Imaging P-to-S conversions with multichannel receiver functions

We present a new methodology in the direct imaging of P-to-S converted phases recorded on broadband seismic arrays. Our approach is based on conventional three-component array processing and receiver function techniques with the key addition of a weighted stack based on an aerial smoothing function. This creates synthetic arrays with a specified aperture whose image points vary continuously across the array. With this approach, it is possible to interpolate data from an array of broadband stations onto an arbitrarily fine grid. We have applied this technique to a single deep event recorded by the Lodore broadband array, located in northern Colorado and southern Wyoming. The resulting images show distinct differences in crustal structure across the array, and also image major upper mantle discontinuities.