1. A method of processing microseismic data, comprising: acquiring three-component microseismic waveform data with at least one receiver; determining a measure of waveform fit in the frequency-domain comprising: constructing, in the frequency-domain an amplitude misfit functional wherein constructing includes utilizing time reversal determined by a matrix inversion; estimating source parameters and/or model parameters; and displaying microseismicity results using estimated source parameters and/or model parameters; and further comprising a joint χ 2 likelihood function comprising the amplitude misfit functional and a cross-phase functional, constructed in the frequency-domain wherein constructing includes utilizing time reversal determined by a matrix inversion, with a multivariate prior probability distribution; and maximizing or sampling a posterior probability function using global search techniques.