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"There are no good wars, with the following exceptions: the American Revolution, World War II, and the Star Wars Trilogy."
Bart Simpson in "Bart the General" (1990)
Geology played a role in many past conflicts, but can war - even if only a fictional future war - play a role in geological fieldwork?
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The film set of the fictional desert city of Mos Espa, hometown of Anakin Skywalker, was build in 1997 for the movie "Star Wars Episode 1: The Phantom Menace" and then abandoned. Despite being located in the Tunisian desert, it's an easily approachable tourist attraction and therefore well documented by photographs. The dry climate preserves the buildings very well and the only menace for the site comes from the slowly moving barchan dunes - up to 6 meters high windblown accumulations of sand and gypsum grains - so often featured in adventure and science-fiction movies.
The set of Mos Espa, consisting of 20 buildings made of wood and plaster, was build on a flat, clay-rich pan and the city later expanded digitally in size, with dunes only barely visible in the background of some scenes. However the prevailing wind, blowing from east to west, constantly moves the sand grains up the windward slope of the dune, on the steeper downwind slope the sand accumulates - the entire dune is therefore migrating with the wind eastwards, just in the direction of the remains of Mos Espa.
Using the film set as fixed reference point in a quite featureless landscape and comparing a series of satellite images from 2002 to 2009, researchers were able to calculate the migration rate of three larger dunes. With values of 5- 15 meters per year the dunes move on with an average speed, the study notes that the dune located nearest to the film set slowed down over the years, possibly influenced by changes in the wind pattern caused by the encountered artificial obstacles.
However, sooner or later Mos Espa will be buried by the terrestrial dunes. Already today the toe of a smaller dune is touching one of the western buildings and one of the largest observed dunes - large enough to bury the entire site - will move over the film set in estimated 80 years.
Bibliography:
LORENZ, R.D.; GASMI, N.; RADEBAUGH, J.; BARNES, J.W. & ORI, G.G. (2013): Dunes on planet Tatooine: Observation of barchan migration at the Star Wars film set in Tunisia. Geomorphology Vol. 201: 264-271
LORENZ, R.D. & ZIMBELMAN, J.R. (2014): Dune Worlds: How Windblown Sand Shapes Planetary Landscape. Springer Praxis Books - Geophysical Sciences: 308