Investigating Subsurface Properties of the Shallow Lunar Crust using
Seismic Interferometry on Synthetic and Recorded Data
Abstract
In the past few years, the remarkable progress of commercially operated
spacecrafts, the success with reusable rocket engines, as well as the
international competition to explore space, has led to a substantial
acceleration of activities in the design and preparation of ambitious
future lunar missions. In the search for ice and/or cavities imaging the
shallow subsurface structure is of vital importance. Hereby, previous
studies have shown that seismic interferometry is a promising method to
investigate the subsurface properties from passive lunar data. In this
study, we want to evaluate the potential of this method further by
examining the required duration of seismic measurements and the
influence of scattering on the Green´s function retrieval. Therefore, we
applied seismic interferometry to both measured Apollo 17 data and
synthetic data. Our findings indicate that, under optimal conditions, a
few hours of data are sufficient when using the method of time-scaled
phase-weighted stack (ts-PWS). However, this strongly depends on the
inter-station distance, the orientation towards the principal noise
sources, and the timing of the measurement during the lunar cycle.
Additionally, we were able to reproduce the measured data using
numerical simulations in 2D. The synthetic results show that scattering
effects clearly influence the Green´s function extraction, especially
for larger station distances.