Tim uses physics to study processes within the Earth. He uses seismic waves to image structures and measure their physical properties on scales from 10s of cm to 100s of km. He also uses numerical modelling to understand how physical processes lead to the geological features that we observe. He works with collaborators in mulitple disciplines within the Earth sciences and engineering. For example, he has worked to measusre the physical properties within the shallowest 10-20 m beneath the seabed which are critical for offshore engineering, and showed that the power capacity of electrical power cables buried in the seabed is strongly affected by the type of sediment. He uses similar methods to study active tectonics within the Earth, and to investigate the formation and evolution of the oceanic lithosphere that covers 70% of the Earth's surface.