Strike-Slip Fault Terminations at Seismogenic Depths: The Structure and Kinematics of the Glacier Lakes Fault, Sierra Nevada United States
[1] Structural complexity is common at the terminations of earthquake surface ruptures; similar deformation may therefore be expected at the end zones of earthquake ruptures at depth. The 8.2 km long Glacier Lakes fault (GLF) in the Sierra Nevada is a left-lateral strike-slip fault with a maximum ob...
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ftutahsudc:oai:digitalcommons.usu.edu:geology_facpub-1003 2023-05-15T17:08:21+02:00 Strike-Slip Fault Terminations at Seismogenic Depths: The Structure and Kinematics of the Glacier Lakes Fault, Sierra Nevada United States Kirkpatrick, J. D. Shipton, Z. K. Evans, James P. Micklethwaite, S. Lim, S. J. McKillop, Peter R. American Geophysical Union 2008-01-01T08:00:00Z application/pdf https://digitalcommons.usu.edu/geology_facpub/4 https://digitalcommons.usu.edu/cgi/viewcontent.cgi?article=1003&context=geology_facpub unknown Hosted by Utah State University Libraries https://digitalcommons.usu.edu/geology_facpub/4 https://digitalcommons.usu.edu/cgi/viewcontent.cgi?article=1003&context=geology_facpub Copyright for this work is held by the author. Transmission or reproduction of materials protected by copyright beyond that allowed by fair use requires the written permission of the copyright owners. Works not in the public domain cannot be commercially exploited without permission of the copyright owner. Responsibility for any use rests exclusively with the user. For more information contact the Institutional Repository Librarian at digitalcommons@usu.edu. PDM Geosciences Faculty Publications fault damage zone earthquake rupture termination pseudotachylyte Earth Sciences Geology Physical Sciences and Mathematics text 2008 ftutahsudc 2022-03-07T22:18:37Z [1] Structural complexity is common at the terminations of earthquake surface ruptures; similar deformation may therefore be expected at the end zones of earthquake ruptures at depth. The 8.2 km long Glacier Lakes fault (GLF) in the Sierra Nevada is a left-lateral strike-slip fault with a maximum observed displacement of 125 m. Within the fault, pseudotachylytes crosscut cataclasites, showing that displacement on the GLF was accommodated at least partly by seismic slip. The western termination of the GLF is defined by a gradual decrease in the displacement on the main fault, accompanied by a 1.4 km wide zone of secondary faulting in the dilational quadrant of the GLF. The secondary faults splay counterclockwise from the main fault trace forming average angles of 39° with the main fault. Slip vectors defined by slickenlines plunge more steeply west for these splay faults than for the GLF. Static stress transfer modeling shows that the orientations of the splays, and the plunge of displacement on those splays, are consistent with displacement on the main fault. The GLF termination structure shows that structural complexity is present at the terminations of faults at seismogenic depths and therefore ruptures that propagate beyond fault terminations, or through step overs between two faults, will likely interact with complex secondary fault structures. Models of dynamic rupture propagation must account for the effect of preexisting structures on the elastic properties of the host rock. Additionally, aftershock distributions and focal mechanisms may be controlled by the geometry and kinematics of structures present at fault terminations. Text Long Glacier Utah State University: DigitalCommons@USU Long Glacier ENVELOPE(-96.717,-96.717,-72.500,-72.500) |
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Utah State University: DigitalCommons@USU |
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ftutahsudc |
language |
unknown |
topic |
fault damage zone earthquake rupture termination pseudotachylyte Earth Sciences Geology Physical Sciences and Mathematics |
spellingShingle |
fault damage zone earthquake rupture termination pseudotachylyte Earth Sciences Geology Physical Sciences and Mathematics Kirkpatrick, J. D. Shipton, Z. K. Evans, James P. Micklethwaite, S. Lim, S. J. McKillop, Peter R. Strike-Slip Fault Terminations at Seismogenic Depths: The Structure and Kinematics of the Glacier Lakes Fault, Sierra Nevada United States |
