One descending zone of structural plate pushes beneath another, resulting in the most destructive forces known: earthquake and tsunami. What actions should I take? Where do these risk zones emerge from? Research into geological patterns suggest that subduction may spread like an infection, leaping from one oceanic plate to another—a concept historically challenging to validate.
The findings were “not mere speculation,” stated Joan Duarte, a geologist at the University of Lisbon not involved in the study. “This research grounds its claims in geological evidence.”
Subduction pulls the crust deep into the Earth, complicating the understanding of its origins. New studies provide rare ancient examples indicating possible instances of subduction “infection.” The author highlights evidence of neighboring conflicts leading to the formation of the “Ring of Fire” in East Asia.
Nearly 300 million years ago, what is now China was a cluster of ancient Thetis islands, isolated from the Asian seas. The established subduction zone consumed those oceans, merging land into new continents and forming mountains stretching from Türkiye to China. By around 260 million years ago, subduction appears to have expanded, starting to pull down the adjacent Pacific plate.
“These lethal oceanic activities could have influenced the Pacific plate, initiating its descent beneath the Asian continent,” remarked Mark Allen, a geologist at Durham University in the UK, “I’ve been theorizing about this for some time.”
The critical evidence lies in the “Dupal anomaly,” geochemical markers from the ancient Thetis Sea occurring in the current Indian Ocean. When the authors of the study unexpectedly identified this signature in volcanic rocks from the Western Pacific, they theorized that material from Thetis could migrate eastward between subduction zones. “It’s like discovering fingerprints at a crime scene,” explains Allen.
However, the method of this spreading remains elusive. Researchers postulate that transform faults—the areas where plates slide past each other, similar to the San Andreas fault—might create weaknesses that lead to slight shifts in impact angles or velocities, destabilizing and sinking the dense oceanic crust. Duarte likens the scenario to an underwater sheet of aluminum foil. “The foil stays afloat,” he says.
If the subsidence propagates in this manner, could the Atlantic Ocean be next on the list? The monumental 1755 Lisbon earthquake indicates an early subduction incursion in that area. Duarte proposes that regions of Iberia and the Caribbean could be entering the initial stage of this process. “A new Atlantic ‘Ring of Fire’ might emerge over the next 100 million years.”
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