Karen H Lythgoe, Miranda Ong Su Qing, Shengji Wei

Geophysics has a role to play in the development of smart cities, for example through geohazard mitigation and subsurface imaging for underground construction. This is particularly true for Singapore, one of the worlds most densely populated countries. Imaging of Singapores subsurface is required to identify geological faults, model shaking from future earthquakes and provide a framework for underground development. A non-invasive geophysical technique that is well suited for urban areas is passive seismic surveys using nodes. Here, we image Singapores crustal structure using receiver functions generated by a 40-day deployment of a dense nodal array. We generate high resolution receiver functions, despite the noisy environment and short recording time and also create common-conversion point images. Our results reveal a complex crustal structure, containing multiple discontinuities. Azimuthal variations indicate a distinct change in crustal structure on either side of the postulated Bukit Timah fault, which has implications for seismic hazard.