SEAFLOOR SPREADING
and
GLOBAL- or PLATE-TECTONICS

(A) Based on Wegener's "Continental Drift",
..........except for 1960's "Seafloor Spreading - Hess & Dietz.

[B] Important Regions:
.....Mid Ocean Ridges and Rises as Spreading Centers; young, tension
.....Trenches & Mountain Ranges denote Collision ; old, compression
.....Fracture Zones accommodate shear of Plates (Transform Faults)

[C] Name Major Plates: ????
..........Plate Boundaries marked by seismicity and volcanism

[D] Evidence for Global Tectonics' Mobility from geophysics (=indirect) :
..........magnetism, paleomagnetism, seismicity, gravity, heatflow

[E] Some special features: Hot Spots, Terrains, Triple Junctions

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