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Geodynamics

Geodynamics

The first observational evidence for a volcanically active Venus

and March 22, 2023
The first observational evidence for a volcanically active Venus
An artist’s impression of active volcanoes on Venus, depicting a subduction zone and an active volcano.
Credit: NASA/JPL-Caltech/Peter Rubin

Our neighbouring planet Venus is gaining popularity in the terrestrial planetary sciences, especially since the selection of three new Venus missions by NASA and ESA in 2021. Now, for the first time ever, scientists have directly observed surface changes that indicate active volcanism on Venus. This discovery was made with data from NASA’s 30-year-old Magellan mission and is only a small preview f ...[Read More]

Geodynamics 101 – Viscous anisotropy

March 16, 2023
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]

Study of the Lithospheric deformations, Earthquakes, Tsunamis, Volcanic eruptions and their imprints in Atmosphere using Space Geodetic Observations

and March 8, 2023
Study of the Lithospheric deformations, Earthquakes, Tsunamis, Volcanic eruptions and their imprints in Atmosphere using Space Geodetic Observations
Credit: Katsumi Hattori, presented in Ouzounov et al, 2018, Chapter 20

The fundamental of Space Geodesy is the observation of the dynamics of the Earth, such as its rotation on its axis, changes in shape, and the external gravitational field etc., which allow for the monitoring of the Earth system in general. Space Geodetic techniques, such as Global Navigation Satellite Systems (GNSS) / Global Positioning System (GPS), as well as Interferometric Synthetic Aperture R ...[Read More]

Ambient seismic wavefield: how noise can be a signal

February 23, 2023
Ambient seismic wavefield: how noise can be a signal
Trace of a seismogram recording background noise

Every now and then, the surface of our planet shakes violently during earthquakes like the recent magnitudes 7.8 and 7.5 Kahramanmaraş Earthquake Sequence in Türkiye. These vibrations are recorded by instruments called seismometers and are then processed and analyzed by seismologists to study the earthquake processes themselves as well as other deep Earth structures. Interestingly, seismometers al ...[Read More]