An unprecedented examination of the Earth's deep interior and investigation across a broad range of scales of the structure of the North American continent and the processes that formed it would be among the undertakings of a proposed 10-year Earth Science project called USArray. Now in the planning and development stage, the project would permit a three-dimensional (3-D) systematic investigation of North America, improving the resolution of lithospheric images by an order of magnitude.

For the Earth sciences, the project would be the seismological equivalent of the Hubble space telescope. A number of factors suggest that North America is particularly suited for this project, including the states of current knowledge and technology, the availability of a sophisticated infrastructure, organization in the seismological community scientific economy, and widespread scientific interest.