Images powerfully shape our thinking about nature.
First-order features like the Cordillera are barely resolved and the characteristic topography within provinces like the Basin and Range and Great Valley are obscured beyond recognition. Yet it is precisely such a fuzzy view of the lithosphere and deeper mantle that we currently bring to the four-dimensional problem of understanding the structure, evolution, and dynamics of the North American continent. Topography of western US at different degrees of resolution. Left, filtered at 500 km, a resolution similar to that of current global tomographic models. As designed, USArray will provide resolution of crustal and upper mantle structure on the order of tens of kilometers.