topic_facet |
fault damage zone earthquake rupture termination pseudotachylyte Earth Sciences Geology Physical Sciences and Mathematics |
description |
[1] Structural complexity is common at the terminations of earthquake surface ruptures; similar deformation may therefore be expected at the end zones of earthquake ruptures at depth. The 8.2 km long Glacier Lakes fault (GLF) in the Sierra Nevada is a left-lateral strike-slip fault with a maximum observed displacement of 125 m. Within the fault, pseudotachylytes crosscut cataclasites, showing that displacement on the GLF was accommodated at least partly by seismic slip. The western termination of the GLF is defined by a gradual decrease in the displacement on the main fault, accompanied by a 1.4 km wide zone of secondary faulting in the dilational quadrant of the GLF. The secondary faults splay counterclockwise from the main fault trace forming average angles of 39° with the main fault. Slip vectors defined by slickenlines plunge more steeply west for these splay faults than for the GLF. Static stress transfer modeling shows that the orientations of the splays, and the plunge of displacement on those splays, are consistent with displacement on the main fault. The GLF termination structure shows that structural complexity is present at the terminations of faults at seismogenic depths and therefore ruptures that propagate beyond fault terminations, or through step overs between two faults, will likely interact with complex secondary fault structures. Models of dynamic rupture propagation must account for the effect of preexisting structures on the elastic properties of the host rock. Additionally, aftershock distributions and focal mechanisms may be controlled by the geometry and kinematics of structures present at fault terminations. |
author2 |
American Geophysical Union |
format |
Text |
author |
Kirkpatrick, J. D. Shipton, Z. K. Evans, James P. Micklethwaite, S. Lim, S. J. McKillop, Peter R. |
author_facet |
Kirkpatrick, J. D. Shipton, Z. K. Evans, James P. Micklethwaite, S. Lim, S. J. McKillop, Peter R. |
author_sort |
Kirkpatrick, J. D. |
title |
Strike-Slip Fault Terminations at Seismogenic Depths: The Structure and Kinematics of the Glacier Lakes Fault, Sierra Nevada United States |
title_short |
Strike-Slip Fault Terminations at Seismogenic Depths: The Structure and Kinematics of the Glacier Lakes Fault, Sierra Nevada United States |
title_full |
Strike-Slip Fault Terminations at Seismogenic Depths: The Structure and Kinematics of the Glacier Lakes Fault, Sierra Nevada United States |
title_fullStr |
Strike-Slip Fault Terminations at Seismogenic Depths: The Structure and Kinematics of the Glacier Lakes Fault, Sierra Nevada United States |
title_full_unstemmed |
Strike-Slip Fault Terminations at Seismogenic Depths: The Structure and Kinematics of the Glacier Lakes Fault, Sierra Nevada United States |
title_sort |
strike-slip fault terminations at seismogenic depths: the structure and kinematics of the glacier lakes fault, sierra nevada united states |
publisher |
Hosted by Utah State University Libraries |
publishDate |
2008 |
url |
https://digitalcommons.usu.edu/geology_facpub/4 https://digitalcommons.usu.edu/cgi/viewcontent.cgi?article=1003&context=geology_facpub |
long_lat |
ENVELOPE(-96.717,-96.717,-72.500,-72.500) |
geographic |
Long Glacier |
geographic_facet |
Long Glacier |
genre |
Long Glacier |
genre_facet |
Long Glacier |
op_source |
Geosciences Faculty Publications |
op_relation |
https://digitalcommons.usu.edu/geology_facpub/4 https://digitalcommons.usu.edu/cgi/viewcontent.cgi?article=1003&context=geology_facpub |
op_rights |
Copyright for this work is held by the author. Transmission or reproduction of materials protected by copyright beyond that allowed by fair use requires the written permission of the copyright owners. Works not in the public domain cannot be commercially exploited without permission of the copyright owner. Responsibility for any use rests exclusively with the user. For more information contact the Institutional Repository Librarian at digitalcommons@usu.edu. |
op_rightsnorm |
PDM |
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1766064101625167872 |