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dc.contributor.authorZechmann, Jenna M.
dc.contributor.authorBooth, Adam D.
dc.contributor.authorTruffer, Martin
dc.contributor.authorGusmeroli, Alessio
dc.contributor.authorAmundson, Jason M.
dc.contributor.authorLarsen, Christopher S.
dc.date.accessioned2020-07-31T20:54:43Z
dc.date.available2020-07-31T20:54:43Z
dc.date.issued2018-09-20
dc.identifier.citationZechmann, J. M., Booth, A. D., Truffer, M., Gusmeroli, A., Amundson, J. M., & Larsen, C. F. (2018). Active seismic studies in valley glacier settings: Strategies and limitations. Journal of Glaciology, 64(247), 796–810. https://doi.org/10.1017/jog.2018.69en_US
dc.identifier.urihttp://hdl.handle.net/11122/11198
dc.descriptionSubglacial tills play an important role in glacier dynamics but are difficult to characterize in situ. Amplitude Variation with Angle (AVA) analysis of seismic reflection data can distinguish between stiff tills and deformable tills.en_US
dc.description.abstractSubglacial tills play an important role in glacier dynamics but are difficult to characterize in situ. Amplitude Variation with Angle (AVA) analysis of seismic reflection data can distinguish between stiff tills and deformable tills. However, AVA analysis in mountain glacier environments can be problem- atic: reflections can be obscured by Rayleigh wave energy scattered from crevasses, and complex basal topography can impede the location of reflection points in 2-D acquisitions. We use a forward model to produce challenging synthetic seismic records in order to test the efficacy of AVA in crevassed and geo- metrically complex environments. We find that we can distinguish subglacial till types in moderately cre- vassed environments, where ‘moderate’ depends on crevasse spacing and orientation. The forward model serves as a planning tool, as it can predict AVA success or failure based on characteristics of the study glacier. Applying lessons from the forward model, we perform AVA on a seismic dataset col- lected from Taku Glacier in Southeast Alaska in March 2016. Taku Glacier is a valley glacier thought to overlay thick sediment deposits. A near-offset polarity reversal confirms that the tills are deformable.en_US
dc.description.sponsorshipThe Taku 2016 survey was made possible by input and assist- ance from Thomas Hart (blaster), Aurora Roth, and Andy Aschwanden. IRIS PASSCAL provided seismic recording equipment for the Taku 2016 seismic survey. Thanks to Peter Burkett, Sridhar Anandakrishnan and Kiya Riverman for instrument support, and to Bernard Coakley, Bernard Hallet, Esther Babcock and some anonymous reviewers for their input and advice. Also thanks to the Consortium for Research in Elastic Wave Exploration Seismology (CREWES) for providing Matlab scripts that facilitated the seismic forward modeling. This project is funded by National Science Foundation grant number 130 4899 and supported in part by a University of Alaska Fairbanks Center for Global Change Student Research Grant with funds from the Cooperative Institute for Alaska Research.en_US
dc.language.isoen_USen_US
dc.publisherInternational Glaciological Societyen_US
dc.subjectglacier geophysicsen_US
dc.subjectglacial tillsen_US
dc.subjectglaciological instruments and methodsen_US
dc.subjectseismicsen_US
dc.subjectsubglacialen_US
dc.titleActive seismic studies in valley glacier settings: strategies and limitationsen_US
dc.typeArticleen_US
dc.description.peerreviewYesen_US
refterms.dateFOA2020-07-31T20:54:43Z
dc.identifier.journalJournal of Glaciologyen_US


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