气候变化领域集成服务门户(CCPortal): Strain Accumulation and Release Rate in Canada: Implications for Long-Term Crustal Deformation and Earthquake Hazards

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DOI	10.1029/2020JB020529
	Strain Accumulation and Release Rate in Canada: Implications for Long-Term Crustal Deformation and Earthquake Hazards
	Ojo A.O.; Kao H.; Jiang Y.; Craymer M.; Henton J.
发表日期	2021
ISSN	21699313
卷号	126 期号:4
英文摘要	To advance the understanding of crustal deformation and earthquake hazards in Canada, we analyze seismic and geodetic data sets and robustly estimate the crust strain accumulation and release rate by earthquakes. We find that less than 20% of the accumulated strain is released by earthquakes across the study area providing evidence for large-scale aseismic deformation. We attribute this to glacial isostatic adjustment (GIA) in eastern Canada, where predictions from the GIA model account for most of the observed discrepancy between the seismic and the geodetic moment rates. In western Canada, only a small percentage (<20%) of the discrepancy can be attributed to GIA-related deformation. We suspect that this may reflect the inaccuracy of the GIA model to account for heterogeneity in Earth structure or indicate that the present-day effect of GIA in western Canada is limited due to the fast response of the upper mantle to the deglaciation of the Cordillera Ice Sheet. At locations of previously identified seismic source zones, we speculate that the unreleased strain is been stored cumulatively in the crust and will be released as earthquakes in the future. The Gutenberg-Richter model predicts, however, that the recurrence interval can vary significantly in Canada, ranging from decades near plate boundary zones in the west to thousands of years in the stable continental interior. Our attempt to quantify the GIA-induced deformation provides the necessary first step for the integration of geodetic strain rates in seismic hazard analysis in Canada. © 2021. American Geophysical Union. All Rights Reserved.
英文关键词	crustal deformation; earthquake hazards; geodetic and seismic data; moment release rate; seismic hazard; strain accumulation
语种	英语
来源期刊	Journal of Geophysical Research: Solid Earth
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/187214
作者单位	Geological Survey of Canada, Natural Resources Canada, Sidney, BC, Canada; School of Earth and Ocean Science, University of Victoria, Victoria, BC, Canada; Canadian Geodetic Survey, Surveyor General Branch, Natural Resources Canada, Sidney, BC, Canada
推荐引用方式 GB/T 7714	Ojo A.O.,Kao H.,Jiang Y.,et al. Strain Accumulation and Release Rate in Canada: Implications for Long-Term Crustal Deformation and Earthquake Hazards[J],2021,126(4).
APA	Ojo A.O.,Kao H.,Jiang Y.,Craymer M.,&Henton J..(2021).Strain Accumulation and Release Rate in Canada: Implications for Long-Term Crustal Deformation and Earthquake Hazards.Journal of Geophysical Research: Solid Earth,126(4).
MLA	Ojo A.O.,et al."Strain Accumulation and Release Rate in Canada: Implications for Long-Term Crustal Deformation and Earthquake Hazards".Journal of Geophysical Research: Solid Earth 126.4(2021).