Louisville Hotspot => Louisville, Marshalls, Ellice ?

[Widdekind]

Do the Louisville seamounts (bottom right) relate to the Marshall - Ellice (Tuvalu) seamounts (center right)? Has the northwest spur of the Australian plate, in obducting some of the Pacific plate, obducted dozens of seamounts which originally spanned the gap between the Louisville & Marshall - Ellice (Tuvalu) igneous provinces ?? Visually, the Louisville seamounts run in a straight line towards the Ellice (Tuvalu) islands, intercepted only by the "corner" of the Australian plate. If so, then the linear length, of the northwest-trending section, of the "Louisville - Ellice (Tuvalu) - Marshall" seamount chain, represents the original length, of the Emperor island chain, much of which has by now sub-ducted, under Siberia. The "Hawaii - Emperor", "Louisville - Ellice (Tuvalu) - Marshall", and "Tuamoto - Line islands" chains all represent Hot Spots, "stitching" through the moving Pacific plate, over the past ~125 Myr (inferring an association with the emplacement, of the massive Ontong-Java oceanic flood basalt Large-Igneous-Province, at that time):

 

 

Edited September 28, 2012 by Widdekind

[Widdekind]

Perhaps the Hot-Spot seamount chains in the south Pacific were emplaced, at ancient spreading ridges, as part of the undersea volcanism associated with spreading ridges. I.e. the southern Pacific seamounts represent sites of particularly vigorous, but otherwise normal, spreading ridge activity. If so, then the eroded appearance, of those seamount chains (Magellan - Tuamotu, Line - Austral), as compared to the Hawaii - Emperor chain, is attributable to older age, increased erosion, and increased seafloor sedimentation which has "silted all the way up the slopes" of some seamounts, so that only their top-most tips still protrude through the accumulated "marine snow", a little like mountaintops protruding above glaciers? If the Magellans & Mid-Pacific seamounts were emplaced 170 Mya, when the Pacific basin began forming; then they are twice the age of the oldest Emperor seamounts.