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Geodynamics

geodynamics 101

Don’t Stop Me Now: A Fracture Mechanics Perspective on Earthquake Nucleation

Schematic for a possible earthquake nucleation scenario. Inset figure adapted after Lebihain et al. (2021) and McLaskey (2019).

How do earthquakes start? Earthquakes occur when a block of rock rapidly slides past another along an interface or a discontinuity in the medium and release energy in the form of seismic waves. Turns out, the surface of the earth is riddled with a lot of these discontinuities, which we call “faults”. If we plot the locations of earthquakes on a world map (Figure 1a), we will see that they highligh ...[Read More]

Geodynamics 101 – Viscous anisotropy

Geodynamics 101 – Viscous anisotropy

We are living in an anisotropic world. From rock-building crystals, ice, and trees growing in your garden to your favourite slice of cake many materials or objects has some anisotropic behaviour. What does this mean? Anisotropy (non-isotropy) implies that a material property depends on the direction of the measurement. In geodynamics we often talk about seismic anisotropy, originating from microsc ...[Read More]