Comparisons between non-interferometric and interferometric passive surface wave imaging methods - Towards linear receiver array

Passive seismic methods in highly populated urban areas have gained much attention from geophysics and civil engineering communities. Linear arrays are usually deployed for passive surface-wave investigations because of their high efficiency and convenience, and methods commonly used for linear arrays include passive multichannel analysis of surface wave (PMASW), refraction microtremor (ReMi), multichannel analysis of passive surface waves (MAPS) and spatial autocorrelation (SPAC). These passive surface wave methods can be further grouped as non-interferometric methods (PMASW, ReMi, etc) and interferometric methods (MAPS, SPAC, etc). It is well known that seismic interferometry method is able to retrieve greeńs function between inter-station pairs based on passive seismic data, which is also the underlying physics for interferometric passive surface wave methods. There is no theoretical proof to verify the feasibility of noninterferometric methods, although they are popular and effective in near-surface imaging. In this work, we use numerical solutions to understand how non-interferometric methods work and demonstrate how to estimate their biases with imaging resolution or array smoothing function (ASF). Finally, we present comprehensive comparisons between different passive surface wave methods with a real-world example.