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• 1. [Article] Seismic anisotropy beneath the Juan de Fuca plate system: Evidence for heterogeneous mantle flow

  This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by the Geological Society of America and can be found at: http://geology.gsapubs.o...

  Citation × Citation Citation Abstract Copy Title: Seismic anisotropy beneath the Juan de Fuca plate system: Evidence for heterogeneous mantle flow Author: Braunmiller, Jochen, Bodmer, Miles, Toomey, Douglas R., Nabelek, John, Hooft, Emilie E. This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by the Geological Society of America and can be found at: http://geology.gsapubs.org/ Title: Seismic anisotropy beneath the Juan de Fuca plate system: Evidence for heterogeneous mantle flow Author: Braunmiller, Jochen, Bodmer, Miles, Toomey, Douglas R., Nabelek, John, Hooft, Emilie E. This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by the Geological Society of America and can be found at: http://geology.gsapubs.org/ Close

• 2. [Article] Segmentation of the Blanco Transform Fault Zone from earthquake analysis: Complex tectonics of an oceanic transform fault

  Copyrighted by American Geophysical Union.

  Citation × Citation Citation Abstract Copy Title: Segmentation of the Blanco Transform Fault Zone from earthquake analysis: Complex tectonics of an oceanic transform fault Author: Braunmiller, Jochen, Nábělek, John Copyrighted by American Geophysical Union. Title: Segmentation of the Blanco Transform Fault Zone from earthquake analysis: Complex tectonics of an oceanic transform fault Author: Braunmiller, Jochen, Nábělek, John Copyrighted by American Geophysical Union. Close

• 3. [Article] Seismotectonics of the Explorer region

  Copyrighted by American Geophysical Union.

  Citation × Citation Citation Abstract Copy Title: Seismotectonics of the Explorer region Author: Braunmiller, Jochen, Nábělek, John Copyrighted by American Geophysical Union. Title: Seismotectonics of the Explorer region Author: Braunmiller, Jochen, Nábělek, John Copyrighted by American Geophysical Union. Close

• 4. [Article] Seismotectonics of the explorer region and of the Blanco Transform Fault Zone

  In this thesis, we present the first detailed, long-term seismotectonic studies of oceanic ridge-transform systems. The proximity of the Juan de Fuca plate to a network of broadband seismic stations in ...

  Citation × Citation Citation Abstract Copy Title: Seismotectonics of the explorer region and of the Blanco Transform Fault Zone Author: Braunmiller, Jochen In this thesis, we present the first detailed, long-term seismotectonic studies of oceanic ridge-transform systems. The proximity of the Juan de Fuca plate to a network of broadband seismic stations in western North America provides a unique synergy of interesting tectonic targets, high seismicity, and recording capabilities. Our main tools are earthquake source parameters, determined by robust waveform modeling techniques, and precise earthquake locations, determined by joint epicenter relocation. Regional broadband data are used to invert for the source moment tensors of the frequent, moderate-sized (M ≥ 4) earthquakes; this analysis began 1994. We include Harvard centroid moment-tensors available since 1976 for larger (M ≥ 5) earthquakes. Two studies comprise the main part of this thesis. In the first, we determine the current tectonics of Explorer region offshore western Canada. Earthquake slip vector azimuths along the Pacific-Explorer boundary require an independent Explorer plate. We determine its rotation pole and provide a tectonic model for the plate's history over the last 2 Ma. Plate motion changes caused distributed deformation in the plate's southeast corner and caused a small piece in the southwest corner to transfer to the Pacific plate. Capture of the plate fragment indicates that preserved fragments not necessary represent entire microplates. In the second study, we investigate seismicity and source parameters along the Blanco Transform Fault Zone (BTFZ). The deformation style-- strike slip and normal faulting-- correlates well with observed changes in BTFZ's morphology. We infer that Blanco Ridge probably consists of two fault segments, that several parallel faults are active along BTFZ's west part, and that Cascadia Depression possibly is a short spreading center. The slip distribution along the BTFZ is highly variable, although seismicity could account for the full plate motion rate along the entire BTFZ. The final part is a short study where we locate an earthquake in the tectonically active Mendocino triple junction region offshore northern California using land and offshore data. The precise location may be useful as a master event for relocating other earthquakes. Title: Seismotectonics of the explorer region and of the Blanco Transform Fault Zone Author: Braunmiller, Jochen In this thesis, we present the first detailed, long-term seismotectonic studies of oceanic ridge-transform systems. The proximity of the Juan de Fuca plate to a network of broadband seismic stations in western North America provides a unique synergy of interesting tectonic targets, high seismicity, and recording capabilities. Our main tools are earthquake source parameters, determined by robust waveform modeling techniques, and precise earthquake locations, determined by joint epicenter relocation. Regional broadband data are used to invert for the source moment tensors of the frequent, moderate-sized (M ≥ 4) earthquakes; this analysis began 1994. We include Harvard centroid moment-tensors available since 1976 for larger (M ≥ 5) earthquakes. Two studies comprise the main part of this thesis. In the first, we determine the current tectonics of Explorer region offshore western Canada. Earthquake slip vector azimuths along the Pacific-Explorer boundary require an independent Explorer plate. We determine its rotation pole and provide a tectonic model for the plate's history over the last 2 Ma. Plate motion changes caused distributed deformation in the plate's southeast corner and caused a small piece in the southwest corner to transfer to the Pacific plate. Capture of the plate fragment indicates that preserved fragments not necessary represent entire microplates. In the second study, we investigate seismicity and source parameters along the Blanco Transform Fault Zone (BTFZ). The deformation style-- strike slip and normal faulting-- correlates well with observed changes in BTFZ's morphology. We infer that Blanco Ridge probably consists of two fault segments, that several parallel faults are active along BTFZ's west part, and that Cascadia Depression possibly is a short spreading center. The slip distribution along the BTFZ is highly variable, although seismicity could account for the full plate motion rate along the entire BTFZ. The final part is a short study where we locate an earthquake in the tectonically active Mendocino triple junction region offshore northern California using land and offshore data. The precise location may be useful as a master event for relocating other earthquakes. Close

• 5. [Article] A seasonally modulated earthquake swarm near Maupin, Oregon

  This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by Oxford University Press on behalf of The Royal Astronomical Society. The published article can ...

  Citation × Citation Citation Abstract Copy Title: A seasonally modulated earthquake swarm near Maupin, Oregon Author: Braunmiller, Jochen, Tréhu, Anne M., Nábělek, John L. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by Oxford University Press on behalf of The Royal Astronomical Society. The published article can be found at: http://gji.oxfordjournals.org/. Title: A seasonally modulated earthquake swarm near Maupin, Oregon Author: Braunmiller, Jochen, Tréhu, Anne M., Nábělek, John L. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by Oxford University Press on behalf of The Royal Astronomical Society. The published article can be found at: http://gji.oxfordjournals.org/. Close