Aleutians are extension of Emperor-Hawaii chain?

[Widdekind]

Before 43 Mya, the Pacific oceanic plate was traveling northwards. Then, in a sudden shift, it began migrating northwestwards. This "jarring change in course" created a 'kink' in the Hawaii-Emperor volcanic island chain, erupted by the Hawaii Hot-Spot. Thus, before 43 Mya, only the Emperor islands existed; and, they 'trailed away', from the Hawaii Hot-Spot, in a northerly direction, at least as far as the Meiji sea-mount. And so, if, before 43 Mya, the Emperor islands extended even farther northwards, then the westerly motion, of the Pacific Plate, since that time, could have 'scraped off' those northern-most sea-mounts, onto the coast of Alaska, creating the Aleutian island chain. If so, then the Aleutian islands are 'accreted' Emperor islands:

 

Note, that the 3000 km of Emperor islands were erupted over ~40 Myr. Thus, an inferred additional +2000 km of more northerly islands (see figure) suggests +30 Myr, indicating that the Hawaii Hot-Spot has been erupting for at least ~110 Myr.

Edited May 31, 2011 by Widdekind

[Widdekind]

Juan de Fuca & Cocos oceanic plates are fragments of Eocene oceanic 'Farallon' plate 43 Mya, whose collision with California coast caused sudden shift, in Pacific plate motion

 

Currently, California overlies the ancient, Eocene, 'de Fuca-Cocos / Pacific' plates Mid-Ocean Ridge (MOR). California obducted that MOR probably about 5 Mya, based upon plate speeds, and distances obducted; and, is closely associated with an 11 degree northwards back-shift, in the direction of Pacific plate propagation, 3.5 Mya, evidently as the California coast, having crested the MOR, began moving 'back down the back-slope' of the same.

 

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Wikipedia

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Oceanic Crust is 'laterally loaded' with considerable compression forces, periodically causing long, linear 'shear faults', that apparently cut across the crustal plate

 

Crustal plate collisions can subject the participating plates to differential forces. For example, when California continental crust contacted the Farallon oceanic plate, c.45 Mya, it acted like the 'bow of an ice-breaker'. A long, linear 'shear fault' apparently propagated horizontally, cutting across the oceanic crustal plate, crossing the MOR, and penetrating into, and cutting across, the Pacific plate, too. 40 Myr later, the 'tip' of Baha California apparently provoked a subsequent similar faulting. The appearance of these 'shear faults' may relate to dramatic changes in 'lateral loadings', leading to a 'stair-step' discontinuous MOR, when the 'pushing plate' impacts with jutting 'bow-of-ice-breaker' headlands, or 'catching cavity' bays. Such suggests, that ocean floors are subjected to sizable 'squeezing' strains, in addition to vertical pressure gradients.

 

Edited May 31, 2011 by Widdekind