Introduction

In the passive seismic imaging experiment as outlined in this volume (), full coverage of plane waves arriving from all azimuths and with all incidence angles is necessary to fully illuminate the subsurface. Either case of absent ray parameter constituents or over-representation of a few can confound the correlation approach to passive imaging. In this event, beam-steering analysis such as that undertaken in () may yield useful information, but will not provide images of the subsurface. Also problematic could be energy arriving from perfectly perpendicular azimuths to the linear receiver spread. This energy would have infinite ray parameter values, and be indistinguishable from vertical waves arriving from the deep earth. To explore this issue, I will offer three arguments in favor of the feasibility of the linear strategy.

One of the convenient issues about exploring this question, is that we are able to find the answer along the way while making plans to accommodate larger dimensionality. We can decimate our data set to address this specific concern. This is precisely the strategy employed in the first case where the MDI solar seismic data set is defined as a working model that we can decimate for the purposes of our concern. The second topic for discussion concerns the review of a patent application describing this acquisition strategy that claims informative results. Finally, seismologists at UBC have positive results inverting data collected with a linear array strategy across central Oregon. Through these three lines of evidence, I conclude that interpretable results are procurable from linear acquisition strategies.