A version of this animation with labels for the oceans & continents can be viewed at • Ancient Oceans & Continents: Plate Te...
Please cite as:
Scotese, C.R., and Elling, R.P., 2017. Plate Tectonic Evolution during the last 1.5 Billion Years: The Movie. Plate Tectonics at 50, William Smith Meeting, October 35, 2017, The Geological Society, Burlington House, London, p. 1617.
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Plate Tectonic Evolution during the Last 1.5 Billion Years: The Movie
Christopher R. Scotese and Reece Elling
Department of Earth and Planetary Sciences, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208; [email protected]
This computer animation illustrates the plate tectonic development of the continents and ocean basins during the past 1.3 billion years. The GPlates program (https://www.earthbyte.org/gplates20...) was used both to build the plate tectonic model and to produce the animation. The animation shows the evolution of the plates using the continuously closing plate boundary (CCP) technique (Gurnis et al., 2012) that accurately renders the complex, changing topologies along intersecting plate boundaries.
The latitudinal orientation of the continents was derived largely from paleomagnetic data (Van der Voo, 1993; Pisarevsky, 2005; Veikkolainen et al., 2014). Hot spot tracks and seafloor spreading isochrons (Seton et al., 2012; Matthews et al., 2016) were used to constrain the longitudinal positions of the continents back to ~200 million years. Plate tectonic reconstructions older than 200 million years are necessarily more speculative and were derived by combining diverse lines of evidence: the tectonic history of the continents (i.e, the timing of continentcontinent collisions or the ages of rifting), the distribution of paleoclimatic indicators (i.e., bauxites, coals, tillites, and salt deposits; Boucot et al., 2013), and in some cases the biogeographic affinities of fossil faunas and floras (Lees et al., 2002; Cocks and Fortey, 2003; Torsvik and Cocks, 2017).
Though a diverse data set has been used to produce these reconstructions, this data, in itself, was not enough to do the job. So much time has passed, and so little direct evidence of past plate interactions remains, that guidance must also be sought from the “Rules of Plate Tectonics” (Scotese, 2014).
The rules of plate tectonics are largely intuitive. They state that the Earth’s tectonic plates do not move randomly, but rather evolve in a manner that is consistent with the forces that drive them. The principal forces are slab pull, ridge push, and trench rollback. Understanding how these forces work provides important insights into how plate boundaries will evolve through time. Simply said, plates move only if they are pulled back into the mantle by a subducting slab or pushed laterally by a mature midocean ridge system. In this animation, the evolving plate boundaries have been drawn to follow this maxim.
It is also important to note that plate tectonics is a “catastrophic” system. Though “slow and steady” is the general rule, a major plate tectonic reorganization takes place every 50 – 100 million years. These “plate tectonic catastrophes” most often occur when midocean ridges are subducted or when major continents collide. Plate tectonic reorganizations have played an important role in shaping the rock record and providing the evolving context for climate change, the changing distribution of land and sea, and the evolution of distribution of life on Earth.
A preliminary version of the animation can be viewed at: • Plate Tectonic FlipBook by C.R. Scotese .