[1] The Pacific Northwest (PNW) has experienced voluminous intraplate volcanism over the past 17 Ma, beginning with the Steens/Columbia River flood basalts and continuing with the stillongoing volcanism in the High Lava Plains (HLP) and eastern Snake River Plain (SRP). Here we present two complementary datasets (SKS splitting and Rayleigh wave phase velocity anisotropy) that place constraints o...

a r t i c l e i n f o a b s t r a c t Improving the reliability and accuracy in the determination of the depth to velocity discontinuities in the Earth's mantle is essential for a better understanding of mantle dynamics, as well as for addressing such fundamental questions as the origin of mantle plumes and fate of subducted slabs. Most existing techniques that utilize receiver function stackin...

S U M M A R Y The 1909 April 14 Taiwan earthquake caused significant damage in Taipei. Most of the information on this earthquake available until now is from the written reports on its macro-seismic effects and from seismic station bulletins. In view of the importance of this event for assessing the shaking hazard in the present-day Taipei, we collected historical seismograms and station bullet...

[1] Rayleigh wave phase and amplitude data are analyzed to provide new insight into the velocity structure of the upper mantle beneath the Slave craton, in the northwestern Canadian Shield. We invert for phase velocities at periods between 20 s–142 s (with greatest sensitivity at depths of 28–200 km) using crossing ray paths from events recorded by the POLARIS broadband seismic network and the ...

The 900 instrument Mount St. Helens nodal array recorded continuous data for approximately two weeks in the summer of 2014 and was deployed contemporaneously with the active source component of the iMUSH experiment (imaging Magma Under St. Helens). Two distinct imaging methodologies are applied to node data 1) reverse time imaging (RTI) is used to automatically detect and locate microseismicity...

S U M M A R Y A velocity (Vs) and structure model is derived for the Los Angeles Basin, California based on ambient-noise surface wave and receiver-function analysis, using data from a low-cost, short-duration, dense broad-band survey (LASSIE) deployed across the basin. The shear wave velocities show lateral variations at the Compton-Los Alamitos and the Whittier Faults. The basement beneath th...

[1] Broadband data from the Meso-America Subduction Experiment (MASE) line in central Mexico were used to image the subducted Cocos plate and the overriding continental lithosphere beneath central Mexico using a generalized radon transform based migration. Our images provide insight into the process of subducting relatively young oceanic lithosphere and its complex geometry beneath continental ...

The results of a recent large scale three-dimensional study of P velocity beneath North America are analyzed from the point of view of the search for the fossil Farallon plate in the mantle beneath the western edge of the North American continent. The large scale velocity structure obtained in the western U.S. is compatible with independent finer scale seismic studies and suggests that the Fara...