1306, and UA1307. Strikingly pink tephra that is one of the most prominent tephra beds found at the Palisades. Collected at all logged sites across Palisades East, except Site F, and as two opportunistically collected samples while tracing the tephra laterally across the exposure. It was generally found below a peat, although organic-rich silt and peat deposits were also found below it at several sites (Fig.2; Jensen and others, 2013). Site D1, which contains a primary bed of PAL complete with root casts and laminations, appears to be the least disturbed measured section (Fig. 4A; Jensen and others, 2013). There, PAL is overlain by a 1 m thick peat bed, while organic-rich silt with large woody macrofossils is present w2 m below the tephra (Figs. 2 and 4B; Jensen and others, 2013). Primary beds of PAL are 2-5 cm thick, but locally the bed is reworked to thicknesses of 10-20 cm. Glass morphology is diverse, and includes tricuspate and bubble-walled shards, and blocky to frothy pumice. |
| 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