Today's Menu: Global Seismic Tomography...

Prepared by Harmen Bijwaard


Welcome to this website. You have come to the right place for a magical tour through the colourful world of global seismic tomography. In short: seismic tomography is a technique to image the interior of the Earth with (pressure) waves that are generated by earthquakes. The method is comparable to that of the CT scan that is used to image the interior of the human body.
In 1999 I completed a PhD thesis on global seismic tomography at the Faculty of Earth Sciences of Utrecht University . Since 2000 I am involved in radiation research (including CT scan technology) at the Dutch National Institute for Public Health and the Environment (RIVM) .

For recent publications look at my curriculum vitae or my latest paper.
Apart from that, I also contribute to RIVM reports.

To illustrate seismic tomography imaging, you can click the above image to start an animation of a part of my 3D global tomography model. It depicts an isosurface of 0.5% higher than average wavespeed, showing sunken (subducted) plate material below Japan, the Izu-Bonin arc and the Kurile Islands from the Earth's surface to the core-mantle boundary (2900 km deep). Notice how the platelike structures in the upper part are connected with a huge volume in the lower mantle through a narrow 'chimney'. Earlier studies have hinted at the existence of such a plate "graveyard" in the lowermost mantle of this region.

Main course

Some time ago I wrote a Dutch introductory note about seismic tomography. It was meant for a magazine for sophomore students in the sciences ('de Vakidioot'), but no mathematical background is needed to understand it. For those of you that do not read Dutch I have also made an English version . For Earth scientists I have a short description of my PhD project.

And for the real insiders: Here's a picture of my PhD advisor, Wim Spakman, proudly showing some tomography images. This picture was taken at the European Geophysical Society meeting in Nice in 1998 (after the wine tasting...).

Results of my PhD research have been presented at the following conferences:

Main scientific publications resulting from my PhD research (for a complete list look at my c.v.):

Related (non-scientific) publications in (mostly Dutch) newspapers/magazines:

For Earth Sciences links I can recommend the tectonophysics page.
This page has also been included in the Science Lab.

Acknowledgements: The investigations have been supported by the Netherlands Geoscience Foundation (GOA) with financial aid from the Netherlands Organization for Scientific Research (NWO).


You are by now probably wondering whether you have this website all to yourself. Well, a number of people have been here before you, but there are still many more that haven't ....

Note that the number of website visits is no longer updated.

Harmen Bijwaard

curriculum vitae

This page was last updated September 1, 2008.