It’s not hard to grasp the basic idea of plate tectonics: There’s a crack in the middle of the ocean floor where magma rises from deep within the planet, forming two seafloor halves that spread apart.
And if we were flat-landers, that would be that. However, the whole thing happens on round and curvy Earth, so plate interactions can get complicated–but also very interesting.
Take the Caribbean plate, for instance–the floor of the Caribbean Sea, south of the Gulf of Mexico, and the land masses around it (including much of Central America).
No one is quite sure how this minor plate formed up through the end of the dinosaur age, but watch how it moves in this elegant, multi-million-year-old dance:
Certainly the Atlantic fits our stereotype of “big crack,” two sides spreading apart for many tens of millions of years in the past (and this likely will continue for far longer into the future than any of us need to consider). But there is a lot more going on in the Caribbean.
And it involves volcanism and earthquakes, both of which are capable of kicking up a tsunami in this part of the world.
The eastern and western ends of the Caribbean plate are currently the most active. In honor of this week’s change in the status of Kick-’em-Jenny volcano near Grenada, let’s start with the eastern side – the Lesser Antilles island arc.
Why are there volcanoes, and accompanying earthquakes, there? The University of the West Indies Seismic Research Centre knows.
Sunday Morning Volcano posts at my other blog on some of these volcanoes include:
That’s only a few of the many Caribbean volcanoes.
Next time we’ll look at volcanoes on the western edge of the Caribbean plate, including one whose eruption may have affected the fate of the Eastern Roman Empire (and certainly affected the nearby Mayan Empire) and another whose Ice-Age eruption may have been big enough to qualify as “super.”
Featured image: Eastern Lesser Antilles (Barbuda to Grenada), Jacques Descloitres, MODIS Rapid Response Team, NASA/GSFC, via Wikimedia.
Allen, R. W.; Berry, C.; Henstock, T. J.; Collier, J. S.; and others. 2018. 30 Years in the Life of an Active Submarine Volcano: A Time‐Lapse Bathymetry Study of the Kick‐‘em‐Jenny Volcano, Lesser Antilles. Geochemistry, Geophysics, Geosystems.
Bachmann, R. 2001. The Caribbean plate and the question of its formation. Institute of Geology, University of Mining and Technology Freiberg Department of Tectonophysics http://www.redciencia.cu/geobiblio/paper/2001_Raik%20Bachmann_THE%20QUESTION%20OF%20ITS%20FORMATION.pdf.
Giunta, G. and Orioli, S. 2011. The Caribbean Plate Evolution: Trying to Resolve a Very Complicated Tectonic Puzzle, New Frontiers in Tectonic Research – General Problems, Sedimentary Basins and Island Arcs, ed, Sharkov, E. InTech, DOI: 10.5772/18723. Available from: https://www.intechopen.com/books/new-frontiers-in-tectonic-research-general-problems-sedimentary-basins-and-island-arcs/the-caribbean-plate-evolution-trying-to-resolve-a-very-complicated-tectonic-puzzle
Macdonald, R.; Hawkesworth, C. J.; and Heath, E. 2000. The Lesser Antilles volcanic chain: a study in arc magmatism. (Abstract only) Earth-Science Reviews. 49(1-4): 1-76.