Self-replicating subduction zone initiation by polarity reversal

Subduction zone rheology

Rheological flow laws can be obtained from studies using multi-anvil high-pressure systems with synchrotron-based piezometers and strain metrics. The high flux X-ray source provides minute-scale time resolution with accurate measurement of diffraction patterns and direct sample images. Measurements of length changes with an accuracy of one part in 104 are being developed and will provide a new ...

Subduction initiation at relic arcs

Although plate tectonics is well established, how a new subduction zone initiates remains controversial. Based on plate reconstruction and recent ocean drilling within the Izu-Bonin-Mariana, we advance a new geodynamic model of subduction initiation (SI). We argue that the close juxtaposition of the nascent plate boundary with relic oceanic arcs is a key factor localizing initiation of this new...

Subduction initiation: spontaneous and induced

The sinking of lithosphere at subduction zones couples Earth’s exterior with its interior, spawns continental crust and powers a tectonic regime that is unique to our planet. In spite of its importance, it is unclear how subduction is initiated. Two general mechanisms are recognized: induced and spontaneous nucleation of subduction zones. Induced nucleation (INSZ) responds to continuing plate c...

Polarity reversal in hydra by oligomycin.

Intact hydra treated for 24 h with oligomycin gradually lose their head structures and the distal ends form feet. Grafting experiments show that the distal ends of treated animals induce proximal structures.

Initiation of the Andean orogeny by lower mantle subduction