Source model for the Mw 6.7, 23 October 2002, Nenana Mountain earthquake (Alaska) from InSAR

Tim J. Wright; Z. Lu; Charles Wicks

doi:10.1029/2003gl018014

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Source model for the Mw 6.7, 23 October 2002, Nenana Mountain earthquake (Alaska) from InSAR

Tim J. Wright·Z. Lu·Charles Wicks

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Abstract

The 23 October 2002 Nenana Mountain Earthquake (M w ∼ 6.7) occurred on the Denali Fault (Alaska), to the west of the M w ∼ 7.9 Denali Earthquake that ruptured the same fault 11 days later. We used 6 interferograms, constructed using radar images from the Canadian Radarsat-1 and European ERS-2 satellites, to determine the coseismic surface deformation and a source model. Data were acquired on ascending and descending satellite passes, with incidence angles between 23 and 45 degrees, and time intervals of 72 days or less. Modeling the event as dislocations in an elastic half space suggests that there was nearly 0.9 m of right-lateral strike-slip motion at depth, on a near-vertical fault, and that the maximum slip in the top 4 km of crust was less than 0.2 m. The Nenana Mountain Earthquake increased the Coulomb stress at the future hypocenter of the 3 November 2002, Denali Earthquake by 30–60 kPa.

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Source-reported bounding extent: 62° to 64° latitude; -150° to -144° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeX RIS

Tim J. Wright, Z. Lu, Charles Wicks. 2003-09-30. Source model for the Mw 6.7, 23 October 2002, Nenana Mountain earthquake (Alaska) from InSAR. https://doi.org/10.1029/2003gl018014

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