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This is a time lapse movie of Canary Springs at Mammoth, over a period of about 18 months. As you watch the landscape develop, observe the tree in the center of the image being engulfed by the growing travertine, and the way in which the larger ponds grow by "eating" the smaller ponds These characteristic dynamics were predicted by the theoretical models developed by us, and simulated below. Download movies ...

Credits: Brian Suderman (Photography).

Computer simulation of the growth of travertine terraces, using a cell dynamical system technique. An initially sloped surface with small random perturbations develops instabilities that grow into ponds and terraces away from the vent. In this simulation, tracer dye has been injected into the water to visualise the flow path.
Our computer simulations are capable of following the spatial and temporal development of environmental variables, including temperature, microbe concentration, chemical composition. In this simulation, the temperature field was visualized and colored according to the pigmentation of the microbes that can live at each temperature.
The modelling technique used in our simulations is not a traditional numerical method. Instead we use a discrete space-time formulation that is computationally efficient, and capable of resolving on a desktop computer the level of detail usually associated with supercomputer simulations. Our work shows that the results we obtain in this way are equivalent to those that would be obtained by standard approaches. Download movies ...
Fly-by tour of a simulated terrace system. Note the large pond system near the vent, the deployment of roughly semi-circular ponds near the vent, and the eventual characteristic terrace morphology further downstream. These morphological changes are generically seen in our field observations, and result from an interplay between landscape geometry and fluid dynamics.
Under conditions of slow flow rate and a nearly horizontal baseline surface, the travertine grows into circularly symmetric dome shapes, as shown in this movie, and in our field observations presented on the following page. These domes are simple enough that we can understand them mathematically as well as computationally, allowing us to compare our different modeling approaches.
Next page:
A detailed look at travertine domes

Credits. The computer simulations on this page were generated by John Veysey and Nigel Goldenfeld, and rendered with assistance from Nicholas Guttenberg. We gratefully acknowledge the assistance of the National Park Service at Yellowstone National Park during this project.

A technical report about our work is available online.

Based on research supported by the National Science Foundation Biocomplexity in the Environment Program, through grant number NSF-EAR-02-21743.  (c) 2006.  Nigel Goldenfeld, Pak Yuen Chan, Nicholas Guttenberg and John Veysey.  All rights reserved. 

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