Long Fingers of Heat Beneath Earth's Surface
Why it Matters: A key mission for the Office of Basic Energy Science is related to new methods and techniques for geosciences imaging from the atomic scale to the kilometer scale. Geophysical imaging methods are needed to measure and monitor subsurface reservoirs for hydrocarbon production or for carbon dioxide storage resulting from large-scale carbon sequestration schemes.
Key Challenges: Development of new approaches for regional and global seismic tomography using high-accuracy numerical schemes that treat wave propagation through complex 3D models of earth structure directly with spectral element methods.
Accomplishments: A new, cutting-edge method for global seismic imaging that would not have been possible without extensive use of NERSC HPC resources has made possible the discovery of a never-before-seen global pattern of seismic shear-wave velocity anomalies in the earth's upper mantle. These features, which are the subject of a paper recently published in Science, shed new light on the dynamic processes at work in the upper mantle, such as those that drive "hotspot" volcanism (e.g. Hawaii).
Investigators: Barbara Romanowicz and Scott French, UC Berkeley