A new global S-wave model has recently been published in Geophysical Journal International. While this sounds exciting enough to tomographers and geodynamicists, this model has been constructed in a rather avant-garde way, too. It is one out of only two global tomographic models ever to be made based on the Earth’s background oscillations, that is long-periodic seismic noise also known as Earth’s ...[Read More]
Brewing wiggles on Mars
Creating 1 Hz-seismograms in a 3-D Earth model, and comparing them to observed body waves, is a dream that’s today still too expensive for routine use. But even tackling the problem for a spherically symmetric Earth poses certain challenges. Recently, a new tool entered the stage (you might have followed the Solid Earth discussion): Instaseis allows users to extract seismograms for a spherically s ...[Read More]
To b, not to b, or to b with Voronoi?
The b-value is that parameter of the Gutenberg-Richter relation which controls the ratio of small to large earthquakes. Intriguing temporal and spatial variations of the b-value have been reported in recent years, for example sudden b-value changes at active fault zones. Are such sharp spatial b-value variations merely a result of crude undersampling? To address this unsettling question, a recentl ...[Read More]