Seismic velocities and composition of the Canadian crust
department or school: Science, Faculty of
department or school: Earth, Ocean and Atmospheric Sciences, Department of
data provider: DSpace
degree campus: UBCV
creator: Postlethwaite, Benjamin
issued: 2014-05-06T14:04:18Z
issued: 2014
related degree: Master of Science - MSc
degree grantor: University of British Columbia
description: It has been suggested that processes driving crustal formation in the Archean and Proterozoic were dissimilar and produced crusts with unique bulk properties and average thicknesses. The calibration of models based on evolving mantle fractionation or mantle convection style require accurate estimates of the geological and geophysical properties of crustal provinces to better constrain the details of crustal formation. Fifteen years of publicly accessible teleseismic data from all available Canadian seismic stations are binned in horizontal slowness and deconvolved into receiver functions. We apply a stacking method to retrieve estimates of the bulk crustal velocity ratio V P /V S and thickness H from these data under the assumption of locally 1-D structure. We also investigate modifications to this approach that can allow discrimination of V S and V P under certain conditions. Bootstrap error analysis is performed for each station dataset and subsets of these measurements are compared with results for matching stations from previous studies. Analysis of results in conjunction with additional velocity estimates from active source seismic studies and a seismic property database affords improved constraints on bulk geological composition of the Canadian landmass that are used to evaluate competing models of crustal formation.
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/46687
note: Seismic velocities andcomposition of the CanadiancrustbyBen PostlethwaiteB.Sc., The University of British Columbia, 2011A THESIS SUBMITTED IN PARTIAL FULFILLMENT OFTHE REQUIREMENTS FOR THE DEGREE OFMASTER OF SCIENCEinThe Faculty of Graduate and Postdoctoral Studies(Geophysics)THE UNIVERSITY OF BRITISH COLUMBIA(Vancouver)May 2014c© Ben Postlethwaite 2014AbstractIt has been suggested that processes driving crustal formation in the Archean and Proterozoicwere dissimilar and produced crusts with unique bulk properties and average thicknesses.The calibration of models based on evolving mantle fractionation or mantle convection stylerequire accurate estimates of the geological and geophysical properties of crustal provincesto better constrain the details of crustal formation. Fifteen years of publicly accessibleteleseismic data from all available Canadian seismic stations are binned in horizontal slownessand deconvolved into receiver functions. We apply a stacking method to retrieve estimates ofthe bulk crustal velocity ratio VP/VS and thickness H from these data under the assumptionof locally 1-D structure. We also investigate modifications to this approach that can allowdiscrimination of VS and VP under certain conditions. Bootstrap error analysis is performedfor each station dataset and subsets of these measurements are compared with results formatching stations from previous studies. Analysis of results in conjunction with additionalvelocity estimates from active source seismic studies and a seismic property database affordsimproved constraints on bulk geological composition of the Canadian landmass that are usedto evaluate competing models of crustal formation.iiPrefaceTeleseismic data discussed in chapter 2 section 2.1 was processed using Python scripts writtenby myself and a set of shell scripts based off previous work by Michael Bostock. Deconvolutionalgorithms and coordinate transformation algorithms are likewise interpreted from previouswork by Michael Bostock. …
has type: Thesis/Dissertation
date issued: 2014-09
is shown at: 10.14288/1.0167442
language: eng
degree discipline: Geophysics
provider: Vancouver : University of British Columbia Library
publisher: University of British Columbia
rights: Attribution-NonCommercial-NoDerivs 2.5 Canada
rights URI: http://creativecommons.org/licenses/by-nc-nd/2.5/ca/
scholar level: Graduate
type: Text
identifier URI: http://hdl.handle.net/2429/46687