Cascadia subduction zone initiation
The Cascadia subduction zone initiation event formed at around 53–43 Ma likely as an episodic subduction via a trench jump after the large igneous province (LIP) Siletzia accreted.
Subduction is a key geological process where one tectonic plate sinks beneath another into the Earth’s mantle, usually at convergent plate boundaries. It drives mountain building, earthquakes, and volcanic activity, shaping Earth’s surface and its deep interior over Millions of years. Subduction zones recycle oceanic crust, are critically driving plate tectonics, and influence global climate through carbon cycling. Famous observables related to subduction include the Mariana Trench and the Andes Mountains. Dive into observables and models of subduction, the critical process that makes our planet so different from all others we know!
The Cascadia subduction zone initiation event formed at around 53–43 Ma likely as an episodic subduction via a trench jump after the large igneous province (LIP) Siletzia accreted.
The present-day Philippine subduction zone is thought to have started at about 9 Ma via a subduction polarity flip.
The South Sandwich SZI event is estimated to have occurred between 39 and 29 Ma as a new destructive boundary.
The Ryukyu SZI event reinitiated subduction of the Philippine Sea plate below the Eurasian plate through episodic subduction at around 6 Ma.
The Anatolia subduction zone (or ‘Anatolian Neotethys’) started at around 104 Ma as a consequence of fracture zone inversion.
The Oman subduction zone, together with the Anatolian subduction zone, started at around 104 Ma as a consequence of fracture zone inversion.
The New Hebrides-New Britain (NHNB) SZI event evolved into the New Hebrides, San Cristobal, and New Britain trenches by subduction polarity reversal at around 10 Ma.
The Lesser Antilles SZI event that formed the present-day Lesser Antilles subduction zone likely occurred between 59–38 Ma and might be an episodic event.
The onset of the Izu-Bonin-Mariana (IBM) subduction zone likely occurred at around 52 Ma likely along a pre-existing fracture zone after a plate reorganisation.