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Modelling Gondwana dispersal quantitatively using ocean-floor images from satellite altimetry has provided many challenges. Not least has been an internally consistent solution for the process of ocean creation around the Bouvet triple junction in the Late Jurassic and Early Cretaceous. The key to success has been understanding the growth of the Weddell Sea in this time interval. An Antarctica-South America Corridor has been identified in the ocean-floor topography that controls the relative pace of Africa and South America, particularly through the Cretaceous Quiet Zone, and hence closing the plate circuit credibly. Playing out what-if scenarios in the Atlas software and refining solutions iteratively is tedious and time consuming. What may appear as an open-ended problem inviting 'blue sky thinking' is in fact constrained by data and what is not only geometrically possible but also plausible in animation. The most recent illustration of the model is Animation N. Rotation poles for all the fragments are lsted here.

The first half of 2026 has seen stability achieved in the model itself and particularly in the uninterrupted growth of the small areas of oceanic crust that emerged between the micro-fragments created during Gondwana disruption off South Africa. Elimination of small errors in the rotation file seems to have finally run its course. In addition, the model now seems to offer explanations for relatively minor features in ocean-floor topography, such as the coeval emplacement of the middle section of the Mozambique Ridge with the Astrid Ridge off Antarctica Animation L. There are many lines of research that could be pursued to extend this - but at the cost of making the basic model better known to others who can follow up such ideas more widely.

A poster was presented at the Netherlands Earth Science Congress in April this year. This is the 7th in a series of posters that now provide a rapid introduction to many aspects of the work, accessible on the Research Updates page. More than 20 Animations form an educational resource that will hopefully help to inspire a new generation of scientists to think about how crustal geology works.

It is now proposed to write a Research Round-up (with extensive cross-references to further information on this website) to conclude the series of Research Updates that has stalled for a while. And to decide whether there is interest in a reviewed publication based on all this work. In the meantime, the 25th anniversary of the foundation of Earthworks (2001 March1) has paased quietly and my 80th birthday approaches. The winding up of my rented office space is foreseen towards the end of the year.