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Characterizing The 410 Km Discontinuity Low-Velocity Layer Beneath The La Ristra Array In The North American Southwest, J. J. Jasbinsek, Ken Dueker, S. M. Hansen
Characterizing The 410 Km Discontinuity Low-Velocity Layer Beneath The La Ristra Array In The North American Southwest, J. J. Jasbinsek, Ken Dueker, S. M. Hansen
Ken Dueker
Receiver functions recorded by the 54-station 920 km long Program for Array Seismic Studies of the Continental Lithosphere-Incorporated Research Institutions for Seismology Colorado Plateau/Rio Grande Rift Seismic Transect Experiment (LA RISTRA) line array display a pervasive negative polarity P to S conversion (Pds) arrival preceding the positive polarity 410 km discontinuity arrival. These arrivals are modeled as a low-velocity layer atop the 410 km discontinuity (410-LVL) and are inverted for a velocity profile via a grid search using a five-parameter linear gradient velocity model. Model parameter likelihood and correlations are assessed via calculation of one-and two-dimensional marginal posterior probability distributions. …
A Sporadic Low-Velocity Layer Atop The Western Us Mantle Transition Zone And Short-Wavelength Variations In Transition Zone Discontinuities, B. Schmandt, Ken Dueker, S. M. Hansen, J. J. Jasbinsek, Z. Zhang
A Sporadic Low-Velocity Layer Atop The Western Us Mantle Transition Zone And Short-Wavelength Variations In Transition Zone Discontinuities, B. Schmandt, Ken Dueker, S. M. Hansen, J. J. Jasbinsek, Z. Zhang
Ken Dueker
Teleseismic receiver function analysis of data from six dense arrays in the western U. S. is used to investigate mantle transition zone (MTZ) discontinuities and the prevalence of a low-velocity layer atop the 410 km discontinuity (410-LVL). Negative polarity Ps arrivals indicative of a low-velocity layer with a top 25-60 km above the 410 are identified in 8-11 out of 18 stacks of receiver functions from highly sampled back azimuth corridors. The 410-LVL is interpreted as partial melt resulting from upwelling of hydrated mantle across a water solubility contrast at the 410. The 669 km mean depth of the 660 …
Signal-To-Noise Ratios Of Teleseismic Receiver Functions And Effectiveness Of Stacking For Their Enhancement, I. B. Morozov, Ken G. Dueker
Signal-To-Noise Ratios Of Teleseismic Receiver Functions And Effectiveness Of Stacking For Their Enhancement, I. B. Morozov, Ken G. Dueker
Ken Dueker
[1] We present a method for the measurement of spatially variable signal-to-noise (S/N) ratios in multichannel teleseismic receiver function (RF) images. The S/N ratio is defined as a measure of coherency of the final image, and the approach is applicable to any RF imaging technique that employs mapping of the records into depth followed by their summation as the final signal enhancement step. In such methods, all of the converted phases become horizontally aligned in the depth domain, and their coherent (signal) and incoherent (noise) components can be estimated by using stacking statistics. For 10 locations along two subarrays of …