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Title: Upper mantle shear wave velocity structure beneath northern Victoria Land, Antarctica: Volcanism and uplift in the northern Transantarctic Mountains

Authors:
; ; ; ; ; ORCiD logo
Publication Date:
Sponsoring Org.:
USDOE National Nuclear Security Administration (NNSA)
OSTI Identifier:
1323956
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Earth and Planetary Science Letters
Additional Journal Information:
Journal Volume: 449; Journal Issue: C; Related Information: CHORUS Timestamp: 2017-10-06 15:00:30; Journal ID: ISSN 0012-821X
Publisher:
Elsevier
Country of Publication:
Netherlands
Language:
English

Citation Formats

Graw, Jordan H., Adams, Aubreya N., Hansen, Samantha E., Wiens, Douglas A., Hackworth, Lauren, and Park, Yongcheol. Upper mantle shear wave velocity structure beneath northern Victoria Land, Antarctica: Volcanism and uplift in the northern Transantarctic Mountains. Netherlands: N. p., 2016. Web. doi:10.1016/j.epsl.2016.05.026.
Graw, Jordan H., Adams, Aubreya N., Hansen, Samantha E., Wiens, Douglas A., Hackworth, Lauren, & Park, Yongcheol. Upper mantle shear wave velocity structure beneath northern Victoria Land, Antarctica: Volcanism and uplift in the northern Transantarctic Mountains. Netherlands. doi:10.1016/j.epsl.2016.05.026.
Graw, Jordan H., Adams, Aubreya N., Hansen, Samantha E., Wiens, Douglas A., Hackworth, Lauren, and Park, Yongcheol. 2016. "Upper mantle shear wave velocity structure beneath northern Victoria Land, Antarctica: Volcanism and uplift in the northern Transantarctic Mountains". Netherlands. doi:10.1016/j.epsl.2016.05.026.
@article{osti_1323956,
title = {Upper mantle shear wave velocity structure beneath northern Victoria Land, Antarctica: Volcanism and uplift in the northern Transantarctic Mountains},
author = {Graw, Jordan H. and Adams, Aubreya N. and Hansen, Samantha E. and Wiens, Douglas A. and Hackworth, Lauren and Park, Yongcheol},
abstractNote = {},
doi = {10.1016/j.epsl.2016.05.026},
journal = {Earth and Planetary Science Letters},
number = C,
volume = 449,
place = {Netherlands},
year = 2016,
month = 9
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1016/j.epsl.2016.05.026

Citation Metrics:
Cited by: 2works
Citation information provided by
Web of Science

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  • Silicate and glassy spherules of probably extraterrestrial origin have been discovered in glacial till from localities in the Beardmore glacier region, Transantarctic Mountains, Antarctica. These spherules are similar in structure, appearance, and composition to spherules found in deep-sea sediments and in Greenland. Most spherules have a shiny and smooth dark surface, while some show a characteristic brickwork pattern composed of intergrown olivine crystals and magnetite dendrites. Several spherules have been sectioned after trace element analysis by INAA. The interiors of the spherules contain olivine crystals of varying size (predominantly of forsteritic composition) set in a glassy Fe-rich and Mg-poor matrix.more » The matrix contains very fine-grained dendritic magnetite crystals and rare accessory wustite. SEM and microprobe studies show that most of the spherules have not experienced significant weathering. Trace element analyses for individual particles confirm the extraterrestrial nature of the spherules. They have undifferentiated chondritic rare earth element (REE) patterns and are enriched in Ir and other siderophile elements (with Ir contents between 10 and > 1,000 ppb). Some spherules have experienced loss of volatile elements and some differentiation of siderophile elements (e.g., Ni). The Antarctic spherules--which might be micrometeorites that melted during passage through the atmosphere, or ablation spherules--are a significant addition to the collection of extraterrestrial microparticles. Of key importance is their high abundance in the sediment and the fact that they have been concentrated by glacial action.« less