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Sample: UT497

Sample ID: UT497 [1] [2] [3] [4] [5] [6] [7]
Station ID: Gold_Hill_II
AT Num:
Volcano:
Possible source:
Eruption:
Collector: Preece, S. J.
Date sampled:
Sample type 1: Tephra Fall
Color: pink-grey
Final unit:
Text Description: Semi-lithified tephra located in the basal part of the Gold Hill Loess, 11 m above the Cripple Gravel. It has been deformed by solifluction into pods, up to 5 cm thick and 38 cm long, that are spread out vertically over a 20-25 cm interval and interbedded with massive, grey (2.5Y6/3) and oxidized (2.5Y6/4) silt. All contacts with the surrounding loess are sharp in most places and wispy in a few. There is often a darker pink rim, a few mm to less than a mm thick, along the silt-tephra contact of the pods. In some places, the tephra has been oxidized and is rusty along the silt-tephra contact. The larger pods are sometimes separated into smaller pods by wisps or mm thick silt layers, and some of the pods have very convoluted outlines while others are more regular ovals. It can be traced continuously from stations Gold_Hill_II to Gold_Hill_IV. Sample contains aggregates of fine-grained, colourless and brown glass shards poorly cemented by silica. Highly vesicular pumice is common with elongate vesicles, however, poorly vesicular pumice and bubblewall glass shards also common. Mineral component includes feldspar and FeTi oxides with accessory amounts of clinopyroxene, orthopyroxene, hornblende, and apatite.
Sample Location:

References Cited

[1] Tephrostratigraphy of the late Cenozoic Gold Hill loess, Fairbanks area, Alaska, 1991

Preece, S. J., 1991, Tephrostratigraphy of the late Cenozoic Gold Hill loess, Fairbanks area, Alaska: University of Toronto (Canada) M.S. thesis, 186 p.

[2] Tephrochronology of late Cenozoic loess at Fairbanks, central Alaska, 1999

Preece, S. J., Westgate, J. A., Stemper, B. A., and Pewe, T. L., 1999, Tephrochronology of late Cenozoic loess at Fairbanks, central Alaska: Geological Society of America Bulletin, v. 111, n. 1, p. 71-90.

[3] The Dawson Cut Forest Bed in the Fairbanks area, Alaska, is about two million years old, 2003

Westgate, J. A., Preece, S. J., and Pewe, T. L., 2003, The Dawson Cut Forest Bed in the Fairbanks area, Alaska, is about two million years old: in Westgate, J. A., (ed.), Special issue dedicated to Troy Pewe, Quaternary Research, v. 60, n. 1, p. 2-8.

[4] Late Pliocene Dawson Cut forest bed and new tephrochronological findings in the Gold Hill Loess, east-central Alaska, 2009

Pewe, T.L., Westgate, J.A., Preece, S.J., Brown, P.M., and Leavitt, S.W., 2009, Late Pliocene Dawson Cut forest bed and new tephrochronological findings in the Gold Hill Loess, east-central Alaska: Geological Society of America Bulletin, v. 121, n. 1-2, p. 294-320, doi: 10.1130/B26323.1 .

[5] The Palisades is a key reference site for the middle Pleistocene of eastern Beringia: new evidence from paleomagnetics and regional tephrostratigraphy, 2013

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

[6] Update on the late Cenozoic tephrochronology of the Gold Hill loess at Fairbanks, Alaska, and correlation with the Klondike goldfields in the Yukon, 2000

Westgate, J.A., Preece, S.J., Sandhu, A.S., and Froese, D.G., 2000, Update on the late Cenozoic tephrochronology of the Gold Hill loess at Fairbanks, Alaska, and correlation with the Klondike goldfields in the Yukon [abs.], in Troy Pewe Memorial Workshop: Paleoclimates and Paleoenvironments in Eastern Beringia and the Bering Land Bridge, Fairbanks, Alaska, August 21-24, 2000, Alaska Quaternary Center, University of Alaska Fairbanks.

[7] A 3-my record of Pliocene-Pleistocene loess in interior Alaska, 1990

Westgate, J.A., Stemper, B.A., and Pewe, T.L., 1990, A 3-my record of Pliocene-Pleistocene loess in interior Alaska: Geology, v. 18, p. 858-861.