Developing regional discriminants (RDs) at any given seismic station requires a ground-truth database of waveforms from both earthquakes and explosions. Recently installed stations used for seismic monitoring have no single charge explosions on which to base discriminants. We have developed a procedure to map information from surrogate stations, having a long recording history, to newly installed operational stations. We investigated a method to compute transfer functions using known effective 13Ds for a database of earthquakes and explosions located near the Lop Nor nuclear test site and recorded at the KNET array in Kyrgyzstan. For specific source-station paths, transfer functions work well. However, preliminary analysis of India and Pakistan nuclear tests indicate strong azimuthal dependence in the construction of reliable transfer functions. The success of the preliminary work suggests we can apply the same technique to calibrate the recently installed MKAR array using the Global Seismic Network station MAKZ as a surrogate. Both MKAR, an 11-element array operational since 2000, and MAKZ (including its earlier counterpart MAK), operating very broadband instruments since 1994, are located in Eastern Kazakhstan and separated by 25 km. To perform the calibration requires additional considerations not taken into account during the initial investigation: (1) utilizing amplitude spectra, rather than using RDs, to calculate transfer functions; (2) computing transfer functions for a range of azimuths, as we believe the transfer function are azimuthally dependent; and (3) determining whether working with each array element separately or developing a single-input/multiple-output model will provide more stable results and better error estimates
