Upper Crustal Structure of Superfast‐Spread Oceanic Crust Exposed at the Pito Deep Rift: Implications for Seafloor Spreading

A tectonic window into the upper 2,000 m of oceanic crust generated at superfast spreading (∼142 mm/yr) southern East Pacific Rise exposes a continuous layered structure basaltic lavas and sheeted dikes over gabbroic rocks. This relatively simple is in accord with expectations for crustal accretion very fast rate high magma budget where magmatic construction keeps pace plate separation. Detailed observations show that lava flows dip progressively more steeply inward (toward axis they were erupted). Underlying are faulted tectonically rotated to outward. These structures interpreted terms subsidence beneath during allowed unit thicken >400 without creating comparable relief center. Transitional units above below dike complex thickness rock modified by intrusive processes accretion. The shows even approaching end-member seafloor spreading, involves dramatic not obvious from surface geology centers.