====== Tectonic subduction ======

Movements of the 'Tectonic Plates' are believed to have formed almost all of the Earth's current-day crust - relying on a process called 'Subduction'.

In that process, the oceanic lithosphere of a tectonic plate collides with the less dense lithosphere of a second plate. Under pressure, the heavier plate slides under the second plate and sinks down into the mantle. See [[https://en.wikipedia.org/wiki/Subduction|Wikipedia]]

But what initiates the process is currently unknown.

One theory is that fluid water lubricates the rock surfaces, creating positive feedback mechanisms which encourage further subduction.

>__The initiation of subduction remains one the unresolved challenges of plate tectonics. __\\ \\ See [[https://www.science.org/doi/10.1126/science.1063891|The Initiation of Subduction: Criticality by Addition of Water?]] //Science// • Vol 294, Issue 5542 • pp. 578-580 (a full copy of which may be found [[http://www.google.com/url?esrc=s&q=&rct=j&sa=U&url=http://rockdef.wustl.edu/seminar/Regenauer-Lieb%2520et%2520al%2520%282001%29.pdf&ved=2ahUKEwim49bAgdD1AhW8QEEAHSb6CXIQFnoECAcQAg&usg=AOvVaw1GabLivz5WpQnPkHDKnTUT|here]] {{:oa_padlock_grn.png?16&nolink|Open Access}})

//Note :// The subject of Plate Tectonics in general is only poorly understood. Not least the question of when it began. The current estimates are at around 3 billion years ago. See [[https://www.nature.com/articles/d41586-024-02602-3|Geology’s biggest mystery]]: //Nature News// Aug. 2024:

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