Spreading ridges, transform faults, strike-slip movement, earthquakes and beachballs

Fig. 1.   Incompatible stress regimes of spreading ridges and transform faults. Directions of principal extensional stress axes compared.  That of the spreading ridges (top left) is sideways (across the ridge) and that for strike-slip movement  on transform faults (small white offsets on the ridges) is diagonal.  ( Blue-grey bands = spreading ridges; black arrows = sense of strike-slip movement according to plate tectonics;  'beachballs':- white quadrant = compression, black quadrant = extension; inset = historical moment tensor solutions for the central mid-Atlantic.)

 
 

Plate tectonics offers no explanation for the discrepancy in the forces stressing the crust during so-called "plate movement".  Extensional stresses related to the spreading ridges are sideways (east-west); extensional stresses related to strike-slip movement on transforms are diagonal (northeast-southwest).  Yet the two supposedly express the same movement, i.e., both are opposite sides of the same temporal coin, both of them consequent on the same stress-system generated by so-called 'convection', or slab-pull.  This is classic plate tectonics -  assuming its conclusion so it can reach its conclusion (junk science), the assumption/  'conclusion' being that the plates are being pulled by descending slabs in subduction zones.

The obvious conclusion is that plate tectonics' interpretation of the relationship between subduction zones, spreading ridges and transform faults is simply wrong.  Transform faults are not strike-slip faults at all, but are, as described here, extensional growth fractures with vertical movement related to the adjustment of the mantle crust to its enlarging substrate.   Any strike-slip adjustment that may occur on them is secondary to their initiation, and related to the outgrowth of the mantle.  And subduction zones are not "subduction" zones, they are zones of overriding.

If tranform faults are the manner in which the ridges are offset and the ocean floors created then there is something wrong if the directions of the stress tensor solutions (the big red arrows) for both are different.  And the reason they are different is that Plate Tectonics does not understand that transform faults are not "strike-slip faults", or a "new set of faults" but are simply the tips of propagating fractures - propagating in the direction of the ridges as they move upwards,  ...hardly faults at all.
 

( More about beachballs - but pure obfuscation about what they mean in terms of the reality of transform faults and mantle dynamics - here.)

Ask a guru, tried and true

 

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