Exploring Masw Surveys With Random Receiver Arrays For Future Lunar Exploration

Abstract

Understanding the physical and engineering properties within the upper 30m of the Lunar subsurface will be critical as Lunar exploration advances and deployment of large structures or landing of large spacecraft on the surface becomes necessary. Advances in multi-channel seismic acquisition, either active or passive, in acquiring reliable 1-D or 2-D shear wave velocity profiles have greatly improved our ability to determine the engineering properties (e.g. Poisson’s ratio) of shallow subsurface, especially when using the multi-channel analysis of surface waves (MASW) technique. A new scheme of using randomly distributed geophones (likely deployed from a mortar-type device) instead of a conventional linear array is necessary for Lunar exploration because of the logistical constraints in arranging a linear or circular array robotically. This random geometry is also evaluated (a) for validity or any potential improvements in the resolution of the dispersion image and (b) as more accurate method for assessing azimuthal variations in the subsurface geology. Results indicate that the random array geometry can be used for MASW survey to produce robust dispersion curves that can be used for the subsequent analyses for the subsurface engineering parameters.