Large‐scale crustal structure beneath Singapore using receiver functions from a dense urban nodal array

Abstract

Geophysics has a role to play in the development of “smart cities”. This is particularly true for Singapore, one of the world's most densely populated countries. Imaging of Singapore's subsurface is required to identify geological faults, model shaking from future earthquakes, and provide a framework for underground development. A noninvasive geophysical technique that is well suited for urban areas is passive seismic surveys using compact seismic instruments called nodes. Here we image Singapore's crustal structure using receiver functions generated by a 40‐day deployment of a 88 station 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.