  The VERCE project has pioneered an e-Infrastructure to support researchers
using established simulation codes on high-performance computers in conjunction
with multiple sources of observational data. This is accessed and organised via
the VERCE science gateway that makes it convenient for seismologists to use
these resources from any location via the Internet. Their data handling is made
flexible and scalable by two Python libraries, ObsPy and dispel4py and by data
services delivered by ORFEUS and EUDAT. Provenance driven tools enable rapid
exploration of results and of the relationships between data, which accelerates
understanding and method improvement. These powerful facilities are integrated
and draw on many other e-Infrastructures. This paper presents the motivation
for building such systems, it reviews how solid-Earth scientists can make
significant research progress using them and explains the architecture and
mechanisms that make their construction and operation achievable. We conclude
with a summary of the achievements to date and identify the crucial steps
needed to extend the capabilities for seismologists, for solid-Earth scientists
and for similar disciplines.
