9730685 Chen Mid-ocean ridges represent the longest plate boundaries on the earth's surface and their persistent volcanism has produced over half of the earth's crust. Understanding mantle upwelling and crustal accretion processes at mid- ocean ridges is important in our understanding how global plate tectonics work to shape the earth's surface. This proposed two-year investigation is designed to construct three-dimensional ridge crustal flow models at a fast spreading mid-ocean ridge. The main goal is to test if the along-axis crustal flow at fast spreading ridges is sufficient to smoothen the gravity, topography, crustal thickness and other observables if mantle upwelling at fast ridges is three-dimensional. This is the key to discriminate between the current two competing hypotheses for the mantle flow and crustal accretion at mid-ocean ridges. This is inexpensive and effective approach toward solving the current dilemma of the production of oceanic crust and its related processes at fast spreading ridges.
