New publication in Geophysical Journal International

Mapping the edge of subducted slabs in the lower mantle beneath southern AsiaOn March 23rd, 2022, TIMEleSS student Federica Rochira, published a new paper in Geophysical Journal international: Mapping the edge of subducted slabs in the lower mantle beneath southern Asia.

In this work, Federica Rochira, Lina Schumacher, and Christine Thomas from the Westfälische Wilhelms-Universität, Münster, investigate the presence of seismic structures in the Earth’s mantle by searching for seismic signals, and in particular signals from the edges of subducted slabs. They rely on an original approach that uses was that travel off the great circle path direction and are reflected or scattered off structures in the lower mantle and focus on areas of current and past subduction beneath Eurasia by using events from Indonesia and Japan recorded at the broad-band stations in Germany, Morocco and Namibia. Applying seismic array techniques, they measure the direction and traveltime of the out-of-plane arrivals and backtrace them to their location of reflection/scattering.

The results of the work indicate that most of the backtraced reflectors are located beneath southern Asia and are found shallower than 1500 km depth. They correlate well with the edges of prominent high velocity anomalies in tomographic inversions beneath southern Asia, which have been interpreted as remnants of fossil slabs of the subduction of the Tethys Oceans. They also observe few reflectors deeper than 1600 km that are located away from subducting regions and their positions coincide with the eastern edge of the African low velocity anomaly.

These observations suggest that the presence of reflectors in the mid-lower mantle is not exclusively related to current or past subducting regions, but widespread throughout the mantle.

The full details are in the following publication: F. Rochira, L. Schumacher, C. Thomas, Mapping the edge of subducted slabs in the lower mantle beneath southern Asia, Geophysical Journal International, 230, 1239–1252 (2022) [doi: 10.1093/gji/ggac110]

Seismology training for TIMEleSS members!

TIMEleSS February 2020 seismology trainingTIMEleSS members are in Münster!

TIMEleSS PI C. Thomas is hosting a seismology training for TIMEleSS students.

Participants include TIMEleSS students E. Ledoux, J. Gay, F. Rochira, M. Krug, and guests from WWU Münster Mineralogy and Seismology labs.

The training is the opportunity to move on to the next step in the TIMEleSS project: combining Mineral Physics and Seismology observations and try to say something about deep mantle processes!

We are hiring!

Post-doc position on wave propagation in structures and microstructures at the University of Lille, France

The TIMEleSS project is looking for a post-doctoral fellow. The position is available for 1 year and extendable. The position is attached to the Earth and Planetary Materials group the Unité Matériaux et Transformations, at the Université de Lille, France, with strong collaborations with the Institute for Geophysics at the University of Münster.

The post-doc will be in charge of  simulating wave propagation in structures and microstructures with the aim of interpreting deep Earth seismic observables.

The candidate should have a strong background in deep Earth seismology and/or wave propagation in complex media and/or mineral physics and will be in charge of connecting mineral physics knowledge of phase transformations and microstructures in the Earth’s mantle to potential observations of seismic reflections and scattering.

Details on the position, conditions, and requirements can be found in the following document. The review of of applications will start by January 31st 2020 and will continue until the position is filled. The position is expected to start in the spring or the summer of 2020.