Geologic Publications for Mount Rainier

Identifying influences on glacial meltwater hydrochemistry using laboratory simulations of subglacial chemical erosion

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Author(s): Victoria Benson, Claire Todd

Category: POSTER
Document Type: Poster #158-1
Publisher: Geological Society of America Abstracts with Programs
Published Year: 2017
Volume: 49
Number: 6
Pages:
DOI Identifier: 10.1130/abs/2017AM-307707
ISBN Identifier:
Keywords:

Abstract:
Nisqually Glacier is a six-kilometer-long valley glacier on the southern flank of Mount Rainier, Washington. Analysis of Nisqually Glacier meltwater consistently yields low concentrations of sulfate and chloride ions. This goal of this study is to determine the influence of subglacial chemical erosion of bedrock on meltwater hydrochemistry. Hand samples representing bedrock near Nisqually Glacier were crushed to a rock flour, and suspended in deionized water and snowmelt for forty-eight hours in a cold room. The hand samples were identified as andesite and diorite through analysis of thin sections. Sediment mixed with snowmelt leached up to 0.53 ± 0.74 mg/L of sulfate and 0.45 ± 0.03 mg/L of chloride.These concentrations are a small fraction of concentrations measured in Nisqually Glacier meltwater. High uncertainty and the lack of a relationship between sediment concentration and leached constituents warrant further experimental trials. Despite high uncertainty, our results suggest that Nisqually Glacier meltwater could be influenced by Mount Rainier’s hydrothermal system. Future experiments will test this hypothesis.

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In Text Citation:
Benson and Todd (2017) or (Benson and Todd, 2017)

References Citation:
Benson, V. and C. Todd, 2017, Identifying influences on glacial meltwater hydrochemistry using laboratory simulations of subglacial chemical erosion: Poster #158-1, Geological Society of America Abstracts with Programs, Vol. 49, No. 6, doi: 10.1130/abs/2017AM-307707.