SEDIS - Publications
White, Russell J. et al. (2011): Importance of volcanic glass alteration to sediment stabilization; offshore Japan
ODP 190 1173
ODP 196 1173
ODP 190 1174
White, Russell J.
New Mexico Institute of Mining and Technology, Department of Earth and Environmental Science, Socorro, NM, United States
Spinelli, Glenn A.
New Mexico Bureau of Geology and Mineral Resources, United States
Mozley, Peter S.
Dunbar, Nelia W.
Importance of volcanic glass alteration to sediment stabilization; offshore Japan
Wiley-Blackwell, Oxford, United Kingdom
A minor amount (ca 1 wt%) of amorphous silica cement sourced from volcanic glass inhibits consolidation of hemipelagic sediment approaching the Nankai Trough subduction zone throughout the Shikoku Basin. The distribution and nature of the cement were examined via secondary and backscattered electron imaging. The amorphous silica occurs as altered material in contact with volcanic glass, coating grains (including grain contacts) and filling pores. Based on chemical and petrographic evidence, the cement is probably sourced from volcanic glass; this is in contrast to a previous suggestion that this silica cement is sourced dominantly from biogenic silica. Amorphous silica sourced from disseminated volcanic glass shards has the ability to form a thin coating on clay-dominated sediment throughout the Shikoku Basin. Measured amorphous silica content in hemipelagic sediments suggests that the cementing process is active throughout the Shikoku Basin (at sites separated by >500 km). The cementation process may occur in other locations where sediment containing hydrated disseminated volcanic glass is buried sufficiently for heat to facilitate alteration (i.e. Central America, Cascadia and the Gulf of Alaska). Abstract Copyright (2010), International Association of Sedimentologists.
Sedimentary petrology; alteration; cementation; clastic sediments; clay; diagenesis; glasses; hemipelagic environment; igneous rocks; Leg 190; marine environment; Nankai Trough; North Pacific; Northwest Pacific; Ocean Drilling Program; ODP Site 1173; ODP Site 1174; Pacific Ocean; sediments; Shikoku Basin; volcanic glass; volcanic rocks; West Pacific;
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