The Southern California Earthquake Center digital library publishes scientific data generated by seismic wave propagation simulations. The output from a single simulation may be as large as 47 Terabytes of data and 400,000 files. The total size of the digital library is over 130 Terabytes with nearly three million files. We examine how this scale of simulation output can be registered into a digital library built on top of the Storage Resource Broker data grid. We also examine the multiple types of interactive services that have been developed for accessing and displaying the multi-terabyte collection.